Unit 2: Neuroanatomy Flashcards
1
Q
What is most characteristic of the “Teen Brain”?
A
Risk taking, trouble controlling impulses, trouble judging risks and rewards, emotional intensity/instability, adaptability, plasticity, vulnerability.
2
Q
What is an underlying cause of teenage behavior?
A
Lack of inhibitory control caused by the mismatch in the timing of two developments of brain networks; that of the prefrontal cortex, which is still developing in teens, and the limbic system which is developed and intensifies at puberty.
3
Q
What is the limbic system involved with?
A
Reward system, “emotional brain”
4
Q
What is the frontal lobe involved with?
A
Executive functions: reasoning, judgement, planning, inhibition, impulse control
5
Q
What is happening to the frontal lobe during the teen years?
A
It is engaged in the process of first growing and then pruning.
6
Q
What is pruning?
A
The elimination of “bad” or unused connections and strengthening of “good” and used ones.
7
Q
Are teen brains meant to be mismatched?
A
Evolution has designed the teen brain to be different than a child or adult brain. Vulnerability, but also plasticity, which leads to big strides in cognition.
8
Q
Where does a peak in gray matter (neurons) occur first and last?
A
Gray matter peaks earliest in the sensorimotor areas and latest in the prefrontal cortex.
9
Q
What is a primary cortex area responsible for?
A
Straight forward function
10
Q
What is an association area for?
A
They are places of connection that integrate info from different areas.
11
Q
What are the convolutions for on our brains?
A
More surface area!
12
Q
What makes up the CNS?
A
Brain and spinal cord
13
Q
What makes up the PNS?
A
Somatic NS and Autonomic NS (both sensory and motor)
14
Q
Divisions of ANS?
A
Sympathetic and Parasympathetic
15
Q
What are the most notable changes in the development of the brain?
A
- Division into forebrain, midbrain and hindbrain.
2. Increase in convolutions.
16
Q
The prenatal events of divisoin and convolution are key in the development of disorders such as
A
Schizophrenia and autism.
17
Q
What are the three main components of brain protection?
A
Skull, meninges, blood supply and CSF + ventricular system.
18
Q
What is the most protected organ?
A
The brain
19
Q
What is the brain mainly composed of?
A
Neurons, glia and water
20
Q
How much does the brain weigh?
A
About 3lbs.
21
Q
How many layers make up the meninges?
A
Three membranes and a space.
22
Q
What are the layers of the meninges?
A
- Dura Mater
- Arachnoid Membrane
- Subarachnoid Space
- Pia Mater
23
Q
What is the arachnoid membrane? Where is it?
A
Spongy layer underneath the dura mater and above the subarachnoid space.
24
Q
Disorders of the meninges include
A
meningitis and meningioma
25
Meningitis
Infection and inflammation of the meninges
26
Meningioma
Tumor of the meninges, potentially easily removable
27
What is the purpose of the meninges?
Membranes under skull that cover and protect the brain and spinal cord surface
28
How does the blood protect the brain?
1. Takes away CO2 and waste; brings oxygen and nutrients.
| 2. Blood Brain Barrier (BBB)
29
What percent of the body's blood does the brain get?
20% of the body's blood
30
What is the blood brain barrier (BBB)?
Between capillary wall, astrocytes, and neural tissue; protects substances in the bloodstream from entering the brain tissue.
31
What is a brain disorder/injury associated with blood supply?
Strokes
32
What is a stroke?
When an area of the brain is temporarily blocked from getting blood flow and the area may die.
33
What are the main 2 causes of strokes?
Obstruction (clots) - 80%
| Hemorrhages 20%
34
What kind of drugs are used when there are obstructions in the brain's blood supply?
Statins- break down debris
35
Where does most of the brain's blood supply come from?
Cerebral arteries
36
Where are the major cerebral arteries serving the brain?
Top, middle, and bottom of brain
37
How does CSF and the ventricular system protect the brain?
1. By providing a cushion and shock absorber
| 2. Floats the brain, reducing essential weight
38
What is an important function of the ventricular system?
Production, flow and reabsorption of the CSF
39
Where are the brain's ventricles?
2 large ventricles on either side
1 in the middle
another smaller one in the middle
40
How does the CSF flow?
ventricles -> subarachnoid space -> carries away waste
41
What is hydrocephalus?
"Water on the head." Occurs in Utero. Caused by a blockage in ventricles and CSF can't flow or be reabsorbed, putting pressure on the brain and leading to damage.
42
How is hydrocephalus diagnosed?
Look at head size and eyes.
43
How is hydrocephalus treated?
Shunts placed to drain CSF
44
Where is a lumbar puncture done?
At L3-L4, BELOW spinal cord. Collect CSF from nerves after spinal cord ends.
45
Where does the spinal cord end?
At about L1
46
What composes the forebrain?
1. Cerebral Cortex
2. Thalamus
3. Hypothalamus
4. Limbic System
5. Basal Ganglia
47
What are the features of the cerebral cortex?
1. Thin (2-3mm, packed with cells), convoluted "bark"
2. Gyri, sulci, fissures
3. Includes primary cortical areas
4. Includes the association cortexes
48
What lobes make up the cerebral cortex?
Frontal, Temporal, Parietal, Occipital
49
What is a lissencephalic brain like?
Big ventricles, almost completely absent convolutions
50
What is the dorsal view of the brain?
from the top
51
What is the ventral view of the brain?
from the bottom
52
What are two association areas of the frontal lobe?
Primary Motor Cortex, Broca's Area
53
What is the role of the primary motor cortex?
voluntary movement
54
What is the motor homunculus?
Representation of the human body based on the importance and PMC tissue allocated to specific body areas.
55
What body parts are very large on the motor homunculus?
Hands and mouth
56
What are other functions of the FL association cortex?
Executive functions and high level cognition: decision making, regulation of emotion, reasoning, planning, thinking
57
What are some disorders of the frontal lobe?
Schizophrenia
| ADHD
58
What is different about the frontal lobe in those with Schizophrenia?
Hyperactivty in frontal lobe
59
What is different about the frontal lobe in those with ADHD?
Key dopamine pathways are not functioning properly.
60
What 2 main areas compose the parietal lobe cortex?
Primary Somatosensory Cortex, Gustation area
61
What is the role of the Primary Somatosensory Cortex?
Sensory info from body - skin: touch, temp, pain, pressure
62
What is gustation?
taste
63
What is the association cortex function in the parietal lobe?
further analyzes and processes info from somatosensory cortex.
has a spatial function: proprioception, where body is in relation to limbs and environment
64
What is a disorder associated with damage to the parietal lobe?
Unilateral Neglect
65
What side of the brain is usually damaged in unilateral neglect?
The right parietal lobe
66
What is unilateral neglect?
Information from left field not connected to consciousness. Individual unaware of one side of their world. Often due to stroke.
67
What are some tell-tale signs of unilateral neglect?
Drawing only one side of a picture, putting makeup on or shaving only half the face.
68
What is the occipital lobe's main component
primary visual cortex (PVC)
69
What is the primary visual cortex responsible for?
simple, minimal visual processing such as lines
70
What are the association cortices in the occipital lobe for?
more complex visual processing by combining the basic features such as color, movement and form.
71
What happens if someone has damage to their PVC?
Blindness
72
What happens if someone has damage to their association areas in the occipital lobe?
can tell basic features of object from sight but cannot identify
73
What is a disorder when someone can see but can not identify or process object?
visual agnosia
74
What primarily composes the temporal lobe?
primary auditory cortex, olfactory cortex, Wernicke's area
75
Where is Wernicke's area?
At the junction of different lobes
76
What is the function of the primary auditory cortex?
Distinguishing pitch, loudness, and frequency of sounds
77
What is olfaction?
Smell
78
What is Wenicke's area responsible for?
Speech Comprehension
79
What occurs if someone has damage to Wernicke's area?
They have difficulty understanding and producing sensible and meaningful speech.
80
What is the association area in the temporal lobe responsible for?
learning and memory, visual recognition especially faces
81
Capgras Syndrome is a ___ syndrome
Capgras Syndrome is a disconnection syndrome
82
What is Capgras Syndrome?
Damage to fibers in association area of temporal lobe involved with facial recognition; leads to one believing that their friends and family are imposters.
83
Why does someone with Capgras Syndrome believe their friends and family are imposters?
They recognize the face but have no emotional response, and conclude that they must not really be that person
84
What kind of disconnection is happening in Capgras Syndrome?
There is a disconnection between the facial recognition area and amygdala in the limbic system.
85
What are some disorders that can involve Capgras Syndrome?
Schizophrenia, AD, brain trauma
86
What happens if someone with Capgras Syndrome looks in the mirror?
1. Could think it is not themselves, and therefore a fake mirror
2. Could see themselves
87
What is the order of the forebrain?
```
Cortex
Limbic System
Basal Ganglia
Thalamus
Hypothalamus
```
88
Where is the thalamus?
2 large lobes at the base and center of forebrain
89
What is the function of the thalamus?
It is a sensory relay station for somatosensory, visual, auditory, and gustatory senses
90
Information from what sense does not go through the thalamus?
Olfactory
91
What does it mean that the thalamus is a relay station?
Sensory information goes through the thalamus on its way to the cortex, and there are reciprocal connections that modulate input.
92
Where is the hypothalamus?
At the base of the forebrain, below the thalamus.
93
What does the hypothalamus do?
1. Controls the "Four Fs": Feeding, Fighting, Fleeing, Fornicating
2. Homeostasis
3. Controls ANS (connects with glands and organs)
4. Controls pituitary gland and endocrine system.
94
What aspects of homeostasis does the hypothalamus regular?
Body temp, glucose levels, etc.
95
What are the two "systems" that include most of their parts in the forebrain?
Limbic System and Basal Ganglia
96
What is the limbic system also called?
The "emotional brain"
97
What makes the limbic system a system?
It is a circuit of interconnected structures that work together
98
What are the functions of the limbic system?
Emotions, motivation, memory (emotional memories)
99
What parts of the brain make up the limbic system?
Hippocampus, Amygdala, Cingulate cortex
100
What is the function of the basal ganglia?
Complex motor control, starting and stopping movements, posture and balance
101
Where does the basal ganglia receive input from?
The basal ganglia receives input from the primary motor cortex and modulates it
102
What are some disorders associated with the basal ganglia?
Parkinson's Disease
Huntington's Chorea
OCD (motor compulsions)
Tourette's syndrome (motor tics)
103
What are some characteristics of Parkinson's Disease?
Tremors, Akinesia (rigidness), gait change
104
Where are the midbrain and hindbrain mostly located?
In the brain stem
105
Where is the midbrain?
Top of brain stem
106
What are the components of the midbrain?
1. Tectum (sensory)
| 2. Tegmentum (motor) -> part of complex motor system
107
Where is the Reticular formation (RAS)?
Part of the midbrain that extends through the brain stem to the rest of the CNS
108
What is the Reticular formation involved in?
arousal, muscle tone
109
What composes the hindbrain?
cerebellum, pons, and medulla
110
What is the function of the cerebellum
Simply: motor coordination and procedural memory
111
What disorder might the cerebellum play a role in?
Autism
112
Where is the pons?
upper brain stem
113
What NT are the pons a source of?
Serotonin and Norepinephrine
114
What is the function of the pons
Bridge to cerebellum and back; involved in arousal and sleep
115
Where is the medulla located?
Lower brain stem
116
What is the function of the medulla?
Maintaining basic life sustaining functions: respiratory rate, heart rate, digestive processes
117
What syndrome is the medulla possibly involved in?
SIDS
118
What is the width of the spinal cord?
Middle finger
119
What is the spinal cord?
Elongated, tubular bundle of nerves protected by the vertebral column
120
What does the spinal cord connect to?
spinal nerves to serve all parts of the body (PNS), as well as the brain
121
What are spinal reflexes?
Reflex pathways that don't require the brain. Pain/sensory info in->motor out
122
What are two spinal reflexes?
Patellar reflex and withdrawal reflex
123
What is the pathway of the patellar reflex?
Tap patellar tendon (sensory in) -> 1 synapse in motor neurons -> muscle on thigh contracts. Is monosynaptic
124
What is different about the withdrawal reflex?
The brain can override (inhibit reflex)
125
What makes up the PNS?
Somatic NS and Autonomic NS
126
What nerves compose the somatic NS?
Spinal nerves and cranial nerves
127
How many pairs of spinal nerves are there?
31; travel together
128
What is the somatic nervous system (big picture/system perspective)
the external link
129
What are the functions of the somatic NS?
Sensory in, motor out
130
What is a disorder of the spinal nerves in the somatic NS?
ALS
131
How many cranial nerves are there? Are they sensory or motor?
There are 12 cranial nerves; some sensory, some motor, some both
132
What are the two branches of the ANS?
sympathetic and parasympathetic
133
When is the sympathetic NS active?
during CATABOLIC (energy using) activities
134
When is the parasympathetic NS active?
during ANABOLIC activities; when restoring things to steady state
135
What is the ANS (big picture/system perspective)
internal link
136
What to the nerves of the ANS innervate?
Organs and glands
137
What are two very similar spinal nerve disorders?
ALS and CTE
138
What is ALS?
An upper and lower motor system disorder
139
What is the focus when it comes to possible causes and treatments?
Antioxidants and glutamate
140
What is CTE?
Chronic Traumatic Encephalopathy. Linked to repeated head trauma (in sports)
141
What are some ways to study the live human brain? (Imaging techniques)
```
CT/CAT
MRI
fMRI
PET
EEG
ERP
```
