reticular formation.pptx
•Download as PPTX, PDF•
2 likes•93 views
The reticular formation is a dense network of neurons and fibers located in the core of the brainstem that consists of nuclear masses and long connecting fibers. It receives sensory input from throughout the body and brain and sends output to the thalamus and cortex to regulate states of arousal and consciousness through the reticular activating system. The reticular formation also controls autonomic functions like respiration and heart rate as well as muscle tone and plays a role in attention, learning, and pain modulation through various neurotransmitters.
Report
Share
Report
Share
Recommended
motor cortex
This document summarizes the cortical and brain stem control of motor function. It discusses how the motor cortex, premotor area, and supplementary motor area initiate voluntary movements by activating patterns stored in lower brain areas like the brain stem and cerebellum. These lower centers then send control signals to muscles. It describes areas of the motor cortex and their functions, as well as pathways involving the brain stem, basal ganglia, cerebellum, and spinal cord that integrate to control motor functions. Damage to different areas can impact speech, eye and head movements, and dexterity.
Anatomy and Physiology: Brain Stem
Here is anatomy and physiology of brain stem. Where we will discuss all three parts of brain stem. Starting from medulla, second is pons and third is mid brain. In this video I am presenting anatomy and physiology of medulla. Anatomy of medulla: Medulla Oblongata or more simply medulla is part of brain stem which forms base of the brain stem. Location of medulla oblongata is superior to spinal cord and inferior to Pons. It contains pyramid, olive and above pyramidal structure, there is decussation of pyramids which explains why each part of brain controls opposite part of body. Adding to that medulla also has several nuclei which controls activity of cardiovascular system and respiratory system. Medulla also has nuclei for controlling reflexes of vomiting, swallowing, hiccuping, coughing and sneezing. It has also nuclei for test, hearing and balance. Medulla also contains nuclei of cranial nerve number VIII, IX, X, XI and XII. Functions of medulla or what dose medulla do? So medulla controls blood pressure, diameter of wall of arteries, heart rate, basal respiration rate and also vomiting, swallowing, hiccuping, coughing and sneezing.
In this video, we explain you about anatomy and physiology of Pons. The reference material used to make video is: Principles of Anatomy and Physiology Gerard J. Tortora, Bryan H. Derrickson. Pons is part of brain stem, present superior to medulla, inferior to mid brain and anterior to cerebellum. Pons means a bridge. As the name denotes, it connects other areas of brain. Neurons extending from cerebral cortex to pons makes corticopontine tract. Pons is connected to cerebellum by middle cerebral peduncle. Pons has vestibular nuclei, which is part of equilibrium pathways from inner ear to brain. Pons has also respiratory nuclei. Along with rhythmicity area of medulla, pons controls basal respiratory rhythm. Pons also contains nuclei for cranial nerve number V, VI,VII, and VIII.
Physiology of thalamus
The document provides information about the physiology of the thalamus. It discusses the location and classification of thalamic nuclei, as well as their afferent and efferent connections and functions. It also describes two clinical cases. The first case is of a 60-year old man who suffered a stroke and subsequently had loss of sensation on one side of his body along with abnormal pain responses on examination. Imaging revealed a hemorrhage in the left thalamus. The diagnosis is a thalamic syndrome resulting from rewiring of damaged touch pathways in the thalamus to process pain instead, causing allodynia or hyperalgesia.
Cerebral cortex ppt
The cerebral cortex is a thin sheet of neural tissue that surrounds the cerebrum. It plays a key role in functions like memory, awareness, language, and consciousness. It is divided into two hemispheres and four lobes. It has six layers and is made up of grey matter on the inside and white matter on the outside. The cortex contains several functional areas including sensory, motor, and associated areas. The sensory areas process somatosensation, vision, hearing, smell, and taste. The motor areas control voluntary movement. The associated areas integrate information for functions like cognition and language.
Thalamus ppt
The thalamus is a structure located in the middle of the brain between the cerebral cortex and midbrain. It is the largest component of the diencephalon. The thalamus acts as a relay station for sensory information (except smell) sending signals to the appropriate areas of the cerebral cortex. It is divided into nuclei that each have distinct functions and connections related to motor control, sensory processing and integration, arousal, memory and cognition. Damage to different thalamic nuclei can disrupt various functions and result in sensory deficits, movement problems or changes to consciousness.
Cerebellum ppt
The document provides an overview of the cerebellum including its:
- Physiological anatomy, divisions, and histological structure
- Neural circuits and neuronal activity
- Connections with other parts of the brain and spinal cord
- Key functions in controlling posture, balance, muscle tone, and voluntary movement
- Effects of cerebellar lesions and clinical tests used to assess cerebellar dysfunction
Midbrain
The midbrain connects the hindbrain and forebrain. It is involved in vision, hearing, motor control and other functions. The midbrain contains several structures including the tectum, tegmentum, cerebral peduncles, cerebral aqueduct, superior and inferior colliculi, substantia nigra and red nucleus. It also contains nuclei associated with cranial nerves III, IV, V and VI. Sensory and motor tracts pass through the midbrain connecting different parts of the brain and spinal cord.
The cerebellum
The cerebellum is located in the posterior cranial fossa. It has three lobes - the anterior, posterior and flocculonodular lobes. It receives inputs from various parts of the brain and spinal cord via afferent pathways and sends outputs to motor areas of the brain via efferent pathways. The cerebellum plays key roles in motor control such as regulation of muscle tone and coordination of skilled voluntary movements, control of equilibrium and learning of new motor skills. Dysfunction of the cerebellum results in disturbances of posture, ataxia and intention tremors which can be assessed using clinical tests.
Recommended
motor cortex
This document summarizes the cortical and brain stem control of motor function. It discusses how the motor cortex, premotor area, and supplementary motor area initiate voluntary movements by activating patterns stored in lower brain areas like the brain stem and cerebellum. These lower centers then send control signals to muscles. It describes areas of the motor cortex and their functions, as well as pathways involving the brain stem, basal ganglia, cerebellum, and spinal cord that integrate to control motor functions. Damage to different areas can impact speech, eye and head movements, and dexterity.
Anatomy and Physiology: Brain Stem
Here is anatomy and physiology of brain stem. Where we will discuss all three parts of brain stem. Starting from medulla, second is pons and third is mid brain. In this video I am presenting anatomy and physiology of medulla. Anatomy of medulla: Medulla Oblongata or more simply medulla is part of brain stem which forms base of the brain stem. Location of medulla oblongata is superior to spinal cord and inferior to Pons. It contains pyramid, olive and above pyramidal structure, there is decussation of pyramids which explains why each part of brain controls opposite part of body. Adding to that medulla also has several nuclei which controls activity of cardiovascular system and respiratory system. Medulla also has nuclei for controlling reflexes of vomiting, swallowing, hiccuping, coughing and sneezing. It has also nuclei for test, hearing and balance. Medulla also contains nuclei of cranial nerve number VIII, IX, X, XI and XII. Functions of medulla or what dose medulla do? So medulla controls blood pressure, diameter of wall of arteries, heart rate, basal respiration rate and also vomiting, swallowing, hiccuping, coughing and sneezing.
In this video, we explain you about anatomy and physiology of Pons. The reference material used to make video is: Principles of Anatomy and Physiology Gerard J. Tortora, Bryan H. Derrickson. Pons is part of brain stem, present superior to medulla, inferior to mid brain and anterior to cerebellum. Pons means a bridge. As the name denotes, it connects other areas of brain. Neurons extending from cerebral cortex to pons makes corticopontine tract. Pons is connected to cerebellum by middle cerebral peduncle. Pons has vestibular nuclei, which is part of equilibrium pathways from inner ear to brain. Pons has also respiratory nuclei. Along with rhythmicity area of medulla, pons controls basal respiratory rhythm. Pons also contains nuclei for cranial nerve number V, VI,VII, and VIII.
Physiology of thalamus
The document provides information about the physiology of the thalamus. It discusses the location and classification of thalamic nuclei, as well as their afferent and efferent connections and functions. It also describes two clinical cases. The first case is of a 60-year old man who suffered a stroke and subsequently had loss of sensation on one side of his body along with abnormal pain responses on examination. Imaging revealed a hemorrhage in the left thalamus. The diagnosis is a thalamic syndrome resulting from rewiring of damaged touch pathways in the thalamus to process pain instead, causing allodynia or hyperalgesia.
Cerebral cortex ppt
The cerebral cortex is a thin sheet of neural tissue that surrounds the cerebrum. It plays a key role in functions like memory, awareness, language, and consciousness. It is divided into two hemispheres and four lobes. It has six layers and is made up of grey matter on the inside and white matter on the outside. The cortex contains several functional areas including sensory, motor, and associated areas. The sensory areas process somatosensation, vision, hearing, smell, and taste. The motor areas control voluntary movement. The associated areas integrate information for functions like cognition and language.
Thalamus ppt
The thalamus is a structure located in the middle of the brain between the cerebral cortex and midbrain. It is the largest component of the diencephalon. The thalamus acts as a relay station for sensory information (except smell) sending signals to the appropriate areas of the cerebral cortex. It is divided into nuclei that each have distinct functions and connections related to motor control, sensory processing and integration, arousal, memory and cognition. Damage to different thalamic nuclei can disrupt various functions and result in sensory deficits, movement problems or changes to consciousness.
Cerebellum ppt
The document provides an overview of the cerebellum including its:
- Physiological anatomy, divisions, and histological structure
- Neural circuits and neuronal activity
- Connections with other parts of the brain and spinal cord
- Key functions in controlling posture, balance, muscle tone, and voluntary movement
- Effects of cerebellar lesions and clinical tests used to assess cerebellar dysfunction
Midbrain
The midbrain connects the hindbrain and forebrain. It is involved in vision, hearing, motor control and other functions. The midbrain contains several structures including the tectum, tegmentum, cerebral peduncles, cerebral aqueduct, superior and inferior colliculi, substantia nigra and red nucleus. It also contains nuclei associated with cranial nerves III, IV, V and VI. Sensory and motor tracts pass through the midbrain connecting different parts of the brain and spinal cord.
The cerebellum
The cerebellum is located in the posterior cranial fossa. It has three lobes - the anterior, posterior and flocculonodular lobes. It receives inputs from various parts of the brain and spinal cord via afferent pathways and sends outputs to motor areas of the brain via efferent pathways. The cerebellum plays key roles in motor control such as regulation of muscle tone and coordination of skilled voluntary movements, control of equilibrium and learning of new motor skills. Dysfunction of the cerebellum results in disturbances of posture, ataxia and intention tremors which can be assessed using clinical tests.
Thalamus final
The thalamus is a large egg-shaped structure located in the brain that serves as a relay center for sensory and motor signals to and from the cerebral cortex. It has multiple nuclei that receive input from various sensory systems and project to different regions of the cortex. The thalamus plays an important role in sensory perception and motor control through its connections with the cortex, cerebellum, and basal ganglia.
Anatomy of ascending and descending tracts
This document discusses the ascending tracts of the spinal cord, which transmit sensory information from the body to the brain. It describes the three neuron chain that makes up the ascending sensory pathway and the different tracts including the lateral spinothalamic tract for pain/temperature, anterior spinothalamic tract for touch/pressure, and fasciculus gracilis and cuneatus for proprioception. It outlines the pathways each tract takes from spinal cord to thalamus to cortex, as well as clinical implications of damage to different tracts such as loss of sensation on one side of the body.
Reticular formation
1). The reticular formation is an ill-defined region in the brainstem comprising neurons and fibers that extends from the spinal cord to the thalamus. It is involved in arousal, attention, sleep-wake cycles, and autonomic functions.
2). The ascending reticular activating system projects from the brainstem reticular formation to the thalamus and cortex, promoting wakefulness. The descending pathway projects to the spinal cord and is involved in motor function.
3). The reticular formation receives inputs from sensory systems and projects to the thalamus, hypothalamus, and spinal cord. It regulates functions like muscle tone, respiration, cardiovascular control, and endocrine secretion.
Reticularformation
The reticular formation is a network of neurons located in the brainstem that serves several important functions. It is involved in regulating states of consciousness like sleep and wakefulness via the ascending reticular activating system. The reticular formation also controls posture and balance through reticulospinal tracts that project to motor neurons in the spinal cord. It is comprised of several nuclei that contain different neurotransmitters and integrate sensory information from various modalities to coordinate motor functions. Lesions in specific areas of the reticular formation can impact muscle tone and result in conditions like decorticate posturing.
motor areas of cerebral cortex
motor areas of cerebral cortex with reference to their lesion disorders . and some of the tracts connecting them to the motor nerves nuclei in the spinal cord and cranial nerves
Thalamus
The thalamus is divided into three parts: the epithalamus, dorsal thalamus, and ventral thalamus. The dorsal thalamus contains four types of nuclei: specific sensory relay nuclei, nuclei concerned with efferent control, nonspecific projection nuclei, and nuclei concerned with higher functions. The ventral thalamus contains the reticular nucleus. The thalamus acts as a relay center for sensory information and plays roles in motor control, arousal, consciousness, memory, and emotions. Damage to the thalamus can result in sensory deficits and symptoms like loss of sensation and memory.
ASCENDING TRACTS
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.
Cerebellum
The document provides information about the cerebellum, including its functional divisions, histology, input and output pathways, and connections. It discusses how the cerebellum is divided into the cerebrocerebellum, vestibulocerebellum, and spinocerebellum based on their connections. It also describes the layers of the cerebellar cortex including the molecular layer, Purkinje cell layer, and granular layer. The input pathways to the cerebellum are the corticopontocerebellar pathway, olivocerebellar tract, vestibulocerebellar fibers, and reticulocerebellar fibers. The output of the cerebellum projects to all descending pathways
Ascending tract of the Spinal cord
an overview of the ascending tract of the spinal cord....an anatomical approach to understand the somato-sensory pathway.
Prepared as a class presentation .
Diencephalon
The diencephalon is the area surrounding the third ventricle of the brain. It contains several parts including the thalamus, hypothalamus, epithalamus, and subthalamus. The thalamus relays sensory information to the cortex and is involved in visual and auditory processing. The hypothalamus regulates autonomic functions and homeostasis through connections to the pituitary gland and autonomic nervous system. Lesions in the diencephalon can disrupt temperature regulation, appetite, water balance, and other homeostatic processes.
Thalamus
The thalamus is a paired, oval structure located in the diencephalon that serves as a relay center for sensory and motor signals to and from the cerebral cortex. It is divided into several nuclei that process different sensory modalities. The thalamus receives input from various areas and projects to specific regions of the cortex. Damage to certain thalamic nuclei can disrupt motor control, sensory processing, and cause syndromes like thalamic pain. Surgical procedures targeting thalamic nuclei have been used to treat chronic pain conditions.
Cns 14
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.
Anatomy of brainstem
The brainstem is located between the cerebrum and spinal cord. It consists of the midbrain, pons, and medulla oblongata. The midbrain connects the pons and cerebrum and contains the superior and inferior colliculi. The pons connects to the cerebellum via peduncles and contains pontine nuclei and cranial nerve nuclei. The medulla oblongata connects to the spinal cord and contains cranial nerve nuclei, the inferior olives, and tracts such as the gracile and cuneate fasciculi.
Anatomy of midbrain
The brain stem is located between the cerebrum and spinal cord, and consists of the midbrain, pons, and medulla oblongata. The midbrain connects the forebrain to the pons and cerebellum. It contains important centers for visual and auditory reflexes, and gives rise to the trochlear nerve. Key structures in the midbrain include the superior and inferior colliculi, oculomotor nucleus, red nucleus, and substantia nigra. The midbrain serves to relay motor and sensory signals between the spinal cord and forebrain.
Review of neurophysiology (sensory system) 2016
This document provides an overview of neurophysiology and the nervous system. It discusses the following key points in 3 sentences or less:
The central nervous system is made up of the brain and spinal cord. The brain controls all body functions and is divided into areas that control thinking, memory, movement, and other tasks. The peripheral nervous system connects the central nervous system to the rest of the body and is made up of nerves and sensory organs.
Neuroanatomy of brain stem
The document summarizes the neuroanatomy of the brain stem. It describes the three parts of the brain stem - medulla oblongata, pons, and midbrain. The medulla contains vital centers that regulate functions like respiration and heart rate. It also contains the nuclei of several cranial nerves. The pons connects parts of the brain and contains nuclei of cranial nerves involved in functions like eye movement and facial expression. The midbrain contains reflex centers for vision and hearing and pathways connecting the brain and spinal cord.
reticular formation and limbic system
The document summarizes key aspects of the brainstem and its functions. It discusses three regions of the brainstem - medulla oblongata, pons, and midbrain. Each region contains cranial nerves and nuclei that control autonomic functions. The reticular formation is a network of neurons running through the core of the brainstem that is involved in arousal, alertness, sleep, and motor control. Sensory information is received by the reticular formation and it projects both upwards and downwards. The brainstem modulates consciousness, sensory and motor functions, and plays an important role in emotion, memory, and learning.
NEUROANATOMY OF BRAINSTEM
BRAINSTEM
The Brainstem lies at the base of the brain and the top of the spinal cord.
The brainstem is located in the posterior cranial fossa.
The brainstem is the structure that connects the cerebrum of the brain to the spinal cord and cerebellum.
Provides a pathway for tracts running between higher and lower neural centers.
Divided into 3 major divisions:
midbrain,
pons, and
medulla oblongata.
It is responsible for many vital functions of life, such as breathing, consciousness, blood pressure, heart rate, and sleep.
It contains many critical collections of white and grey matter.
The grey matter within the brainstem consists of nerve cell bodies and form many important brainstem nuclei. Ten of the twelve cranial nerves arise from their cranial nerve nuclei in the brainstem.
The white matter tracts of the brainstem include axons of nerves traversing their course to different structures. These tracts travel both to the brain (afferent) and from the brain (efferent) such as the somatosensory pathways and the corticospinal tracts, respectively.
Mid Brain
The midbrain is continuous with the cerebral hemisphere.
The upper posterior (i.e. rear) portion of the midbrain is called the tectum, which means "roof."
The surface of the tectum is covered with four bumps representing two paired structures: the superior and inferior colliculi.
The superior colliculi are involved in eye movements and visual processing, while the inferior colliculi are involved in auditory processing.
Another important nucleus, the substantia nigra, is located here.
The substantia nigra is rich in dopamine neurons and is considered part of the basal ganglia.
Pons
An important pathway for tracts that run from the cerebrum down to the medulla and spinal cord, as well as for tracts that travel up into the brain.
It also forms important connections with the cerebellum via fibre bundles known as the cerebellar peduncles.
Posteriorly, the pons and medulla are separated from the cerebellum by the fourth ventricle.
Home to several nuclei for cranial nerves.
Medulla
The point where the brainstem connects to the spinal cord.
Contains a nucleus called the nucleus of the solitary tract that is crucial for our survival (receives information about blood flow, along with information about levels of oxygen and carbon dioxide in the blood, from the heart and major blood vessels).
When this information suggests a discordance with bodily needs (e.g. blood pressure is too low), there are reflexive actions initiated in the nucleus of the solitary tract to bring things back to within the desired range.
Blood Supply
The brain stem receives its blood supply exclusively from the posterior circulation, including the vertebrae and basilar artery.
The medulla receives its blood supply from the vertebral via medial and lateral perforating arteries.
The pons and midbrain receive their blood from the basilar via the medial and lateral perforating arteries.
Basal ganglia
The document provides an overview of the basal ganglia. It discusses the physiological anatomy and components of the basal ganglia, including the caudate nucleus, putamen, globus pallidus, substantia nigra, and subthalamic nucleus. It describes the connections and functional neuronal circuits of the basal ganglia. The functions of the basal ganglia in motor control and disorders such as Parkinson's disease, chorea, athetosis, and Huntington's disease are summarized.
Thalamus
The thalamus is a paired symmetrical structure located in the center of the brain that relays sensory and motor signals between the brainstem and cerebral cortex. It is divided into several nuclei that have distinct connections and functions. The document provides detailed information on the anatomy, physiology, functional organization and clinical syndromes associated with lesions of different thalamic nuclei. Key points include a description of the gross anatomy and location of the thalamus, its blood supply, the nuclei and their connections, and syndromes associated with infarcts in the posterolateral and medial thalamic territories.
13. The Nervous System
The document summarizes key aspects of the nervous system, including:
1) It describes the basic structures and functions of neurons, neuroglia, the cerebrum, cerebellum, diencephalon, and brain stem.
2) It explains the organization and direction of signals in the central and peripheral nervous systems, including afferent, efferent, somatic, and autonomic nerves.
3) It outlines the processes of neuronal signaling including resting potential, depolarization, repolarization, synaptic transmission, and types of neurotransmitters.
4) It defines structures like the meninges and cerebrospinal fluid, and reflexes like stretch, withdrawal, and crossed extensor
Reticular activating system
The reticular formation is a network of neurons located in the brainstem that performs several important functions. It receives sensory information from the spinal cord and senses arousal levels. The reticular formation contains nuclei that are involved in motor control, sleep-wake cycles, autonomic functions, and modulating pain. It has ascending and descending pathways that connect to the thalamus and cerebral cortex and help regulate states of consciousness like sleep and wakefulness.
More Related Content
What's hot
Thalamus final
The thalamus is a large egg-shaped structure located in the brain that serves as a relay center for sensory and motor signals to and from the cerebral cortex. It has multiple nuclei that receive input from various sensory systems and project to different regions of the cortex. The thalamus plays an important role in sensory perception and motor control through its connections with the cortex, cerebellum, and basal ganglia.
Anatomy of ascending and descending tracts
This document discusses the ascending tracts of the spinal cord, which transmit sensory information from the body to the brain. It describes the three neuron chain that makes up the ascending sensory pathway and the different tracts including the lateral spinothalamic tract for pain/temperature, anterior spinothalamic tract for touch/pressure, and fasciculus gracilis and cuneatus for proprioception. It outlines the pathways each tract takes from spinal cord to thalamus to cortex, as well as clinical implications of damage to different tracts such as loss of sensation on one side of the body.
Reticular formation
1). The reticular formation is an ill-defined region in the brainstem comprising neurons and fibers that extends from the spinal cord to the thalamus. It is involved in arousal, attention, sleep-wake cycles, and autonomic functions.
2). The ascending reticular activating system projects from the brainstem reticular formation to the thalamus and cortex, promoting wakefulness. The descending pathway projects to the spinal cord and is involved in motor function.
3). The reticular formation receives inputs from sensory systems and projects to the thalamus, hypothalamus, and spinal cord. It regulates functions like muscle tone, respiration, cardiovascular control, and endocrine secretion.
Reticularformation
The reticular formation is a network of neurons located in the brainstem that serves several important functions. It is involved in regulating states of consciousness like sleep and wakefulness via the ascending reticular activating system. The reticular formation also controls posture and balance through reticulospinal tracts that project to motor neurons in the spinal cord. It is comprised of several nuclei that contain different neurotransmitters and integrate sensory information from various modalities to coordinate motor functions. Lesions in specific areas of the reticular formation can impact muscle tone and result in conditions like decorticate posturing.
motor areas of cerebral cortex
motor areas of cerebral cortex with reference to their lesion disorders . and some of the tracts connecting them to the motor nerves nuclei in the spinal cord and cranial nerves
Thalamus
The thalamus is divided into three parts: the epithalamus, dorsal thalamus, and ventral thalamus. The dorsal thalamus contains four types of nuclei: specific sensory relay nuclei, nuclei concerned with efferent control, nonspecific projection nuclei, and nuclei concerned with higher functions. The ventral thalamus contains the reticular nucleus. The thalamus acts as a relay center for sensory information and plays roles in motor control, arousal, consciousness, memory, and emotions. Damage to the thalamus can result in sensory deficits and symptoms like loss of sensation and memory.
ASCENDING TRACTS
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.
Cerebellum
The document provides information about the cerebellum, including its functional divisions, histology, input and output pathways, and connections. It discusses how the cerebellum is divided into the cerebrocerebellum, vestibulocerebellum, and spinocerebellum based on their connections. It also describes the layers of the cerebellar cortex including the molecular layer, Purkinje cell layer, and granular layer. The input pathways to the cerebellum are the corticopontocerebellar pathway, olivocerebellar tract, vestibulocerebellar fibers, and reticulocerebellar fibers. The output of the cerebellum projects to all descending pathways
Ascending tract of the Spinal cord
an overview of the ascending tract of the spinal cord....an anatomical approach to understand the somato-sensory pathway.
Prepared as a class presentation .
Diencephalon
The diencephalon is the area surrounding the third ventricle of the brain. It contains several parts including the thalamus, hypothalamus, epithalamus, and subthalamus. The thalamus relays sensory information to the cortex and is involved in visual and auditory processing. The hypothalamus regulates autonomic functions and homeostasis through connections to the pituitary gland and autonomic nervous system. Lesions in the diencephalon can disrupt temperature regulation, appetite, water balance, and other homeostatic processes.
Thalamus
The thalamus is a paired, oval structure located in the diencephalon that serves as a relay center for sensory and motor signals to and from the cerebral cortex. It is divided into several nuclei that process different sensory modalities. The thalamus receives input from various areas and projects to specific regions of the cortex. Damage to certain thalamic nuclei can disrupt motor control, sensory processing, and cause syndromes like thalamic pain. Surgical procedures targeting thalamic nuclei have been used to treat chronic pain conditions.
Cns 14
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.
Anatomy of brainstem
The brainstem is located between the cerebrum and spinal cord. It consists of the midbrain, pons, and medulla oblongata. The midbrain connects the pons and cerebrum and contains the superior and inferior colliculi. The pons connects to the cerebellum via peduncles and contains pontine nuclei and cranial nerve nuclei. The medulla oblongata connects to the spinal cord and contains cranial nerve nuclei, the inferior olives, and tracts such as the gracile and cuneate fasciculi.
Anatomy of midbrain
The brain stem is located between the cerebrum and spinal cord, and consists of the midbrain, pons, and medulla oblongata. The midbrain connects the forebrain to the pons and cerebellum. It contains important centers for visual and auditory reflexes, and gives rise to the trochlear nerve. Key structures in the midbrain include the superior and inferior colliculi, oculomotor nucleus, red nucleus, and substantia nigra. The midbrain serves to relay motor and sensory signals between the spinal cord and forebrain.
Review of neurophysiology (sensory system) 2016
This document provides an overview of neurophysiology and the nervous system. It discusses the following key points in 3 sentences or less:
The central nervous system is made up of the brain and spinal cord. The brain controls all body functions and is divided into areas that control thinking, memory, movement, and other tasks. The peripheral nervous system connects the central nervous system to the rest of the body and is made up of nerves and sensory organs.
Neuroanatomy of brain stem
The document summarizes the neuroanatomy of the brain stem. It describes the three parts of the brain stem - medulla oblongata, pons, and midbrain. The medulla contains vital centers that regulate functions like respiration and heart rate. It also contains the nuclei of several cranial nerves. The pons connects parts of the brain and contains nuclei of cranial nerves involved in functions like eye movement and facial expression. The midbrain contains reflex centers for vision and hearing and pathways connecting the brain and spinal cord.
reticular formation and limbic system
The document summarizes key aspects of the brainstem and its functions. It discusses three regions of the brainstem - medulla oblongata, pons, and midbrain. Each region contains cranial nerves and nuclei that control autonomic functions. The reticular formation is a network of neurons running through the core of the brainstem that is involved in arousal, alertness, sleep, and motor control. Sensory information is received by the reticular formation and it projects both upwards and downwards. The brainstem modulates consciousness, sensory and motor functions, and plays an important role in emotion, memory, and learning.
NEUROANATOMY OF BRAINSTEM
BRAINSTEM
The Brainstem lies at the base of the brain and the top of the spinal cord.
The brainstem is located in the posterior cranial fossa.
The brainstem is the structure that connects the cerebrum of the brain to the spinal cord and cerebellum.
Provides a pathway for tracts running between higher and lower neural centers.
Divided into 3 major divisions:
midbrain,
pons, and
medulla oblongata.
It is responsible for many vital functions of life, such as breathing, consciousness, blood pressure, heart rate, and sleep.
It contains many critical collections of white and grey matter.
The grey matter within the brainstem consists of nerve cell bodies and form many important brainstem nuclei. Ten of the twelve cranial nerves arise from their cranial nerve nuclei in the brainstem.
The white matter tracts of the brainstem include axons of nerves traversing their course to different structures. These tracts travel both to the brain (afferent) and from the brain (efferent) such as the somatosensory pathways and the corticospinal tracts, respectively.
Mid Brain
The midbrain is continuous with the cerebral hemisphere.
The upper posterior (i.e. rear) portion of the midbrain is called the tectum, which means "roof."
The surface of the tectum is covered with four bumps representing two paired structures: the superior and inferior colliculi.
The superior colliculi are involved in eye movements and visual processing, while the inferior colliculi are involved in auditory processing.
Another important nucleus, the substantia nigra, is located here.
The substantia nigra is rich in dopamine neurons and is considered part of the basal ganglia.
Pons
An important pathway for tracts that run from the cerebrum down to the medulla and spinal cord, as well as for tracts that travel up into the brain.
It also forms important connections with the cerebellum via fibre bundles known as the cerebellar peduncles.
Posteriorly, the pons and medulla are separated from the cerebellum by the fourth ventricle.
Home to several nuclei for cranial nerves.
Medulla
The point where the brainstem connects to the spinal cord.
Contains a nucleus called the nucleus of the solitary tract that is crucial for our survival (receives information about blood flow, along with information about levels of oxygen and carbon dioxide in the blood, from the heart and major blood vessels).
When this information suggests a discordance with bodily needs (e.g. blood pressure is too low), there are reflexive actions initiated in the nucleus of the solitary tract to bring things back to within the desired range.
Blood Supply
The brain stem receives its blood supply exclusively from the posterior circulation, including the vertebrae and basilar artery.
The medulla receives its blood supply from the vertebral via medial and lateral perforating arteries.
The pons and midbrain receive their blood from the basilar via the medial and lateral perforating arteries.
Basal ganglia
The document provides an overview of the basal ganglia. It discusses the physiological anatomy and components of the basal ganglia, including the caudate nucleus, putamen, globus pallidus, substantia nigra, and subthalamic nucleus. It describes the connections and functional neuronal circuits of the basal ganglia. The functions of the basal ganglia in motor control and disorders such as Parkinson's disease, chorea, athetosis, and Huntington's disease are summarized.
Thalamus
The thalamus is a paired symmetrical structure located in the center of the brain that relays sensory and motor signals between the brainstem and cerebral cortex. It is divided into several nuclei that have distinct connections and functions. The document provides detailed information on the anatomy, physiology, functional organization and clinical syndromes associated with lesions of different thalamic nuclei. Key points include a description of the gross anatomy and location of the thalamus, its blood supply, the nuclei and their connections, and syndromes associated with infarcts in the posterolateral and medial thalamic territories.
What's hot (20)
Similar to reticular formation.pptx
13. The Nervous System
The document summarizes key aspects of the nervous system, including:
1) It describes the basic structures and functions of neurons, neuroglia, the cerebrum, cerebellum, diencephalon, and brain stem.
2) It explains the organization and direction of signals in the central and peripheral nervous systems, including afferent, efferent, somatic, and autonomic nerves.
3) It outlines the processes of neuronal signaling including resting potential, depolarization, repolarization, synaptic transmission, and types of neurotransmitters.
4) It defines structures like the meninges and cerebrospinal fluid, and reflexes like stretch, withdrawal, and crossed extensor
Reticular activating system
The reticular formation is a network of neurons located in the brainstem that performs several important functions. It receives sensory information from the spinal cord and senses arousal levels. The reticular formation contains nuclei that are involved in motor control, sleep-wake cycles, autonomic functions, and modulating pain. It has ascending and descending pathways that connect to the thalamus and cerebral cortex and help regulate states of consciousness like sleep and wakefulness.
Reticular formation.pptx
The reticular formation is a diffuse mass of neurons and fibers in the brainstem that regulates vital functions like consciousness, respiration, blood pressure, and muscle tone. It receives inputs from sensory systems and connects to all levels of the central nervous system. The reticular formation contains nuclei that can be divided into median, medial, and lateral columns based on neuron size. These nuclei have ascending and descending connections and are involved in arousal, sensory modulation, and motor control. The reticular formation plays an important role in regulating consciousness, autonomic functions, and motor activity through its widespread connections throughout the brain and spinal cord.
Chapter 2 Ppp
The document summarizes key aspects of neuroscience and the nervous system in 3 paragraphs:
1) It describes the main types of neurons - sensory neurons, motor neurons, and interneurons - and their functions of receiving input, output to muscles/glands, and carrying information between neurons.
2) It outlines the basic parts and functions of individual neurons, including dendrites, cell body, axon, myelin sheath, and how they communicate via action potentials and neurotransmitters at synapses.
3) It provides a high-level overview of the main parts and divisions of the nervous system, including the central nervous system (brain and spinal cord), peripheral nervous system, and sympathetic and parasympathetic
Chapter 2 Lecture Disco 4e
The document discusses the structure and function of neurons and the nervous system in 3 paragraphs:
1) It describes the basic parts of a neuron including the cell body, dendrites, axon, and myelin sheath. It explains how neurons communicate via action potentials and neurotransmitters at synapses.
2) It provides an overview of the central nervous system (brain and spinal cord) and peripheral nervous system. It also mentions the sympathetic and parasympathetic nervous systems.
3) It briefly introduces several areas of the brain including the hindbrain, midbrain, forebrain, and cortex. It notes some of the functions of the cerebellum, medulla, and thalamus.
Review Of Anatomy And Physiology Of The Nervous
The document reviews the anatomy and physiology of the nervous system. It describes the central nervous system (brain and spinal cord) and peripheral nervous system. It discusses the structure and function of neurons, classification of neurons, and the components and roles of the nervous system including the brain, spinal cord, cranial nerves and vascular supply. It provides an overview of the organization, tissues and pathways involved in the nervous system.
Nerve (1).PPT
The nervous system is composed of the central nervous system (brain and spinal cord) and peripheral nervous system. The central nervous system contains the brain, which has three main areas - the cerebrum, cerebellum, and brainstem. The peripheral nervous system contains nerves that connect the central nervous system to the rest of the body and is divided into the somatic and autonomic nervous systems. Neurons are the basic functional units of the nervous system and communicate via electrical and chemical signals across synapses to coordinate sensation, thought, and movement.
Presentation 16 - Nervous System
The nervous system is composed of neurons and glial cells. Neurons transmit signals through electrical impulses called action potentials. Communication between neurons occurs at synapses through neurotransmitters. The vertebrate nervous system includes the central nervous system, which processes information, and the peripheral nervous system, which connects to sensory organs and muscles. The brain contains specialized regions that control functions like movement, senses, emotions, and consciousness.
Central nervous-system-09-10
The document summarizes the functional organization and anatomy of the central nervous system (CNS). It describes how the CNS is organized hierarchically from the spinal cord up to the cerebral cortex. It also discusses the lateralized organization of the left and right hemispheres and localized organization of different brain functions. Key components of the CNS discussed include the spinal cord, brainstem, cerebellum, hypothalamus, thalamus, basal ganglia, limbic system, and cerebral cortex. The document also provides an overview of reflex arcs and their significance in assessing CNS function.
neuron & nervous system -fernando- biodeluna
The document discusses the nervous system, including the central nervous system which contains the brain and spinal cord, and the peripheral nervous system which contains all peripheral nerves. It describes the basic functional unit of the nervous system as the neuron, which sends impulses to and from the central and peripheral nervous systems and effectors like muscles and glands. Key parts of the neuron are described as the dendrites, cell body, nucleus, axon, myelin sheath, and nodes of Ranvier.
Physbrain
This document provides an outline for a lecture on neurophysiology. It begins with an introduction and overview of the nervous system, including its basic functions of sensory, interpretive, and motor functions. It then discusses the fine anatomy of the nervous system including neurons, the central nervous system, peripheral nervous system, and divisions of the peripheral nervous system. Finally, it covers topics like the structure and function of neurons, neuroglia, myelination, regeneration, and action potentials.
Brain Anatomy & Physiology
The document provides an overview of the nervous system, including its basic functions and organization. It describes the different types of neurons (sensory, motor, interneurons), divisions of the nervous system (central, peripheral, somatic, autonomic), and components of neurons (cell body, dendrites, axon, myelin sheath). It also summarizes the mechanisms of the action potential, synaptic transmission, and refractory periods.
Human regulatory system 1
The regulatory system in the human body consists of the neural system, endocrine system, and sensory organs. The neural system contains nerve cells that transmit electrical and chemical signals throughout the body to coordinate functions. Disorders can occur if there are imbalances in neurotransmitters in the neural system, which can be caused by conditions like Parkinson's disease or affected by drugs that influence neurotransmitters.
Nerve
The nervous system is composed of the central nervous system (brain and spinal cord) and the peripheral nervous system. The central nervous system contains neurons and neural pathways that process and integrate sensory information and coordinate voluntary and involuntary motor responses. The peripheral nervous system comprises the nerves and ganglia outside of the brain and spinal cord. It contains the somatic and autonomic divisions. Neurons are the basic functional units of the nervous system, consisting of a cell body, dendrites, and axon. They transmit electrochemical signals via synapses to coordinate sensory perception and motor responses.
Nerve PPT BPHARM 1ST YEAR HUMAN ANATOMY PHYSIOLOGY.PPT
The nervous system is composed of the central nervous system (brain and spinal cord) and peripheral nervous system. The central nervous system contains gray matter containing neuron cell bodies and white matter containing axon tracts. The peripheral nervous system contains 31 pairs of spinal nerves and 12 pairs of cranial nerves. The brain is divided into the cerebrum, cerebellum, and brainstem. The cerebrum contains the cerebral cortex and diencephalon. Neurons communicate via synapses and generate action potentials through ion channel openings. The autonomic nervous system regulates involuntary functions through the sympathetic and parasympathetic divisions.
Nervous tissue 1
Lecture notes and diagrams to help high school anatomy and physiology students learn the general functions of the nervous system and types of glial support nerve cells, types of neurons and anatomy of typical neurons.
The nervous system
Functions the Nervous System
Sensory Functions- Helps the body respond to stimuli.
Integrative Functions- Interprets responses to stimuli in the body.
Motor Functions- Coordinates responses to stimuli in the body.
Neurons
2. Physiology of the Nervous Sys Homeostasis.pptx
The document provides an overview of the physiology of the nervous system. It discusses the cellular components, organization, and divisions of the nervous system including the central nervous system and peripheral nervous system. Key topics covered include neurons, nerve tissue, the brain and spinal cord, reflex action, communication between neurons, graded potentials, action potentials, and homeostasis. The summary focuses on the essential information about the structure and function of the nervous system.
Nervous anatomy sem2 [compatibility mode]
The document describes the divisions of the vertebrate nervous system. It discusses the central nervous system which includes the brain and spinal cord. The peripheral nervous system is outside the brain and spinal cord and has two divisions: the somatic nervous system and the autonomic nervous system. The autonomic nervous system controls organs like the heart and intestines and has sympathetic and parasympathetic parts. The document then goes into detail about parts of the brain like the cerebrum, cerebellum, brain stem, and various lobes. It discusses the functions of different brain regions and how the brain areas work together as a whole system.
L Nervous System
The document provides information on the central nervous system (CNS) and peripheral nervous system (PNS). It discusses that the CNS is made up of neurons and neuroglia cells and is divided into the brain and spinal cord. The PNS has sensory and motor divisions that bring sensory information to and motor commands from the CNS. The cellular organization of the nervous system includes neurons and neuroglia cells such as astrocytes, oligodendrocytes, microglia, ependymal cells, and Schwann cells.
Similar to reticular formation.pptx (20)
Nerve PPT BPHARM 1ST YEAR HUMAN ANATOMY PHYSIOLOGY.PPT
Nerve PPT BPHARM 1ST YEAR HUMAN ANATOMY PHYSIOLOGY.PPT
Recently uploaded
What are the different types of Dental implants.
Are you looking for a long-lasting solution to your missing tooth?
Dental implants are the most common type of method for replacing the missing tooth. Unlike dentures or bridges, implants are surgically placed in the jawbone. In layman’s terms, a dental implant is similar to the natural root of the tooth. It offers a stable foundation for the artificial tooth giving it the look, feel, and function similar to the natural tooth.
Skin Diseases That Happen During Summer.
Summer is a time for fun in the sun, but the heat and humidity can also wreak havoc on your skin. From itchy rashes to unwanted pigmentation, several skin conditions become more prevalent during these warmer months.
Ageing, the Elderly, Gerontology and Public Health
Challenges associated with ageing from a public health perspective
Lecture 6 -- Memory 2015.pptlearning occurs when a stimulus (unconditioned st...
learning occurs when a stimulus (unconditioned stimulus) eliciting a response (unconditioned response) • is paired with another stimulus (conditioned stimulus)
How to choose the best dermatologists in Indore.
The skin is the largest organ and its health plays a vital role among the other sense organs. The skin concerns like acne breakout, psoriasis, or anything similar along the lines, finding a qualified and experienced dermatologist becomes paramount.
The Nervous and Chemical Regulation of Respiration
These lecture slides, by Dr Sidra Arshad, offer a simplified look into the mechanisms involved in the regulation of respiration:
Learning objectives:
1. Describe the organisation of respiratory center
2. Describe the nervous control of inspiration and respiratory rhythm
3. Describe the functions of the dorsal and respiratory groups of neurons
4. Describe the influences of the Pneumotaxic and Apneustic centers
5. Explain the role of Hering-Breur inflation reflex in regulation of inspiration
6. Explain the role of central chemoreceptors in regulation of respiration
7. Explain the role of peripheral chemoreceptors in regulation of respiration
8. Explain the regulation of respiration during exercise
9. Integrate the respiratory regulatory mechanisms
10. Describe the Cheyne-Stokes breathing
Study Resources:
1. Chapter 42, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 36, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 13, Human Physiology by Lauralee Sherwood, 9th edition
How to Control Your Asthma Tips by gokuldas hospital.
Respiratory issues like asthma are the most sensitive issue that is affecting millions worldwide. It hampers the daily activities leaving the body tired and breathless.
The key to a good grip on asthma is proper knowledge and management strategies. Understanding the patient-specific symptoms and carving out an effective treatment likewise is the best way to keep asthma under control.
Pharmacology of 5-hydroxytryptamine and Antagonist
5-hydroxytryptamine or 5-HT or Serotonin is a neurotransmitter that serves a range of roles in the human body. It is sometimes referred to as the happy chemical since it promotes overall well-being and happiness.
It is mostly found in the brain, intestines, and blood platelets.
5-HT is utilised to transport messages between nerve cells, is known to be involved in smooth muscle contraction, and adds to overall well-being and pleasure, among other benefits. 5-HT regulates the body's sleep-wake cycles and internal clock by acting as a precursor to melatonin.
It is hypothesised to regulate hunger, emotions, motor, cognitive, and autonomic processes.
NAVIGATING THE HORIZONS OF TIME LAPSE EMBRYO MONITORING.pdf
Time-lapse embryo monitoring is an advanced imaging technique used in IVF to continuously observe embryo development. It captures high-resolution images at regular intervals, allowing embryologists to select the most viable embryos for transfer based on detailed growth patterns. This technology enhances embryo selection, potentially increasing pregnancy success rates.
Medical Quiz ( Online Quiz for API Meet 2024 ).pdf
This quiz was conducted as a promotional event for the 2024 Annual Meet of Kerala Chapter of API.
More than 20 participants took part everyday !
Pollen and Fungal allergy: aeroallergy.pdf
Pollen and Fungal allergy: aeroallergy.pdfChulalongkorn Allergy and Clinical Immunology Research Group
Pollen and Fungal allergy
Presented by Chaloemchai Chumsaengchotsakul, MD.
June 14, 202410 Benefits an EPCR Software should Bring to EMS Organizations
The benefits of an ePCR solution should extend to the whole EMS organization, not just certain groups of people or certain departments. It should provide more than just a form for entering and a database for storing information. It should also include a workflow of how information is communicated, used and stored across the entire organization.
Histololgy of Female Reproductive System.pptx
Dive into an in-depth exploration of the histological structure of female reproductive system with this comprehensive lecture. Presented by Dr. Ayesha Irfan, Assistant Professor of Anatomy, this presentation covers the Gross anatomy and functional histology of the female reproductive organs. Ideal for students, educators, and anyone interested in medical science, this lecture provides clear explanations, detailed diagrams, and valuable insights into female reproductive system. Enhance your knowledge and understanding of this essential aspect of human biology.
Cosmetology and Trichology Courses at Kosmoderma Academy PRP (Hair), DR Growt...
Cosmetology and Trichology Courses at Kosmoderma Academy PRP (Hair), DR Growt...Kosmoderma Academy Of Aesthetic Medicine
Kosmoderma Academy, a leading institution in the field of dermatology and aesthetics, offers comprehensive courses in cosmetology and trichology. Our specialized courses on PRP (Hair), DR+Growth Factor, GFC, and Qr678 are designed to equip practitioners with advanced skills and knowledge to excel in hair restoration and growth treatments.
Test bank for karp s cell and molecular biology 9th edition by gerald karp.pdf
Test bank for karp s cell and molecular biology 9th edition by gerald karp.pdf
Test bank for karp s cell and molecular biology 9th edition by gerald karp.pdf
Test bank for karp s cell and molecular biology 9th edition by gerald karp.pdf
Osteoporosis - Definition , Evaluation and Management .pdf
Osteoporosis is an increasing cause of morbidity among the elderly.
In this document , a brief outline of osteoporosis is given , including the risk factors of osteoporosis fractures , the indications for testing bone mineral density and the management of osteoporosis
Recently uploaded (20)
Ageing, the Elderly, Gerontology and Public Health
Ageing, the Elderly, Gerontology and Public Health
Lecture 6 -- Memory 2015.pptlearning occurs when a stimulus (unconditioned st...
Lecture 6 -- Memory 2015.pptlearning occurs when a stimulus (unconditioned st...
The Nervous and Chemical Regulation of Respiration
The Nervous and Chemical Regulation of Respiration
How to Control Your Asthma Tips by gokuldas hospital.
How to Control Your Asthma Tips by gokuldas hospital.
Pharmacology of 5-hydroxytryptamine and Antagonist
Pharmacology of 5-hydroxytryptamine and Antagonist
NAVIGATING THE HORIZONS OF TIME LAPSE EMBRYO MONITORING.pdf
NAVIGATING THE HORIZONS OF TIME LAPSE EMBRYO MONITORING.pdf
Medical Quiz ( Online Quiz for API Meet 2024 ).pdf
Medical Quiz ( Online Quiz for API Meet 2024 ).pdf
10 Benefits an EPCR Software should Bring to EMS Organizations
10 Benefits an EPCR Software should Bring to EMS Organizations
Cosmetology and Trichology Courses at Kosmoderma Academy PRP (Hair), DR Growt...
Cosmetology and Trichology Courses at Kosmoderma Academy PRP (Hair), DR Growt...
Test bank for karp s cell and molecular biology 9th edition by gerald karp.pdf
Test bank for karp s cell and molecular biology 9th edition by gerald karp.pdf
Osteoporosis - Definition , Evaluation and Management .pdf
Osteoporosis - Definition , Evaluation and Management .pdf
reticular formation.pptx
- 2. Learning objectives Reticular formation nuclei Reticular pathways Physiology of Reticular activating system Functions of Reticular formation.
- 3. Reticular formation Dense network of neurons and nerve fibers found in Core of brainstem Indinstinct , not well defined anatomically. 50-80 nuclear masses It can be: Midbrain, Pontine and Medullary RF. Consists of : Aggregates of Neurons Afferent and Efferent connections.
- 7. Reticular formation The neurons have long dendrites and axons.
- 8. Reticular formation NUCLEAR COLUMNS: Median column: Raphe nuclei in midbrain Median Column: MAGNOCELLULAR Nucleus gigantocellularis in medulla and pontine tegmental nuclei.
- 9. Reticular formation Lateral columns: PARVOCELLULAR Central nucleus of medulla and pons
- 10. Reticular formation Cardiac centers Respiratory centers Vasomotor centers Salivatory centers Chemoreceptor neurons.
- 11. Reticular formation They receive afferents from spino-reticular tracts. Fibers from this part project upwards as Reticular activating system. Fibers from this part project downwards as medial and lateral reticulospinal tracts.
- 12. Reticular pathways Connections of RF: Afferent connections Efferent connections: Ascending and Descending projections.
- 13. Reticular formation Afferents: Receives afferents from almost all ascending sensory pathways Optic pathway Olfactory pathway Auditory pathway Taste pathway Spinal and Trigeminal pathway Pain, temperature, vibration and kinesthetic sensation. Cerebral cortex Cerebellum Corpus striatum Thalmic nuclei
- 15. Reticular pathways Cortico-reticulo-spinal pathways: Cortico-reticulo-cerebellar Cortico-reticulo-basal ganglia Visceral control pathways: control of respiration , heart rate and BP RAS-Reticular activating system.
- 16. Reticular pathways RAS: Also called ARAS from brain stem RF. Polysynaptic pathway Also receives collaterals from: Spinothalamic tracts Trigeminal, auditory , visual and olfactory pathway systems.
- 17. Reticular pathways From RAS fibers go to non-specific thalamic nuclei(intralaminar and midline nuclei) From the thalamus the fibers are projected diffusely and non specifically to whole cortex. Some fibers bypass the thalamus to project to whole cortex. RAS is non specific system since it can be stimulated by any sensation from collaterals. It also receives facilitatory feedback impules from motor cortex and inhibitory feedback impulses from limbic system.
- 18. Reticular pathways Functions of ARAS: Facilitatory to central neurons –increases excitability. Wakefulness and alertness Beta rhythm in ECG. Applied aspects: Lesions in RAS-Sleep and coma Benzodiazepines and babituraes prevent synaptic transmission in RAS.
- 19. Neurotransmitters of Reticular formation. Cholinergic neurons : mid brain and pons to cortex Adrenergic neurons: whole of RF to thalamus to cortex Nor adrenergic neurons: locus coerulus to cerebellum Dopaminergic neurons : midbrain RF to basal ganglia Serotonergic neurons: Raphe nuclei to thalamus, cerebral cortex , thalamus and limbic system From raphe nuclei to spinal cord (control the transmission of pain)
- 20. Reticular formation Functions: Sleep wakefulness: serotonin-secreting neurons in raphe nuclei mediate non-REM sleep Conditioning and learning: Neural substrate Selective attention and sensory inattention: FILTER Control of muscle tone and regulation of postural reflex changes: RF modulates the tone of extensor muscles. Pontine RF has excitatory and Medullary reticulospinal tract has inhibitory influence on extensor muscle tone.
- 21. Reticular formation Autonomic functions: Cortical neurons Through Visceral regulating centers influences the autonomic functions Modulation of Pain: Raphe nuclei fibers going to spinal cord (substantial gelatinosa) modulate the perception of pain. Control of neuroendocrine system: control the neuroendocrine system in hypothalamus.