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.
Bipolar cells
Information from rods and cones are transmitted to these, then onto ganglion cells
Ganglion cells
These integrate information from many bipolar cells
Optic nerve
Made up of axons from many ganglion cells, this optic nerve carries visual information to the brain
Fovea
The central region of the retina. Most sensitive to small detail
Blindspot
The point at which the optic nerve leaves the eye.
What pathway of vision
Involved in determining what an object is.
Where pathway of vision
Involved in locating an object in space, following is movement, and guiding movement towards it.
Feature detectors
Feature detectors in the primary visual cortex respond only when stimulation in their respective field matches a particular pattern or orientation.
Hue
What people mean by colour. That is whether an object appears blue, red, violet and so on.
Saturation
The extent to which colour is diluted with a white or black, or saturated with its own wavelength
Lightness
The extent to which a colour is light or dark
Trichromatic theory of colour
According to this theory the eye contains three types of receptors, which are most sensitive to wavelengths experienced as red, green or blue.
Opponent-process theory
According to this theory the colours we experience (and the after image we perceive) reflect three antagonistic colour systems; a blue-yellow, red-green and black-white system.
Audition
Hearing
Sound waves
The way in which sound travels, which occur as a vibrating object sets air particles in motion.
Cycles
Each round of expansion and contradiction of the distance between molecules of air
Frequency
A measure of how often a wave cycles. Frequency is expressed in hertz.
Pitch
The quality of the tone, from low to high.
Complexity
Refers to the extent to which sound is composed of multiple frequencies, and corresponds to the psychological property of timbre.
Timbre
The texture of sound
Amplitude
Refers to the height and depth of a wave, that is, the difference between its maximum and minimum pressure level. The amplitude of a soundwave corresponds to the psychological property of loudness.
Transduction of hearing
Pinnas Eardrum or tympanic membrane Cochlea Auditory receptors or hair cells Sensory neurons Auditory nerve Medulla Splits to the midbrain - inferior colliculus Splits to the thalamus. Then the primary auditory cortex
Cochlea
A 3 chambered tube in the inner ear shaped like a snail and involved in the transduction of sound.
Place theory of sensing pitch
Best explains transaction at high frequencies, different areas of the basilar membrane respond to different frequencies.
Frequency theory of hearing pitch
Best explains transduction at low frequencies, the rate of vibration of the basilar membrane transforms frequency into pitch.
Sound localisation
Identifying the location of the sound in space: differences between the two ears in loudness and timing of the sound.
Olfaction
Smell
Pheromones
Scent messages detected through an auxiliary olfactory system that regulate the sexual behaviour of many animals and direct a variety of behaviours in insects
Transduction of smell
Molecules in the air Olfactory epithelium Olfactory mucus Olfactory receptor cells Olfactory nerve Olfactory bulb Olfactory tract Primary olfactory cortex Splits to amygdala Splits to thalamus
Gustation
Taste
Tastebuds
Where transduction of taste occurs
Transduction of taste
Molecules in saliva Taste buds Taste receptors Gustily nerve Medulla and pons Splits to limbic system Splits to thalamus. Then to primary gastric cortex
Proprioceptive senses
Vestibular sense. Provides information about the position of the body in space by sensing gravity and movement.
Kinaesthesia. Provides information about the movement the position of the limbs and other parts of the body relative to one another.
