駒場学部講義2015 総合情報学特論III 「意識の神経科学:「気づき」と「サリエンシー」を手がかりに」Masatoshi Yoshida
1. The document summarizes a lecture about the neural basis of consciousness, focusing on awareness, attention, and the study of blindsight.
2. It discusses evidence that the dorsal visual pathway is involved in vision for action while the ventral pathway is involved in vision for perception.
3. In blindsight, there is a "feeling of something happening" in the blind field that can be explained by saliency computation and sensorimotor contingencies rather than conscious visual experience.
This document summarizes a lecture on attention and motor control. It discusses different types of attention like selective and sustained attention. It examines how attention and eye movements are controlled by brain regions like the frontal eye field and superior colliculus. The lecture also explores the dorsal and ventral attention networks in the brain and how the saliency model can be used to predict eye gaze and has clinical applications for disorders like ADHD, autism and schizophrenia.
1. Blindsight refers to the phenomenon where patients with damage to visual cortex demonstrate visually guided behaviors despite reporting no visual experience or perception. This suggests the existence of two visual systems - a cortical system for visual perception and a subcortical system for visual processing without awareness.
2. Evidence from studies in monkeys, rodents, and frogs support the two visual systems hypothesis, finding that lesions to visual cortex impair perception but not all visually guided behaviors, which can still be mediated by the subcortical system.
3. In humans, the dorsal visual pathway is thought to underlie blindsight by allowing visual information processing without awareness, while the ventral pathway is necessary for conscious visual experience. However, the specific
This document summarizes two lectures about consciousness and neuroscience:
1) It discusses theories of consciousness such as qualia and awareness, and the distinction between the dorsal and ventral visual pathways and their roles in vision for action vs perception. It also covers blindsight and the idea that a "feeling of something" without qualia may arise from saliency computation.
2) It discusses using bistable percepts like binocular rivalry to study neural correlates of awareness. It introduces the ideas of neurophenomenology and heterophenomenology to study first-person experience through intersubjective methods. It provides an example of neurophenomenology applied to the aura experience before epileptic seizures.
Week 4 the neural basis of consciousness introduction to the visual systemNao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) What are behavioral and neural signatures of nonconscious processing?
2) Can blindsight-like behavior induced in monkeys? What are the evidence?
3) How can we discriminate nonconscious from conscious behaviors using a concept of metacognition?
4) What is the structure of eye and how does it shape our conscious vision?
Week 2 neural basis of consciousness: introduction to the research methods ts...Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) How can we characterize our phenomenology
- Introduction to psychophysical methods
2) How can we measure neural activity in the brain?
- What is the source of the neural activity?
Growing evidence for separate neural mechanisms for attention and consciousne...Nao (Naotsugu) Tsuchiya
1) The document discusses recent evidence that attention and consciousness are dissociable and may have separate neural mechanisms. Studies using dual-task paradigms have shown consciousness can occur without attention.
2) Steady state visual evoked potentials (SSVEPs) have been used to track attention and consciousness during binocular rivalry. However, SSVEPs track attention but not necessarily consciousness.
3) Going forward, researchers aim to characterize the structures of qualia and brain information to better understand the relationship between consciousness and neural activity, with attention seen as a way to perturb these structures.
駒場学部講義2015 総合情報学特論III 「意識の神経科学:「気づき」と「サリエンシー」を手がかりに」Masatoshi Yoshida
1. The document summarizes a lecture about the neural basis of consciousness, focusing on awareness, attention, and the study of blindsight.
2. It discusses evidence that the dorsal visual pathway is involved in vision for action while the ventral pathway is involved in vision for perception.
3. In blindsight, there is a "feeling of something happening" in the blind field that can be explained by saliency computation and sensorimotor contingencies rather than conscious visual experience.
This document summarizes a lecture on attention and motor control. It discusses different types of attention like selective and sustained attention. It examines how attention and eye movements are controlled by brain regions like the frontal eye field and superior colliculus. The lecture also explores the dorsal and ventral attention networks in the brain and how the saliency model can be used to predict eye gaze and has clinical applications for disorders like ADHD, autism and schizophrenia.
1. Blindsight refers to the phenomenon where patients with damage to visual cortex demonstrate visually guided behaviors despite reporting no visual experience or perception. This suggests the existence of two visual systems - a cortical system for visual perception and a subcortical system for visual processing without awareness.
2. Evidence from studies in monkeys, rodents, and frogs support the two visual systems hypothesis, finding that lesions to visual cortex impair perception but not all visually guided behaviors, which can still be mediated by the subcortical system.
3. In humans, the dorsal visual pathway is thought to underlie blindsight by allowing visual information processing without awareness, while the ventral pathway is necessary for conscious visual experience. However, the specific
This document summarizes two lectures about consciousness and neuroscience:
1) It discusses theories of consciousness such as qualia and awareness, and the distinction between the dorsal and ventral visual pathways and their roles in vision for action vs perception. It also covers blindsight and the idea that a "feeling of something" without qualia may arise from saliency computation.
2) It discusses using bistable percepts like binocular rivalry to study neural correlates of awareness. It introduces the ideas of neurophenomenology and heterophenomenology to study first-person experience through intersubjective methods. It provides an example of neurophenomenology applied to the aura experience before epileptic seizures.
Week 4 the neural basis of consciousness introduction to the visual systemNao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) What are behavioral and neural signatures of nonconscious processing?
2) Can blindsight-like behavior induced in monkeys? What are the evidence?
3) How can we discriminate nonconscious from conscious behaviors using a concept of metacognition?
4) What is the structure of eye and how does it shape our conscious vision?
Week 2 neural basis of consciousness: introduction to the research methods ts...Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) How can we characterize our phenomenology
- Introduction to psychophysical methods
2) How can we measure neural activity in the brain?
- What is the source of the neural activity?
Growing evidence for separate neural mechanisms for attention and consciousne...Nao (Naotsugu) Tsuchiya
1) The document discusses recent evidence that attention and consciousness are dissociable and may have separate neural mechanisms. Studies using dual-task paradigms have shown consciousness can occur without attention.
2) Steady state visual evoked potentials (SSVEPs) have been used to track attention and consciousness during binocular rivalry. However, SSVEPs track attention but not necessarily consciousness.
3) Going forward, researchers aim to characterize the structures of qualia and brain information to better understand the relationship between consciousness and neural activity, with attention seen as a way to perturb these structures.
This document provides an overview of the learning objectives and topics to be covered in Week 1 of a course on the neural basis of consciousness. The key questions to be answered are: a) Why are we interested in consciousness? b) What do we mean by consciousness? c) How can we study consciousness? d) What are the challenges of understanding consciousness in animals, plants and robots? The document discusses phenomenology, experimental approaches, theories of consciousness and challenges in the field. It also provides an introduction to relevant neuroanatomy and encourages students to learn basic terminology to prepare for future assessments.
Week 8 : The neural basis of consciousness : consciousness vs. attention Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) How can we define “attention”?
2) What are the paradigms to manipulate attention?
3) What are the neuronal mechanisms of attention?
4) How can we explain the relationship between attention and consciousness?
Week 3 the neural basis of consciousness overview of important clinical cas...Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) Why are the studies of brain lesioned patients important?
2) What are reported phenomenology by patients?
3) How can we assess / validate their phenomenology?
- Behavioral & Neuronal studies of patients
Week 9 the neural basis of consciousness : dissociation of consciousness &...Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) What are the logic and evidence of experiments which demonstrate dissociation between attention and consciousness?
2) How do they manipulate & assess consciousness?
3) How do they manipulate & assess attention?
Magic is an ancient performance art that has been used by magicians to experimentally determine how to best manipulate human attention and perception. Through informal experimentation, magicians have developed techniques to divert attention or exploit weaknesses in human vision and awareness. Their intuitive understanding of behavior and perception in some cases exceeds that of neuroscientists. The document argues that studying magic techniques could provide insights for neuroscientists into the neural bases of attention, awareness, and perception. It presents several examples of visual illusions commonly used in magic tricks and their underlying neural mechanisms, such as the spoon bending illusion and the persistence of vision illusion, arguing they could be applied to study consciousness.
Week 11 neural basis of consciousness : consciousness and integration (1)Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) How can we compute integrated information?
2) How we can estimate the proposed boundary of consciousness?
3) What are the reported phenomenology / behaviors of split brain patients?
4) How does IIT explain various known facts about consciousness, such as split brain patients?
This document outlines a course on the cognitive and neural basis of numerical abilities. The course will cover topics such as the perception and representation of numerical quantity in the brain, number neurons in humans and other animals, and the cerebral circuits underlying simple arithmetic. It will also discuss cultural variability and universal mechanisms in numerical cognition, as well as how numbers relate to other domains like language and space. Each class will include more detailed discussion of relevant studies using methods like fMRI, EEG, and behavioral experiments.
This document provides an overview of key concepts in sensation and perception. It begins by defining sensation as the process by which sensory receptors receive stimulation from the environment and transmit that information to the brain. Perception is defined as the process of selecting, organizing, and interpreting sensory information to recognize meaningful objects and events. The document then discusses several principles of perception, including that perception is an active constructive process, not a passive recording of external stimuli. It presents examples of perceptual illusions and organization to illustrate this. Subsequent sections discuss theories of perception, the distinction between active and passive touch, and Gibson's theory of affordances. The document emphasizes that perception involves an engagement with the world through action and exploration, not just internal representations in the
Chapter 6: Perception
Selective Attention
At any moment we are conscious of a very limited amount of all that we are capable of experiencing. One example of this selective attention is the cocktail party effect—attending to only one voice among many. Another example is inattentional blindness, which refers to our blocking of a brief visual interruption when focusing on other sights.
Perceptual Illusions
Visual and auditory illusions were fascinating scientists even as psychology emerged. Explaining illusions required an understanding of how we transform sensations into meaningful perceptions, so the study of perception became one of psychology’s first concerns. Conflict between visual and other sensory information is usually resolved with the mind’s accepting the visual data, a tendency known as visual capture.
Perceptual Organization
From a top-down perspective, we see how we transform sensory information into meaningful perceptions when we are aided by knowledge and expectations.
The early Gestalt psychologists were impressed with the seemingly innate way we organize fragmentary sensory data into whole perceptions. Our minds structure the information that comes to us in several demonstrable ways:
Form Perception
To recognize an object, we must first perceive it (see it as a figure) as distinct from its surroundings (the ground). We must also organize the figure into a meaningful form. Several Gestalt principles—proximity, similarity, continuity, connectedness, and closure—describe this process.
Depth Perception
Research on the visual cliff revealed that many species perceive the world in three dimensions at, or very soon after, birth. We transform two-dimensional retinal images into three-dimensional perceptions by using binocular cues, such as retinal disparity, and monocular cues, such as the relative sizes of objects.
Motion Perception
Our brain computes motion as objects move across or toward the retina. Large objects appear to move more slowly than smaller objects. A quick succession of images, as in a motion picture or on a lighted sign, can also create an illusion of movement.
Perceptual Constancy
Having perceived an object as a coherent figure and having located it in space, how then do we recognize it—despite the varying images that it may cast on our retinas? Size, shape, and lightness constancies describe how objects appear to have unchanging characteristics regardless of their distance, shape, or motion. These constancies explain several of the well-known visual illusions. For example, familiarity with the size-distance relationships in a carpentered world of rectangular shapes makes people more susceptible to the Müller-Lyer illusion.
Perceptual Interpretation
The most direct tests of the nature-nurture issue come from experiments that modify human perceptions.
Sensory Deprivation and Restored Vision
For many species, infancy is a critical period during which experience must activate the brain’s innate visual mechanisms. If cataract removal restores eyesight to adults who were blind from birth, they remain unable to perceive the world normally. Generally, they can distinguish figure from ground and can perceive colors, but they are unable to recognize shapes and forms. In controlled experiments, animals have been reared with severely restricted visual input. When their visual exposure is returned to normal, they, too, suffer enduring visual handicaps.
Perceptual Adaptation
Human vision is remarkably adaptable. Given glasses that shift the world slightly to the left or right, or even turn it upside down, people manage to adapt their movements and, with practice, to move about with ease.
Perceptual Set
Clear evidence that perception is influenced by our experience—our learned assumptions and beliefs—as well as by sensory input comes from the many demonstrations of perceptual set and context effects. The schemas we have learned help us to interpret otherwise ambiguous stimu
The document discusses Streff Syndrome, a visual disorder caused by stress. It begins by explaining how vision works through the visual pathway in the brain. Streff Syndrome occurs when there is a breakdown between visual motor function and sensory function due to stress. It usually affects children and causes reduced vision in both eyes. Treatment includes low prescription eyewear to reduce visual stress and allow the visual system to recover normally within 6 weeks, as well as vision therapy and reducing stressors.
This document discusses the distribution of cognition across individuals, tools, language, and methodology (H-LAM/T systems). It suggests that improving individual effectiveness in society should be approached as a system engineering problem by studying the interacting whole using a synthesis-oriented approach. The document also discusses using control theory and information theory to explain cognitive and social phenomena (cybernetics). Finally, it discusses using paired analytics sessions with a visual analyst and domain expert to collaborate on analytic tasks and influence design decisions in aviation safety.
The document discusses challenges with the traditional view of psychological architecture for behavior, which depicts perception, cognition, and action as distinct sequential processes. It notes that this view was designed to explain human problem-solving and assumes a disembodied mind. The document questions where the "central executive" of cognition is located in the brain, as neural correlates of decision-making are found in many regions. It suggests this traditional view may not adequately explain neural data and that brains could be considered control systems rather than strictly input/output devices.
Fundamentals of visual communication unit iiiRangarajanN6
Visual perception involves the five senses of sight, touch, smell, taste, and sound, as well as proprioception. It is the process by which we detect stimuli in the environment and take actions based on that information. Perception includes both bottom-up processing, where perception begins with sensory stimuli, and top-down processing, where contextual information aids perception. Optical illusions demonstrate how perception does not always match physical reality due to cognitive influences on what we see. Gestalt principles of perception, such as similarity, continuity, and closure, describe how we tend to group visual elements.
This document summarizes recent research on human visual perception and its relevance to visualization and computer graphics. It discusses how:
1) The human visual system can rapidly categorize images into regions and properties based on simple parallel computations, before focused attention (called preattentive processing).
2) Five theories of preattentive processing are described, focusing on a limited set of basic visual features (color, size, orientation etc.) that can be detected very quickly.
3) Later research showed that attention still influences early vision, and what we see depends on where attention is focused and what is already in our visual memory.
Visual perception involves integrating visual information from the retina and turning it into cognitive concepts that can be used for decision making. It occurs through a pathway from the retina to the lateral geniculate nucleus to the primary visual cortex and then splits into the dorsal and ventral streams. Disorders can impact this process and cause difficulties with visual attention, scanning, memory and recognition that can be assessed through tests of visual fields, acuity, and visual perceptual skills. Occupational therapy focuses on understanding how visual impairments limit activities and developing interventions to address specific deficits.
1) The document discusses using implicit tests to measure consumer perceptions beyond what they explicitly say. It explains how implicit tests can reveal unconsciously associated values with brands or products.
2) A case study is described where a brand wants to develop new packaging that conveys key values. Implicit association tests were used along with explicit questioning to evaluate how well 5 prototype packs conveyed the brand's values.
3) The results showed the top performing prototype packs increased positive purchase intent compared to the current packaging, though the current pack still had the highest intent. Implicit tests provided insights beyond what consumers explicitly reported.
Victorvan Rij Sesti weaksignals Cognitive Enhancement2010Victor Van Rij
The document discusses cognitive enhancement and identifies weak signals related to its development. It covers:
1) Past and potential future pathways of cognitive enhancement, including social/educational and biological methods.
2) Hopes for enhancement like preventing impairment, and fears around risks to humanity.
3) A search identifying 40 weak signals, mostly in biology and tools, with few on social/psychological impacts.
4) Key emerging issues relate to neuroimaging, implants, drugs and genetics raising concerns around ethics, equality and eugenics.
5) Further analysis is needed on costs/benefits of different enhancement methods and priorities between performance vs. development. weak signals were somewhat limited in identifying societal and economic impacts.
Between cognition and feelings during art therapy interventions סופיRuth Harpaz
The document discusses art therapy and how it uses creative processes to improve physical, mental, and emotional well-being. It explores how art therapy is a cognitive and emotional diagnostic and treatment process that allows unconscious thoughts and feelings to be non-verbally expressed. The summary explores how recent research has examined information processing in the brain during art therapy and the interactions between cognitive and emotional processing.
How the brain works and does not work - Erin Legion Hall - March 8 2012jdspafford
1. The brain is a complex organ that is highly sensitive to injury.
2. It integrates sensory information from different modalities and interprets this information to create our perception of reality.
3. The brain is divided between the left and right hemispheres which have specialized but interconnected functions important for tasks, context, and perspective.
4. A critical feature of the human brain that enabled culture is mirror neurons, which allow for imitation, empathy, language, and motor planning.
Here are 3 more possible assessment actions:
9. Instruct the patient to copy a simple shape like a circle or square to assess visual-spatial skills.
10. Present the patient with a daily schedule and ask them to point to or indicate what activity comes next to check sequencing ability.
Week 5 neural basis of consciousness eyes, early visual system and conscious...Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) What is our peripheral experience?
- A closer look with color, motion, and metacognition
2) What neural mechanisms underlie the transmission of visual input from the eyes to the brain?
3) What is a receptive field of a neuron?
4) What are the key properties of V1 (the primary visual cortex)?
5) What are the implications of the properties of V1 for conscious phenomenology?
6) What are the visual pathways from the eyes to the brain, and its implication for blindsight?
The document discusses phi phenomena, which are optical illusions of motion perceived when viewing static images in rapid succession. It describes several types of illusions, including phi, motion pictures, and stroboscopic motion. Theories about how phi phenomena work include inference theory, which suggests the brain infers motion from sensory inputs based on past experience, and brain field theory, which proposes tensions in the brain motivate perceptions of whole objects and events. Phi phenomena led to significant research in visual perception and the founding of Gestalt psychology.
This document provides an overview of the learning objectives and topics to be covered in Week 1 of a course on the neural basis of consciousness. The key questions to be answered are: a) Why are we interested in consciousness? b) What do we mean by consciousness? c) How can we study consciousness? d) What are the challenges of understanding consciousness in animals, plants and robots? The document discusses phenomenology, experimental approaches, theories of consciousness and challenges in the field. It also provides an introduction to relevant neuroanatomy and encourages students to learn basic terminology to prepare for future assessments.
Week 8 : The neural basis of consciousness : consciousness vs. attention Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) How can we define “attention”?
2) What are the paradigms to manipulate attention?
3) What are the neuronal mechanisms of attention?
4) How can we explain the relationship between attention and consciousness?
Week 3 the neural basis of consciousness overview of important clinical cas...Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) Why are the studies of brain lesioned patients important?
2) What are reported phenomenology by patients?
3) How can we assess / validate their phenomenology?
- Behavioral & Neuronal studies of patients
Week 9 the neural basis of consciousness : dissociation of consciousness &...Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) What are the logic and evidence of experiments which demonstrate dissociation between attention and consciousness?
2) How do they manipulate & assess consciousness?
3) How do they manipulate & assess attention?
Magic is an ancient performance art that has been used by magicians to experimentally determine how to best manipulate human attention and perception. Through informal experimentation, magicians have developed techniques to divert attention or exploit weaknesses in human vision and awareness. Their intuitive understanding of behavior and perception in some cases exceeds that of neuroscientists. The document argues that studying magic techniques could provide insights for neuroscientists into the neural bases of attention, awareness, and perception. It presents several examples of visual illusions commonly used in magic tricks and their underlying neural mechanisms, such as the spoon bending illusion and the persistence of vision illusion, arguing they could be applied to study consciousness.
Week 11 neural basis of consciousness : consciousness and integration (1)Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) How can we compute integrated information?
2) How we can estimate the proposed boundary of consciousness?
3) What are the reported phenomenology / behaviors of split brain patients?
4) How does IIT explain various known facts about consciousness, such as split brain patients?
This document outlines a course on the cognitive and neural basis of numerical abilities. The course will cover topics such as the perception and representation of numerical quantity in the brain, number neurons in humans and other animals, and the cerebral circuits underlying simple arithmetic. It will also discuss cultural variability and universal mechanisms in numerical cognition, as well as how numbers relate to other domains like language and space. Each class will include more detailed discussion of relevant studies using methods like fMRI, EEG, and behavioral experiments.
This document provides an overview of key concepts in sensation and perception. It begins by defining sensation as the process by which sensory receptors receive stimulation from the environment and transmit that information to the brain. Perception is defined as the process of selecting, organizing, and interpreting sensory information to recognize meaningful objects and events. The document then discusses several principles of perception, including that perception is an active constructive process, not a passive recording of external stimuli. It presents examples of perceptual illusions and organization to illustrate this. Subsequent sections discuss theories of perception, the distinction between active and passive touch, and Gibson's theory of affordances. The document emphasizes that perception involves an engagement with the world through action and exploration, not just internal representations in the
Chapter 6: Perception
Selective Attention
At any moment we are conscious of a very limited amount of all that we are capable of experiencing. One example of this selective attention is the cocktail party effect—attending to only one voice among many. Another example is inattentional blindness, which refers to our blocking of a brief visual interruption when focusing on other sights.
Perceptual Illusions
Visual and auditory illusions were fascinating scientists even as psychology emerged. Explaining illusions required an understanding of how we transform sensations into meaningful perceptions, so the study of perception became one of psychology’s first concerns. Conflict between visual and other sensory information is usually resolved with the mind’s accepting the visual data, a tendency known as visual capture.
Perceptual Organization
From a top-down perspective, we see how we transform sensory information into meaningful perceptions when we are aided by knowledge and expectations.
The early Gestalt psychologists were impressed with the seemingly innate way we organize fragmentary sensory data into whole perceptions. Our minds structure the information that comes to us in several demonstrable ways:
Form Perception
To recognize an object, we must first perceive it (see it as a figure) as distinct from its surroundings (the ground). We must also organize the figure into a meaningful form. Several Gestalt principles—proximity, similarity, continuity, connectedness, and closure—describe this process.
Depth Perception
Research on the visual cliff revealed that many species perceive the world in three dimensions at, or very soon after, birth. We transform two-dimensional retinal images into three-dimensional perceptions by using binocular cues, such as retinal disparity, and monocular cues, such as the relative sizes of objects.
Motion Perception
Our brain computes motion as objects move across or toward the retina. Large objects appear to move more slowly than smaller objects. A quick succession of images, as in a motion picture or on a lighted sign, can also create an illusion of movement.
Perceptual Constancy
Having perceived an object as a coherent figure and having located it in space, how then do we recognize it—despite the varying images that it may cast on our retinas? Size, shape, and lightness constancies describe how objects appear to have unchanging characteristics regardless of their distance, shape, or motion. These constancies explain several of the well-known visual illusions. For example, familiarity with the size-distance relationships in a carpentered world of rectangular shapes makes people more susceptible to the Müller-Lyer illusion.
Perceptual Interpretation
The most direct tests of the nature-nurture issue come from experiments that modify human perceptions.
Sensory Deprivation and Restored Vision
For many species, infancy is a critical period during which experience must activate the brain’s innate visual mechanisms. If cataract removal restores eyesight to adults who were blind from birth, they remain unable to perceive the world normally. Generally, they can distinguish figure from ground and can perceive colors, but they are unable to recognize shapes and forms. In controlled experiments, animals have been reared with severely restricted visual input. When their visual exposure is returned to normal, they, too, suffer enduring visual handicaps.
Perceptual Adaptation
Human vision is remarkably adaptable. Given glasses that shift the world slightly to the left or right, or even turn it upside down, people manage to adapt their movements and, with practice, to move about with ease.
Perceptual Set
Clear evidence that perception is influenced by our experience—our learned assumptions and beliefs—as well as by sensory input comes from the many demonstrations of perceptual set and context effects. The schemas we have learned help us to interpret otherwise ambiguous stimu
The document discusses Streff Syndrome, a visual disorder caused by stress. It begins by explaining how vision works through the visual pathway in the brain. Streff Syndrome occurs when there is a breakdown between visual motor function and sensory function due to stress. It usually affects children and causes reduced vision in both eyes. Treatment includes low prescription eyewear to reduce visual stress and allow the visual system to recover normally within 6 weeks, as well as vision therapy and reducing stressors.
This document discusses the distribution of cognition across individuals, tools, language, and methodology (H-LAM/T systems). It suggests that improving individual effectiveness in society should be approached as a system engineering problem by studying the interacting whole using a synthesis-oriented approach. The document also discusses using control theory and information theory to explain cognitive and social phenomena (cybernetics). Finally, it discusses using paired analytics sessions with a visual analyst and domain expert to collaborate on analytic tasks and influence design decisions in aviation safety.
The document discusses challenges with the traditional view of psychological architecture for behavior, which depicts perception, cognition, and action as distinct sequential processes. It notes that this view was designed to explain human problem-solving and assumes a disembodied mind. The document questions where the "central executive" of cognition is located in the brain, as neural correlates of decision-making are found in many regions. It suggests this traditional view may not adequately explain neural data and that brains could be considered control systems rather than strictly input/output devices.
Fundamentals of visual communication unit iiiRangarajanN6
Visual perception involves the five senses of sight, touch, smell, taste, and sound, as well as proprioception. It is the process by which we detect stimuli in the environment and take actions based on that information. Perception includes both bottom-up processing, where perception begins with sensory stimuli, and top-down processing, where contextual information aids perception. Optical illusions demonstrate how perception does not always match physical reality due to cognitive influences on what we see. Gestalt principles of perception, such as similarity, continuity, and closure, describe how we tend to group visual elements.
This document summarizes recent research on human visual perception and its relevance to visualization and computer graphics. It discusses how:
1) The human visual system can rapidly categorize images into regions and properties based on simple parallel computations, before focused attention (called preattentive processing).
2) Five theories of preattentive processing are described, focusing on a limited set of basic visual features (color, size, orientation etc.) that can be detected very quickly.
3) Later research showed that attention still influences early vision, and what we see depends on where attention is focused and what is already in our visual memory.
Visual perception involves integrating visual information from the retina and turning it into cognitive concepts that can be used for decision making. It occurs through a pathway from the retina to the lateral geniculate nucleus to the primary visual cortex and then splits into the dorsal and ventral streams. Disorders can impact this process and cause difficulties with visual attention, scanning, memory and recognition that can be assessed through tests of visual fields, acuity, and visual perceptual skills. Occupational therapy focuses on understanding how visual impairments limit activities and developing interventions to address specific deficits.
1) The document discusses using implicit tests to measure consumer perceptions beyond what they explicitly say. It explains how implicit tests can reveal unconsciously associated values with brands or products.
2) A case study is described where a brand wants to develop new packaging that conveys key values. Implicit association tests were used along with explicit questioning to evaluate how well 5 prototype packs conveyed the brand's values.
3) The results showed the top performing prototype packs increased positive purchase intent compared to the current packaging, though the current pack still had the highest intent. Implicit tests provided insights beyond what consumers explicitly reported.
Victorvan Rij Sesti weaksignals Cognitive Enhancement2010Victor Van Rij
The document discusses cognitive enhancement and identifies weak signals related to its development. It covers:
1) Past and potential future pathways of cognitive enhancement, including social/educational and biological methods.
2) Hopes for enhancement like preventing impairment, and fears around risks to humanity.
3) A search identifying 40 weak signals, mostly in biology and tools, with few on social/psychological impacts.
4) Key emerging issues relate to neuroimaging, implants, drugs and genetics raising concerns around ethics, equality and eugenics.
5) Further analysis is needed on costs/benefits of different enhancement methods and priorities between performance vs. development. weak signals were somewhat limited in identifying societal and economic impacts.
Between cognition and feelings during art therapy interventions סופיRuth Harpaz
The document discusses art therapy and how it uses creative processes to improve physical, mental, and emotional well-being. It explores how art therapy is a cognitive and emotional diagnostic and treatment process that allows unconscious thoughts and feelings to be non-verbally expressed. The summary explores how recent research has examined information processing in the brain during art therapy and the interactions between cognitive and emotional processing.
How the brain works and does not work - Erin Legion Hall - March 8 2012jdspafford
1. The brain is a complex organ that is highly sensitive to injury.
2. It integrates sensory information from different modalities and interprets this information to create our perception of reality.
3. The brain is divided between the left and right hemispheres which have specialized but interconnected functions important for tasks, context, and perspective.
4. A critical feature of the human brain that enabled culture is mirror neurons, which allow for imitation, empathy, language, and motor planning.
Here are 3 more possible assessment actions:
9. Instruct the patient to copy a simple shape like a circle or square to assess visual-spatial skills.
10. Present the patient with a daily schedule and ask them to point to or indicate what activity comes next to check sequencing ability.
Week 5 neural basis of consciousness eyes, early visual system and conscious...Nao (Naotsugu) Tsuchiya
12-week lecture series on "the neural basis of consciousness" by Prof Nao Tsuchiya.
Given to 3rd year undergraduate level. No prerequisites.
Contents:
1) What is our peripheral experience?
- A closer look with color, motion, and metacognition
2) What neural mechanisms underlie the transmission of visual input from the eyes to the brain?
3) What is a receptive field of a neuron?
4) What are the key properties of V1 (the primary visual cortex)?
5) What are the implications of the properties of V1 for conscious phenomenology?
6) What are the visual pathways from the eyes to the brain, and its implication for blindsight?
The document discusses phi phenomena, which are optical illusions of motion perceived when viewing static images in rapid succession. It describes several types of illusions, including phi, motion pictures, and stroboscopic motion. Theories about how phi phenomena work include inference theory, which suggests the brain infers motion from sensory inputs based on past experience, and brain field theory, which proposes tensions in the brain motivate perceptions of whole objects and events. Phi phenomena led to significant research in visual perception and the founding of Gestalt psychology.
Optical illusions are visual perceptions that differ from objective reality due to processing in the brain. There are three main types - literal illusions create different images than objects, physiological illusions result from excessive stimulation overwhelming neural pathways, and cognitive illusions arise from unconscious inferences about the world. Factors causing illusions include color, eye structure, depth/distance, past experience, and lines/curves. Examples of natural illusions are rainbows, auroras, and mirages. Studying these failures of perception provides insight into the brain's visual processing.
The document discusses visual perception and how the brain processes visual information. It explains that perception is the process by which sensory impulses are organized and coded by the brain. Visual perception involves discriminating various visual attributes like color, shape, distance. It describes how visual impulses travel from the retina to the brain areas involved in visual processing and interpretation. Key areas mentioned are the optic chiasm, lateral geniculate nucleus, and primary visual cortex. The document also discusses factors that can influence perception like quality of vision, culture, drugs, personality, and observation methods. Finally, it introduces Gestalt principles of visual organization like figure-ground, similarity, proximity, continuity, closure, and simplicity.
It is one of the most viewed document from Pgblaster India website: Disorders of ocular motility with an emphasis on squint. In this document I have tried to give some important concepts of the different types of squints in simple words.At a glance, it is a much harder and complex topic of ophthalmology but I had made it as simpler as I could. Hope it will help you..
This document provides an overview of Chapter 5 from a psychology textbook, which discusses sensation and perception. It begins with key questions about how sensation and perception affect individuals and the specific senses. It then outlines the 14 study units that will be covered, focusing on vision, hearing, taste, smell, and touch. These study units describe the physical stimuli detected by sensory receptors in each sensory system, and how the brain processes this sensory information into perceptions. Thresholds, adaptation, depth perception, motion perception, and object constancy are some of the topics addressed.
Erik Ramsey suffered a traumatic brain injury in a car accident that left him "locked in" and unable to move or communicate, though he remained conscious and aware. Research has found evidence of consciousness in coma patients through similar patterns of brain activity between coma patients and non-coma patients. Consciousness arises from brain activity and can vary between fully awake, sleeping, in altered states such as hypnosis or meditation, or in flow experiences where people are fully immersed in an activity.
This study examined mirror neurons in macaque monkeys through electrophysiological recordings. The researchers recorded from 37 mirror neurons in the F5 region of the monkeys' brains. They found that mirror neurons responded both when the monkey performed hand actions like grasping and when they observed the experimenter perform the same actions. Mirror neurons responded more strongly during the late movement and holding periods of the observed actions. The results support the hypothesis that mirror neurons are involved in action recognition. The study provides evidence that mirror neurons encode the meaning and intention of observed actions.
This document provides an overview of sensation and perception. It defines sensation as the basic process of receiving sensory information, while perception involves interpreting that information. It discusses the sensory receptors and pathways for different senses. Key aspects of perception covered include thresholds, adaptation, attention, form perception, depth perception, movement perception, constancy, plasticity, and individual differences. Factors that can influence perception like the stimulus characteristics, context, and the individual are also summarized. The document is presented by Dr. Subodh Kumar Sharma on sensation and perception.
This document provides an overview of binocular vision including:
- Definitions of binocular vision as the use of both eyes together for vision and the perception of depth.
- The three grades of binocular vision: simultaneous perception, fusion, and stereopsis.
- Development of binocular vision occurs postnatally through the coordination and maturation of the visual pathways and cortex.
- Tests that are used to clinically investigate binocular vision abilities including retinal correspondence, suppression, fusion, and stereopsis.
Lies Our Brains Tell Us: Neuroscience and Sensory Perception!ShivekNarang
We will cover the basic human senses, and describe the basic neuroanatomy of how we process distinct signals in each modality. We also discuss vision and perception in depth. We look at many illusions!! Make sure to view the slides and see if these illusions are able to trick your mind :O. Your brain may end up playing tricks on itself by the end of the hour!
This document defines and classifies hallucinations, which are false sensory perceptions that occur without external stimuli. Hallucinations are categorized by sensory modality (auditory, visual, etc.), complexity, organization, and reality value. Neuroimaging research has found that auditory hallucinations are associated with reduced grey matter in language processing areas of the brain and altered connectivity between these areas and regions involved in control. Current models propose that hallucinations result from overactivity in sensory processing regions combined with weakened top-down control.
This document provides an introduction to binocular vision and ocular motility. It discusses the prerequisites for binocular single vision including overlapping visual fields and coordinated eye movements. It describes several theories of binocular vision such as the alternation theory and theory of isomorphism. Correspondence between retinal points and retinal disparity are also covered. The document outlines the neurophysiological basis of binocular vision involving binocular neurons in the visual cortex. It discusses normal development of binocular vision skills like fusion and stereopsis. Various types of abnormal binocular vision including suppression and amblyopia are also summarized. Finally, it defines important terminology related to ocular motility and eye movements.
Perception: definition, nature, importance, gestalt laws of grouping, bottoms up top down processing, perceptual process and perceptual constancy.
#psychology #perception #perceptualgrouping #perceptualconstancy
Consciousness & Neuroscience Francis Crick & Christof Kochnjqtpie86
The document discusses the work of Francis Crick and Christof Koch on understanding consciousness through neuroscience. They argue that consciousness can be studied scientifically by identifying the neuronal correlates of consciousness (NCC) - the minimal set of neuronal events and mechanisms sufficient for specific conscious experiences. They focus on visual consciousness, exploring visual representation and perception of bistable images. The document also briefly outlines the problems of qualia and meaning that were omitted from the paper's scope.
There are 6 extraocular muscles that control eye movement. The recti muscles rotate the eye in different directions while the oblique muscles cause torsional movement. Heterophoria is a latent misalignment of the eyes that is corrected by fusion. It can become manifest as a true strabismus. Comitant strabismus is when the eye deviation remains constant in all gazes, while incomitant strabismus involves restricted eye movement as well. Esotropia is inward eye turning and can be accommodative, non-accommodative, or secondary in nature.
Neural fields, a cognitive approach
- Neural fields model complex cognitive and behavioral functions as emerging from adaptive sensorimotor loops involving the external world, body, and brain (1 sentence)
- The model studies visual attention through mechanisms like saliency maps, inhibition of return, and the premotor theory of attention using neural fields (1 sentence)
- Decision making in the model is studied through the dynamics of neural fields modeling structures like the superior colliculus that encode saccade plans and make decisions about eye movement targets (1 sentence)
1. The brain constructs our visual field from electrical and chemical signals sent by the eyes to three separate pathways in the visual cortex. These pathways process shape, color, and object position/movement separately before combining them.
2. The eye does not function like a camera, as it does not capture an "image". Light stimulates the retina, sending signals to the brain, which must interpret the data to perceive vision.
3. Our perception of depth, motion and other qualities are inferences drawn from contrasts in light intensity, not direct visual data, yet we experience it as continuous vision. The brain adjusts and stabilizes our perception in ways that make the eye/camera analogy misleading.
Cognitive Neuroscience - Current Perspectives And Approaches Vivek Misra
Cognitive neuroscience is an academic field concerned with the scientific study of biological substrates underlying cognition, with a specific focus on the neural substrates of mental processes. It addresses the questions of how psychological/cognitive functions are produced by neural circuits in the brain.
In current slides, I tried to cover History, Basic Concepts and Research Methods currently used in cognitive neuroscience research.
Similar to 駒場学部講義 総合情報学特論III 「意識の科学的研究 - 盲視を起点に」 (20)
This document discusses using R and RStudio to simulate reinforcement learning models. It demonstrates simulating a Rescorla-Wagner model to update action values Q_A and Q_B based on payoffs from actions A and B over time. The model is expanded to select actions stochastically using a softmax function of the difference between Q_A and Q_B. Plots show the evolution of Q_A and Q_B over time for different learning rate and temperature parameters. The document provides an example code implementation of this reinforcement learning model in R.
Karl Fristonが提唱している「自由エネルギー原理(free-energy principle = FEP)」について、北大文学部の聴衆を対象にして、物理学や機械学習の知識の前提抜きにして、説明を行い、その意義を説明したものです。FEPの意識研究への応用に向けて、FEPとエナクション説の近接性について強調したものとなっております。
How to Setup Warehouse & Location in Odoo 17 InventoryCeline George
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
How to Manage Your Lost Opportunities in Odoo 17 CRMCeline George
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
Reimagining Your Library Space: How to Increase the Vibes in Your Library No ...Diana Rendina
Librarians are leading the way in creating future-ready citizens – now we need to update our spaces to match. In this session, attendees will get inspiration for transforming their library spaces. You’ll learn how to survey students and patrons, create a focus group, and use design thinking to brainstorm ideas for your space. We’ll discuss budget friendly ways to change your space as well as how to find funding. No matter where you’re at, you’ll find ideas for reimagining your space in this session.
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
A wound is a break in the integrity of the skin or tissues, which may be associated with disruption of the structure and function.
Healing is the body’s response to injury in an attempt to restore normal structure and functions.
Healing can occur in two ways: Regeneration and Repair
There are 4 phases of wound healing: hemostasis, inflammation, proliferation, and remodeling. This document also describes the mechanism of wound healing. Factors that affect healing include infection, uncontrolled diabetes, poor nutrition, age, anemia, the presence of foreign bodies, etc.
Complications of wound healing like infection, hyperpigmentation of scar, contractures, and keloid formation.
1. 東京大学学際科学科 2013年度 総合情報学特論III
意識の科学的研究 - 盲視を起点に
6月26日(水) 3-4限 13:00-16:20, 駒場キャンパス15号館1階104講義室
吉田 正俊 (自然科学研究機構・生理学研究所・認知行動発達研究部門 助教)
要旨 Part 1:
• The idea of two visual systems (cortical vs. subcortical) was confirmed in various animals.
• The dorsal and ventral visual pathways may have different roles on vision for action and vision for
perception, respectively.
• Feeling-of-something-happening in blindsight may be mediated by the dorsal pathway for saliency.
要旨 Part 2:
• Neural correlates of awareness can be studied using bistable percepts.
• Vision is not passive. Brain is predictive.
• Sensorimotor contingency explains our perception to some extent.
• The dorsal pathway for sensorimotor contingency and the ventral pathway for internal model?
• Current scientific study of consciousness is the study of philosophical zombie.
• Neurophenomenology tries to establish a first-person methodology but it is not successful yet.
PART 1
0. What is consciousness?
-- Let’s start from examples
• Salient visual stimuli can disappear.
• We are not conscious of all of the signals on the
retina.
1. What is Blindsight (盲視)?
• Q: What is blindsight?
• A: “The visually evoked voluntary responses of
patients with striate cortical destruction that are
demonstrated despite a phenomenal blindness”
1
• Phenomenal consciousness can be dissociated
from visual information processing.
2. Two visual systems:
Cortical vs. Subcortical
2-1. Two visual systems in monkeys
• Bilateral lesion in V1 - first report of blindsight in
monkey
2
• Retained: visually guided reaching and obstacle
avoidance
3
2-2. Two visual systems in rodents
• Double dissociation - lesion in visual cortex and in
the superior colliculus
4
• SC for orienting
5
• Visual cortex for pattern discrimination
6
2-3. Two visual systems in frogs
• Two Visual Systems in the Frog
7
• Lesion in the optic tectum induces rewiring.
• Neocortex for obstacle avoidance
• Optic tectum for Response to preys
3. Two cortical visual systems:
Dorsal vs. Ventral
3-1. What and where pathways (Mishkin &
Ungerleider)
• The neurons in the dorsal pathway are selective to
motion and binocular disparity.
• The neurons in the ventral pathway are selective to
shape and color.
8
• Bilateral removal of area TE: Object discrimination -
Which is the unfamiliar object?
• Bilateral removal of posterior parietal cortex:
Landmark discrimination - Which is near to the
landmark?
9
3-2. Vision for perception and vision for action
(Goodale and Milner)
• Dorsal pathway: Vision for action
• Ventral pathway: Vision for perception
10
• Optic ataxia (視覚性運動失調)
• Damage in the posterior parietal cortex -
supramarginal gyrus and angular gyrus
• Orientation error does not depend on hand but on
visual field.
• Damage in the dorsal pathway affects vision for
2. action.
11
• Visual form agnosia (視覚失認):
• Subject DF: Bilateral damage in ventral visual
pathway (Lateral occipital area: LO)
• Very good performance in ‘posting’ task
12
• DF matched her card orientation to the slot during
the course of the movement, well before
contacting the target.
13
• Functional double dissociation
• "Visual phenomenology ... can arise only from
processing in the ventral stream ...
visual-processing modules in the dorsal stream ...
are not normally available to awareness." ("The
visual brain in action" p.200-201)
14
3-3. Perceptual experience in visual agnosia
• Retained color, texture perception
• Degraded form perception
• a piece of kitchen equipment … it’s got a red part
to it, a red handle … it goes down into a silver
corrugated part … the red part’s plastic and the
other part’s metal.” (When she was handed it) “Oh,
it’s a torch.”
15
• She had difficulty in describing her visual
experience, only saying that objects tend to appear
‘blurred’ and that separate elements ‘run into each
other’.
13
4. Blindsight in human
4-1. Case reports
• G.Y. became blind in his right visual field due to
traffic accident in eight years old. He was
diagnosed as homonymous hemianopia.
• Above-chance performance in forced-choice =>
blindsight
16
4-2. Blindsight and two-visual systems
hypothesis
• Access to the dorsal pathway in blindsight
5. Blindsight in monkey
5-1. Blindsight in monkeys
• Blindsight after 2-3 months training
17
• Are the monkeys really ‘blind’ to the visual stimuli?
The monkeys behaved as if it is a No-target trial.
The monkeys are ‘not able to see’, as in human
blindsight.
5-2. Saliency in blindsight
• Monkey without V1: Visually guided reaching
• Frogs with rewired OT: Frogs with rewired OT
• => Visual saliency?
• What is saliency?
• Saliency computational model
18
• Salient stimuli attract gazes of blindsight monkeys
19
• The gaze positions have higher saliency, than
expected from random eye movement.
• What it is like to be blindsight?
• feeling ‘atmosphere’ = saliency without visual
consciousness
• Dual system for conscious vision and saliency.
6. Summary
PART 2
1. How to study consciousness?
1-1 Definition of consciousness
• ?? “Consciousness is not a subject of science
because we cannot define them.”
• Let’s start from a common-sense definition, not
from an analytic definition.
20
• A common-sense definition of consciousness:
"consciousness refers to those states of sentience
or awareness that typically begin when we wake
from a dreamless sleep and continue through the
day …”
1-2 Hard problem of consciousness
• Philosophical zombie
• The inverted spectrum
• * How things that look green to you look red to me
and vice versa.
• * The things we both call red look to you the way
the things we both call green look to me.
• In his (Ned’s) class, ~2/3 of the students usually
say, ‘Oh yeah, I see what you’re talking about’ and
some of them even say, ‘Oh yeah, I’ve wondered
about that since I was a kid.’ ~1/3 of people say, ‘I
don’t know what you’re talking about.’
• The hard problem of consciousness:
• the problem of explaining how and why we have
qualia or phenomenal experiences — how
sensations acquire characteristics, such as colors
and tastes.
• Awareness: “a state wherein we have access to
some information, and can use that information in
the control of behavior.” the psychological concept
of mind”
1-3 Neural correlates of awareness
• An experimental manipulation is required by which
a visual input is constant but perception of that
visual stimulus varies.
• In binocular rivalry, the stimulus is stable but the
content of awareness switches. Then, we can find
the neural correlate of visual awareness by
comparing two different perceptual reports.
• Activity of IT neurons reflects the monkeys’
perceptual report
21
. This is strong evidence that IT
neurons represent content of subjective
experience.
• fMRI during binocular rivalry
22
3. 2. Active vision
2-1 Corollary discharge and Remapping
• We reconstruct images by constantly moving our
eyes.
23,24
• Corollary discharge
• Helmholtz (1866)
• why image motion caused by saccades passes
unnoticed
• Why stability is maintained in spite of shifts in
image position
• Efferent copy (Von Holst and Mittelstaedt 1954)
• Keeping track of one's movements was based on
monitoring outputs to muscles (implication of
exact copy)
• Corollary discharge (Sperry 1950)
• The interaction of "motor patterns" with a
"sensorium" without specifying where the
interaction occurs
• Why can’t you tickle yourself? - Cancellation of
self-produced sensation
• Stability of vision during saccade
• Pre-saccadic remapping in LIP
2-2 Bayesian surprise
• How to evaluate temporal saliency?
• Saliency model evaluates what is salient in an
image in term of spatial configuration.
• How to evaluate what is salient in an image in term
of temporal changes? => Bayesian surprise
• You have a belief about the world: “it is the CNN
news.”
• We get surprised if we have to change our belief of
the world.
• The world becomes boring again.
• Bayesian surprise measures how much your belief
changed by the data.
• Bayesian surprise is defined as the difference
between prior and posterior. =>KL divergence
• Surprise is better predictor than saliency
2-3 Friston’s free energy principle
• The free-energy principle
25
• An organism is able to minimize the free energy by
reducing bayesian surprise (internal state) or by
changing sensation (action).
3. Enactive view
3-1 Sensorimotor contingency theory
• Standard view: Seeing is making an internal
representation
• New view: Seeing is knowing about things to do
26
• Alva Noe のエナクション説
27
:
• Sensorimotor dependence: 私たちが対象に向かっ
て近づくと対象の姿が大きくなる。
• 私たちはこのような sensorimotor dependence に
精通している。
• 私たちの知覚能力は、この種の感覚-運動的知識の
所有によって構成されている。
• 感覚-運動的知識とは命題的なものではなくて、技
能的なもの。(宣言的記憶と手続き記憶)
• 例:開眼手術、逆さメガネ
3-2 Brain or environment, which determines
conscious experience?
• Blindsight = Frog’s consciousness?
• This is an ‘internalist’ view. Brain area determines
which kind of experience is evoked.
• Hurley and Noë’s argument:
28
• Based on Enactive view, sensorimotor contingency,
rather than brain region, is the determinant of
conscious experience.
• This is empirically testable. sensory input ? (=>
Externalism, enactivism) or brain activity? (=>
Internalism)
• Phantom limb: the case for brain activity
• Inverted glass: the case for sensory input
29
• Which occurs in blindsight?
• Internalist view: ‘Feeling of something happening’
is a result of SC activity but it is overridden by
‘redness of red’ in normal subjects. After V1
lesion, it was unmasked.
• Enactive view: ‘Feeling of something happening’
can be a kind of conscious experience
accompanied by functional recovery and
expanded availability of sensorimotor skill.
• 盲視の例は externalist 説を支持しているのではな
いか?
• 1) Please remember blindsight is not available
just after the lesion.
• 2) さらに empirical にテストできる。Normal
subject で V1 を一時的に suppress したら
feeling-of-something は起こるか? 盲視で SC を
一時的に抑えたら何が起こるか?
4. Let’s combine everything
Dorsal: ‘Feeling-of-something-happening’ is shaped
by sensorimotor contingency.
Decision is not consciousness. Evidence
accumulation and action are the same in term of
“active inference”.
Ventral: Conscious experience emerges as an
internal model in predictive coding.
Bottom up attention (or surprise) and consciousness
is the same when they have no prediction error.
5. Hetero-phenomenology (ヘテロ現象学)
•
• Q: How to study consciousness scientifically?
• A (by Dennett): Do it with heterophenomenology.
• 火星から来た科学者(哲学的ゾンビ)が地球人の「意
識経験」について調査しているとする。
4. • 火星人は行動データ、生理データを集める。
• 行動データのうち、言語報告やボタン押しについて
は信念や意図を表しているものとして解釈する
(志向的態度)。
30
• 火星人はこれらのデータから、地球人の意識経験を
フィクションとして再構成する。
• 火星人は地球人の意識経験が実在するかどうかを
問わなくてよいという意味で中立的であると言え
る。
• これは文化人類学者がある部族の宗教を研究する
のに、その宗教を信じなくてもよいのと同じだ。
• この方法は科学の厳密さを失うことを最小限にし
た、意識の三人称的研究法であると言える。
31
• そしてこれこそが現在の実験心理学、認知神経科学
が行っていることそのものである。
• 両眼視野闘争の例
22
• (a) 「顔を見たという意識経験そのもの」
• (b) その意識経験を持ったという信念
• (c) その信念を表出するためにボタンの右を選択
する
• (d) 右ボタンを押す(=「顔を見た」と発声する)
• ヘテロ現象学では(d)という一次データを解釈する
ことで(b)という信念(志向的態度)に到達する。
• どうやって(b)という信念が生まれたかを解明する
ことが意識の科学がするべきこと。
• (a)そのものは問わない。
• もし(a)=(b)でないのなら、(b)に「被験者は言い表
せない信念を持っている」という信念を付け加えれ
ばよい。
6. Neurophenomenology (神経現象学)
• 「意識のハードプロブレムに対する方法論的救済
策」
32
• 意識経験を一人称的かつ誰でも同意できる形で説
明するにはどうすればよいか?
• 三つの統合
• 1) 意識経験の(フッサール)現象学的な分析
• 2) 生物学的システムに関する経験的な実験
• 3) 力学系理論
• なんで力学系か?:
• enactive な認知観:認知は身体を持つ(embodied)
エージェントによって行われ、感覚・運動的活動
によって媒介される。
• => enactive な認知は力学系的な道具立ての中に
自然に収まる (<==> 計算論的)
33
• 現象学的な時間(「生きられた時間」=把持、原印
象、予持)は内部発生的な力学系の中で協調してい
る (=> trajectory によって決まる)
• 神経現象学の実践例:
34
• 1) 被験者は「現象学的還元」によって、事項が経
験される仕方に注目するように訓練する。
• 現象学的還元 = 「主観と客観」の二元論のよう
な形而上学をいったん脇に置いて経験の構造を
反省的に捉えること
• => 現象学的方法は内観主義ではない
• 1)「現象学的還元」の成果として、被験者は発見的
に自分の準備状態について報告できるようになっ
た。このカテゴリーが他の被験者と一貫しているこ
とを確認した。(「相互主観的な確証」)
• 2) 多点での EEG(脳波)の計測
• 3) 力学系的な方法での解析: 試行を平均化しない
ガンマ帯の脳波の phase synchronization
• 現象学的に明らかにされた準備状態によって脳波
の phase synchrony が変わる。
• My criticism:
• 1) 意識状態について「発見的にカテゴリー分け
をする」点以外はヘテロ現象学と違いはない。両
眼視野闘争実験でだって、経験を整理していく際
に「右、左、両方が混ざる」というカテゴリー分
けが出来て、それは被験者に依らず共通。
• 2) 結局のところ「神経相関」であって、力学系
的な「内的に区別可能なカテゴリーの創発」とは
なっていない。
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