Pd1 Is perception learned one aspect of the nature nurture question Empiricists say that everything is learned even perceptual abilities Locke Hume At birth we are a tabula rasa blank sheet to be filled by experience Rationalists Kant argue that perception is innate Pd2 Infant experiments Logic if you can do it at birth or hatching prior to any How to test experience it must be innate Depth perception visual cliff chicks goats Face perception humans Voice perception humans Innate tendency to look at faces and listen to voices results in predisposition to learn about these These results show that innate knowledge often consists of an interest in and a tendency to learn a particular kind of thing Deprivation experiments restricted experience Pd3 How to test contin Deprivation experiments restricted experience Logic if you can do it when deprived of relevant experience it must be innate If you cannot do the task we cannot conclude anything Cataract patients deprived of form vision since birth after surgery they can tell figure from ground but not discriminate forms Pd4 How to test contin Deprivation experiments contin Wiesel and Hubel s experiments on kittens A critical period for developing binocular vision Preventing early binocular experience e g by covering one eye during first few months of life can prevent development of stereoscopic depth perception A critical period for orientation acuity Pd5 Orientation selective neurons in normal adult cat Neurons with all different orientations are found Pd6 Raise kitten in Horizontal environment Pd7 Orientation selective neurons of adult cat raised in a horizontal environment Neurons with vertical orientation selectivity are lost Behavior also changes navigation through horizontal and vertical environment Pd8 How do findings in kittens relate to angular acuity in humans Horizontal and vertical angular acuity is better than oblique Is this due to our experience