Cognitive Psychology

Chapter 1: Introduction to Cognitive Psychology Cognitive psycgology is the branch of psychology concerned with the scientific study of the mind. Studying the mind Donder’s experiment: How long does it take to make a decision? He wanted to measure the reaction time, two measures; simple reaction time (press a button when you see a light), choice reaction time (press a button when they saw the left light go on, and another button when the right went on). As expected, the reaction time for choice was longer than simple. Donders reasoned that the difference in reaction time between these would indicate how long it took participants to make the decision that led to pushing the correct button. Because in this example the choice took around 100 milliseconds longer than the somple, it could therefore be concluded that the decision-making process took around 100 ms. The experience is important because it shows that mental responses (perceiving the light and deciding which button to push) cannot be measured directly, but must be inferred from behavior. This holds for all researchers in cognitive psychology. Wundt’s psychology laboratory: Structuralism and analytic introspection. His approach was called structuralism; our overall experience is determined by combining basic elements of experience which were called sensation. Wundt wanted to create a “periodic table of the mind”. He thought he could achieve this scientific description of the components of experience by using analytic introspection; where trained participants describe their sensations, feelings and thought process in response to stimuli. Woundt is seen as leading the shift in the study of the mind from the rationalist approach to the empiricist approach. Ebbinghaus’ memory experiment: What is the time course of forgetting? How rapidly information that is learned is lost over time. He used a quantitative method for measuring memory using himself as the participant. He repeated lists of nonsense syllables such as, DAX, QEH, LUH and ZIF to himself one at a time at a constant rate. He did not want his memory to be influenced by the meaning of a word - therefore the nonsense. He proposed a measure called savings to determine how much information was retained after a particular delay Savings = (original time to learn the list) - (time to re-learn the list after the delay). Longer delays result in smaller savings, due to longer to re-learn. The saving curve shows that memory drops rapidly for the first two days after the initial learning and the levels off. This curve is important because it demonstrated that memory could be quantified and that functions like the savings curve could be described as a property of the mind - in this case, the ability to retain information. 0 William James’ Principles of Psychology: Famous book principles of psychology. He observed the opservation of his own mind. The nature of the mind: Millions of items … are presented to my senses which never properly enter my experience. Why? Because they have no interest for me. My experience is what I agree to attend to … Everyone knows what attention is. It is the taking possession by the mind, in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought … It implies withdrawal from some things in order to deal effectively with others. True today - still valid Behaviourism Watson founds behaviourism: Watson became dissatisfied with the methods because 1) produced variable results from person to person, 2) these results were difficult to verify. Watson proposed a new approach called behaviorism: Psychology as the behaviourist sees it is a purely objective, experimental branch of natural science. Its theoretical goal is the prediction and control of behaviour. Introspection forms no essential part of its method, nor the scientific value of its data dependent upon the readiness with which they lend themselves to interpretation in terms of consciousness, the objective point of our attack. Keypoint; 1) watson rejects introspection as a method, 2) observable behavior, not consciousness (which involve unobservable processes such as thinking etc) is the main topic of study. Watsons idea is closely associated with classical conditioning. Experiment from Pavlov; dogs could be made to salivate to the sound of a bell, paired with food. Watson showed that the same principle applied to humans.