Sensation and Perception Flashcards
PERCEPTUAL CONSTANCY
Ability to recognise objects despite other stimulation
TRANSDUCTION
the process of converting physical energy/ stimulus into neural impulses
SENSATION
Stimulus detection process where sense organs respond to and translate environmental stimuli
ABSOLUTE THRESHOLD
The minimum amount of energy needed to notice a stimulus
THE DIFFERENCE THRESHOLD
the smallest difference between stimuli that people can perceive 50% of the time.
SIGNAL DETECTION THEORY
Asserts that judgements about the presence or absence of stimulus reflect the observer’s sensitivity to the stimulus and the observer’s response bias
Senses
AUDITION: hear sounds as pressure waves
OLFACTION: smell, chemical sense
GUSTATION: taste, chemical sense
TOUCH KINESTHESIS AND EQUILIBRIUM: body senses
Structure of the eye
CORNEA tough transparent tissue
PUPIL opening in the centre of the iris, expand or constrict to regulate the amount of light entering
IRIS pigmented tissue that gives eye colour
LENS disc-shaped structure, assists focus
RETINA transduces light into visual sensations
Structure in the eye
RODS black, white and grey receptors, sensitive to light, function best in dim light
CONES colour receptors concentrated in FOVEA, function best in bright illumination
BIPOLAR CELLS combine info from many receptors and produce graded potentials on GANGLION CELLS which integrate information from multiple BIPOLAR CELLS
Trichromatic theory
suggests the eye contains three types of receptors most sensitive to red, green and blue wavelengths
OPPONENT PROCESS THEORY
suggests colours we experience reflect three opposing colour systems: a blue–yellow, red–green and black–white system
BOTTOM-UP PROCESSING
begins with raw SENSORY DATA that feed ‘up’ to the brain. Break down sensation first.
TOP-DOWN PROCESSING
begins with the observer’s expectations, knowledge, and WHOLE PICTURE. Break down sensation later.
GESTALT PRINCIPLES
Argue that the whole is more than the sum of its parts
FORM PERCEPTION refers to the organisation of sensations into meaningful shapes and patterns
FORM PERCEPTIONS
SIMILARITY: group similar elements together
PROXIMITY/CONNECTEDNESS: group together objects
CONTINUITY: continuous lines or patterns rather than discontinuous elements. Cross on a circle rather than a circle in quarters with small extensions.
SIMPLICITY: the simplest pattern possible
CLOSURE: perceives incomplete figures as complete.
