Cerebrum

Question 1

main function of the cerebrum

Answer 1

center of consciousness
1. sensory processing
2. motor planning
3. consciousness
4. memory

Question 2

what side of the body do the cerebral hemispheres control

Answer 2

contralateral

Question 3

structure of the cerebrum

Answer 3

telencephalon: cerebral hemispheres, basal nuclei, rhinencephalon
diencephalon: thalamus, hypothalamus

Question 4

gray matter of the cerebrum

Answer 4

cortex and basal nuclei

Question 5

primary type of neuron in the cerebral cortex

Answer 5

pyramidal neurons

Question 6

white matter of the cerebrum

Answer 6

myelinated axons projecting from cells in the gray matter

Question 7

short association axons

Answer 7

connect adjacent gyri (same lobe)

Question 8

long association axons

Answer 8

connect gyri of different lobes (same hemisphere)

Question 9

projection axons

Answer 9

connect cerebrum to thalamus/brainstem

Question 10

commissural axons

Answer 10

connect cerebral hemispheres
- corpus collosum
- rostral commissure

Question 11

neocortex

Answer 11

frontal, parietal, temporal, and occipital lobes

contain all 6 cell layers (molecular, ext granular, ext pyramidal, int granular, int pyramidal, multiform)

Question 12

archicortex

Answer 12

limbic system; hippocampus

contains 3 cell layers

Question 13

paleocortex

Answer 13

piriform lobes, olfactory gyrus

contains 3 cell layers

Question 14

primary cortical areas

Answer 14

six specific areas that intake/output information

1. olfactory region
2. frontal lobes
3. parietal lobes
4. temporal lobes
5. occipital lobes
6. limbic system

Question 15

olfactory region

Answer 15

paired olfactory bulbs, tracts, and piriform lobes
- includes CN I
- has connections to limbic system

processes OLFACTION
(does NOT get processed by thalamus)

Question 16

frontal lobes

Answer 16

primary MOTOR cortex
- origin of corticospinal tract
- somatotopic organization (motor homunculus)

behavior and judgement

Question 17

somatotopic organization

Answer 17

specific cortical areas are associated with specific body surfaces

Question 18

parietal lobes

Answer 18

SOMATOSENSORY (conscious proprioception and nociception)
- receives contralateral sensory information
- somatotopic organization (sensory homunculus)

Question 19

temporal lobes

Answer 19

AUDITORY cortex
- receives fibers from MEDIAL geniculate
- fibers decussate 2x (ends up ipsilateral)

Question 20

occipital lobes

Answer 20

VISUAL cortex
- receives fibers from LATERAL geniculate
- fibers decussate (ends up contralateral)

Question 21

limbic system

Answer 21

brain function, emotion, behavior
- integrates emotional, visceral, and autonomic responses
- 4 Fs - fear, flight, food, reproduction

hippocampus, amygdala, cingulate gyrus, mammillary bodies, septal nuclei

Question 22

association cortexes/areas

Answer 22

areas that are associated with primary cortical areas that integrate the stimuli
- problem solving
- creative thinking
- decision making

recognizes information and forms associations with the senses perceived by the primary areas

Question 23

rhinencephalon

Answer 23

“smell brain” - has an olfactory and non-olfactory portion

olfactory: bulbs, tracts, piriform lobes
non-olfactory: amygdala, septum, hippocampus

Question 24

amygdala

Answer 24

large nucleus located dorsally to the piriform lobe

function: emotion (anxiety, fear, anger)
receives afferents from: cerebral cortex, piriform lobes, thalamus, hypothalamus

Question 25

septal nuclei

Answer 25

located midline and ventral to corpus callosum between the lateral ventricles

function: autonomic functions, behavior, emotion
receives afferents from: olfactory bulb, amygdala

Question 26

hippocampus

Answer 26

loops are rostral/caudal colliculi and thalamus/hypothalamus to attach at mammillary bodies

function: learning and memory; governs aggression and behavior
receives afferents from: neocortex, amygdala, contralateral hippocampus
projects efferents to: hypothalamus, cingulate cortex

Question 27

basal nuclei

Answer 27

subcortical nuclei in each cerebral hemisphere

Question 28

function of basal nuclei

Answer 28

modulate cortical signals for voluntary movement

INHIBITS unwanted movement to release wanted movement

• caudate nuclei
• putamen
• globus pallidus
• claustrum

Question 29

cerebral dysfunction: history

Answer 29

SEIZURES

behavioral changes:
- abnormal urination
- vocalizing
- aggression
- reduced consciousness

Question 30

seizures

Answer 30

clinical manifestations of excessive, synchronous, neuronal firing
- paroxysmal
- involuntary movements
- altered consciousness
- autonomic signs (drooling, urination/defecation)

Question 31

cerebral dysfunction: mentation

Answer 31

normal, obtunded, demented

Question 32

cerebral dysfunction: posture

Answer 32

head turn (NOT tilt) towards side of lesion
decerebrate rigidity (opisthotonus, all 4 limbs)
coma

Question 33

cerebral dysfunction: gait

Answer 33

gait is NORMAL; may express:
compulsive walking/pacing
head pressing
circling toward lesion
contralateral hemiparesis (if corticospinal tract is damaged)

NO paresis or paralysis

Question 34

cerebral dysfunction: cranial nerves

Answer 34

central blindness (contralateral vision loss)
menace deficits
contralateral perceptual deficits

NORMAL PLRs

Question 35

cerebral dysfunction: postural reactions

Answer 35

contralateral deficits on all

Question 36

cerebral dysfunction: spinal reflexes

Answer 36

normal

Question 37

cerebral dysfunction: palpation

Answer 37

apparent pain in cranium/cervical spine due to meninges stretching

Question 38

hemi-inattention syndrome

Answer 38

patient with cerebral disease ignores input from one half of the environment (ignores the side that is contralateral to side with lesion)
- able to perceive stimuli but cannot localize it

Question 39

basal nuclei dysfunction

Answer 39

neurodegeneration of basal nuclei

unable to initiate movement - animal wants to/tries moving forward but is able