Module 17 and 18 ap psychology

Vision

The most complex best developed and most important sense for humans - gathers light focuses it, converts it to a neural signal and sends these signals on for further processing

hue

The dimension of color determined by the wavelength of the light

Wavelength

The distance from the peak of one wave to the peak of the next

Intensity

Amount of energy in a wave determined by the amplitude related to perceived brightness

Cornea

Is the transparent tissue where light enters the eye

Iris

a muscle that expands and contracts to change the size of the opening for light

Lens

Focuses the light rays on the retina

Retina

Contains sensory receptors that process visual info and sends it to the brain

Accommodation

The process by which the eyes lens changes shape to help focus near or far objects in the retina

The retina

Light sensitive inner surface of the eye containing receptor rods and cones in addition to layers of other neurons that process visual info

Optic nerve

Carries neural impulses from the eye to the brain

Blind spot

Point where the optic nerve leaves the eye because there are no receptor cells located there

Fovea

Central point in the retina around which the eye cones cluster

Photoreceptors

Light sensitive cells (neurons) in the retina that converts light energy into neural energy

Rods

Photoreceptors that are especially sensitive to dim light but not color

Comes

Photoreceptors that are sensitive to color

Hyperopia

Can’t see nearby objects (farsighted)

Myopia

Can see far (nearsighted)

Astigmatism

Lens defect/out of focus vision

Presbyopia

Farsighted by old age

Opponent process theory

Color perception is controlled by the activity of two opponent systems

Parallel processing

Several aspects of stimulus simultaneously

Recognition

Brain interprets the constructed image based on info from stored images

Retinal processing

Receptor rods + cones → bipolar cells → ganglion cells

Trichromatic theory

Young and vin Helmholtz suggested that the eye must contain 3 receptors that are sensitive to red + blue + green

Perceptual set

A mental predisposition to perceive one thing and not another

Cultural context

Context instilled by culture also alters perception

Extra sensory perception

Perception without sensory input is called ESP

Telepathy

Mind to mind communication

Clairvoyance

Perception of remote events - sensation

Precognition

Seeing future events

Parapsychology

The study of paranormal phenomena including esp and psychokenisis

Feature detectors

nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement.

Sensation

The process of receiving stimuli from the environment through sensory organs

Perception

The interpretation and organization of sensory info allowing us to understand our surroundings

Bottom up processing

Analysis that begins with sensory receptors and builds up the brains integration of sensory information

Top down processing

Perception driven by cognition using background knowledge to influence perception

Selective attention

The focus of conscious awareness on a particular stimulus while ignoring others

Cocktail party effect

Hearing only one person in a room of conversations

Inattentional blindness

Failing to notice a fully visible object because attention is engaged elsewhere

Change blindness

A perceptual phenomenon where a change in a visual stimulus is not noticed by the observer

Transduction

The conversion of sensory stimuli into neural impulses

Absolute threshold

The minimum intensity of a stimulus that can be detected 50% of the time

Signal detection theory

A theory explaining how we discern between important stimuli and background noise

Priming

The activation of certain associations in memory to influence perception

Difference threshold

The minimum difference between two stimuli required for detection 50% of the time

Webers law

A principle stating that the size of the just noticeable difference is a constant proportion of the original stimulus

Sensory adaptation

The process by which our senses adjust to stimuli becoming less sensitive to constant exposure

Bipolar cells

Nerve cells in the retina that act as the primary pathway for visual info to pass from photoreceptors to ganglion cells

Ganglion cells

Neurons in the retina that send visual info from the eye to the brain

Feature detectors

Neurons in the visual correct that respond to specific features of visual stimuli such as edges or movements (shape and stuff)

Parallel processing

The ability of the brain to process multiple stimulus simultaneously

Gestalt

A principle that suggests we perceive whole forms rather than just the sum of their parts

Figure ground

The organization of visual fields into objects that stand out from their surroundings

Grouping

The perceptual tendency to organize stimuli into coherent groups

Gestalt prox

Objects that are close together and perceived as a group

Gestalt continuity

The tendency of the human eye to perceive visual elements as continuous lines or patterns

Gestalt closure

The illusion of seeing an incomplete stimulus as though it were whole

depth perception

The ability to perceive the world in three dimensions and judge distance