PSYCHOLOGY1 perception

• Define perception

  the organisation and interpretation of sensory infomation
• Define sensation


  information arriving from a stimulus
• Define height in plane

  objects that are higher up in the visual field appear further away
• Define relative size

  smaller objects appear further away
• Define occlusion


  objects that hide or are infront of others appear closer to us
• Define linear perspective


  parallel lines appear to meet at a point in the distance
• define visual illusion


  a visual perception which is wrong or misinterpreted to what it actually is
• Define size constancy


  brains ability to perceive an object as being the same size regardless of whether it is close or far away
• Define ambiguity


  some stimuli can be percieved in more than 1 way
• Define misinterpreted depth cues

  brain percieves parrallel lines as different distance
• Define fiction


  a figure is percieved even though it isnt part of the stimuli presented
• Define nature


  aspects of behaviour that is inherited and innate
• Define direct theory


  what we percieve is a direct representation of the world around us
• Define nurture


  Behaviour is learned and not biological
• Describe Gibsons Direct Theory Of Perception

  suggest perception is sensation. what we percieve is a direct representation of the world around us and we are presented with enough information to make sence without making inferences
• Define inferences


  process of coming to a conclusion by filling in gaps using information from patterns
• Define perceptional hypothesis


  when the inference we make is the most probable explanation
• Define mistaken hypothesis


  when the inference we make is not the correct explanation
• Define visual cues


  help us percieve things like depth, distance and size of objects
• Strength of Gibson's Direct Theory Of Perception


  supports theory of perception because the infants studied are young so could not have learnt depth perception through experience, instead are born with an awareness of perception
• weakness of Gibson's theory of perception


  Struggles the explain visual illusions because they are examples of perceptional errors, where our brain comes to an incorrect conclusion of what we see
• Describe Gregorys Constructivist Theory


  Suggests perception is influenced by nurture and uses past experiences to form a model of reality, we have to use inferences
• Strength of Gregory's theory


  there are many studies that have found people in different parts of the world may interpret visual cues differently- this shows different experiences alter our perception
• Weakness of Gregory's theory

  Babies have been shown to be able to percieve the world with little to none experiences. they cannot have relied on stored knowledge as they do not have any stored
• Define culture


  a group of people who share similar customs, beliefs and behaviours
• Aim of Bruner and Minturn's study


  aim was to investigate how expectations can direct perception
• What was the research method for Bruner and Minturn?

  Laboratory experiment
• Method of Bruner and Minturn's study

  24 students participated. letters or numbers were flashed up quickly (30ms) and increased by 20ms each time. asked to draw letter/number as soon as they recognised it. half the students were shown 4 stimulus letters followed by numbers then a test timulus (broken B) each saw test stimulus 3 times. other group followed same procedure but counterbalanced
• Results of Bruner and Minturn's study

  Those who saw a sequence of letters were more likely to report the figure as being the letter B. If shown numbers they were more likely to say it was the number 13 and drew a '13'.
• Conclusion of Bruner and Minturn's study


  researchers concluded that the participants expectations had directly affected how they interpreted the stimulus figure.
• Strength of Bruner and Minturn's study

  high reliability because the laboratory setting meant it could be replicated for consistent results. Environment was controlled so there were no extraneous variables
• Weakness of Bruner and Minturn's study

  1. lacks ecological validity- difficult to test the effect of expectation on perception in real life settings as it is unpredictable

  2. cannot be generalised- study is ethnocentric, values one culture above another. doesnt consider cultural bias which could alter results
• Define expectations


  a belief about what is likely to happen based on past experience
• Define perceptional constancy


  ability of the brains perceptual system to make allowences for change in the environment
• Aim of Gilchrist and Nesburg study


  To find the affect that food deprivation would have on the perception of food related images
• Method of Gilchrist and Nesberg's study

  26 undergrads. Two groups of students: one group deprived of food for 20 hours and a control group. Students were shown four slides, each one showing a meal for 15 seconds.

  The picture was shown dimmer, and participants had to adjust the lighting to make it look the same as it did before.
• Results of Gilchrist and Nesburg study


  Food deprived participants were shown to have perceived picture as brighter than it originally was.
• Conclusion of Gilchrist and Nesburg's study

  suggests hunger is a motivating factor that affects perception. when deprived, sences are heightened making things appear more appealing.
• Strength of Gilchrist and Nesberg's study

  high ecological validity because participants actually were food deprived, study was carefully controlled in a laboratory setting. both groups had same conditions and timings so would be easy to replicate
• Weaknesses of Gilchrist and Nesberg's study

  1. cant be generalised all participants were same age and health requirements.

  2. low mundane realism, not a regular occurrence to be asked to fast then readjust an image.

  3. potential ethical issues, could not eat for 20hours, could have been vulnerable to complications