Ch 3 Flashcards - Intro to Psych

Sensation

The process by which receptors in the sensory organs (the eyes, ears, nose, mouth, skin, and other tissues) receive and detect stimuli

Perception

The organization and interpretation of sensory stimuli by the brain

Bottom-up Pricessing

Taking basic information about incoming sensory stimuli and processing it for further interpretation

Top-down Processing

Drawing on past experiences and knowledge to decipher and interpret sensory information

Transduction

The process of transforming stimuli into neural signals

Absolute Thresholds

The weakest stimuli that can be detected 50% of the time

Sensory Adaption

The process through which sensory receptors become less sensitive to constant stimuli

Difference Threshold

The minimum difference between two stimuli that can be noticed 50% of the time

Weber’s Law

States that each of the senses has its own constant ratio determining difference thresholds

Signal Detection Theory

Explains how internal and external factors influence our ability to detect weak signals in the environment

Wavelength

The distance between wave peaks (or troughs)

Hue

The color of an object, determined by the wavelength of light it reflects

Amplitude

The height of a wave; distance from midpoint to peak, or from midpoint to trough

Saturation

Color purity

Cornea

The clear, outer layer of the eye that shields it from damage and focuses incoming light waves

Iris

The part of the eye responsible for changing the size of the pupil

Accommodation

The process by which the lens changes shape in order to focus on objects near and far

Retina

The layer of the eye containing photoreceptor cells, which transducer light energy into neural activity

Photoreceptors

Specialized cells in the retina that absorb light energy and turn it into electrical and chemical signals for the brain to process

Rods

Photoreceptors that enable us to see in dim lighting; not sensitive to color, but useful for night vision

Cones

Photoreceptors that enable us to sense color and details

Optic Nerve

The bundle of axons from ganglion cells leading to the visual cortex

Blind spot

A hole in the visual field caused by the optic disc (the location where the optic nerve exits the retina)

Dark Adaption

Process by which the eyes adjust to dark after exposure to bright light

Light adaption

Process by which the eyes adjust to light after being in the dark

Feature Detectors

Neurons in the visual cortex specialized in detecting specific features of the visual experience, such as angles, lines, and movements

Trickromatic Theory

Suggests that perception of color results from the activation of three cone types, which are sensitive to wavelengths in the red, green, and blue spectrums

Afterimage

An image that appears to linger in the visual field after its stimulus, or source, is removed

Opponent-process Theory

Suggests that perception of color derives from a special group of neurons that respond to opponent colors (red-green, blue-yellow)

Audition

The sense of hearing

Pitch

The degree to which a sound is high or low, determined by the frequency of its sound wave

Frequency

The number of sound waves passing a given point per unit of time; higher frequency is perceived as higher pitch, and lower frequency is perceived as lower pitch

Cochlea

Fluid-filled, snail-shaped organ of the inner ear lined with basilar membrane

Place Theory

States that pitch corresponds to the location of the vibrating hair cells along the cochlea

Frequency Theory

States that pitch is determined by the vibrating frequency of the sound wave, basilar membrane, and associated neural impulses

Volley Principle

States that neurons work together so their combined firing reaches frequencies higher than one neuron can achieve alone

Olfaction

The sense of smell

Gestation

The sense of taste

Gate-control Theory

Suggests that the perception of pain will either increase or decrease through the interaction of biopsychosocial factors; signals are sent to open or close “gates” that control the neurological pathways for pain

Kinesthesia

Sensory system that conveys information about body position and movement

Proprioceptors

Specialized nerve endings primarily located in the muscles and joints that provide information about body location and orientation

Vestibular Sense

The sense of balance and equilibrium

Illusion

A perception that is inconsistent with sensory data

Gestalt

The natural tendency for the brain to organize stimuli into a whole, rather than perceiving the parts and pieces

Figure-ground

A central principle of Gesalt psychology, involving the shifting if focus; as attention is focused in one object, all other features drop or recede into the background

Depth Perception

The ability to perceive three-dimensional objects and judge distances

Binocular Cues

Information gathered from both eyes to help judge depth and distance

Convergence

A binocular cue used to judge distance and depth based on the tension of the muscles that direct where the eyes are focusing

Retinal Disparity

A binocular cue used to determine the distance of objects; the difference between the images seen by the right and left eyes

Monocular Cues

Depth and distance cues that require the use of only one eye

Perceptual Constancy

The tendency to perceive objects in our environment as stable in terms if shape, size, and color, regardless of changes in the sensory date received

Shape Constancy

An object is perceived as maintaining its shape, regardless if the image projected in the retina

Size Constancy

An object is perceived as maintaining its size, regardless of the image projected on the retina

Color Constancy

Objects are perceived as maintaining their color, even with changing sensory data

Perceptual Set

The tendency to perceive stimuli in a specific manner based on past experiences and expectations