Lecture Notes on Visual Motion and Neuroanatomy

Key Points and Concepts

Precision Throwing: Unique to humans, unlike any other animal.
- Importance of visual motion in understanding environment and interactions.
Stop Motion: Difficulty in discerning motion and expressions.
- Importance of small details in facial expressions and lip reading.
Micro Expressions: Subtle facial cues that convey emotions quickly.
Motion Detection: Critical for survival (e.g., avoiding predators, navigating traffic).

Speculative question: Is motion important enough to have specialized brain machinery?
- Hard to live without seeing motion (e.g., crossing streets, hunting).
- Example of a woman lacking motion perception to be discussed later.

Consideration of how to write code to detect motion in videos can provide insights into brain functions.
Importance of understanding ecological and computational needs for motion perception.

Neuroanatomy Basics: Preparing for a human brain dissection session.
Introduction to Brain Anatomy
- Human brain: ~100 billion neurons (10^11)
  - High energy efficiency: 20 watts vs. IBM's Watson at 20,000 watts.

Neuron Anatomy:
- Cell body, nucleus, axon, and dendrites.
- Myelin sheath for faster signal conduction.
Synapses: Thousands per neuron, crucial for brain communication.

Brain Stem: Basic life functions (breathing, consciousness, temperature regulation).
- Primitive, essential for life.
Cerebellum: Involved in motor coordination and possibly cognition.
Subcortical Regions: Including thalamus, hippocampus, and amygdala.
- Thalamus: Central relay station for sensory information.
  - Involved in advanced cognitive functions beyond just relaying information.
- Hippocampus: Critical for episodic memory and navigation.
  - Case of HM and Lonnie Sue Johnson discussed.
- Amygdala: Emotion processing, especially fear.
  - Case of patient SM who cannot experience fear.
White Matter: Axonal connections forming 45% of the brain, important for connectivity.
- Connective 'fingerprints' that indicate brain function.

Cortex Structure: A folded outer layer covering the brain's surface.
Primary Sensory Regions: Visual, auditory, somatosensory, gustatory areas that map sensory inputs.
- Retinotopy: Mapping of visual space in visual cortex.
  - Examples: deoxyglucose experiments, fMRI studies showing maps.
- Touch and auditory maps in somatosensory and auditory cortex.
Maps in Cortex:
- Visual maps in V1 (primary visual cortex).
- Somatosensory maps showing different body areas.
- Auditory maps showing frequency sensitivity.

Defining cortical areas based on function, connectivity, and physical structure.
- Example: Visual Area MT (middle temporal area).
  - Direction-selective neurons crucial for motion detection.
  - Experiments demonstrating systematic direction mapping.
  - Human studies using fMRI to identify motion-sensitive regions.