Chapter 3 Flashcards
1
Q
What are the two basic divisions of the nervous system?
A
- Central nervous system (CNS)
- Peripheral nervous system (PNS)
2
Q
Where is the central nervous system located?
A
- Brain
- Spinal cord
3
Q
What does the central nervous system do?
A
Controls most functions of the body and mind
4
Q
What are the two divisions of the peripheral nervous system?
A
- Somatic nervous system
- Autonomic nervous system
5
Q
What does the somatic aspect of the peripheral nervous system control?
A
- Controls voluntary muscles
- Conveys sensory information to CNS
- Interacts with the external environment
6
Q
What does the afferent nerves of the somatic aspect of the peripheral nervous system do?
A
- Carry sensory signals from the skin, skeletal muscles, joints, eyes, ears, etc., to the CNS
- Going towards the CNS; arrive
7
Q
What does the efferent nerves of the somatic aspect of the peripheral nervous system do?
A
- Carry motor signals from the CNS to the skeletal muscles
- Going away from the CNS; exit
8
Q
What does the autonomic aspect of the peripheral nervous system control?
A
- Controls involuntary muscles
- Fight or flight (sympathetic)
- Rest and digest (parasympathetic)
9
Q
What is an example of an autonomic aspect of the peripheral nervous system function?
A
Regulating the body’s internal environment
10
Q
What does the efferent nerves of the autonomic aspect of the peripheral nervous system do?
A
- Carry motor signals from the CNS to internal organs
- Two types: Sympathetic/parasympathetic
11
Q
What does the sympathetic efferent nerves of the autonomic aspect of the peripheral nervous system do?
A
- Fight or flight
- Energy expanding
- Fires less since you aren’t in a constant state of fear/nervousness
12
Q
What does the parasympathetic efferent nerves of the autonomic aspect of the peripheral nervous system do?
A
- Rest and digest
- Energy conserving
- Fires more since you aren’t in a constant state of fear/nervousness
13
Q
What does the afferent nerves of the autonomic aspect of the peripheral nervous system do?
A
Carry sensory signals from internal organs to the CNS
14
Q
Which nervous system is more protected than the other?
A
Central nervous system
15
Q
What makes the CNS better protected than the PNS?
A
- Mechanical protection: Skull and meninges (dura mater, arachnoid, pia mater layers), vertebrae, cerebrospinal fluid (buffer/shock absorber)
- Immunological protection: Blood-brain barrier
16
Q
Which nervous system can regenerate while the other cannot?
A
The peripheral nervous system can
17
Q
How does the PNS regenerate itself?
A
- Schwann cells form lines and reconnect
- Axons regrow as long as the soma is intact
18
Q
What is the blood brain barrier (BBB), physically?
A
A highly selective permeable border made of tightly packed cells
19
Q
What purpose does the blood brain barrier (BBB) serve?
A
Protects the brain from circulating pathogens
20
Q
Dorsal (posterior)
A
Toward or at the back of the body
21
Q
Ventral (anterior)
A
Toward or at the front of the body
22
Q
Lateral
A
Away from the midline of the body
23
Q
Medial
A
Toward or at the midline of the body
24
Q
Caudal (inferior)
A
Away from the head or toward the lower part of a structure or the body (below)
25
Rostral
Towards the nose/beak
26
Major parts of a neuron
- Cell membrane
- Cell body
- Dendrites
- Axon hillock
- Axon
- Myelin
- Nodes of Ranvier
- Buttons
- Synapses
27
Cell membrane
Cell body
The semipermeable membrane that encloses the neuron `
The metabolic center of the neuron; also called the soma
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Dendrites
The short processes emanating from the cell body, which receive most of the synaptic contacts from other neuronshttps://quizlet.com/cdn-cgi/image/f=auto,fit=cover,h=200,onerror=redirect,w=240/https://o.quizlet.com/7PAjP4araS-vTd2JMISgpA.png
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Axon hillock
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The cone-shaped region at the junction between the axon and the cell body
30
Axon
The long, narrow process that projects from the cell body
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31
Myelin
The fatty insulation around many axons
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32
Nodes of Ranvier
The gaps between sections of myelin
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33
Buttons
The button-like endings of the axon branches, which release chemicals into synapses
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34
Synapses
The gaps between adjacent neurons across which chemical signals are transmitted
35
What are the major types of proteins that are embedded in a neuron's lipid bilayer membrane?
- Ion channels
- Receptors
- Transporters
36
What is the role of an ion channel that is embedded in a neuron's lipid bilayer membrane?
Regulate cation + / cation - flow in/out of cell
37
What is the role of a receptor that is embedded in a neuron's lipid bilayer membrane?
- Neurotransmitters bind to them
- Signal excitation (+, increase firing)
- Signal inhibition (-, decrease firing)
38
What is the role of transporters that are embedded in a neuron's lipid bilayer membrane?
- Actively move important molecules in/out of the cell
| - Ex. Na+ / K+ transporter
39
Major cations involved with learning/memory and neurotransmitter release
- Na+
- Ca+
- K+
- Mg+
40
Major anion involved with learning/memory and neurotransmitter release
Cl-
41
What are the 3 glial cells in the CNS
- Oligodendrocytes
- Microglia
- Astrocytes
42
Oligodendrocytes
- Glial cell in the CNS
| - Produce myelin sheath
43
Microglia
- Glial cell in the CNS
- Respond to injury/disease
- Clean up: Trigger inflammation, regulate synapse formation and elimination
44
Astrocytes
- Glial cell in the CNS
| - Contribute to the blood brain barrier, regulate blood flow
45
What glial cell is in the PNS
Schwann cells
46
Schwann cells
- Glial cell in PNS
| - Produces the myelin sheath and results in direct axonal regrowth after injury
47
What are the 3 major divisions of the brain?
- Hindbrain
- Midbrain
- Forebrain
48
What is located in the hindbrain?
- Medulla
- Pons
- Cerebellum
- C on picture
the lower bottom bulb
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49
What is the main function of the hindbrain?
Handles the primitive parts without you realizing it
50
Medulla
- Part of the hindbrain
- Autonomic
- Basic life support functions (breathing, heartbeat, digestion, swallow/cough/vomit)
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51
When people OD on opioids it makes it hard for the body to function normally and care for itself. Where do the opioids bind to the neurons?
Medulla
52
Pons
- Soma of "reticular activating" neurons
- Responsible for wakefulness (Raphe) /alertness (Locus Coeruleus)
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53
Locus coeruleus
- Used in the pons
- Keeps individuals alert
- Norepinephrine releasing
54
Raphe
- Used in the pons
- Sleep/wake cycle
- 5-HT-releasing
55
A drug that induces (heightens) the levels of locus coeruleus and raphe in the pons would result in:
Insomnia
56
Cerebellum
- Part of the hindbrain
- Motor coordination/balance (execution of learned motor sequences, largely unconscious during execution)
- Practice develops circuitry in the cerebellum
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57
What could result from a tiny stroke in the cerebellum?
- Loss of coordination for well known movements
| - An individual losing the ability to stand/walk correctly
58
E.B. has a tumor growing in his brain. Although he has been an excellent salsa dancer for many years, he is having more and more trouble getting the timing and sequence (pattern) of the steps right. Where is the tumor most likely to
be located?
Cerebellum
59
What 3 nuclei are located in the midbrain?
- Periaqueductal gray (PAG)
- Ventral tegmental area (VTA)
- Substantia nigra
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60
Superior colliculus
- Part of the midbrain/tectum
- Visual coordination of movement
- When you see something odd it makes you want to look at it
61
Inferior colliculus
- Part of the midbrain/tectum
- Sound localization; auditory coordination of movement
- When you hear a loud boom it will make you look
62
Periaqueductal gray (PAG)
- Part of the midbrain/tegmentum
- Pain modulation/control area of the brain
- Opioids bind here and disinhibit it
63
Ventral tegmental area (VTA)
- Part of the midbrain/tegmentum
- Pleasure/motivated behavior
- Major dopamine creating/releasing
64
Someone who doesn't want to do anything and experiences little enjoyment most likely has something wrong with their:
Ventral tegmental area (VTA)
65
Substantia nigra
- Part of the midbrain/tegmentum
- Speed of movement
- Dopamine releasing
66
What neuron does Parkinson's disease affect?
Substantia nigra
67
What is located in the forebrain?
- Thalamus
- Hypothalamus
- Basal ganglia
- Amygdala
- Hippocampus
- Cerebrum (4 lobes)
68
Thalamus
- Part of the forebrain
- Sensory motor "relay/coordinating station"
- Wanting to move right big toe
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69
What can damage to the thalamus result in?
- Movement disorders
| - Lack of movement
70
Hypothalamus
- Part of the forebrain
- 4F's: Feeding, fornication, fight, flight
- Sympathetic nervous system activation starts here
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71
What can damage to the hypothalamus result in?
Disruptions in body temperature regulation, growth, weight, emotions
72
Basal ganglia
- Part of the forebrain
| - Habitual movement
73
Examples of basal ganglia movements
- Swatting away a fly
- OCD
- Having a tick
74
Example of a hypothalamus function
Waking up hot (past normal time of waking up) and wanting to throw off blankets
75
What disease affects the basal ganglia?
- Huntington's disease
- Uncontrolled movement caused by deterioration of this brain area
- Arms don't stop moving, ultimately develop dementia
76
Amygdala
- Part of forebrain
| - Emotions (particularly fear and anger)
77
What would damage to the amygdala cause?
Emotional sensitivity
78
L.C. has become increasingly aggressive over the past few months, often getting into fights after very little provocation. What part of L.C.'s brain may be malfunctioning?
Amygdala
79
Hippocampus
- Part of the forebrain
| - Learning/memory
80
Example of damage to the hippocampus
- H.M.
| - They took part of this brain area out and cured his epilepsy, but he was incapable of learning new things
81
P.D. recently started taking medication to control epilepsy. Unfortunately, she now finds that she really struggles with coursework; she is spending even more time studying but often has trouble remembering much of what she read the night before? The medication is probably impairing what part of P.D. 's brain?
Hippocampus
82
What are the 4 lobes of the cerebrum
- Occipital lobe
- Parietal lobe
- Temporal lobe
- Frontal lobe
83
Occipital lobe
- Part of the cerebrum/forebrain
- Simple visual perception
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84
Parietal lobe
- Part of the cerebrum/forebrain
- Somatosensory perception (anterior)
- Complex visual perception (posterior)
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Temporal lobe
- Part of the cerebrum/forebrain
- Complex visual perception
- Auditory perception
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Frontal lobe
- Part of the cerebrum/forebrain
- Decision making/reasoning: Prefrontal cortex (anterior)
- Planning/control on conscious movement: Motor cortex (posterior)
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What does the prefrontal cortex of the frontal lobe do?
Decision making/reasoning
88
What does the motor cortex of the frontal lobe do?
Planning/control on conscious movement
89
What might damage to the cerebrum result in?
- Personality disorders
| - Loss of senses
90
S.L. & E.G. each swallow a pill. A half hour later a friend asks them if they want to go to College Hill party, a movie, or stay home. They simply cannot make a decision; they're having trouble holding all options in mind at the same time. What part of their brains have probably been affected by the pill?
Prefrontal cortex
91
Homunculus arrangement
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92
Motor and sensory systems are said to be mostly "crossed over" - what does this mean?
- Primary motor cortex axons → crossover at medulla → controls muscles on the other side of the body
- Somatosensory neurons on one side of body axons → crossover in spinal cord → ascent to thalamus, somatosensory cortex on the other side of the brain
93
What neurons almost completely crossover to the other side of the brain?
- Visual neurons
| - Auditory neurons
94
If a stroke affects the left side of the body, then the stroke most likely occurred on the __ hemisphere of the brain
Right
95
The ________ nervous system is composed of the brain and the spinal cord.
central
96
Twelve pairs of ________________ project from the brain.
cranial nerves
97
________ nerves stimulate, organize, and mobilize energy resources in threatening situations.
Sympathetic
98
________ is continuously produced by the choroid plexuses.
Cerebrospinal fluid
99
The ________ blocks the entry of many large molecules into brain tissue from the circulatory system.
blood–brain barrier
100
The neuron cell membrane is composed of a:
lipid bilayer.
101
____________ proteins are proteins through which certain molecules can pass.
Channel
102
A neuron with two processes extending from its cell body is classified as a:
bipolar neuron.
103
Myelin sheaths are produced by _______________ in the central nervous system and by ________________ in the peripheral nervous system.
oligodendrocytes; Schwann cells
104
One difference between Schwann cells and oligodendrocytes is that Schwann cells:
constitute a single myelin segment, whereas oligodendrocytes constitute multiple segments.
105
The __________________ stain will invade only a few neurons in each slice of tissue and color each invaded neuron entirely black.
Golgi
106
____________ dyes are often used to estimate the number of cell bodies in an area.
Nissl
107
_______________ tracing methods are used to trace the paths of axons projecting away from cell bodies located in a particular area.
Anterograde
108
Posterior is to caudal as _______________ is to rostral.
anterior
109
____________ means closer to the CNS, whereas _______ means farther from the CNS.
Proximal; distal
110
With respect to the spinal cord, gray matter is to _____ as white matter is to ______.
cell bodies; axons
111
The pons and the cerebellum make up the:
metencephalon.
112
The cerebellum is BEST described as playing a role in ______ functions.
both sensorimotor and cognitive
113
In the developing brain, the _________________ is anterior to the diencephalon.
telencephalon
114
Which brain structure is thought to play a role in the rewarding effects of addictive drugs and other reinforcers?
nucleus accumbens
115
The ____________________ nervous system is the part of the PNS that interacts with the external environment. It is composed of __________ nerves that carry sensory signals to the central nervous system and _________ nerves that carry motor signals from the central nervous system to the skeletal muscles.
somatic; afferent; efferent
116
The degree to which therapeutic or recreational drugs can influence brain activity depends on the ease with which they penetrate the:
blood–brain barrier.
117
Neurons with a short axon or no axon at all are called:
interneurons.
118
_____________ are glial cells that respond to injury or disease by multiplying, and then engulfing cellular debris or even entire cells.
Microglia
119
_____________________ methods are used when an investigator wants to trace the paths of axons projecting into a particular area.
Retrograde tracing
120
Superior is to inferior as _____ is to _____.
top; bottom
121
____________ matter is composed largely of cell bodies and unmyelinated interneurons.
Gray
122
Pairs of spinal nerves are attached to the spinal cord at _________ different levels of the spine.
31
123
Dorsal root axons are sensory unipolar neurons with their cell bodies grouped together just outside the cord to form the dorsal:
root ganglia.
124
There are three swellings that occur at the anterior end of a fluid-filled tube in the developing embryo. These three swellings eventually develop into the adult:
forebrain, midbrain, and hindbrain.
125
With respect to the adult human brain, which choice accurately locates one of the major divisions reviewed in the text?
metencephalon – hindbrain
126
In humans and in other higher vertebrates, the ____________ undergoes the MOST growth during development.
telencephalon
127
The myelencephalon is commonly referred to as the:
medulla.
128
The _________________ is an area of cortex that is not neocortex—it has only three layers.
hippocampus
129
________________ are large multipolar neurons with pyramid-shaped cell bodies.
Pyramidal cells
130
Dorsal
Toward the surface of the back of a vertebrate or toward the top of the head.
131
Central nervous system (CNS)
The portion of the nervous system within the skull and spine.
132
Peripheral nervous system (PNS)
The portion of the nervous system outside the skull and spine.
133
Somatic nervous system (SNS)
The part of the peripheral nervous system that interacts with the external environment.
134
Afferent nerves
Nerves that carry sensory signals to the central nervous system.
135
Efferent nerves
Nerves that carry motor signals from the central nervous system to the skeletal muscles or internal organs.
136
Autonomic nervous system (ANS)
The part of the peripheral nervous system that participates in the regulation of the body’s internal environment.
137
Sympathetic nerves
Those motor nerves of the autonomic nervous system that project from the central nervous system in the lumbar and thoracic region areas of the spinal cord.
138
Parasympathetic nerves
Those autonomic motor nerves that project from the brain to the sacral region of the spinal cord.
139
Cranial nerves
The 12 pairs of nerves extending from the brain (e.g., optic nerves, olfactory nerves, and vagus nerves).
140
Glial cells
Several classes of nonneural cells of the nervous system.
141
Oligodendrocytes
Glial cells that myelinate axons of the central nervous system; also known as oligodendroglia.
142
Myelin
A fatty insulating substance.
143
Myelin sheaths
Coverings on the axons of some neurons that are rich in myelin and increase the speed and efficiency of axonal conduction.
144
Schwann cells
The glial cells that compose the myelin sheaths of PNS axons and promote the regeneration of PNS axons.
145
Microglia
Glial cells that respond to injury or disease by engulfing cellular debris and triggering inflammatory responses.
146
Astrocytes
Large, star-shaped glial cells that play multiple roles in the central nervous system.
147
Golgi stain
A neural stain that completely darkens a few of the neurons in each slice of tissue, thereby revealing their silhouettes.
148
Nissl stain
A neural stain that has an affinity for structures in neuron cell bodies.
149
Electron microscopy
A microscopy technique used to study the fine details of cellular structure.
150
Anterior
Toward the nose end of a vertebrate.
151
Posterior
Toward the tail end of a vertebrate or toward the back of the head.
152
Dorsal
Toward the surface of the back of a vertebrate or toward the top of the head.
153
Ventral
Toward the chest surface of a vertebrate or toward the bottom of the head.
154
Medial
Toward the midline of the body.
155
Lateral
Away from the midline of the body of a vertebrate, toward the body’s lateral surfaces.
156
Superior
Toward the top of the primate head.
157
Inferior
Toward the bottom of the primate head or brain.
158
Proximal
Close to something.
159
Distal
Far from something.
160
Horizontal sections
Any slices of brain tissue cut in a plane that are parallel to the top of the brain.
161
Frontal sections
Any slices of brain tissue cut in a plane that is parallel to the face; also termed coronal sections.
162
Sagittal sections
Any slices of brain tissue cut in a plane that is parallel to the side of the brain.
163
Cross section
Section cut at a right angle to any long, narrow structure of the central nervous system.
164
Gray matter
Portions of the nervous system that are gray because they are composed largely of cell bodies and unmyelinated interneurons.
165
White matter
Portions of the nervous system that are white because they are composed largely of myelinated axons.
166
Dorsal horns
The two dorsal arms of the spinal gray matter.
167
Meninges
The three protective membranes that cover the brain and spinal cord (singular meninx).
168
Dura mater
The tough outer meninx.
169
Arachnoid membrane
The meninx that is located between the dura mater and the pia mater and has the appearance of a gauzelike spiderweb.
170
Subarachnoid space
The space beneath the arachnoid membrane, which contains many large blood vessels and cerebrospinal fluid.
171
Pia mater
The delicate, innermost meninx.
172
Cerebrospinal fluid (CSF)
The fluid that fills the subarachnoid space, the central canal, and the cerebral ventricles.
173
Central canal
The small cerebrospinal fluid-filled channel that runs the length of the spinal cord.
174
Cerebral ventricles
The four cerebrospinal fluid-filled internal chambers of the brain: the two lateral ventricles, the third ventricle, and the fourth ventricle.
175
Choroid plexuses
The networks of capillaries that protrude into the ventricles from the pia mater and produce cerebrospinal fluid.
176
Blood–brain barrier
The networks of capillaries that protrude into the ventricles from the pia mater and produce cerebrospinal fluid.
177
Ventral horns
The two ventral arms of the spinal gray matter.
178
Dorsal root ganglia
Structures just outside the spinal cord that are composed of the cell bodies of dorsal root axons.
179
Brain stem
The part of the brain on which the cerebral hemispheres rest; in general, it regulates reflex activities that are critical for survival (e.g., heart rate and respiration).
180
Myelencephalon (medulla)
The most posterior of the five major divisions of the brain; the medulla.
181
Metencephalon
One of the five major divisions of the brain; it includes the pons and cerebellum.
182
Pons
The metencephalic structure that creates a bulge on the ventral surface of the brain stem.
183
Cerebellum
A metencephalic structure that is thought to participate in the storage of memories of learned sensorimotor skills.
184
Mesencephalon
One of the five major divisions of the brain; it is composed of the tectum and tegmentum.
185
Inferior colliculi
The structures of the tectum that receive auditory input from the superior olives.
186
Superior colliculi
Two of the four nuclei that compose the tectum; they receive major visual input.
187
Tegmentum
The ventral division of the mesencephalon; it includes part of the reticular formation, substantia nigra, and red nucleus.
188
Periaqueductal gray
The gray matter around the cerebral aqueduct, which contains opiate receptors and activates a descending analgesia circuit.
189
Cerebral aqueduct
A narrow channel that connects the third and fourth ventricles.
190
Substantia nigra
The midbrain nucleus whose neurons project via the nigrostriatal pathway to the striatum of the basal ganglia; it is part of the mesotelencephalic dopamine system.
191
Red nucleus
A structure of the sensorimotor system that is located in the tegmentum of the mesencephalon.
192
Diencephalon
One of the five major divisions of the brain; it is composed of the thalamus and hypothalamus.
193
Thalamus
The large two-lobed diencephalic structure that constitutes the anterior end of the brain stem; many of its nuclei are sensory relay nuclei that project to the cortex.
194
Massa intermedia
The neural structure located in the third ventricle that connects the two lobes of the thalamus.
195
Sensory relay nuclei
Those nuclei of the thalamus whose main function is to relay sensory signals to the appropriate areas of cortex.
196
Lateral geniculate nuclei
The six-layered thalamic structures that receive input from the retinas and transmit their output to the primary visual cortex.
197
Medial geniculate nuclei
The auditory thalamic nuclei that receive input from the inferior colliculi and project to primary auditory cortex.
198
Ventral posterior nuclei
A thalamic relay nucleus in both the somatosensory and gustatory systems.
199
Hypothalamus
The diencephalic structure that sits just below the anterior portion of the thalamus.
200
Pituitary gland
The gland that dangles from, and is controlled by, the hypothalamus.
201
Optic chiasm
The X-shaped structure on the inferior surface of the diencephalon; the point where the optic nerves decussate.
202
Decussate
To cross over to the other side of the brain.
203
Contralateral
Projecting from one side of the body to the other.
204
Ipsilateral
On the same side of the body.
205
Mammillary bodies
The pair of spherical nuclei that are located on the inferior surface of the hypothalamus.
206
Telencephalon
The most superior of the brain’s five major divisions.
207
Cerebral cortex
The layer of neural tissue covering the cerebral hemispheres of humans and other mammals.
208
Neurons
Cells of the nervous system that are specialized for the reception, conduction, and transmission of electrochemical signals.
209
Multipolar neuron
A neuron with more than two processes extending from its cell body.
210
Unipolar neuron
A neuron with one process extending from its cell body.
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Bipolar neuron
A neuron with two processes extending from its cell body.
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Interneurons
Neurons with short axons or no axons at all, whose function is to integrate neural activity within a single brain structure.
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Nuclei
The DNA-containing structures of cells; also, clusters of neuronal cell bodies in the central nervous system (singular nucleus).
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Ganglia
Clusters of neuronal cell bodies in the peripheral nervous system (singular ganglion).
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Tracts
Bundles of axons in the central nervous system.
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Nerves
Bundles of axons in the peripheral nervous system.
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Fissures
The large furrows in a convoluted cortex.
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Sulci
Small furrows in a convoluted cortex.
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Gyri
The cortical ridges that are located between fissures or sulci.
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Longitudinal fissure
The large fissure that separates the two cerebral hemispheres.
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Cerebral commissures
Tracts that connect the left and right cerebral hemispheres.
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Corpus callosum
The largest cerebral commissure.
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Central fissure
The large fissure that separates the frontal lobe from the parietal lobe.
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Lateral fissure
The large fissure that separates the temporal lobe from the frontal lobe.
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Frontal lobe
The most anterior of the four cerebral lobes.
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Parietal lobe
One of the four cerebral lobes; it is located just posterior to the central fissure.
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Temporal lobe
One of the four major cerebral lobes; it lies adjacent to the temples and contains the hippocampus and amygdala.
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Occipital lobe
The most posterior of the four cerebral lobes; its function is primarily visual.
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Precentral gyri
The gyrus located just anterior to the central fissure; its function is primarily motor.
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Postcentral gyri
The gyrus located just posterior to the central fissure; its function is primarily somatosensory.
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Superior temporal gyri
The plural of superior temporal gyrus.
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Neocortex
Six-layered cerebral cortex of relatively recent evolution; it constitutes 90 percent of human cerebral cortex.
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Pyramidal cells
Large multipolar cortical neurons with a pyramid-shaped cell body, an apical dendrite, and a very long axon.
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Stellate cells
Small star-shaped cortical interneurons.
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Columnar organization
The functional organization of the neocortex in vertical columns; the cells in each column form a mini-circuit that performs a single function.
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Hippocampus
A structure of the medial temporal lobes that plays a role in various forms of memory.
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Limbic system
A collection of interconnected nuclei and tracts that ring the thalamus.
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Amygdala
A structure in the anterior temporal lobe, just anterior to the hippocampus; plays a role in emotion.
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Cingulate cortex
The cortex of the cingulate gyri, which are located on the medial surfaces of the frontal lobes.
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Cingulate gyrus
Large gyri located on the medial surfaces of the frontal lobes, just superior to the corpus callosum.
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Fornix
The major tract of the limbic system; it connects the hippocampus with the septum and mammillary bodies.
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Septum
A midline nucleus of the limbic system, located near the anterior tip of the cingulate cortex.
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Basal ganglia
A collection of subcortical nuclei (e.g., striatum and globus pallidus).
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Caudate
The tail-like structure that is part of the striatum.
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Putamen
A structure that is joined to the caudate by a series of fiber bridges; together the putamen and caudate compose the striatum.
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Striatum
A structure of the basal ganglia that is the terminal of the dopaminergic nigrostriatal pathway.
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Globus pallidus
A structure of the basal ganglia that is located between the putamen and thalamus.
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Blood–brain barrier
The mechanism that impedes the passage of toxic substances from the blood into the brain.
