Chapter 4 Psychology 175.102 Flashcards
Perception
Perception is the related process by which the brain selects organises and interprets sensations
Sensation
Sensation is the process by which sense organs gather information about the environment and transmit it to the brain for initial processing
Sensory receptors
Specialised cells in the nervous system that transform energy in the environment in to neural impulses that can be interpreted by the brain
Transduction
The process of converting physical energy or stimulus information into impulses
Absolute threshold
The minimum amount of physical energy needed for an observer to notice a stimulus
Signal detection theory
Asserts that judgements about the presence or absence of stimulus reflect the observer’s sensitivity to the stimulus and the observers response bias.
Response bias
The individual readiness to report detecting a stimulus when uncertain
Difference threshold
The lowest level of stimulation required to sense that a change in stimulation has occurred
Just noticeable difference, JND
The just detectable difference between two stimuli
Weber’s law
States that regardless of the magnitude of two stimuli, the second must differ by constant proportion from the first for it to be perceived as different.
Fechner’s law
States that the magnitude of the stimulus grows logarithmically as the subjective experience of intensity grows arithmetically, so that people subjectively experience only a fraction of actual increases in stimulation.
Steven’s Power law
States that subjective intensity increases in a linear fashion as actual intensity grows exponentially.
Wavelengths
Different forms of radiation have waves of different length
Cornea
A tough transparent tissue covering the front of the eyeball
Pupil
An opening in the centre of the iris
Iris
The pigmented tissue that gives the eye it’s blue, green or brown colour
Lens
And elastic, disc shaped structure about the size of lima bean that is involved in focusing the eyes.
Accommodation
The process in which the lens flattens for distant objects and becomes more rounded or spherical for closer objects.
Retina
A light sensitive layer of tissue at the back of the eye that transduces light into visual sensations.
Vitreous humour
The clear liquid in the eye
Rods and cones
Two types of light receptors, or photo receptors, which are named for the distinctive shapes.