Chapter 4 Anatomy Of The Nervous System Flashcards
What makes up gray matter? White matter? 4.1
4.1
Gray matter is the centre of the chord in an “H” and is densely packed with cell bodies and dendrites
White matters consists mostly of myelinated axons
Draw a cross section of the spinal cord, including sensory and motor nerves, dorsal and ganglia, and dorsal and ventral directions. 4.1
4.1
What are the two parts of the autonomic nervous system? Give the location and the function of each. 4.1
4.1
Two parts of the autonomic nervous system consist of the sympathetic nervous system and the parasympathetic nervous system.
Sympathetic-prepare body for fight or flight
it is a network of nerves that prepares the organs for vigourous activity, consists of chains of ganglia just to the left and right of the spinal cords central regions. These ganglia are connected by axons to the spinal cord
the Parasypathetic- facilitates non-emergency response, actions are opposite that of the sympathetic system. Consists of cranial nerves and nerves from the sacral spinal cord.
Which transmitter is used by the post ganglionic parasympathetic nerves? Which is used by most sympathetic post ganglionic nerves? 4.1
4.1
Post ganglionic axons release neurotransmitter acetylcholine
Post ganglionic synapses of sympathetic nervous system uses norepinephrine (few use acteylcholine-sweat glands)
What are the three components of the hindbrain? Give one specialty of each. 4.1
4.1
medulla: controls vital reflexes-breathing, heart rate, vomitting, salivation, coughing, sneezing.
the pons- acts as a bridge-axons from each 1/2 of the brain cross to opposite side L hemisphere controls the R side of the body
The cerebellum- controls movement
What are cranial nerves? Where are their nuclei? 4.1
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control sensations from the head, muscle movements in the head and the parasympathetic output organs
Their nuclei are located in the medulla just above the spinal cord.
What are the anatomical location and functions of the reticular and the raphe system? 4.1
4.1
Located in the medulla and pons
reticular formation has descending and ascending portions
descending portion is one of several brain areas that control the motor areas of the spinal cord
ascending portion sends output to much of the cerebral cortex selectively increasing arousal and attention in one area or another
What are the two major divisions of the midbrain? Name two structures in each division. 4.1
4.1
roof of midbrain called the tectum- superior colliculus and inferior colliculus-sensory processing
under the tectums is the tegmentum- includes nuclei for 3rd and 4th cranial nerves, parts of reticular formation and extensions of pathways between forebrain and spinal cord
Re: the forebrain
What are the major structures comprising the limbic system? What are the general functions of this interconnected system? 4.1
4.1
Limbic system is a number of structures that form a border around the brainstem
includes olfactory bulb, hypothalamus, hippocampus, amydala, and cingulate gyrus of the cerebral cortex
important for motivations and emotions such as eating, drinking and sexual activity, and anxiety and aggression
Describe the relationship of the thalmus to the cerebral cortex. (Of the forebrain) 4.1
4.1
thalamus and hypothalamus=encephalon
thalamus is a pair of structures (L and R) in the centre of the forebrain that resembles two avocados joined side by side- one in L hemisphere and the other in the R
Where is the hypothalamus and what kinds of behaviour does it help regulate? (4.1)
4.1
small area near base of brain just ventral to the thalamus
conveys messages to the pituitary gland altering its release of hormones.
damage to the is causes abnormalities in the motivated behaviour such as feeding, drinking, temp regulation etc.
Where is the pituitary? What is its function? What structue largely controls it? (Forebrain) 4.1
4.1
is an endocrine gland (hormone producing)
located at base of hypothalamus attached by a stalk that contains neurons, blood vessels and connective tissues
controlled by the hypothalamus which tells it what to synthesize.
Where are the basal ganglia? Which structures make up the basal ganglia? Briefly describe their function. (Forebrain) 4.1
4.1
Group of subcortical structures lateral to the thalamus.
Includes 3 major structures:
1. caudate nucleus
2. putamen
3. globus pallidus
These are critical for learning and remembering.
Where is the hippocampus? To what psychological process has it been linked? (Forebrain) 4.1
4.1
large structures between the thalamus and cerebral cortex mostly toward the posterior of the forebrain.
Critical for storing certain kinds of memories especially memories for individual events.
Damage = difficulty storing new memories.
What are the ventricles? Where is the cerebrospinal fluid formed? In which direction does it flow? Where is it reabsorbed into the blood vessels? 4.1
4.1
The ventricles are 4 fluid filled cavities within the brain. Each hemisphere contains a lateral ventricle and toward the posterior they connect to the third ventricle positioned at the midline separating the left from the right thalamus.
The third ventricle connects to the fourth ventricle in the centre of the medulla.
Wat are the functions of the CSF? (Ventricles) 4.1
4.1
CSF is the clear fluid that fills the ventricles.
Flows from lateral ventricles to the 3rd and 4th ventricles and some flows to the central canal of the spinal cord but more goes to the narrow spaces between the brain and the thing meninges, membranes that surround the brain and the spinal cord.
Function: it cushions the brain against mechanical shock.
What is the relationship of gray matter to white in the cortex?
Compare this relationship to that in the spinal cord.
4.2
4.2
Gray matter: are the cells of the cerebral cortex their axons extending inward are the white matter
The spinal cord is opposite with the white matter on the outside and gray matter on the inside in sort of an H shape.
How many layers (laminae) does human neocortex have?
Describe the input to lamina IV and the output from lamina V
4.2
4.2
Laminae: the human neocortex has up to 6 laminae.
These are layers of cell bodies that are parallel to the surface of the cortex and separated from each other by layers of fibres
Lamina V, which sends long axons to the spinal cord and other distant areas has the greatest control of the muscles.
Laminal IV receives axons from various sensory nuclei of the thalamus is prominent in all the primary sensory areas (visual, auditory and somatosensory) but absent from the motor cortex.
What is the relationship of columns to laminae?
What can be said about all the celts within one column?
4.2
the columns are cells perpendicular to the laminae. They have similar properties to one another.
What are the location and functions of the occipital lobe?
4.2
4.2
Location: at the posterior or caudal end of the cortex.
Function: main target for visual info.
A Person with cortical blindness has normal eyes and pupillary reflexes but no conscious visual perception and no imagery not even in dreams. A person with eye damage and have intact occipital cortex can still imagine visual scenes.
What are the location and functions of the parietal lobe?
4.2
4.2
Location: lies between the occipital lobe and the central sulcus (one of the deepest grooves in the surface of the cortex.
The area just posterior to the central sulcus, the post central gyrus or the primary somatosensory cortex receives sensations from touch receptors, muscle stretch receptors and joint receptors.
Where is the temporal lobe? What are some temporal lobe functions?
4.2
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Location: the lateral portion of each hemisphere near the temples
Function: auditory information area.
What are the location and functions of the frontal lobe?
Distinguish between the precentral gyrus and the prefrontal cortex.
4.2
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The primary motor cortex and the prefrontal cortex.
Extends from the central sulcus to the anterior limit of the brain.
Controls fine movement such are moving one finger at a time.
What were the results of prefrontal lobotomies?
4.2
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Apathy
Loss of an ability to plan and take initiative.
Memory disorders
distractibility and loss of emotional expressions.
Lose their social inhibitions
Ignoring the rules of polite civilized conduct.
What is the difference between working memory and reference memory?
Which shows greater impairment after prefrontal lesions?
4.2
4.2
Working memory in prefrontal cortex.
Ability to remember recent events such as where you parked your car or was talking about before being interrupted.
What is the delayed response task, and how is it affected by prefrontal lesions? Is this primarily a test of working or reference memory?
4.2
4.2
A task where they see or hear something then have to respond later.
People with prefrontal lesions have trouble with these tasks.
How would you answer the question of whether the brain operates as an undifferentiated whole or a collection of independent parts?
4.2
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What is the binding problem? (Re: how do the pieces of the brain work together?)
4.2
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Question of how the brain areas produce a perception of a single object is known as the binding problem. Aka large scale integration problem.
What are gamma waves?
What may be the role fo the inferior temporal cortex in binding the different aspects of sensory objects?
4.2
4.2
Gamma waves is a pattern of neural oscillation in humans with frequency between 25 and 100 Hz though 40 is typical.
Gamma waves may be implicated in creating the unity of conscious perception
(From Wikipedia)
What is the Bell-Magendie Law? 4.1
4.1
entering dorsal roots (axons bundles) carry sensory information and the exiting ventral roots carry motor information.
axons to and from skiing and muscles are the peripheral nervous system
cell bodies of the sensory neurone are in clusters called dorsal root ganglia
Ablation
removal of a brain area, generally with a surgical knife
Autonomic nervous system
part of the PNS that controls the heart, intestines, and other organs
Basal forebrain
area anterior and dorsal to the hypothalamus; includes cell clusters that promote wakefulness and sleep
Basal ganglia
a group of subcortical forebrain structures lateral to the thalamus
Bell-Magendie law
the concept that the entering dorsal roots carry sensory information and the exiting ventral roots carry motor information
Binding problem
question of how various brain areas produce a perception of a single object
Brainstem
the medulla, pons, midbrain, and central structure of the forebrain
Broca’s area
portion of the brain that is associated with language production
Central canal
a fluid-filled channel in the center of the spinal cord
Central nervous system (CNS)
the brain and the spinal cord
