L3 - Brainstem and Cerebellum Flashcards Preview

PSYC1020 - Introduction to Psychology - Minds, Brains and Behaviour > L3 - Brainstem and Cerebellum > Flashcards

Flashcards in L3 - Brainstem and Cerebellum Deck (8):
1

Nervous System:

Central Nervous System:

  • Brain and spinal cord

Peripheral nervous system:

  • Somatic (voluntary motor and sensory control)
  • Autonomic (involuntary mechanisms e.g. HR, RR, stress etc.)

Autonomic Nervous System:

  • Sympathetic ("fight-or-flight") +
  • Parasympathetic ("rest & digest")
  • Heart-rate, respiration, sweating
  • Stress, arousal

2

Brainstem:

= ANS functions + relay system

  • Medulla
    • ANS functions (HR, RR, vasomotor) + reflex centres (cough, sneeze, swallow, vomit)
    • Controls heart-rate, respiration, regulation of blood pressure, body temperature

  • Pons
    • Relay between Cerebral cortex → cerebellum
    • Some nerves to the face for some facial expressions and eye-movements

  • Midbrain

3

Disorders of consciousness (functional MRI is required to distinguish between these):

  • Persistent vegetative state = No conscious awareness due to severe upper brain damage (hemispheres and cortex) but preservation of ANS (brainstem unaffected)

 

  • "Locked-in" syndrome = Full conscious awareness but (normal cognitive function/vision/hearing) but unable to move
    • Amyotrophic lateral sclerosis (ALS) or motor neuron disease = Loss of motor neurons to spinal cord
    • Brain injury = Disconnection of brainstem → spinal cord

4

Cerebellum:

  • Hindbrain (latin for little brain)
  • Sense of balance, coordination of complex movement and motor learning (fine adjustment of movement based on feedback)

5

“Motor Programs” for movement:

Movements planned & programmed in brain before initiation, ike a computer program (theory from 1960’s)

  • Brain creates program immediately before movement

OR

  • Brain retrieves program for learnt skilled actions (e.g. tennis, signature)

6

Feedback programs:

Brain computes difference of planned actions compared to actual actions performed

  • Prediction of expected sensory feedback with actual feedback
  • Learning motor skill = ↓ Prediction error (mismatches)

7

Sense of agency:

Feedback matches predictions from planned actions

  • Brain links sensory events and self-actions to infer causality
  • We can sense that our personal actions cause an event (e.g. can't tickle ourselves)

8

Summary of evolution:

  1. Brainstem + Cerebellum = ANS + Movement coordination
  2. Limbic system = Fear/threat learning (amygdala) + Memory & environmental navigation (hippocampus)
  3. Cerebral hemispheres (cerebral cortex) = Planning, reasoning & problem solving + Language (temporal) + Visual perception (occipital/parietal lobe) + Motor functions (motor cortex)