Study Guides (238,613)
Canada (115,253)
Psychology (919)
PSYC 2390 (35)
Lana Trick (30)

PSYC2390 CH notes (Pre midterm 1).docx

13 Pages
Unlock Document

University of Guelph
PSYC 2390
Lana Trick

PSYC2390CH 1 THE PERCEPTUAL PROCESSPerception does not just happenend result of complex processes Perception of worldsmall part of what is happening as you perceivePerceptual processsequence of processes that work together to determine experience of and reaction to stimuli in environment stimulus electricity and experience and actionStimuluswhat is in the environment what we pay attention to what stimulates our receptorsEnvironmentalall things in environment that we can potentially perceive Attendedchanges from moment to moment shift of attentiono On receptors image of immediate surroundings created on receptors of retina 04 mm thick network of lightsensitive receptorsother neurons lining back of eye Stimulus transformed into another formimage in retina representation Electricityelectrical signals in nervous system created by receptors and transmitted to the brain Transductiontransformation of 1 form of energy into another formIn nervous system when energy in environment ie light energy mechanical pressure chemical energy transformed into electrical energy Receptors create electrical energy in response to lightSignals activate other neurons etcsignals travel out of eye and transmitted to brainsignals dont reach the brainno perception Transmission1 neuron activates the nextNeural processinginteractions between neurons signals that originate in receptors travel through pathways between the receptors and the brain and within the brain in nervous system electrical signals representing a stimulus ie moth transmitted to receiver ie brain signal that reaches brain transformed to represent the original stimulusoriginal electrical representation of stimulus created by receptors processed into new representation of stimulusin the brain Experience and actiongoal to perceive recognize and react to stimuli Perceptionconscious sensory experienceelectrical signals that represent the stimulus are transformed by the receiver brain into experience of seeing the stimuli Recognitionability to place an object in a category that gives it meaning ie the man who mistook his wife for a hatVisual form agnosiainability to recognize objects ie caused by brain tumourActionmotor activities ie moving head or eyes locomoting through environment survival o perceptioncontinuously changing processKnowledgeinformation brought to the perceptual situation can affect steps in perceptual process Ratman demonstrationshows how recently acquired knowledge can influence perceptiono ability to categorize objectsex of howold knowledge can influence perceptual process Bottomup processingdatabased processing based on incoming data ie image on receptors starting point for perception no incoming datano perceptionTopdown processingknowledgebased processing based on knowledge past experience more complex stimuliincreased role of topdown processingo bottomup and topdown processing work together HOW TO APPROACH THE STUDY OF PERCEPTION Psychology approachGustav Fechner psychophysicsquantitative methods to measure relationships between stimuli physics and perception psycho o any measurement of relationship between stimuli and perception o psychophysical approach focuses on relationship between physical properties of stimuli and perceptual responses to stimuli Physiological approachmeasuring relationship between stimuli and physiological processes ie how different coloured lights result in electrical activity generated in neurons in a cats cortex and between physiological processes and perception ie persons brain activity measured as they describe colour of object they are seeing o studied by measuring electrical responses in nervous system can involve studying anatomy or chemical processes explain mechanisms responsible for perceptionCognitive influencesstudied by measuring how knowledge memories and expectations affect each relationship in the perceptual process o knowledge can also affect physiological responding must use both approaches to truly understand perceptionMEASURING PERCEPTION steps Describingindicating characteristics of a stimulus st Phenomenological method1 step in studying perception describes what we perceive basic properties seeking to explain Recognizingplacing a stimulus in a specific category naming ito stimulus presented observer indicates what it is from what you seeDetectingbecoming aware of a barely detectable aspect of a stimulusClassical psychophysical methodsquantitative methods for measuring relationship between stimuli and perception limits adjustment and constant stimulioriginal methods used to measure the stimulusperception relationship Absolute thresholdsmallest amount of stimulus energy necessary to detect a stimulus Methods of limitsexperimenter presents stimuli in ascending or descending orderCrossover pointchange in response perception thresholdaverage of all crossover pointsMethod of adjustmentobserver or experimenter adjusts stimulus intensity continuously until observer can barely detect the stimulus barely audible intensityabsolute threshold avg settingfaster because observers determine their threshold in just a few trials Method of constant stimuliexperimenter presents 59 stimuli with different intensities in random orderthresholdintensity that results in detection on 50 of trials most accurate method many observationsstimuli presented in random order minimizes how presentation on 1 trial can affect observers judgement of stimulus presented on next trial order effecto limits timeconsuming Difference thresholdsmallest difference between 2 stimuli that a person can detect difference between standard and comparison weights when observer first says differentFechners methods participants asked to indicate whether they detect a difference between 2 stimuliWeber small difference between standard and comparison weightsdifficult for observers to detect difference easily detect large differences Size of difference thresholddepends on size of standard weight as magnitude of stimulus increases so does size of difference threshold
More Less

Related notes for PSYC 2390

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.