Unit 2 Sensation & Perception (PSYCHOLOGY)


The process by which our sensory receptors receive and transmit stimulus energies from our environment to our brain.


The mental organization and interpretation of sensory information. Perception results from a combination of biological, psychological, and social-cultural influences.

Bottom-up processing

analysis of perception that begins with sensory input.

Top-down processing

analysis of perception that begins with the brain and flows down, filtering information through our experience and expectations.


The process of perceiving some sensations but not others.

.Divided Attention

Focusing awareness on multiple tasks.

Absolute threshold:

The minimum stimulation needed for a person to detect a particular light, sound, pressure, taste, or odor 50% of the time.

Selective Attention

the focusing of conscious awareness on a particular stimulus.

Difference threshold

The minimum difference a person can detect between any two stimuli 50% of the time.


Stimulation below one's absolute threshold for conscious awareness.

Sensory adaptation:

A diminishing sensitivity to an unchanging stimulus.

Perceptual Constancy

allows us to see familiar objects as having standard shape, size, color, or location regardless of changes in the angle of perspective, distance, or lighting.

Olfactory bulb

sends electrical signals from the chemical receptors in the nose to the main cortex of the brain.

taste buds

receptors on the tongue which react to sweet, sour, salty, bitter, and umami (savory meaty taste).

Sensory Interaction

the principal that one sense can influence another. Smell + taste + texture = taste.


your sense of the position and movement of your body parts

Vestibular sense

your sense of your head's position and movement. Controlled by sacs of fluid in your inner ear.


your body's way of telling you something is wrong.


the psychological theory that our brain has a tendency to perceive stimuli as whole objects and not a group of disconnected objects.


something that can be interpreted in 2 or more ways.


our brain organizes stimulus into a figure seen against a ground.


our brain groups similar stimulus together.


our brain fills in gaps to create a complete, whole object.


our brain groups stimulus that are near each other.


When figures are somehow iconnected or linked, we perceive them as a single unit.


our brain groups stimulus into continuous patterns rather than discontinuous ones.

Binocular depth cues

depth cues that depend on the use of 2 eyes.

Retinal disparity

the brain uses the slightly different viewpoints of our two eyes as a clue to determine depth.

Monocular depth cues

depth cues that depend on the use of only 1 eye.

Relative height

our brain interprets objects higher in our field of vision as further away.

Relative size

our brain assumes that as the perceived size of an object gets smaller, its getting further away.


if one object partially blocks our view of another object, our brain perceives the blocking object as closer.

Linear perspective:

when parallel lines, like a railroad track, appear to move closer together, our brain perceives that the more the lines converge, the further away they are.

Relative motion

the apparent movement of stationary objects when observed by someone who is themselves moving.

Light & shadow

our brain perceives the dimmer of two similar objects as further away.

.Nature-nurture debate

an ongoing philosophical and psychological question of whether our perceptual abilities are inborn or the result of experience.

Perceptual Set

A mental predisposition based on experience to perceive one thing and not another.

Context effects

the effect of immediate surrounding and circumstances on our perceptions of objects and events.


a complex knowledge structure of things we encounter in our everyday lives.

Constructive memory

when we use our present knowledge to rewrite what we recall we perceived.

Functional perception

involves placing items in one or more categories and then applying what we know about those categories to arrive at our perception. (top-down perception)

Here and Now perception

involves trying to perceive only our sensory inputs without applying mental filtering such as past experience, knowledge, or value judgments. (bottom-up perception)