The document summarizes somatic sensations and the somatosensory system. It describes:
1) The general organization of the somatosensory system including receptors, pathways to the brain, and processing of sensations. Mechanoreceptors, nociceptors, and thermoreceptors are discussed.
2) Classification of somatic sensations based on function, stimulus, and location. Tactile sensations are subdivided based on the specific receptors.
3) Pathways for transmitting sensory information including the dorsal column-medial lemniscal system and anterolateral system.
4) Organization of the somatosensory cortex and somatosensory homunculus representation of the body.
The sensory system enables perception of changes in the external and internal environment through three departments - peripheral, conducting, and central. The peripheral department contains receptors that code information and perform primary analysis. The conducting department conveys impulses to the cortex and performs secondary analysis through reflexes. The central/cortex department enables higher-level analyses and perceptions. Receptors are classified based on their mechanism, location, stimulus type, and sensations caused. Coding of information in receptors uses a binary code to represent parameters like force, duration, and thresholds of sensitivity.
Nerve fibers can be classified based on their structure and distribution. There are two main types - myelinated and unmyelinated fibers. Nerve fibers also include somatic and autonomic fibers. Somatic fibers innervate skeletal muscles and the neurotransmitter is acetylcholine, leading to muscle excitation or central inhibition. Autonomic fibers innervate smooth, cardiac muscles and glands to maintain homeostasis, causing excitation or inhibition. Important properties of nerve fibers include excitability, conductivity, unfatigability, refractory periods, all-or-none response, summation, and accommodation.
The document summarizes sensory physiology, including the structure and function of sensory receptors and neural pathways. It discusses how different sensory receptors transduce various stimuli like touch, temperature, sound, and light into nerve impulses. The receptors are categorized based on their modality and location. The pathways from receptors to the central nervous system are described for each sensory system. Adaptation and processing of sensory information in the brain is also overviewed.
Sensory receptors detect stimuli from the internal and external environment and transmit this information to the central nervous system via sensory neurons. There are several types of sensory receptors that detect different modalities like touch, pressure, vibration, temperature, and pain. Mechanoreceptors include receptors that detect touch and pressure like free nerve endings, Meissner's corpuscles, Merkel's discs, hair receptors, Ruffini endings, and Pacinian corpuscles. Tactile signals are transmitted via myelinated A-beta fibers while pain and itch signals use small diameter C fibers. The dorsal column medial lemniscus pathway transmits tactile, proprioceptive, and vibratory signals from the periphery to the thalamus and som
This document summarizes the action potential in neurons. It describes how an action potential is initiated by voltage-gated sodium channels opening during depolarization. This allows sodium ions to rush into the neuron, further depolarizing the membrane. Then, the sodium channels quickly inactivate while voltage-gated potassium channels open, allowing potassium ions to leave the neuron and repolarize the membrane back to its resting potential. The precise opening and closing of sodium and potassium channels underlies the generation and propagation of action potentials along neuronal membranes.
The basal ganglia consist of several structures including the caudate nucleus, putamen, globus pallidus, substantia nigra, and subthalamic nucleus. They are located within the cerebral hemispheres and are involved in motor control and cognition. Two main circuits exist - the putamen circuit for executing movements and the caudate circuit for cognitive motor control. Diseases that impact the basal ganglia like Parkinson's and Huntington's result from dysfunction of neurotransmitter pathways and can cause both hyperkinetic and hypokinetic movement disorders. Common treatments involve replacing dopamine or modifying basal ganglia circuitry.
Neurons transmit signals through structures called synapses. There are two main types of synapses - chemical and electrical. In a chemical synapse, signals pass via neurotransmitter molecules released by the presynaptic neuron into the synaptic cleft. This can cause an excitatory postsynaptic potential in the postsynaptic neuron. Electrical synapses allow direct ion flow between neurons through gap junctions, allowing faster signal transmission but in both directions. Neurons are classified based on their structure and function, with motor neurons carrying signals from the CNS to effectors and sensory neurons carrying signals to the CNS.
The sensory system enables perception of changes in the external and internal environment through three departments - peripheral, conducting, and central. The peripheral department contains receptors that code information and perform primary analysis. The conducting department conveys impulses to the cortex and performs secondary analysis through reflexes. The central/cortex department enables higher-level analyses and perceptions. Receptors are classified based on their mechanism, location, stimulus type, and sensations caused. Coding of information in receptors uses a binary code to represent parameters like force, duration, and thresholds of sensitivity.
Nerve fibers can be classified based on their structure and distribution. There are two main types - myelinated and unmyelinated fibers. Nerve fibers also include somatic and autonomic fibers. Somatic fibers innervate skeletal muscles and the neurotransmitter is acetylcholine, leading to muscle excitation or central inhibition. Autonomic fibers innervate smooth, cardiac muscles and glands to maintain homeostasis, causing excitation or inhibition. Important properties of nerve fibers include excitability, conductivity, unfatigability, refractory periods, all-or-none response, summation, and accommodation.
The document summarizes sensory physiology, including the structure and function of sensory receptors and neural pathways. It discusses how different sensory receptors transduce various stimuli like touch, temperature, sound, and light into nerve impulses. The receptors are categorized based on their modality and location. The pathways from receptors to the central nervous system are described for each sensory system. Adaptation and processing of sensory information in the brain is also overviewed.
Sensory receptors detect stimuli from the internal and external environment and transmit this information to the central nervous system via sensory neurons. There are several types of sensory receptors that detect different modalities like touch, pressure, vibration, temperature, and pain. Mechanoreceptors include receptors that detect touch and pressure like free nerve endings, Meissner's corpuscles, Merkel's discs, hair receptors, Ruffini endings, and Pacinian corpuscles. Tactile signals are transmitted via myelinated A-beta fibers while pain and itch signals use small diameter C fibers. The dorsal column medial lemniscus pathway transmits tactile, proprioceptive, and vibratory signals from the periphery to the thalamus and som
This document summarizes the action potential in neurons. It describes how an action potential is initiated by voltage-gated sodium channels opening during depolarization. This allows sodium ions to rush into the neuron, further depolarizing the membrane. Then, the sodium channels quickly inactivate while voltage-gated potassium channels open, allowing potassium ions to leave the neuron and repolarize the membrane back to its resting potential. The precise opening and closing of sodium and potassium channels underlies the generation and propagation of action potentials along neuronal membranes.
The basal ganglia consist of several structures including the caudate nucleus, putamen, globus pallidus, substantia nigra, and subthalamic nucleus. They are located within the cerebral hemispheres and are involved in motor control and cognition. Two main circuits exist - the putamen circuit for executing movements and the caudate circuit for cognitive motor control. Diseases that impact the basal ganglia like Parkinson's and Huntington's result from dysfunction of neurotransmitter pathways and can cause both hyperkinetic and hypokinetic movement disorders. Common treatments involve replacing dopamine or modifying basal ganglia circuitry.
Neurons transmit signals through structures called synapses. There are two main types of synapses - chemical and electrical. In a chemical synapse, signals pass via neurotransmitter molecules released by the presynaptic neuron into the synaptic cleft. This can cause an excitatory postsynaptic potential in the postsynaptic neuron. Electrical synapses allow direct ion flow between neurons through gap junctions, allowing faster signal transmission but in both directions. Neurons are classified based on their structure and function, with motor neurons carrying signals from the CNS to effectors and sensory neurons carrying signals to the CNS.
This document discusses the regulation of respiration. It covers the neural, automatic, and chemical control mechanisms that regulate breathing. The key points are:
1) Respiration is regulated by medullary and pontine respiratory centers in the brainstem that generate the breathing rhythm and control rate and depth.
2) Breathing is also automatically controlled and can occur without conscious effort. It is further modulated by inputs from chemoreceptors sensitive to oxygen, carbon dioxide, and pH levels in the blood.
3) Peripheral chemoreceptors located in the carotid bodies and aortic bodies detect changes in blood gases and signal the respiratory centers to adjust breathing accordingly. Central chemoreceptors in the brainstem are
The document discusses sensory perception and the role of receptors. It describes the basic process of stimulus reception, transduction, and transmission via receptors and sensory neurons. It classifies receptors by structure, location, modality, and adaptation properties. Receptors convert stimuli into receptor potentials, which may generate action potentials. Rapidly adapting receptors signal changes in stimuli while slowly adapting receptors signal sustained stimuli.
This document discusses the physiology of the spinal cord, including spinal cord reflexes and tracts. It describes:
1. Different types of reflexes in the spinal cord like somatic, vegetative, stretching, flexion, and extension reflexes. Tendon reflexes like the Achilles reflex and knee jerk reflex are also discussed.
2. Ascending and descending tracts in the spinal cord, including direct and crossed tracts for tactile and proprioceptive sensitivity.
3. Spinal cord reflexes and their effects like muscle protection, standing, walking, and removal of excitatory stimuli.
The document discusses the ascending tracts and posterior column pathway in the spinal cord. It provides details on:
1) The medial lemniscus system carries sensations for fine touch, pressure, and vibration from receptors through the dorsal roots and fasciculus gracilis and cuneatus tracts in the spinal cord.
2) Fibers from the tracts synapse in the medulla and cross over before ascending to the thalamus and primary sensory cortex.
3) The posterior column pathway conveys proprioception, vibration, discriminative touch, weight discrimination and stereognosis signals up the spinal cord within the posterior column tracts.
Sensory receptors convert different types of energy like touch, pressure, heat, and light into electrical signals that are transmitted to the central nervous system. There are several classes of sensory receptors including mechanoreceptors, nociceptors, chemoreceptors, and photoreceptors. The somatosensory system contains mechanoreceptors that detect touch, vibration, and proprioception. Sensory information is coded by modality, location, intensity and duration. Laws of specific nerve energies and projection state that sensation is determined by the receptor and referred to its location. Clinical tests of vibration sense and stereognosis examine somatosensory function.
Here are the answers to your questions:
1a) A transection on the left side at T4 would impair fine touch, proprioception and vibration sense on the right side of the body below the level of the lesion.
1b) A transection on the left side at T4 would impair pain, temperature and crude touch sensation on the left side of the body below the level of the lesion.
2) In response to an increase in temperature from 35oC to 40oC: Cold receptors would increase their firing rate initially but then adapt to the new temperature. Warm receptors would increase their firing rate initially and maintain an elevated firing rate as long as the temperature is sustained at 40oC. Both receptor
The cerebellum is located behind the brainstem and contains only 10% of the brain's volume. It receives input from muscles, joints, and the motor cortex, and provides corrective signals to the motor cortex to coordinate voluntary movement. The cerebellum evaluates and adjusts motor movements, integrating sensory information to ensure balance and motor learning. Damage to different parts of the cerebellum results in difficulties with coordination, posture, movement timing and sequencing.
1. There are 3 major somatic sensory pathways - the posterior column pathway, spinothalamic pathway, and spinocerebellar pathway.
2. The posterior column pathway carries sensations of fine touch, pressure, vibration, and proprioception. The spinothalamic pathway carries crude touch, pressure, pain, and temperature sensations. The spinocerebellar pathway sends proprioceptive information to the cerebellum.
3. There are also 3 major motor pathways - the corticospinal pathway for voluntary movement, the medial pathway for trunk and limb muscle tone/movement, and the lateral pathway for distal limb movement. These pathways involve upper and lower motor neurons to control skeletal muscles.
Generation and conduction of action potentialsCsilla Egri
This document provides an overview of action potentials and nerve conduction. It discusses synaptic transmission through both electrical and chemical synapses. It then covers the major classes of neurotransmitters and neurotransmitter receptors. The document reviews graded potentials, spatial and temporal summation, and electrotonic conduction. It describes the ionic basis and phases of the action potential as well as how action potentials propagate along axons. Finally, it discusses nerve conduction disorders like demyelination and multiple sclerosis.
The document summarizes the human sensory system. It describes the general senses associated with skin, muscles, and organs, as well as the special senses located in the head like eyes, ears, nose and mouth. It then discusses sensory receptors that detect stimuli and transmit signals to the brain, as well as the sensations and perceptions that result. Different receptor types respond to stimuli like chemicals, pain, temperature, and mechanical forces. The pathways and processing of sensory signals in the central nervous system are also outlined.
The reticular formation is a network of neurons located in the brainstem that serves several important functions:
1. It helps regulate arousal and consciousness through the reticular activating system. This system projects to the thalamus and maintains an alert cerebral cortex. Damage can result in coma.
2. It modulates muscle tone through facilitatory and inhibitory projections to the spinal cord. The pontine reticular formation facilitates antigravity muscles while the medullary region inhibits them.
3. In addition to arousal and motor control, the reticular formation is involved in other autonomic functions like respiration, cardiovascular regulation, vomiting, coughing, and processing pain signals.
The sensory system is the part of the nervous system that detects ,transfers and processes stimuli from the environment
http://www.asktheneurologist.com/Sensory-System.html
This document summarizes the key components of the human sensory system. It describes how sensory information is received by receptors, transmitted through neurons in the peripheral and central nervous systems, and integrated and processed in the brain. Specifically, it discusses:
1) The pathways for different sensory modalities from receptors to the spinal cord and brain, including pain/temperature, touch, and proprioception.
2) The ascending tracts that transmit sensory information from the spinal cord to the brain, such as the lateral spinothalamic, anterior spinothalamic, and posterior columns.
3) Common lesions that affect sensory pathways and how they impact sensation, such as hemisection of the spinal cord or damage to
The somatosensory cortex is located on the postcentral gyrus in the parietal lobe behind the primary motor cortex. It is involved in somatic sensation, visual stimuli, and movement planning, with different body regions represented across the cortex. The primary somatosensory cortex processes basic sensation while the secondary somatosensory cortex serves as an association area involved in higher functions like memory, spatial processing, and consciousness.
The resting membrane potential (RMP) refers to the stable voltage difference between the inside and outside of a cell membrane when the cell is not actively transmitting signals. The RMP results from selective permeability of ions like potassium and sodium across the membrane. At rest, the neuron's RMP is approximately -70mV due to higher intracellular potassium concentration creating a diffusion potential of -94mV, and lower intracellular sodium contributing +61mV. Additional contribution from the sodium-potassium pump, which actively transports ions against their gradients, results in the overall RMP of -90mV in neurons.
The document describes the major descending pathways from the brain to the spinal cord that control motor function. These include the direct corticospinal tract and indirect extrapyramidal tracts such as the rubrospinal, tectospinal, and vestibulospinal tracts. It provides details on the origin, pathways, and termination of the corticospinal tract, which originates in the motor cortex, passes through the internal capsule and brainstem, and terminates on anterior horn cells of the spinal cord.
This document summarizes the somatosensory system and receptors. It describes the different types of sensation including superficial, deep, visceral, and special. It outlines the categories of conscious and non-conscious sensation. It discusses the different receptors including exteroceptors, proprioceptors, and intteroceptors. It details the nerve endings including free nerve endings, follicular nerve endings, Merkel cell neurite complexes, encapsulated endings like Meissner's corpuscles and Pacinian corpuscles. It outlines the somatosensory pathways including the posterior column-medial lemniscal pathway and spinothalamic pathway.
This document discusses the senses of smell (olfaction) and taste. It notes that smell and taste have a cooperative relationship, with odor contributing approximately 80% of what we perceive as flavor. The main points covered include:
- Smell and taste are classified as special senses along with sight, hearing, and balance
- The olfactory system includes receptors in the nose, olfactory bulbs, and pathways to the brain regions involved in emotion and behavior
- Pheromones influence behaviors through a vomeronasal system present in many animals
- Humans have a less developed sense of smell compared to most animals
- The olfactory epithelium regenerates sensory neurons throughout life but this capacity declines with age
The document summarizes the neural and chemical regulation of respiration. It describes the key respiratory centers in the medulla and pons that control breathing. These include the dorsal and ventral respiratory groups in the medulla and the apneustic and pneumotaxic centers in the pons. Peripheral chemoreceptors in the carotid body and aortic body and central chemoreceptors in the medulla detect changes in blood gases like CO2 and pH to modulate breathing. Increased CO2 and H+ stimulate these chemoreceptors to enhance the activity of the respiratory centers and increase ventilation.
Somatic mechanoceptive sensation.hussein f. sakrHussein Sakr
This document defines and describes different types of sensation, including somatic, visceral, and special sensations. It focuses on somatic sensation, which is initiated by receptors in the skin, muscles, bones and joints. Somatic sensation includes tactile sensations like touch and pressure, thermal sensations, and pain sensation. It discusses the receptors involved and pathways for transmitting different types of somatic sensation, including the dorsal column medial lemniscus system and anterolateral system. Proprioceptive sensation and vibration sense are also defined and their receptors and pathways described.
The somatosensory system allows humans to recognize objects, textures, and social cues through networks of neurons. It produces perceptions of touch, temperature, body position, and pain. Sensory receptors collect information and stimulate neurons to send impulses to the brain. There are different types of sensations including superficial touch and pain, deep proprioception and vibration, and visceral sensations like hunger. The somatosensory system includes exteroceptive senses on the skin, visceroceptive senses in the viscera, and proprioceptive senses in the muscles and joints. Sensory impulses are transmitted through peripheral nerves to the central nervous system to be analyzed and interpreted.
This document discusses the regulation of respiration. It covers the neural, automatic, and chemical control mechanisms that regulate breathing. The key points are:
1) Respiration is regulated by medullary and pontine respiratory centers in the brainstem that generate the breathing rhythm and control rate and depth.
2) Breathing is also automatically controlled and can occur without conscious effort. It is further modulated by inputs from chemoreceptors sensitive to oxygen, carbon dioxide, and pH levels in the blood.
3) Peripheral chemoreceptors located in the carotid bodies and aortic bodies detect changes in blood gases and signal the respiratory centers to adjust breathing accordingly. Central chemoreceptors in the brainstem are
The document discusses sensory perception and the role of receptors. It describes the basic process of stimulus reception, transduction, and transmission via receptors and sensory neurons. It classifies receptors by structure, location, modality, and adaptation properties. Receptors convert stimuli into receptor potentials, which may generate action potentials. Rapidly adapting receptors signal changes in stimuli while slowly adapting receptors signal sustained stimuli.
This document discusses the physiology of the spinal cord, including spinal cord reflexes and tracts. It describes:
1. Different types of reflexes in the spinal cord like somatic, vegetative, stretching, flexion, and extension reflexes. Tendon reflexes like the Achilles reflex and knee jerk reflex are also discussed.
2. Ascending and descending tracts in the spinal cord, including direct and crossed tracts for tactile and proprioceptive sensitivity.
3. Spinal cord reflexes and their effects like muscle protection, standing, walking, and removal of excitatory stimuli.
The document discusses the ascending tracts and posterior column pathway in the spinal cord. It provides details on:
1) The medial lemniscus system carries sensations for fine touch, pressure, and vibration from receptors through the dorsal roots and fasciculus gracilis and cuneatus tracts in the spinal cord.
2) Fibers from the tracts synapse in the medulla and cross over before ascending to the thalamus and primary sensory cortex.
3) The posterior column pathway conveys proprioception, vibration, discriminative touch, weight discrimination and stereognosis signals up the spinal cord within the posterior column tracts.
Sensory receptors convert different types of energy like touch, pressure, heat, and light into electrical signals that are transmitted to the central nervous system. There are several classes of sensory receptors including mechanoreceptors, nociceptors, chemoreceptors, and photoreceptors. The somatosensory system contains mechanoreceptors that detect touch, vibration, and proprioception. Sensory information is coded by modality, location, intensity and duration. Laws of specific nerve energies and projection state that sensation is determined by the receptor and referred to its location. Clinical tests of vibration sense and stereognosis examine somatosensory function.
Here are the answers to your questions:
1a) A transection on the left side at T4 would impair fine touch, proprioception and vibration sense on the right side of the body below the level of the lesion.
1b) A transection on the left side at T4 would impair pain, temperature and crude touch sensation on the left side of the body below the level of the lesion.
2) In response to an increase in temperature from 35oC to 40oC: Cold receptors would increase their firing rate initially but then adapt to the new temperature. Warm receptors would increase their firing rate initially and maintain an elevated firing rate as long as the temperature is sustained at 40oC. Both receptor
The cerebellum is located behind the brainstem and contains only 10% of the brain's volume. It receives input from muscles, joints, and the motor cortex, and provides corrective signals to the motor cortex to coordinate voluntary movement. The cerebellum evaluates and adjusts motor movements, integrating sensory information to ensure balance and motor learning. Damage to different parts of the cerebellum results in difficulties with coordination, posture, movement timing and sequencing.
1. There are 3 major somatic sensory pathways - the posterior column pathway, spinothalamic pathway, and spinocerebellar pathway.
2. The posterior column pathway carries sensations of fine touch, pressure, vibration, and proprioception. The spinothalamic pathway carries crude touch, pressure, pain, and temperature sensations. The spinocerebellar pathway sends proprioceptive information to the cerebellum.
3. There are also 3 major motor pathways - the corticospinal pathway for voluntary movement, the medial pathway for trunk and limb muscle tone/movement, and the lateral pathway for distal limb movement. These pathways involve upper and lower motor neurons to control skeletal muscles.
Generation and conduction of action potentialsCsilla Egri
This document provides an overview of action potentials and nerve conduction. It discusses synaptic transmission through both electrical and chemical synapses. It then covers the major classes of neurotransmitters and neurotransmitter receptors. The document reviews graded potentials, spatial and temporal summation, and electrotonic conduction. It describes the ionic basis and phases of the action potential as well as how action potentials propagate along axons. Finally, it discusses nerve conduction disorders like demyelination and multiple sclerosis.
The document summarizes the human sensory system. It describes the general senses associated with skin, muscles, and organs, as well as the special senses located in the head like eyes, ears, nose and mouth. It then discusses sensory receptors that detect stimuli and transmit signals to the brain, as well as the sensations and perceptions that result. Different receptor types respond to stimuli like chemicals, pain, temperature, and mechanical forces. The pathways and processing of sensory signals in the central nervous system are also outlined.
The reticular formation is a network of neurons located in the brainstem that serves several important functions:
1. It helps regulate arousal and consciousness through the reticular activating system. This system projects to the thalamus and maintains an alert cerebral cortex. Damage can result in coma.
2. It modulates muscle tone through facilitatory and inhibitory projections to the spinal cord. The pontine reticular formation facilitates antigravity muscles while the medullary region inhibits them.
3. In addition to arousal and motor control, the reticular formation is involved in other autonomic functions like respiration, cardiovascular regulation, vomiting, coughing, and processing pain signals.
The sensory system is the part of the nervous system that detects ,transfers and processes stimuli from the environment
http://www.asktheneurologist.com/Sensory-System.html
This document summarizes the key components of the human sensory system. It describes how sensory information is received by receptors, transmitted through neurons in the peripheral and central nervous systems, and integrated and processed in the brain. Specifically, it discusses:
1) The pathways for different sensory modalities from receptors to the spinal cord and brain, including pain/temperature, touch, and proprioception.
2) The ascending tracts that transmit sensory information from the spinal cord to the brain, such as the lateral spinothalamic, anterior spinothalamic, and posterior columns.
3) Common lesions that affect sensory pathways and how they impact sensation, such as hemisection of the spinal cord or damage to
The somatosensory cortex is located on the postcentral gyrus in the parietal lobe behind the primary motor cortex. It is involved in somatic sensation, visual stimuli, and movement planning, with different body regions represented across the cortex. The primary somatosensory cortex processes basic sensation while the secondary somatosensory cortex serves as an association area involved in higher functions like memory, spatial processing, and consciousness.
The resting membrane potential (RMP) refers to the stable voltage difference between the inside and outside of a cell membrane when the cell is not actively transmitting signals. The RMP results from selective permeability of ions like potassium and sodium across the membrane. At rest, the neuron's RMP is approximately -70mV due to higher intracellular potassium concentration creating a diffusion potential of -94mV, and lower intracellular sodium contributing +61mV. Additional contribution from the sodium-potassium pump, which actively transports ions against their gradients, results in the overall RMP of -90mV in neurons.
The document describes the major descending pathways from the brain to the spinal cord that control motor function. These include the direct corticospinal tract and indirect extrapyramidal tracts such as the rubrospinal, tectospinal, and vestibulospinal tracts. It provides details on the origin, pathways, and termination of the corticospinal tract, which originates in the motor cortex, passes through the internal capsule and brainstem, and terminates on anterior horn cells of the spinal cord.
This document summarizes the somatosensory system and receptors. It describes the different types of sensation including superficial, deep, visceral, and special. It outlines the categories of conscious and non-conscious sensation. It discusses the different receptors including exteroceptors, proprioceptors, and intteroceptors. It details the nerve endings including free nerve endings, follicular nerve endings, Merkel cell neurite complexes, encapsulated endings like Meissner's corpuscles and Pacinian corpuscles. It outlines the somatosensory pathways including the posterior column-medial lemniscal pathway and spinothalamic pathway.
This document discusses the senses of smell (olfaction) and taste. It notes that smell and taste have a cooperative relationship, with odor contributing approximately 80% of what we perceive as flavor. The main points covered include:
- Smell and taste are classified as special senses along with sight, hearing, and balance
- The olfactory system includes receptors in the nose, olfactory bulbs, and pathways to the brain regions involved in emotion and behavior
- Pheromones influence behaviors through a vomeronasal system present in many animals
- Humans have a less developed sense of smell compared to most animals
- The olfactory epithelium regenerates sensory neurons throughout life but this capacity declines with age
The document summarizes the neural and chemical regulation of respiration. It describes the key respiratory centers in the medulla and pons that control breathing. These include the dorsal and ventral respiratory groups in the medulla and the apneustic and pneumotaxic centers in the pons. Peripheral chemoreceptors in the carotid body and aortic body and central chemoreceptors in the medulla detect changes in blood gases like CO2 and pH to modulate breathing. Increased CO2 and H+ stimulate these chemoreceptors to enhance the activity of the respiratory centers and increase ventilation.
Somatic mechanoceptive sensation.hussein f. sakrHussein Sakr
This document defines and describes different types of sensation, including somatic, visceral, and special sensations. It focuses on somatic sensation, which is initiated by receptors in the skin, muscles, bones and joints. Somatic sensation includes tactile sensations like touch and pressure, thermal sensations, and pain sensation. It discusses the receptors involved and pathways for transmitting different types of somatic sensation, including the dorsal column medial lemniscus system and anterolateral system. Proprioceptive sensation and vibration sense are also defined and their receptors and pathways described.
The somatosensory system allows humans to recognize objects, textures, and social cues through networks of neurons. It produces perceptions of touch, temperature, body position, and pain. Sensory receptors collect information and stimulate neurons to send impulses to the brain. There are different types of sensations including superficial touch and pain, deep proprioception and vibration, and visceral sensations like hunger. The somatosensory system includes exteroceptive senses on the skin, visceroceptive senses in the viscera, and proprioceptive senses in the muscles and joints. Sensory impulses are transmitted through peripheral nerves to the central nervous system to be analyzed and interpreted.
This document summarizes the ascending and descending tracts of the central nervous system. It describes the functional anatomy and regional anatomy of the ascending tracts that transmit sensory information from the periphery to the brain, including the dorsal column-medial lemniscal system and anterolateral system. It also discusses the different classes of sensory receptors, pathways, and relay nuclei involved in transmitting different somatic sensations like touch, proprioception, pain, itch and temperature.
physiology of Sensory nervous system, updated 2021dina merzeban
This document discusses the sensory system. It begins by defining the main components of the sensory system - sensory receptors, sensory pathways, and the somatic sensory cortex. It then goes into detail about the different types of sensory receptors, including their classification, properties, and the sensations they detect. It describes the pathways that sensory signals travel through to reach the brain, including the dorsal column-medial lemniscus pathway and spinothalamic pathway. It concludes by discussing sensory coding and the areas of the cortex involved in processing sensory information.
Cutaneous receptors are classified as exteroreceptors, interoreceptors, and proprioceptors depending on the source of stimulus. Exteroreceptors located in the skin sense touch, temperature, pain and pressure from the external environment. These include mechanoreceptors, thermoreceptors, and nociceptors. Mechanoreceptors like Meissner's corpuscles, Pacinian corpuscles, and Merkel's disks sense different types of touch and vibration. Thermoreceptors detect temperature changes and include free nerve endings and hair follicles. Nociceptors mediate pain through A-delta and C fibers. Signals from cutaneous receptors travel to the somatosensory cortex through the
The document provides an overview of the somatosensory, auditory, olfactory, and gustatory sensory systems. It describes the anatomy and neural pathways of each system from receptor to cortex. Key points include: each system has receptors that convert stimuli into neural signals via hierarchical pathways to the thalamus and sensory cortices; the somatosensory system has touch, pain, and proprioceptive divisions; and the auditory, olfactory, and gustatory systems have tonotopic organization and multiple cortical processing streams. Damage to sensory pathways can result in deficits like deafness, anosmia, or agnosias depending on the lesion location.
This document summarizes the different types of receptors in the human body. It describes exteroceptors, which respond to external stimuli, and interoceptors, which respond to internal stimuli. It provides details on cutaneous receptors for touch, pain, and temperature. It also describes receptors for senses like vision, hearing, and taste. Proprioceptors that detect muscle stretch and position are discussed. The document outlines the classification, functions, and properties of different receptors.
The document discusses the structure and functions of the nervous system. It describes the nervous system as having three main functions: sensory, control, and motor. The central nervous system consists of the brain and spinal cord. Nerves connect the central nervous system to the rest of the body. Sensory nerves carry messages to the CNS and motor nerves carry messages from the CNS to muscles and glands. Reflex actions are involuntary responses that occur through a reflex arc involving sensory neurons, interneurons, and motor neurons. Different regions of the brain control various functions like conscious thought, movement, and balance.
The document summarizes the key differences between the somatic and autonomic nervous systems. The somatic nervous system includes sensory and motor neurons that allow for voluntary movement and conscious perception of senses. The autonomic nervous system unconsciously regulates internal organs and glands and has sympathetic ("fight or flight") and parasympathetic ("rest and digest") divisions. It also reviews the different sensory systems like vision, hearing, smell, taste and touch, and the receptors and pathways involved.
This document discusses the human sensory systems. It describes four types of sensations - superficial, deep, visceral, and special. It then provides details on the receptors, pathways, and neural connections involved in touch, pain, temperature, proprioception, and other senses. Specifically, it outlines the locations and functions of mechanoreceptors like Meissner's corpuscles and Merkel endings, as well as nociceptors that detect pain. It also compares the dorsal column-medial lemniscus pathway and spinothalamic tract, noting their roles in transmitting different sensory signals to the cortex.
This document discusses receptors and neurons that detect sensory information. It begins by defining perception and describing how sensory information is transmitted from receptors to the central nervous system. It then categorizes the different sensory modalities like touch, pain, temperature, and proprioception. The document goes on to describe the different types of sensory receptors, including their locations, the stimuli they detect, and whether they adapt rapidly or slowly. It provides examples of specific receptors like Meissner corpuscles, Pacinian corpuscles, and thermoreceptors. In closing, it notes the uneven distribution of receptors in the skin and modalities detected in the skin.
Touch is the oldest sense and involves mechanoreceptors in the skin that detect deformations. There are four main receptor types - Meissner corpuscles, Pacinian corpuscles, Merkel disks, and Ruffini endings. Tactile information is processed in the peripheral and central nervous systems, with different cortical areas representing information from different body parts. Proprioception provides information about body position and movement through receptors in the muscles and joints. Haptics and proprioception together allow us to identify objects and perceive their location through active touch.
Sensory receptors collect information from the environment and stimulate neurons to send impulses to the brain. There are specialized receptor cells that transform stimuli into electrical signals through transduction. Receptors act as detectors and transducers. The impulses travel along sensory pathways through the dorsal horn, dorsal columns or spinothalamic tract to the thalamus. They then project to the primary somatosensory cortex which has a somatotopic map of the body. The secondary somatosensory cortex integrates information from the primary cortex.
This document discusses myelinated and non-myelinated nerve fibers. It explains that myelinated fibers are covered by a myelin sheath that allows saltatory conduction, moving electrical signals rapidly from node to node. Non-myelinated fibers lack this sheath and conduct signals through simple propagation. The document also covers sensory and motor pathways in the spinal cord and brain, including the roles of upper and lower motor neurons in voluntary muscle movement and spinal reflexes in involuntary movement.
The document discusses the human sensory system. It describes the different types of sensory receptors, including exteroceptors, proprioceptors, and interoceptors. It explains how stimuli are detected by receptors and transmitted as nerve impulses to the central nervous system. Key aspects covered include the transduction of stimuli into electrical signals, classification of nerve fibers, sensory pathways, and the perception and modulation of sensations.
The document discusses the key concepts of sensation and perception, including how the senses of sight, hearing, taste, smell, touch and pain work through processes like transduction and adaptation to convert stimuli into electrical signals that are transmitted to the brain for processing into meaningful perceptions. It covers topics like color vision, sound waves, taste buds, olfactory receptors, touch receptors in the skin, theories of pain perception, and concepts in perception like thresholds and just noticeable differences.
2nd year small group discussion Synapse and sensory receptors.pptxbobehe4189
This document provides information about synapses and sensory receptors presented during a small group discussion at the Rawalpindi Medical University. It begins with introducing the university's motto and learning objectives of the session. It then defines synapses and describes different types of synapses and their structure. It explains synaptic transmission through chemical synapses. It also describes EPSP and IPSP. Finally, it classifies and illustrates different types of sensory receptors, including mechanoreceptors, thermoreceptors, nociceptors, electromagnetic receptors, and chemoreceptors. It provides details about tactile receptors in the skin and deep tissues.
The document discusses several topics related to human senses and perception. It begins by describing the basic processes of sensation, including transduction, adaptation, and the differences between sensations and perceptions. It then provides details on the structure and function of the eye, ear, skin receptors, taste, smell, touch, and pain. Rules of perceptual organization like figure-ground and principles of depth perception are explained. The document also covers illusions and how they demonstrate that perception does not always match objective reality.
This document describes the somatic sensory and motor pathways in the nervous system. It discusses the different types of sensory receptors for touch, pain, temperature, and proprioception. The major somatic sensory pathways are the posterior column pathway for fine touch and proprioception, and the anterolateral pathway for crude touch, pain, and temperature. The spinocerebellar pathway relays proprioceptive information to the cerebellum. Somatic motor commands originate from motor areas of the brain and travel via pathways like the corticospinal tract to lower motor neurons innervating skeletal muscles. The basal ganglia and cerebellum provide feedback to coordinate voluntary muscle contractions.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
Assessment and Planning in Educational technology.pptxKavitha Krishnan
In an education system, it is understood that assessment is only for the students, but on the other hand, the Assessment of teachers is also an important aspect of the education system that ensures teachers are providing high-quality instruction to students. The assessment process can be used to provide feedback and support for professional development, to inform decisions about teacher retention or promotion, or to evaluate teacher effectiveness for accountability purposes.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
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 ...
Main Java[All of the Base Concepts}.docxadhitya5119
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
Executive Directors Chat Leveraging AI for Diversity, Equity, and InclusionTechSoup
Let’s explore the intersection of technology and equity in the final session of our DEI series. Discover how AI tools, like ChatGPT, can be used to support and enhance your nonprofit's DEI initiatives. Participants will gain insights into practical AI applications and get tips for leveraging technology to advance their DEI goals.
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
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria