Chapter 4: Sensation And Perception Flashcards
Sensation
The process by which our sensory organs receive stimulus energies from the environment and transduce them into electrical energy of the nervous system.
Transduction
The transformation of sensory stimulus energy from the environment into neural impulses.
Perception
The neural processing of electrical signals form an internal mental representation inside your brain of what’s on the outside.
Psychophysics
The study of the relationship between the physical characteristics of environmental stimuli and our mental experience of them.
Absolute threshold
The minimum amount of stimulation necessary for someone to detect a stimulus half of the time.
Signal detection theory
An approach to measuring thresholds that takes into account both the intensity of the stimulus and psychological biases for the more accurate assessment.
Difference threshold
The minimum difference required between two stimuli for an observer to detect a difference half the time.
Just-noticeable difference (JND)
The minimum difference required between two stimuli for an observer to detect a difference half of the time.
Weber’s law
The observation that the likelihood of perceiving a stimulus change is proportional to the magnitude of the stimuli.
Adaptation
A phenomenon whereby an individual stops noticing a stimulus that remains constant over time, resulting in enhanced detection of stimulus changes.
Wavelength
The distance between any two consecutive crests or through of a wave.
Frequency
The number of cycles per second of a wave.
Amplitude
The height of crests of a wave.
Pupil
A hole in the iris where light enters the eye.
Iris
The coloured muscle circling the pupil.
Lens
A membrane at the front of the eye that focuses the incoming light on the retina.
Accommodation
Adjustment of the len’s thickness by specialized muscles in order to change the degree to which it bends light.
Retina
A surface on the back of the eye that contains the photoreceptor cells.
Rods
Photoreceptor cells that primarily support nighttime vision.
Cones
Photoreceptor cells that are responsible for high-resolution colour vision.
Optic nerve
A bundle of axons that converge from the retina and transmit action potentials to the brain.
Blind spot
An area in the middle of the visual field where there are no photoreceptors and no information can be received.
Fovea
A small pit in the center of the retina that is densely packed with cones.
Trichromatic theory
A theory of colour perception stating that three types of cone cells, each most sensitive to a specific wavelength of light, work together to produce our perception of a multicoloured world.
Opponent-process theory
A theory of colour perception stating that information from the cones is separated into three sets of opposing or opponent channels in the ganglion cell layer.
Feature detectors
Specialized cells in the visual cortex that respond to basic features such as lines, edges, and angles.
Visual association cortex
The region of the brain where objects are reconstructed from prior knowledge and information collected by the feature detectors.
Prosopagnosia
A visual disorder in which individuals are unable to recognize the identity of faces.
Phi phenomenon
A visual illusion in which the flashing of separate images in rapid succession is perceived as fluid movement.
Pitch
The perceptual quality of sound that makes a flute sound high and a tuba low.
Middle ear
The portion of the ear containing the eardrum and ossicles.
Ossicles
Three tiny bones in the ear-the hammer, anvil, and stirrup-that act as levers to amplify incoming sound waves.
Inner ear
The innermost part of the ear, where the cochlea resides.
Cochlea
A spiral structure in the inner ear where the basilar membrane, containing auditory sensory neurons, is located.
Basilar membrane
A structure in the cochlea where the auditory cilia, or auditory sensory neurons, are located.
Frequency theory
A theory of pitch perception stating that the brain uses the frequency of auditory sensory neuron firing to indicate pitch.
Place theory
A theory of pitch perception stating that different pitches arise from stimulation at different places along the basilar membrane.
Primary auditory cortex
The region of the brain, located in the temporal lobe, where sound is processed.
Tonotopic organization
The arrangement of the auditory cortex such that nearby frequencies are processed near each other in the brain, resulting in a sound map.
Tactile sense
The sense of touch.
Primary somatosensory cortex
The region of the brain where the processing of touch sensations occurs.
Somatosensory homunculus
A depiction of how the body is represented by the brain, proportional to the amount of cortex devoted to each body part.
Proprioception
The sensory system responsible for awareness of body positions.
Vestibular system
The sensory system primarily responsible for balance.
Kinesthesis
The senses responsible for monitoring the position and movement of the body, including proprioception and the vestibular system.
Olfaction
The sense of smell.
Epithelium
A mucous membrane in the nasal cavity that contains the olfactory receptor neurons.
Olfactory bulb
A structure just above the nasal cavity where information is communicated to the primary olfactory cortex via the olfactory tract.
Glomeruli
A spherical cluster of neurons in the olfactory bulb.
Primary olfactory cortex
The region of the brain, located in the anterior temporal lobe, where smell is processed.
Gustation
The sense of taste.
Gestalt psychology
A school of psychological thought that attempted to explain how various elements group together to form objects, arguing that perception is more than a simple piecing together of building blocks.
Binocular cues
Depth information gathered from the separation between an individuals two eyes.
Binocular disparity
The magnitude of difference between the images projected on an individuals two eyes.
Monocular cues
Depth information that can be gathered by only one eye.
Size constancy
The phenomenon whereby the brain adjusts its perception of distance in order to perceive an object’s actual size as constant, taking into account changes in retinal size.
Colour constancy
The phenomenon whereby the brain adjusts its perception of colour to hold it constant, taking into account changes in lighting conditions.
Perceptual set
A predisposition that influence what we perceive based on recent experience or context.
