Sensation and Perception: Key Concepts and Theories

Sensation

Physical processing of environmental stimuli by sense organs.

Perception

Psychological process of interpreting sensory information.

Psychophysics

Study relating physical stimulus characteristics to perception.

Absolute threshold

Smallest stimulation needed for detection 50% of the time.

Just noticeable difference

Minimum difference needed to detect change 50% of the time.

Top down processing

Perception influenced by expectations and prior knowledge.

Bottom up processing

Constructing perception from individual sensory bits.

Signal detection theory

Response depends on sensitivity and decision criteria.

Sensory adaptation

Diminished sensitivity due to constant stimuli.

Selective attention

Focusing on one specific task or event.

Inattentional blindness

Failure to perceive objects outside focus of attention.

Change blindness

Failure to notice changes in visual details.

Vision

Light processed to create an image on the retina.

Nearsightedness

Light focused in front of the retina.

Farsightedness

Light focused beyond the retina's surface.

Photoreceptors

Cells transforming light into neural signals.

Ganglion cells

Gather information from photoreceptors for processing.

Dorsal pathway

Pathway for processing 'where' visual information.

Ventral pathway

Pathway for processing 'what' visual information.

Visual agnosia

Inability to recognize objects visually.

Prosopagnosia

Inability to recognize familiar faces.

Trichromatic theory

Three cones sensitive to different light wavelengths.

Opponent process theory

Perception of color in opposing pairs.

Monocular depth cues

Depth perception using one eye.

Binocular depth cues

Depth perception using both eyes' perspectives.

Multimodal perception

Concurrent stimulation affects perception across modalities.

McGurk effect

Combining auditory and visual information for speech.

Synesthesia

Exceptional sensory experiences triggered by cognition.