Sensations and preceptions Flashcards
sensation definition
the reception of stimulation from an environemnet
- detection of physical energy by sense organs which send information to the brain
Preception definiton
interpretation of the sensory informaion which often happens as a automatic process (pattern recognition)
Transduction definition
the process of converting an external stimulus into electrical activity within neurons
Sensory adaption
the idea that activiation is greatest when stimulus first is detected
definition of psychophysics
the study of how we perceive sensory stimuli based on their physical characterisitics
absolute thereshold definition
the lowest level of stimulus needed to be detected by the nervous system 50% of the time
just noticeable difference
the smallest change in the intensity of a stimulus that we can detect
webr’s law
the constant proportional relationship between the JND and the orginal stimulus intensity
photoreceptor
a specialized neuron that convert light into electrical signals that start transduction
bottom up processing
analysis and integration of basic features into a perceptual unit (when features combine to form an object)
hierarchial organization
form of perceptual units through a process of increasingly complex connection between simple units (occurs in the visual cortex, temporal and parietal lobes)
paralle processing
when a system which has many different steps happens simultaneously (allows for perception of many different features)
top-down processing
when context and higher level knowledge influence lower level process
principal of simplicity
we have sensory input our perceptual systems usually tries to create a percept that is simple orderly and stable
law of proximity
when objects that are physically close to each other tend to be perceived as unified wholes or groups
the law of closure
when objects are percieved as whole even if there are not complete
the law of good continuation
the ability to perceive objects as forming smooth and continous patterns
law of symmetry
when objects are around a centre point form a group or whole
law of figure-ground segregation
the tendancy to structure the visual field into two parts (figure and a background
prosopagonosia
a deficit in recongnizing faces
apperceptive agnpsoa
defict in recongizing patterns
assoicative agnosia
deficit in associating meaning with pattern
place theory (pitch perception)
different frequencies stimulated by different locations on the basier membrane
frequency theory
tones with different frquencies cause neurons to fire at different rates
