Introduction to Psychology: Sensation and Perception

Sensation

Process where stimuli FROM THE ENVIRONMENT is brought into the body by one of the 5 senses

5 SensesSight, Taste, Smell, Touch, Hearing

5 Senses

Bottom-Up Processing

Starts from the SENSORY RECEPTORS and works its way up to the brain

Perception

Process where raw data sent from 5 senses is organized and INTERPRETED, enabling us to recognize meaningful objects and events

Top down Processing

Background information and past experiences influences perception

Selective Attention

Focusing on conscious awareness on a PARTICULAR STIMULI

Cocktail Party Effect

Your ability to attend to only one voice among many

Inattentional Blindness

failing to see visible objects when attention is directed elsewhere

(Ex: Dancing bear)

Change Blindness

Failing to notice a change in the environment

(Ex: spot the differences )

Absolute Threshold

The lowest level you can detect. [light, sounds, pressure, taste or odor.]

(Ex: Volume on radio video)

Subliminal Threshold

Below absolute threshold for awareness

(Ex:)

Difference Threshold

Just noticeable difference

(Ex:Music, Shoelaces, hallway voices)

Sensory Adaption

Diminished SENSitivity as a result of frequent exposure

(Ex: being numb to bad or good smells)

Bored Sense

Attention on important things

Transduction

Conversion of ONE FORM OF ENERGY TO ANOTHER for brain to use

(Ex: Vision --> Light energy

Hearing--> Sound waves )

Perceptual Set

A mental predisposition to perceive SomEThing one way or another.

Signal Detection Theory

A theory that predicts how and when we detect the presence of a faint stimulus among the back round noise

Cornea

The clear curved bulge on the front of the eye that BENDS LIGHT RAYS to begin FOCUSING THEM

Iris

A ring of muscle tissue that forms the COLORED PORTION of the eye and regulates the size of the pupil

Pupil

The adjustable opening IN THE CENTER OF THE IRIS, which controls the amount of LIGHT entering the eye.

Lens

A transparent structure behind the pupil in the eye that CHANGED SHAPE TO FOCUS IMAGES ON THE RETINA

Retina

The light-sensitive surface at the back of the eyeball; Begins processing visual information.

Contains receptor rods, cones, neurons

Accomodation

changes curvature to focus on NEAR OR FAR OBJECTS

Ganglion

Behind the bipolar cells. Sends axons and form the optic nerve which carries info to the brain

Bipolar cells

Middle layer of the retinal cells. It is fed info from the rods and cones and sends it to the ganglion cells

Rods

Visual receptor cells located in the retina that CAN DETECT ONLY BLACK WHITE AND GRAY

Cones

Visual receptor cells located in the center of the retina that CAN DETECT SHARP DETAILS AND COLOR

Optic Nerve

Nerve that CARRIES VISUAL INFORMATION FROM THE EYE TO OCCIPITAL LOBES OF THE BRAIN

Occipital Lobes

The visual processing center of the brain.

Feature detector

Nerve cells in Occipital Lobe that responds to features such as SHAPE, ANGLE, AND MOVEMENT

Blind spot

When the optic nerve leaves the eye (no receptor cells)

Proximity

Objects that are near each other tend to be grouped together (same group)

Continuity

Smooth patterns

Closure

Full shapes

Parallel Processing

Divides a visual scene into motion, form, color and depth

Depth perception

The ability to perceive the world in three dimensions (3D) and the distance of an object.(although the images that strike the retina are two-dimensional)

Monocular Cues

Depth cues that require the use of one eye (Depth cues available to both eyes such as size, lighting, shading)

Binocular Cues

Depth cues that require the use of both eyes (using two eyes to judge depth) (Depth cues available to both eyes such as size, lighting, shading)

Retinal Disparity

comparing images in both retinas, to perceived depth. (Computes distance)

Visual Cliff

A lab device for testing depth perception in infants and young animals

Figure-Ground

organization of visual field into objects that stand out from their surroundings

Opponent Process Theory

A theory of color vision that says color is processed by cones organized in opponent pairs. Light stimulates one half and cancels out the other

Young Helmholtz (3 Color) Theory

Retina contains 3 different color receptors, when stimulated together = perception of any color

Fovea

Retinas area of central focus

Intensity

Amount of energy in light waves

Wave Lengths

Distance from peak of one light or sound wave to the peak of the next. Determines hue.

Hue

Color we experience