Chapter 4 - Sensation and Perception Flashcards
the stimulation of sense organs.
Sensation
translating sensory input into something meaningful, such as your best friend’s face or other environmental stimuli is an example of:
perception
the selection, organization, and interpretation of sensory input
Perception
involves the absorption of energy, such as light or sound waves, by sensory organs, such as the ears and eyes
Sensation
a condition in which perceptual or cognitive activities (e.g., listening to music, reading) trigger exceptional experiences (e.g., of colour, taste)
Synesthesia
specific stimuli are consistently and involuntarily associated with emotional responses
emotional synesthesia
a condition in which words, letters, or digits are associated reliably with specific colours
Grapheme–colour synesthesia
when tastes lead to specific feelings
taste–touch synesthesia
when words or names lead to taste sensations
word–taste synesthesia
when sounds/musical notes lead to colour sensations
sound–colour synesthesia
the study of how physical stimuli are translated into psychological experience
psychophysics
is a dividing point between energy levels that do and do not have a detectable effect.
Threshold
the minimum amount of stimulation that an organism can detect
Absolute threshold
is the smallest difference in the amount of stimulation that a specific sense can detect.
Just Noticeable Difference (JND)
states that the size of a just noticeable difference is a constant proportion of the size of the initial stimulus
Weber’s Law
Proposes that the detection of stimuli involves decision processes as well as sensory processes, which are both influenced by a variety of factors besides stimulus intensity
Signal-detection theory
the registration of sensory input without conscious awareness
Subliminal perception
is a gradual decline in sensitivity due to prolonged stimulation.
Sensory adaptation
Neural tissue that receives light
Retina
a transparent “window” at the front of the eye
Cornea
the transparent eye structure that focuses the light rays falling on the retina.
Lens
occurs when the curvature of the lens adjusts to alter visual focus. When you focus on a close object, the lens of your eye gets fatter (rounder) to give you a clear image. When you focus on distant objects, the lens flattens out to give you a better image of the objects
Accomodation
the opening in the centre of the iris that helps regulate the amount of light passing into the rear chamber of the eye.
Pupil
coloured ring of muscle surrounding the pupil
Iris
The movements that occus when our eyes are scanning the visual environment and making brief fixations at various parts of the stimuli
Saccades
The effect that occurs when horizontal eye movements are elicited before memory retrieval
Saccade induces retrieval enhancement effect
a place in the retina where the optic nerve fibres exit the eye
Optic Disk
Area of the optic disk where there are no photoreceptors
Blindspot
Photoreceptors responsible for daylight and colour vision
Cones
Photoreceptors responsible for night / peripheral vision
Rods
The area of the retina (towards the center) that contains exclusively cones. Highest level of acuity
Fovea
The retinal area that, when stimulated, affects the firing of that cell. Multiple signals are funneled to a particular visual cell in the retina (or ultimately in the brain)
Receptive field
the point at which the optic nerves from the inside half of each eye cross over and then project to the opposite half of the brain.
Optic chiasm
Major (90%) visual pathway:
Eyes>Thalamus>Synapse>Occipital lobe (proimary visual cortex)
Lateral Geniculate Nucleus (LGN)
Secondary visual pathway (10%)
Eyes>Midbrain>Thalamus>Occipital lobe
Superior Colliculus
Vision for action pathways (2)
Dorsal pathway - where
Vision for perception pathways (2)
Ventral pathway - what
the pathway that creates an internal representation of the real world
Perception (ventral, what)
The pathway that docuses on controlling actions directed towards objects
Vision for action (dorsal, where)
works by removing some wavelengths of light, leaving less light than was originally there. (paints adding together)
Subtractive colour mixing
works by superimposing lights, putting more light in the mixture than exists in any one light by itself (think spotlights layering)
Additive colour mixing
theory that states that we perceive color through the combined activity of three types of cone cells in our eyes, each sensitive to red, green, or blue light
Trichromatic theory
Variety of deficiencies that alter abilities to distinguish colours
Colour-blindness
People who are insensitice to one of the primary colour channels (RBG)
Dichromats