Lectures

Question 1

• Neocortex: six layers (I–VI)

Answer 1

• Layers II–III: cortical-to-cortical output
  
  • Layer IV: primary cortical input (receives thalamic projections)
  • Layers V–VI: subcortical outputs (thalamus, brainstem, spinal cord)

Question 2

1. Medulla oblongata

Answer 2

• Vital autonomic centers (cardio-respiratory)
  
  • Entry/exit point for most cranial nerves

Question 3

2. Pons (“bridge”)

Answer 3

• Connects cerebellum ⇄ cerebrum
  
  • Houses superior olivary nucleus (auditory processing)
  • Contains part of the reticular formation: source of norepinephrine (locus coeruleus) and serotonin (raphe nuclei)

Question 4

3. Midbrain

Answer 4

• Tectum: superior colliculus (visual orienting), inferior colliculus (auditory relay)
  
  • Tegmentum: ventral tegmental area (dopamine release)
  • Pineal gland (circadian hormone regulation)

Question 5

Cerebellum: “Little Brain”

Answer 5

• Highly foliated cortex with dense Purkinje cell layer
• Receives an “efference copy” of cortical motor commands + proprioceptive feedback
• Computes error between intended vs. actual movement → sends corrective signals back to motor cortex → fine-tunes coordination, balance

Question 6

Diencephalon & Basal Ganglia

Answer 6

• Hypothalamus: homeostasis (hunger, thirst, temperature), hormone regulation, autonomic control
• Thalamus: relay station for nearly all sensory/motor pathways to cortex
• Basal ganglia (caudate, putamen, globus pallidus):
  
  • Role in motor control, habit learning, reward
  • Key node in dopaminergic pathways (e.g. VTA → nucleus accumbens)
  • Clinical application: deep brain stimulation in subthalamic nucleus alleviates Parkinsonian tremor

Question 7

1. Frontal Cortex

Answer 7

• Dorsolateral PFC: working memory, cognitive control, planning.
  
  • Ventromedial/orbitofrontal: value‐based decision‐making, emotion regulation; damage (e.g. Phineas Gage) → impulsivity, poor social judgment.
  • Anterior cingulate: conflict monitoring, error detection, motivational integration.

Question 8

2. Parietal Cortex

Answer 8

• Posterior parietal: spatial attention, coordinate transforms, sensorimotor integration; encodes external space and internal state (e.g. hunger × reach).

Question 9

3. Temporal Cortex

Answer 9

• Ventral stream: object, face, and complex pattern recognition.
  
  • Medial temporal lobe (hippocampus): episodic memory formation.

Question 10

4. Cerebellum & Basal Ganglia (briefly recapped)

Answer 10

• Cerebellum: error‐correction in motor commands via efference copy vs. proprioceptive feedback.
  
  • Basal ganglia: action selection, habit learning, dopaminergic reward signals; clinical relevance (e.g. Parkinson’s DBS).