PSY504 Official Handouts

Contents · Cognitive Neuropsychology I · Cognitive Neuropsychology II · Visual sensory memory experiments I · Visual sensory memory experiments II · Attention · Automaticity · Pattern recognition

Pattern recognition: Feature analysis Pattern recognition: Gestalt theory of perception

Object perception

Attention & pattern recognition

Pattern recognition: Neural networks Pattern recognition: Effects of sentence context Memory: STM Memory: chunking Memory: The Nature of Forgetting

Memory: Long Term

Memory: Interference Memory: Recall Vs Recognition Memory: Forgotten Memories Exist Memory: Representation of Knowledge Memory: Representation of Knowledge, Schema Theory Memory: Representation of Knowledge (Memory for Stories) Memory: Representation of Knowledge (Application for Studying)

Mental Imagery · Eidetic imagery · Language and thought · Cognitive development · Lesson 01

Cognitive Psychology deals with cognition. Cognition can be understood as “thinking” or “knowing.” We can say, in other words, that cognitive psychology deals with the processes involved in thinking, acquisition and storage of knowledge. For this purpose it adopts an information processing approach.

Historical Background

Plato, the great Greek philosopher, was the first person to present a coherent theory of how knowledge is acquired and retained. He proposed that ideas are created in the human mind and that these ideas are then projected out in the world. These projections serve as images that we see through our senses. In other words, the outside world is an illusion made up of projections of ideas and the true reality lies inside of us. Therefore, Plato concluded that perception is an internal process and we can learn everything by looking inwards. When psychology was first taught in European universities, it was subsumed under the title of mental philosophy. Philosophers throughout the history have been concerned with concepts of perception and knowledge, as to how these interact with reality. Similarly the field of epistemology within philosophy has been concerned with the nature of knowledge. Thus cognitive psychology has been present as an undercurrent in the field of ontology and epistemology throughout the last two millennia. More recently, in 1875 Wilhelm Wundt set up the first psychological laboratory to study perception and cognition. A lot of the perceptual experiments and studies conducted were included in the field he called psychophysics. An example of psychophysics is the relationship of sensation and intensity of the stimulus. A major problem with most psychological studies of this time was over-reliance on introspective reports. In these reports, information was acquired by asking subjects what they felt, thought or saw, heard etc. and these reports were then used for deriving psychological principles. This was around the same time that Freud proposed the idea of unconscious processing. We now know for sure that most cognitive processing takes place at an unconscious level. The criticism of the introspective technique soon led psychology to its opposite extreme and the behaviorist school took over. The behaviorists argued that anything that we could not observe could not form part of the science of psychology. They coined and exclusively used terms like stimulus, response, reinforcement, conditioning etc. All of these had to do with phenomena that could be converted into some kind of numerical representation. Hunger, for example, was called “number of hours of food deprivation.” Behaviorists relied only on things that could see and rejected phenomena such as memory and imagery as unscientific just because they couldn’t think of a way of observing and measuring them. During the 2nd world war, human factors research and information theory combined to generate the information processing approach. This approach along with several other factors led to the creation of a new field called cognitive psychology. Among these factors was Noam Chomsky’s critique of Skinner’s book Verbal Behavior. Chomsky in his groundbreaking paper “On verbal behavior” shattered the simple minded behaviorist model of language designed by Skinner. He argued that language was far too complex to be explained by stimulus response alone. Around the same time, computers had emerged as thinking machines, where a lot of similarities with human information processing were coming to the fore. The field o artificial intelligence had also emerged which sought to make computers that thought like humans and solved problems and learned new things. Donald Broadbent was working at the same time on attention and visual perception. A lot of experimental work during that time along with Bartlett’s classic experiments on memory combined to create what Ulric Neisser called Cognitive Psychology in a book entitled “Cognitive Psychology.