AP Psychology Unit 3- Sensation and Perception

Sensation

the process of the sensory organs transforming physical energy into neurological impulses the brain interprets as the five senses of vision, smell, taste, touch, and hearing

Absolute Threshold

the smallest level of energy required by an external stimulus to be detectable by the human senses, including vision, hearing, taste, smell and touch

Retina

the area in back of the eye that contains your rods and cones

Cones

specialized types of photoreceptors that work best in bright light conditions

Difference Threshold

the minimum amount of change needed in stimuli in order for the subject to sense it 50% of the time

Perception

our recognition and interpretation of sensory information

Rods

specialized photoreceptors that work well in low light conditions

Opponent Process Theory (color)

a theory of emotional and motivational states that is proposed by psychologist Richard Solomon. According to this theory, emotions are paired as opposites such as. Happiness and sadness. Fear and relief. Pleasure and pain.

Fovea

a small depression within the neurosensory retina where visual acuity is the highest, responsible for central vision

Trichromatic Theory

human eyes only perceive three colors of light: red, blue, and green

Cochlea

relays information about the specific area, or place that is most activated by the incoming sound

Perceptual Constancy

the tendency of animals and humans to see familiar objects as having standard shape, size, colour, or location regardless of changes in the angle of perspective, distance, or lighting

Monocular Cues

the clues that allow us to see depth through one eye

Pheromones

substances which are secreted to the outside by an individual and received by a second individual of the same species, in which they release a specific reaction

Transduction

the process through which something changes in a specific way. It can change in form, shape, place, or idea

Weber’s Law

historically important psychological law quantifying the perception of change in a given stimulus. The law states that the change in a stimulus that will be just noticeable is a constant ratio of the original stimulus. It has been shown not to hold for extremes of stimulation

Binocular Cues

visual information taken in by two eyes that enable us a sense of depth perception, or stereopsis

Place Theory

proposes an explanation of how human beings perceive pitch. According to this theory, the hair cells and nerve fibers of the cochlea are divided into different regions that detect specific sound frequencies

Retinal Disparity

a binocular cue used to perceive depth between two near objects. It does so by comparing the different images from both retinas. Each eye receives different images because they are usually around two and half inches apart

Taste Buds

nerve endings that are located on the tongue and back of the throat and are responsible for our sensation of taste

Pitch

the perceptual correlate of waveform periodicity, or repetition rate

Bottom Up Processing

the sensory perception of the outside stimuli, the stimuli being processed in the part of the brain responsible for that sense, and then deriving meaning from analysis based only on data

Feature Detector

individual neurons—or groups of neurons—in the brain which code for perceptually significant stimuli

Gate Control Theory

a mechanism, in the spinal cord, in which pain signals can be sent up to the brain to be processed to accentuate the possible perceived pain, or attenuate it at the spinal cord itself

Psychophysics

study of quantitative relations between psychological events and physical events or, more specifically, between sensations and the stimuli that produce them

Sensory Adaptation

a reduction in sensitivity to a stimulus after constant exposure to it

Signal Detection Theory

relates to the idea that the intensity of the stimuli and the psychological and physical state of the person contribute to whether or not the person is able to detect the stimuli

Top Down Processing

a cognitive process that initiates with our thoughts, which flow down to lower-level functions, such as the senses

Accommodation (perceptual)

Rather than make the new information fit into an existing schema, you change the schema in order to accommodate the new information

Frequency Theory

a sound heard is replicated and matched by the same amount of nerve impulses that are then transmitted to the brain

Habituation

a decrease in response to a stimulus after repeated presentations

Lens

a clear, curved structure at the front of the eye behind the pupil. It focuses light rays that enter the eye through the pupil, making an image on the retina

Optic Nerve

comprised of millions of nerve fibers that send visual messages to your brain to help you see

Pupil

The round opening in the center of the iris, changes size depending on the amount of light

Vestibular Sense

detect the position and movement of our head in space

Blind Spot

the point of entry of the optic nerve on the retina, insensitive to light

Dark Adaptation

the process whereby the retina adapts to decreasing levels of illumination

Iris

a flat, colored, ring-shaped membrane behind the cornea of the eye, with an adjustable circular opening (pupil) in the center

Olfaction

the sense of smell detects and discriminate odors as well as social cues which influence our innate re-sponses

Convergence

how the brain combines different sensory information — like what we see, hear, and feel — to understand and interpret our surroundings

Hue

the experience that we describe with color name labels such as red or blue

Shape Constancy

the tendency for a familiar object's shape to be perceived as constant when observed from various angles, positions and orientations

Size Constancy

occurs when an observer is familiar with an object, so that the object appears to have a constant size when viewed from various distances

Cornea

the transparent part of the outer covering of the eye, through which light first passes

Subliminal Perception

the processing of information by the brain without conscious awareness

Gustav Fechner

believed that the mind is capable of measurement using perception and sensation and that psychology could be a quantified science

David Hubel

studied how the brain processes information in the visual system

Ernst Weber

defines the perception of change we feel when there is a stimulus

Torsten Weisel

studied visual information processing and development in the US during the twentieth century. He performed multiple experiments on cats in which he sewed one of their eyes shut and monitored the response of the cat's visual system after opening the sutured eye

Gibson

believed in the idea that we perceive simply by using the information we receive through our senses and this is enough information for us to make sense of the world around us