Sensory and Perception

Sensation

The process of detecting physical stimuli (light, sound, pressure) from the environment.

Perception

The interpretation and organization of sensory information into meaningful experiences.

Transduction

The conversion of physical stimuli into neural signals by sensory receptors.

Absolute Threshold

The minimum intensity of a stimulus needed for detection 50% of the time.

Difference Threshold (Just Noticeable Difference, JND)

The smallest detectable change between two stimuli.

Bottom-Up Processing

Perception driven by raw sensory input.

Top-Down Processing

Perception influenced by expectations, experience, and cognition.

Vision Pathway

Path of visual processing from the retina to the brain.

Auditory Pathway

Path of auditory processing from the ear to the brain.

Dorsal Stream

'Where' pathway responsible for motion, depth, and spatial location.

Ventral Stream

'What' pathway responsible for object recognition and color.

Cortical Blindness

Loss of conscious vision due to damage to the Primary Visual Cortex (V1).

Optic Ataxia

Difficulty using vision for guiding actions resulting from Dorsal Stream damage.

Visual Agnosia

Difficulty recognizing objects resulting from Ventral Stream damage.

Prosopagnosia

Deficits in recognizing faces due to damage to the Ventral Stream.

Auditory Agnosia

Difficulty recognizing sounds due to damage to Heschl's Gyrus.

Mechanoreceptors

Sensory receptors in the skin that detect pressure, heat, and pain.

Photoreceptors

Cells in the retina (rods and cones) that transduce light into electrical signals.

Lateral Geniculate Nucleus (LGN)

Thalamic relay center for visual signals.

Medial Geniculate Nucleus (MGN)

Thalamic relay center for auditory signals.

Heschl’s Gyrus

Part of the primary auditory cortex involved in processing complex sounds.

Chemical Signals

Detected by taste buds and olfactory receptors, processed for taste and smell.

Primary Sensory Cortex

Area in the brain where incoming sensory signals are processed.

Primary Visual Cortex (V1)

Processes basic visual features like edges and movement.

Primary Auditory Cortex (A1)

Processes tone, pitch, and speech in the auditory system.