Perception Flashcards
What are the two binocular depth cues?
Retinal disparity:
Difference between the view of the left and right eye gives brain information about depth and distance.
Convergence:
Eyes point closer together when an object is close.
Muscles work harder so know distance and depth.
What are the four monocular depth cues?
Height in plane:
Objects higher up appear further away.
Relative size:
Smaller objects appear further away.
Occlusion:
If one object obscures part of another object, it is seen as closer.
Linear perspective:
Parallel lines appear closer as they become more distant
Describe Gregory’s constructivist theory of perception.
Contrasts with Gibson’s theory.
Proposes that sensation and perception are not the same.
Perception as a construction:
Brain uses incoming information and information we already know to form a hypothesis/guess.
Inference:
Brain fills in the gaps to create a conclusion about what is being seen.
Visual cues:
Visual illusions occur because of incorrect conclusions from visual cues.
Past experience - the role of nurture:
Perception is learned from experience.
The more we interact the more sophisticated our perception.
Evaluate Gregory’s constructivist theory of perception.
Support from research in different cultures:
People interpret visual cues differently (e.g. Hudson’s study), showing experience affects perception.
Visual illusions
Gregory’s research used 2D visual illusions which are artificial, so theory may not apply to the real world.
How does perception get going?
Babies have some perceptual abilities (Fantz) so perception can’t be just the result of upbringing.
Describe a study on motivation.
Wanting something increases its attractiveness.
Gilchrist and Nesberg’s study:
Aim:
To find out if food deprivation affects the perception of food.
Method
Hungry (no food for 20 hours) and not hungry participants shown a slide of a meal.
Had to adjust light to level of slide shown.
Results
Perceived food as brighter the longer deprived of food.
Conclusion
Sensitivity greater when food deprived.
Hunger is a motivating factor that affects perception of food.
Evaluate a study on motivation.
Gilchrest and Nesburg:
Support from similar studies:
Sanford’s study found similar results which strengthens the validity of the conclusions.
Ethical issues:
Depriving people of food causes discomfort, a case of physical harm.
Not like everyday life:
Participants judged pictures rather than real food so it may not apply to real world.
Describe a study on expectation:
Beliefs based on past experiences can affect how much we attend to things.
Bruner and Minturn’s study:
Aim
To find out if an ambiguous figure is seen differently if context is changed.
Method:
Participants shown a sequence of letters or numbers with an ambiguous figure in the middle.
Results:
Those who saw letters said B.
Those who saw numbers said 13.
Conclusion:
Shows expectation is affected by the context the figure is presented.
Evaluate a study on expectation.
Artificial task:
Ambiguous figures are designed to trick perception, so task lacks validity.
Independent groups design:
Participant variables may have caused the difference in results not expectation.
Real-world application:
The study can explain the sometimes serious mistakes people make in the real world.