Unit 4 vocab

Sensation

Sensation

Occurs when anytime a stimulus activates a receptor(How you make sense of it)

Sensory Receptors

a nerve ending that sends signals to the. central nervous system when it is stimulated

Perception

Organization of sensory information into a meaningful experience

Bottom-up processing

Starts at your sensory receptors and works up to higher levels of processing 

Top-down processing

You have already experienced it, going off prior experience.

Selective Attention

The focus of conscious awareness on a particular stimuli

Inattentional blindness

Failing to see visible objects when our attention is directed elsewhere

Change blindness

example of inattentional blindness, failure to notice something changes  in the environment 

Transduction

Conversion of one form of energy into another - transformation of stimulus energies into neural impulse our brain can interpret

Absolute tresholds

The weakest amount of stimulus required to produce a sensation

Signal detection theory

predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise) Assumes that there is no single absolute threshold and that detection depends partly on a person's experience, expectation, motivation, and level of fatigue

Subliminal

below one's absolute threshold for conscious awareness

Difference threshold

Minimum amount of difference a person can detect between two stimuli 50% of the time

Webers law

The larger or stronger stimulus, the larger the change required for a person to notice that anything has happened to it

Sensory adaption

diminished sensitivity as a consequence of constant stimulation

Figure - ground

the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground).

Depth perception

the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance

Visual Cliff

a laboratory device for testing depth perception in infants and young animals

Binocular cue

depth cues, such as retinal disparity and convergence, that depend on the use of two eyes

Retinal disparity

a binocular cue for perceiving depth; by comparing images from the two eyeballs, the brain computes distance - the greater the disparity (difference) between the two images, the close the object

Wavelength

the distance from the peak of one light or sound wave to the peak of the next

Cornea

the transparent layer forming the front of the eye.

Pupil

the adjustable opening in the center of the eye through which light enters

Retina

the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information

Lens

the transparent structure behind the pupil that changes shape to help focus images on the retina

Rods

retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond

Cones

retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations.

Optic nerve

nerve responsible for carrying impulses for the sense of sight from the retina to the brain

Frequency

the number of complete wavelengths that pass a point in a given time (for example, per second)

Pitch

how high or low a sound is

Cochlea

a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

Sensorineural hearing loss

hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness

Conduction hearing loss

hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea

Gate-control theory

Melzack and Wall's theory that the spinal cord contains a neurological "gate" that blocks or allows pain signals to pass on to the brain.

Olfaction

the action or capacity of smelling; the sense of smell

Kinesthesia

awareness of the position and movement of the parts of the body by means of sensory organs (proprioceptors) in the muscles and joints.

Vestibular sense

the sense of body movement and position, including the sense of balance