Cerebral Cortex Part II

Question 1

Cerebral White Matter

Answer 1

Commissural fibers, association fibers, projection fibers

Question 2

Commissural fibers

Answer 2

connect hemispheres. Corpus Callosum

Question 3

Association Fibers

Answer 3

connect different parts of the same hemisphere. Ex. Wernickes and Brocas

Question 4

Projection Fibers

Answer 4

Connect cerebral cortex to caudal regions. Sends senory info and motor instructions. In deep white matter they make a compact bundle ( internal capsule)
-corona radiata

Question 5

Corona Radiata

Answer 5

projection fibers. superficial to internal capsule.

fibers fan out and run to and from cerebral cortex.

Question 6

Deep Gray Matter- Basal Ganglia

Answer 6

group of nuclei embedded deep within the cerebral white matter.
Receive input from many cortical areas- start, stop and regulate intensity of voluntary movements. Choose appropriate muscle and inhibit others. Influenced by substantia nigra.
includes: corpus striatum and globus pallidus

Question 7

Deep Gray Matter- Basal Ganglia- Corpus striatum

Answer 7

caudate nucleus- arches over thalamus medial to internal capsule
putamen- lateral to internal capsule

Question 8

Deep Gray Matter- Basal Ganglia- Globus Pallidus

Answer 8

lateral to internal capsule.

Question 9

Dyskinesia

Answer 9

degeneration of basal nuclei. causes motor disorders.

Question 10

Huntington’s Disease

Answer 10

Degeneration of corpus striatum path that inhibits motor activity. Overstimulation occurs causing jerking.

Question 11

Parkinson’s

Answer 11

degeneration of substania nigra that normally sends inhibatory signals to basal ganglia. causes overactive globus pallidus which inhibits motor cortex.
slow jerking and tremors then eventually muscle rigidity.

Question 12

Deep Gray Matter- Basal Forebrain Nuclei

Answer 12

part of cholinergic system-- neuron synthesis and release of abundance of acetylcholine. 
Anterior and dorsal to hypothalamus
arousal
learning
memory
motor control

Question 13

Alzheimer’s

Answer 13

degeneration of areas involved in memory/though (basal forebrain nuclei, hippocampus, parts of cerebral cortex)
Reduction of cholinergic activity

Question 14

Brain Systems- Limbic System

Answer 14

made of:
septal nuclei
cingulate gyrus
denate gyrus
hippocampus
parahippocampal gyrus
amygdala (part)
hypothalamus
anterior thalamic nuclei
mamillary bodies
 linked by fornix and anterior commissure fiber tracts

Question 15

Cingulate Gyrus

Answer 15

enables shift between thoughts and expression through gestures.
Makes pain unpleasant.
Resolves frustration

Question 16

Amygdala (limbic role)

Answer 16

fear. sympathetic response.
recognize menacing facial expressions & direction of gaze
forms memories based on emotions and can cause you to re-experience them when memories are brought up.(PTSD)

Question 17

Hippocampal Formation

Answer 17

hippocampus + parahippocampal gyrus
encodes, consolidates and later retrieves memories.
Receives info, processes and returns to cerebral cortex to be stored long term.

Question 18

Reticular Formation (see midbrain)

Answer 18

connects widely separated regions of the thalamus, cerebellum, spinal cord and cerebrum
allow functioning as a whole.
sleep arousal- defective = narcolepsy
regulate automatic processes