Lecture 2.2 (Ch. 4 - Motor Learning Physiology)

How is learning defined physiologically?

• Neuroplastic Modifications of Synaptic Connections

What is considered the simplest form of neuroplastic learning?

• What are the primary mechanisms in how these change?

• Non-Associative Learning (Habituation & Sensitization)

  • Pre-Synaptic - Intensity & Frequency of Synapses

  • Post-Synaptic - Sensitivity & Amount of Receptors

How does Classical Conditioning (Associative) work physiologically?

• At The Same Time, Repeatedly Converging:

  • Weak Stimulus (Learned) + Strong Stimulus (Known)

How does Operant Conditioning (Associative) work physiologically?

• At The Same Time, Repeatedly Converging:

  • Motor Command (Action) + Predicted Reinforcement Signal

How does Procedural Learning work physiologically?

• Using Associative + Non-Associative Data To Create Efficient Feedback Loops → Optimizing Motor Output Patterns

How does Declarative Learning work physiologically?

• A Conscious Version Of Non-Associative Learning (Synaptic Changes)

  • Specifically Emphasized Within Hippocampus

  • Triggered By Pairing Ideas, Not Stimuli

What roughly determines STM vs LTM?

• STM: Signaling Changes

• LTM: Structural Changes

What occurs when explicit memory shifts to implicit movement memory?

• Shift From: Motor Cortex → Prefrontal Cortex (+ Other Such Regions)

  • Requires: Attention, Cognition, & Motivation.

• Note: Eventually Goes Back To Implicit → More Automatic

What are the two categories of Recovery of Function?

• Restorative (Direct) - Repairing Old Structures

• Compensatory (Indirect) - New Structures Form

What are the two categories of Recovery?

• Spontaneous - Early & Natural

  • Ex) Edema, Diaschisis

• Activity-Induced - Trained Overtime

  • Ex) Neurological PT

How does Edema affect brain function?

• Axons Compressed → Diminished Function

How does Diaschisis affect brain function?

• Injured Area → Downstream & Connected Structures Impacted

What are the main differences between CNS vs PNS recovery?

• CNS - Oligodendrocytes

  • Regrowth Inhibited By Environment

• PNS - Schwann Cells

  • Full Neuronal Recovery Achievable

How does the cortical map adapt in CNS vs PNS lesions?

• CNS - Reorganization

  • Ex) After stroke, the hand area of the motor cortex may shift into the face area to compensate.

• PNS - Expansion

  • Ex) In a violinist, the finger representation in the somatosensory cortex expands with practice.

In CNS “recovery,” what is Unmasking?

• Process of Previously Inactive (Silent) Pathways Now Activating

What does recovery look like in MS vs PDD?

• Multiple Sclerosis - CNS Demyelination

  • Episodic - Repair During Remissions.

• Parkinson’s - CNS Basal Ganglia Damage

  • Compensatory - Deficits Masked, Not Fixed.