Perception - Perception Sensation: stimulus- detection...

This preview shows page 1 - 3 out of 10 pages.

PerceptionSensation: stimulus- detection process by which sense organs respond to & translate environmentstimuli into nerve impulses sent to the brainPerception: active process of organizing stimulus input and giving it meaning (brain interprets rawsensory inputs)The process of sensation to perceptionStimulus reception by sensory receptorsReceptors translate stimulus properties into nerve impulses – transductionFeature detectors analyze stimulus featuresStimulus features are reconstructed into neural representationNeutral representation compared with previous stored information in brainMatching process results in recognition and interpretation of stimuliSensation & DetectionBasic principles that guide sensation in all our sensesTransduction– process by which physical energy is converted to neural impulsesSense receptorsin each of the senses transduce specific stimuliPsychophysics is the study of how we perceive sensory stimuli based on their physical characteristics(Fechner)Detection of sensory input depends on the detectorEvery sense receptor has thresholds for detectionStimulus DetectionAbsolute threshold:lowest level of stimulus that we can detect fifty percent of the time; the minimumamount of stimulation that can be detected; what is the dimmest light, softest sound, weakest smell thatcan be detectedJust noticeable difference (JND):the smallest change in intensity of a stimulus that we can detect(involves Weber’s law); sometimes called difference thresholdWeber’s law: the size of a JND is a constant proportion of the size of an initial stimulus
Signal DetectionSo how do we detect signals when conditions aren’t under experimental control?Signal detection theory= detection of stimuli involves division and sensory processes, which are bothinfluenced by a variety of factors besides stimulus intensityInvolves decision criteriaConservative criteria: one might need to be really certain that a stimulus is present before you will say itis presentLiberal criteria: less stringent standards of accepting if stimulus is presentDecision Criteria: personal standard of certainty before a person will say they detect a stimulus (flexible);situational factors such as consequences also weigh inUsing Signal Detection Theory, we try to account for the influence of decision making processes onstimulus detection

Upload your study docs or become a

Course Hero member to access this document

Upload your study docs or become a

Course Hero member to access this document

End of preview. Want to read all 10 pages?

Upload your study docs or become a

Course Hero member to access this document

Term
Spring
Professor
Kristy Pierce
Tags
Psychology, Perception, fovea, stimulus detection, stimulus detection process

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture