Lecture Notes on Motion Perception and Neuroanatomy

Key Points on Motion Perception

Human Unique Ability: Precision throwing is a uniquely human ability despite many animals sharing motion perception.
Importance of Motion: Motion is critical for survival, both for predator avoidance and prey catching.
Lip Reading: Poor audio quality can lead to reliance on lip reading, which is challenging due to the subtleties of facial expressions.
Facial Expressions: Emotions are expressed through nuanced micro-expressions that last only a brief moment. Humans are sensitive to these fleeting expressions, aiding social interactions.

Brain Machinery for Motion: There might be specialized brain regions for processing motion due to its ecological importance.
Living in a Strobe World: Imagining a life where motion perception is compromised raises questions about survival and navigation, particularly crossing streets safely.

Neurons: Human brain contains around 100 billion neurons; each neuron has an axon and dendrites, with myelin sheaths for faster signal transmission.
Brain Efficiency: The brain operates on approximately 20 watts, showcasing its energy efficiency compared to computers.

Cortex: The outer covering of the brain responsible for higher-order functions.
Brain Stem: Connects the spinal cord to the brain, controlling essential survival functions like breathing and temperature regulation.
Cerebellum: Involved in motor coordination; its role in cognitive functions is still debated.
Limbic System: Involved in emotion and memory processing.
White Matter: Composed of axons that connect different brain regions and plays a crucial role in communication within the brain.

Function: Acts as a relay station for sensory information before it reaches the cortex. Most sensory pathways, except olfactory, pass through the thalamus.
Higher Functions: Recent evidence suggests the thalamus is also involved in higher cognitive functions.

Hippocampus: Critical for episodic memory and navigation. Famous case study of patient HM highlights its importance in memory formation.
Amygdala: Involved in emotion processing, particularly fear. A patient with amygdala damage (patient SM) shows inability to recognize fear.

Receptive Fields: Neurons respond to specific stimuli in a defined area; adjacent neurons tend to have similar receptive fields reflecting a spatial map in the cortex.
Functional Specialization: Different areas of the cortex specialize in different sensory modalities (e.g. visual, auditory, somatosensory).

Visual Area MT: Specialized for motion processing; neurons here are direction selective. Evidence includes cell recordings in monkeys and functional imaging in humans showing response patterns to moving stimuli.
Connectivity Fingerprints: Unique connections of cortical areas help define their function; distinct patterns of connectivity distinguish different cortical regions.
Cytoarchitecture: Some areas, like MT, have distinct cellular structures, signifying their specialized functions.

Importance of motion perception in daily life and brain function.
Key neuroanatomical structures relevant to sensory processing and cognitive functions.
The relationship between brain connectivity, structure, and function in understanding motion and perception.