EYES & EARS

Pinna

The outer part of the ear that collects sound waves.

Auditory canal

Carries sound inward after it is collected by the pinna.

Tympanic membrane

Also known as the eardrum, it vibrates in response to sound waves.

Hammer (Malleus)

Transmits vibrations from the tympanic membrane.

Anvil (Incus)

Transfers vibrations from the hammer to the stirrup.

Stirrup (Stapes)

Pushes on the oval window to transfer vibrations into the inner ear.

Cochlea

A fluid-filled structure that facilitates the conversion of sound vibrations into neural signals.

Hair cells (Cilia)

Movement triggers transduction of sound in the cochlea.

Auditory nerve

Carries neural signals from the cochlea to the thalamus.

Thalamus (auditory)

Relays auditory information to the auditory cortex.

Auditory cortex

Processes sound information from the auditory nerve.

Cornea

Bends incoming light as the first part of the eye.

Pupil

The opening through which light enters the eye.

Lens

Focuses light onto the retina.

Retina

Contains rods and cones that detect light and facilitate transduction.

Bipolar cells

Relay signals from photoreceptors (rods and cones) to ganglion cells.

Ganglion cells

Their axons form the optic nerve to transmit visual information.

Optic nerve

Carries visual signals from the eye to the thalamus.

Thalamus (visual)

Relays visual information to the visual cortex.

Visual cortex

Processes visual information in the brain.

Absolute threshold

The minimum stimulation needed to detect a stimulus 50% of the time.

Signal detection theory

The theory that detection of a stimulus involves the interaction of signal strength, noise, attention, and expectations.

Subliminal

Stimuli that are below the threshold of conscious awareness.

Priming

The process by which exposure to a stimulus influences a response to a subsequent stimulus.

Difference threshold

The smallest detectable difference between two stimuli, identified 50% of the time.

Weber's law

The principle that the noticeable difference is a constant proportion of the original stimulus.

Sensory adaptation

Diminished sensitivity to a constant stimulus due to prolonged exposure.

Inattentional blindness

Failing to notice a visible object because attention is focused elsewhere.

Change blindness

Failing to notice a change in a visual scene.

Gestalt

The principle that the brain organizes sensations into meaningful wholes.

Figure-ground

The perceptual distinction between an object (figure) and its background.

Depth perception

The ability to see the world in three dimensions and judge distance.

Binocular cues

Depth cues that depend on the use of both eyes.

Monocular cues

Depth cues available to either eye alone.

Perceptual constancy

Perceiving objects as unchanging despite changes in sensory input.

Color constancy

The tendency to perceive the color of an object as constant even under varying lighting.

Gate control theory

The theory that the spinal cord contains a gate that blocks or allows pain signals to pass to the brain.

Wavelength

The distance between successive wave peaks; relates to color in visible light.

Hue

The specific color we perceive.

Intensity

The strength of a stimulus, relates to the brightness of light and the loudness of sound.