Week 9

Question 1

What are they hemispheres, lobes, and poles of the brain

Answer 1

Hemispheres- left and right
Four lobes- frontal, parietal, occipital, temporal
Three poles- temporal, frontal, occipital

Question 2

3 major fissures or Sulci

Answer 2

interhemispheric, central, lateral (sylvian)

Question 3

Sulcus/Sulci

Answer 3

A shallow cleft (groove) in the cortex
-central sulcus, pre-central sulcus, post-central sulcus

Question 4

Gyrus/Gyri

Answer 4

A ridge (bump) in the cortex
-pre-central gyrus (primary motor cortex), post-central gyrus (primary sensory cortex)

Question 5

Primary Motor cortex (m1)

Answer 5

Precentral gyrus
-sends efferent motor signal to the spinal motor neuron pool via cortical spinal tract (upper motor neurons)

Question 6

Pre motor cortex (PMC)

Answer 6

Anterior to precentral gyrus
-receives sensory info from parietal cortex, motor info from basil ganglia and cerebellum, and send signal to M1
-involved in generation or motor command signal

Question 7

Primary somatosensory cortex (S1)

Answer 7

Postcentral gyrus
-receives tactile, proprioceptive, and kinesthetic info from the periphery (via thalamus)

Question 8

Primary visual cortex (v1)

Answer 8

Occipital pole
-receives visual info from eyes (via thalamus)

Question 9

Primary auditory cortex (A1)

Answer 9

Superior temporal gyrus
-receives sound info from ears (via thalamus)

Question 10

Parietal cortex

Answer 10

Integration of sensory info (visual, tactile, proprioceptive, and auditory) for attention, perception, and action
-damage leads to acquired disorders of attention, visual-motor control, body and spatial awareness

Question 11

Lateral descending pathways

Answer 11

Serve distal musculature of the hands and feet-involved in fine motor control

Question 12

Medial descending pathways

Answer 12

Serve proximal musculature of the neck, trunk, shoulders, and hips
-largely involved in controlling gross movements, balance, and gait

Question 13

Lesion method

Answer 13

If brain area x is involved in motor performance, then damage to x will lead to movement impairment. The nature of the movement impairment may reveal that brain areas role in performance

Question 14

Decorticate rigidity

Answer 14

Observed when pyramidal tracts are interrupted but extrapyramidal tracts are left intact (de-cortex- input from the cortex is disrupted)
-arms adducted, elbows, wrists, and fingers flexed, legs extended, internally rotated

Question 15

Decerebrate rigidity (worse)

Answer 15

Observed when both pyramidal and extrapyramidal tracts are disrupted
-arms extended with wrists rotated, legs extended, with fee internally rotated

Question 16

Activation method

Answer 16

If brain area x is involved in movement performance, the area x will be more active when people perform a movement task than when they perform some other task

Question 17

Stimulation method

Answer 17

Stimulate a particular region of the cortex by applying a (low-voltage) electrical signal and observe the resulting movement

Question 18

Transcranial magnetic stimulation (TMS)

Answer 18

A method for stimulating a specific brain area in healthy research participants

Question 19

What are the 3 aspects of voluntary movement

Answer 19

1. Locate target using vision- parietal cortex sends location info to premotor and motor cortex
2. Reach- is moving the hand a certain distance and direction (distance and direction are directed by premotor and motor cortex)
3. Grasp

Question 20

Visual Form Agnosia

Answer 20

An inability to use vision to determine shape

Question 21

Optic Ataxia

Answer 21

An inability to use vision to determine location and size for reaching and grasping