Psychology - Sensation & Perception

Sensation

Detecting physical energy or stimuli from the environment through the senses.

Perception

Giving meaning or interpretation to sensory information.

Sensation

receiving sensory information

Perception

interpreting what that information means.

Stimulus

A form of physical energy or environmental information that can be detected by the senses.

Receptor

A specialized sensory structure or cell that detects a particular type of stimulus.

Neural Processing

The process by which sensory information is transmitted and processed through neurons and the nervous system.

Neuron

A specialized cell that communicates and transmits information throughout the nervous system.

Synapse

The point of communication between neurons.

Absolute Threshold

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

Experience and Perception

Previous experiences learning and personality can influence how a person interprets sensory information.

Impulsivity

Responding quickly to a perception or interpretation without taking enough time to reflect or verify it.

Illusion

A sensory experience in which a real external stimulus exists but is perceived incorrectly or distorted.

Hallucination

A sensory experience that occurs without a corresponding external stimulus.

Delusion

A strongly held false or unsupported belief that is not supported by available evidence or reality.

Extrasensory Perception (ESP)

The alleged ability to obtain information beyond the ordinary sensory capacities.

Clairvoyance

claimed ability to perceive information about something without using the ordinary senses.

Telepathy

claimed ability to communicate or receive thoughts directly from another person's mind.

Parapsychology

The study of alleged paranormal or extraordinary phenomena such as ESP and other experiences beyond ordinary sensory processes.

Gestalt Psychology

An approach emphasizing that the brain organizes sensory information into meaningful patterns and wholes.

Gestalt Principle of Proximity

Objects that are close to one another are perceived as belonging together.

Gestalt Principle of Similarity

Objects that look similar are perceived as belonging to the same group.

Gestalt Principle of Continuity

The brain tends to perceive continuous lines or patterns rather than disconnected pieces.

Gestalt Principle of Closure

The brain tends to mentally complete incomplete figures or patterns.

Gestalt Principle of Figure-Ground

The brain distinguishes a main object or figure from the surrounding background.

Size Constancy

The tendency to perceive an object as maintaining the same physical size even when its retinal image changes because of distance.

Shape Constancy

The tendency to perceive an object as maintaining the same shape even when its retinal image changes because of viewing angle.

Sensation Example

Seeing light hearing sound smelling an odor tasting food or feeling pressure are examples of sensation.

Perception Example

Recognizing a sound as an ambulance siren or interpreting a taste as chocolate.

Illusion Example

Seeing a cloud and interpreting its shape as a dragon.

Hallucination Example

Hearing a voice when there is no external person or sound producing it.

Absolute Threshold Example

Detecting a very quiet ticking clock in a silent room can illustrate the absolute threshold.

Figure-Ground Example

The vase/two-faces image demonstrates how the brain can alternate between what it treats as the figure and what it treats as the background.

Key Difference: Sensation vs. Perception

Sensation = RECEIVE. Perception = INTERPRET.

Key Difference: Illusion vs. Hallucination

Illusion = REAL stimulus + WRONG/DISTORTED interpretation. Hallucination = NO corresponding external stimulus.

Key Difference: Hallucination vs. Delusion

Hallucination = SENSE. Delusion = BELIEF.