1 Chapter 10 Introduction Visual Imagery Definition Mental Imagery Definition Seeing with the absence of a visual stimulus The ability to recreate the sensory world in the absence of physical stimuli also occurs in other sense than vision Examples 1 Paul Mccartney with one of his songs 2 Albert Einstein traveling a light ray 3 Jack Nicklaus with changing in grip 4 Friedrich Kekule with the structure of a benzene Imagery in the History of Psychology Early Ideas about Imagery Wilhelm Wundt He proposed that imagery is one of the 3 basic elements to consciousness along with sensation and feeling The idea between image and thinking gave rise to the Imageless Thought Debate thoughts are impossible without an image Aristotle Evidence Francis Galton Observation of people who had great difficulty forming visual imagery were still capable of thinking normally Behaviorism This shift in the field killed the debate and said it was impossible to study therefore had no need to study it Imagery and the Cognitive Revolution This lead to the study of inferring cognitive processes Examples Alan Paivio He did work on memory He showed that it is easier to remember concrete words like truck and tree rather than abstract words like truth or justice He used paired associate learning Interpretation Memory for concrete words are better because of The Conceptual Peg Hypothesis Concrete words create images that other words can latch on to 2 Roger Shepard and J Metzler They studied Mental Chronometry which is the amount of time needed to perform a cognitive task Method Results They had participants look at pictures of rotated objects and determine if it was the same object The time it took to decide that it was the same object is directly correlated to how different the angles were between the two objects Interpretation Participants were mentally rotating one of the views to see whether it matched the other object It was the first study to apply quantitative methods t study imagery and suggest that imagery and perception share the same mechanism Imagery and Perception Do They Share the Same Mechanisms Although perception and imagery are not analogous in every aspect Shepard and Metzler s results show that they both involve spatial representation of the stimulus Stephen Kosslyn Did a study using Mental Scanning Mental Scanning Definition People create mental images then scan them in there mind Experiment 1 He asked people to memorize a picture of an object Ex A Boat And asked them to focus on one part of the boat like the anchor then asked to press a button when they found another part of the boat or press a button if they couldn t mentally locate it If imagery is like perception it should take longer long for participants to find the objects that are farther than the initial point of focus It did take longer for them to find objects that were farther from the initial starting point thus imagery is similar to perception He proposed that it took longer for them to reach farther objects because other interesting parts could have distracted them along the way this making it take longer Results G Lea Experiment 2 Kosslyn He had people image a island and it again showed that distance matters not distractions Zenon Pylyshyn 3 He proposed another explanation called the Imagery Debate Imagery Debate Definition A debate about imagery is based on spatial mechanisms involving perception or mechanisms related to language like Propositional Mechanisms The Imagery Debate Is Imagery Spatial or Propositional Kosslyn Spatial Imagery A representation in which different parts of an image can be described as corresponding to specific locations in space Depictive Representations Representations that are like realistic pictures that resemble an object so that part of the representation correspond to parts of the object Pylyshyn He says just because we experience it as spatial doesn t mean the underlying representation is spatial it is a epiphenomenon Epiphenomenon something that accompanies the real mechanism but is not actually part of the mechanism He proposed the idea of Propositional Representation Propositional Representation Definition Relationships can be represented by abstract symbols such as an equation or a statement like the cat is under the table Tacit Knowledge Explanation People unconsciously use knowledge about the world in making their judgements He proposed this to explain Kosslyn s boat traveling experiment Ronald Finke and Stephen Palmer They did an experiment to counter the Tacit Knowledge Explanation Method Results Showed four dots then a arrow appeared and they were asked if the arrow was pointed at any of the dots that they saw It took longer to respond if there was a greater distance between the arrow and the dots Interpretation Participants didn t have time to memorize the distance between the arrow and the dot before making their judgements it is unlikely that they used Tacit Knowledge Comparing Imagery and Perception 4 Size in the Visual Field Kosslyn When you are far from a car you cannot see details like the door handle but when closer you could He wanted to know if this is true for mental images Method He told people to image animals next to each other like an elephant and rabbit and make sure they were standing close enough the larger animal so it filled most of their visual field He then asked if a Rabbit has whiskers and asked people to look in their mental image to find the answer He repeated it but asked them to image a rabbit and a fly and asked the same question He also asked them to do a Mental Walk Task Definition Image that they were walking towards their mental image The animal Results For Questions There was faster reaction time when the rabbit was with the fly For Mental walk they walked shorter distances for smaller animals and longer distances for larger animals just as what would happen in real life Interpretation It leads us to conclude the further connection between Interactions of Imagery and Perception imagery and perception They wanted to see if imagery affects perception or perception affects imagery therefore they are connected Cheves Perky He did a experiment to test this idea Method Asked people to project their visual images onto a screen and then describe these images They didn t know that there was a back projection of a dim object Thus when participants were asked to make a mental image of a banana there was a actual banana projected onto the screen Not one of the 24