Perception
We perceive with our BRAIN!
Sensation vs. Perception
• Sensation:
• Perception:
• Our experience is important to perception
– Turnbull (1963)
– phonemes
Vision is the dominant sense
• Has the largest amount of neural
substrate
• Vision trumps other senses
– University of Bordeaux study
– McGurk Effect
The Neuroscience of the
Visual Pathway
1.
2.
3.
4.
The Retina
Optic Nerve --> Central Pathways
Primary Visual Cortex
Association Areas
The Retina
• Photoreceptors: Rods and Cones
• Bipolar Cells
• Ganglion cells
• --> To optic nerve
Central Pathways
• Majority of optic nerve transmits through
Lateral Geniculate Nucleus (thalamus)
V1: The Primary Visual Cortex
• Processes information for features such
as color, form, motion
Association Areas
• The “What” pathway: Through
occipitaltemporal visual stream
• The “Where” pathway: Through
occipitalparietal visual stream
The What/Where Pathway
Distinction: Case Studies
• Blindsight
• Prosopagnosia
Processing: Top Down vs.
Bottom Up
• Top Down:
• Bottom Up:
The Complexity of Pattern Recognition
• Pattern Recognition:
• Visual properties alone do not convey
meaning
• Long Term Memory very involved here
Pattern Recognition: Template
Theory
• Requires direct match between sensory
experience and template in memory
• Problems:
Pattern Recognition: Feature
Analysis Theory
• Analysis of elements of stimulus
• Synthesis puts the features together
into a coherent whole
The Importance of Context
• Context aids recognition in providing
expectations about incoming patterns
• May activate patterns in LTM prior to
sensory experience of pattern
• Final recognition is guided by LTM
Gestalt Prinicples of
Organization
Connection of Vision to
Emotion
• Capgras delusion
The Special Case of Smell:
The Proust Effect
• Smell does not go through thalamus
• Smell is closely related to memory and
emotion