L15 - Cerebral Hemispheres

Question 1

What makes up the CNS and PNS?

Answer 1

CNS:
- Brain (encephalon)
- Spinal cord

PNS:
- Cranial nerves (connect to brain, innervate head)
- Spinal nerves (connected to spinal cord, innervate everything else)
- Ganglia (groups of neurons in PNS)

Question 2

Characteristics of the nervous system?

Answer 2

(think CPR)
1. Collect (external and internal info from diff parts of the body)
2. Process (visual/sensory info, etc)
3. Respond (controls/adjusts activity of other body systems)

• Fast acting
• Small in terms of body weight (3%)

Question 3

Grey and white matter

Answer 3

Grey: contains neuron cell bodies, dentrites, synapses
White: Myelinated axons

Question 4

The brain (encephalon) + spine

Answer 4

1. Cerebrum (telencephalon) = left and right hemispheres, for high cognitive, complex thoughts movements… ALSO basal nuclei, controls wanted/unwanted movement.
2. Diencephalon = thalamus (gatekeeper), hypothalamus (homeostasis, endocrine)
3. Brain stem (life saver)
4. Cerebellum (balance, movement)
5. Spinal cord (processing, stretch)

Question 5

Development of the rostral neural tube (part of embryo that becomes the brain/spine)

Answer 5

• neural tube.
• neural tube walls become parts of CNS
• inside of the tube becomes spaces in the CNS containing cerebrospinal fluid
• the front part (rostral) of the tube grows and changes most.
• insular cortex develops last

Question 6

Five lobes

Answer 6

1. Frontal (Motor output - action)
2. Parietal (Sensory input - perception)
3. Temporal (Sensory input - perception)
4. Occipital (Sensory input - perception)
5. Limbic (Learning and memory)

THINK POT is SENSORY (perception)

Question 7

Insular cortex

Answer 7

• Deep inside lateral sulcus
• for gustation (taste)

Question 8

Voluntary motor control

Answer 8

0.5. Thalamus (Sensory input goes in)

1. Primary sensory cortex (post central gyrus, map)
2. Secondary sensory cortex
3. Higher order association cortex

-LIMBIC LOOP happens between these, important memories-

4. Prefrontal cortex (also higher order)
5. Supplementary motor cortex + pre motor cortex
6. Primary motor cortex (pre central gyrus, map)
7. Pyramidal tracts and brainstem (Somatomotor output)

(Everything but primary motor and sensory cortex for planning)

Question 9

Cerebral cortices hierachy

Answer 9

1. Primary - RECEIPT (simple info processing - pre-central, post central-gyrus)
2. Secondary 0 INTERPRETATION (near primary, more specific of one sensory or motor thing)
3. Tertiary - INTEGRATION (processing complex info, e.g. patterns, emotions, etc)

Question 10

Pyramidal tract (Corticospinal tract - voluntary movements of body)

Answer 10

1. Primary motor cortex (Pre-central gyrus)
2. Internal capsule
3. Brain stem (midbrain, pons, medulla)
4. Spinal cord

• BUT the corticobulbar tract is same but branches off at brain stem to the cranial nerve (controls voluntary movements of head)

Question 11

Extrapyramidal tract (INVOLUNTARY movements like muscle tone, muscle tone)

Answer 11

1. Starts in VARIOUS areas, including cerebellum, basal ganglia, parts of motor cortex.
2. Brain stem
3. Spinal cord