PSYC 441 Cognitive Psychology II

Transcription

1 PSYC 441 Cognitive Psychology II Session 3 Paradigms and Research Methods in Cognitive Psychology Lecturer: Dr. Benjamin Amponsah, Dept., of Psychology, UG, Legon Contact Information: bamponsah@ug.edu.gh College of Education School of Continuing and Distance Education 2014/ /2017

2 Session Overview This session will focus on the various frameworks used by cognitive psychologists in planning and executing their research. These are referred to as paradigms and we shall discuss four of such paradigms. We shall also discuss the major research methodologies used to study cognitive psychology. The choice of a particular method is determined largely by the logic of the method in answering the research questions and to smaller extent, the type of data generated. Slide 2

3 Session Objectives At the end of the session, the student will be able to List and discuss the paradigms used in the study of cognition Discuss the focus of each paradigm in detail Describe the methods used to conduct cognitive psychological research. Slide 3

4 Session Outline The key topics to be covered in the session are as follows: Topic One: Information Processing Paradigm Topic Two: Parallel-Distributed Processing Paradigm Topic Three: Ecological and Evolutionary Approaches Topic Four: Research Methods in Cognitive Psychology Naturalistic Observations, Introspection, clinical Interviews, Experiments and Quasi-experiments, Neuropsychological Investigations Slide 4

5 Reading List Ashcraft, M. H. (2013). Cognition (6 th edn.), London: Pearson Education Int. Eysenck, M. W. (2012). Fundamentals of Cognition (2ed). Psychology Press, Sussex. Galotti, K. M. (2017). Cognitive Psychology: In and out of the laboratory (6 th edn.). Belmont, CA: Wadsworth. Halpern, D. F. (2013). Sex differences in cognitive abilities (2ed). Lawrence Erlbaum Ass. NJ. Hunt, R. R. & Ellis, H. C. (2004). Fundamentals of Cognitive Psychology (7 th edn.), New York: McGraw-Hill. Willingham, D, B. (2013). Cognition: The thinking animal (International edn. NJ: Prentice-Hall). Slide 5

6 Topic One INFORMATION PROCESSING PARADIGM Slide 6

7 We now focus on the frameworks used by cognitive psychologists in planning and executing their research. What is a paradigm? First, a paradigm may be thought of as a body of knowledge structured according to what its proponents consider important and what they do not. Secondly, paradigms also include all the assumptions that researchers make in studying a phenomenon of interest. Slide 7

8 Thirdly, paradigms also specify the kinds of experimental methods and measures that are considered appropriate to use in an investigation. We may consider paradigms as intellectual frameworks that guide investigators in studying, understanding and explaining phenomena. Slide 8

9 Information Processing Paradigm The information processing approach is the most popular paradigm used in the study of cognition and it has dominated cognitive psychology since the 1960s and 1970s. The approach draws on analogy between human cognition and computerized processing of information. The popularity of this approach is also directly related to the development known as computer metaphor. According to the computational metaphor, our cognitive processes work like a computer a complex, multipurpose machine that processes information quickly and accurately. Slide 9

10 In Information Processing, Cognition can be considered as information (information represents - what we see, hear, read about, think about) passing through a system (our minds). The information is processed (meaning information is received, stored, recoded, transformed, retrieved and transmitted) in stages and it s stored in specific places while it is being processed. Slide 10

11 TYPICAL INFORMATION PROCESSING MODEL

12 One important limitation of the informationprocessing approach is that it doesn t adequately explain how several stimuli are processed and retrieved at the same time. Slide 12

13 Topic Two PARALLEL-DISTRIBUTED PROCESSING Slide 13

14 This is an attempt to explore alternatives to the information-processing approach in the early 1980s. One outcome is development of the framework known as the Parallel-Distributed Processing (sometimes called Connectionist model). Its name is derived from models which depict cognition as a network of connections among simple but numerous processing units. Because these units are sometimes compared to neurons (the cells that transmit electrical impulses), they are sometimes called neural networks. Slide 14

15 Each unit is connected to other units in a large network. Each unit (node) has a level of activation at any particular moment in time. Slide 15

16 Parallel Distributed Processing

17 Important Notes on the Connectionist Model The units in the centre are sometimes called nodes (a point in a network upon which a number of operations impinge). Each node depicts a certain individual and each unit is connected to other units that depict certain information about individuals e.g., names, cars, professions etc. The arrows between units depict excitatory or positively weighted connections. When a unit reaches a certain level of activation, it activates all the other units to which it has positively weighted connections. Slide 17

18 Comparisons b/n Information-Processing Model and PDP With information-processing, cognition is assumed to occur serially in discrete stages (one after the other). In contrast, connectionist models assume parallel processing (many at the same time). For the parallel-distributed processing, learning occurs when new connective patterns are established that change the weights of connections between units. In contrast, the information processing approach assumes permanent change in behaviour and consolidation in the memory systems, especially in the LTM. Slide 18

19 Topic Three ECOLOGICAL AND EVOLUTIONARY PARADIGMS Slide 19

20 Ecological Paradigm The third major approach comes from both psychologists and anthropologists and their beliefs in many ways are at variance with those in info-processing and the connectionist views. The idea is that cognition does not occur in isolation from larger cultural context. All cognitive activities are shaped by the culture and the context in which they occur. Culture forms the bedrock of our cognition and influences the ways in which cognitive activities are acquired, practised and executed. This approach was largely influenced by the functionalist school, in that they were more concerned about the purpose or function served by a given cognitive process. Slide 20

21 The approach was influenced by the Gestalt school, because the approach emphasises the context surrounding any experience. This tradition relies less on laboratory or computer simulations and more on natural observation and field studies to explore cognition. The basic aim of the ecological approach is to look at function of particular cognitive activity. Slide 21

22 Evolutionary Paradigm Evolutionary psychologists believe that we understand a system best if we understand the evolutionary pressures on our ancestors. The theory emphasises development of cognitive skills or abilities through interaction of culture and evolutionary process shaped by natural selection (survival of the fitters). Human mind is a biological system that is assumed to have evolved over several generations and subject to the laws of natural selection. Therefore due to evolutionary pressures, humans adapted in certain ways in response to the environment encountered by our predecessors. Slide 22

23 Example. In spatial cognition, males perform better than females. How is this spatial skill difference explained by evolutionary psychologists? According to Geary (1995), spatial sex differences occurred for two reasons. First, Intramale Competition (e.g., polygamy, hunting, warfare) was a source of sex differences in spatial ability. Males had to travel far to ambush and capture other males and mate their wives leading to the survival of the offspring of skilled rather than the less skilled hunters. Slide 23

24 Second, the greater mobility of males created greater selection pressures for navigational skills. (e.g., timing and hitting targets, orientation to objects, skills need for habitat navigation and understanding of geometric shapes among objects). Women were virtually excluded from all these activities and that led to spatial skill development in males more than females. Interesting, but the theory has been criticised as speculative (the theory doesn t take into account modern technological developments that do not require specializations based on sex categories). Slide 24

25 Topic Three RESEARCH METHODS IN COGNITIVE PSYCHOLOGY Slide 25

26 We now discuss the major methodological approaches to cognitive psychology. Have in mind that the choice of a particular choice is determined largely by the logic of the method in answering the research questions and the type of data generated. Naturalistic Observation Naturalistic observation involves the researcher watching people in familiar, everyday contexts who are going about their cognitive activities. For example, an investigator might watch people as they try to figure out how to operate a new automated teller machine (ATM) at the Bank. Usually, the observer tries to remain as unobtrusive as possible. Slide 26

27 Observational studies have the advantage that the things studied really do occur in the real world and not just in an experimental laboratory or a laboratory curiosity. One important property of these studies is called ecological validity the principle that the research must resemble the situations and task demands that are characteristic of the real world rather than rely on artificial laboratory. In observational studies therefore, the observer has the chance to see just how cognitive processes work in natural settings and how they are affected by environmental changes. Slide 27

28 There are several disadvantages with this method. One disadvantage is lack of experimental control. That is, the observer has no means of isolating the causes of different behaviors or reactions. All he does is to try to collect observations and tries to discover relationships among variables The observer has no way of verifying plausible different hypothesis. Another problem in this method is that the observer s recordings are as good as his initial plan of what he wants to record. Another question is how can one know what people would have done had they not been observed. Slide 28

29 Introspection This special observation dates back to the laboratory of Wundt father of psychology. With this method, the observer observes his own mental processes. For example, participants may be asked to solve complicated mathematical problems without paper or pencil and to think aloud as they do so. One benefit of this method is that observing one s own reactions and behaviour might give one better insight into an experience and the factors that influenced, providing a richer, more complete picture than an outsider could observe. But observing yourself is a double-edged sword, since it has the tendency for you to be biased in regard to your own cognition. Slide 29

30 People observing their own mental processes may be concerned with their level of performance and may be motivated to distort their observations to make them feel good or credible Furthermore, in some cognitive tasks (demanding ones) observers may have few resources left with which to observe and record. Slide 30

31 Controlled Observation and Clinical Interviews With this method, the researcher may have some influence over the setting in which observations are conducted. Researchers using this research method try to standardize the setting for all participants or manipulating specific conditions to see how the participant will be affected. For example in using the ATM example, the researcher may arrange for the ATM to display different instructions to different people. Such a study would still be observational because the researcher cannot control who will use the machine when and how. Slide 31

32 Clinical Interviews Clinical Interviews In this research, the investigator asks each participant a series of open-ended questions. That is, the investigator directs the questions in contrast with the free method used in introspection. In clinical interviews, the follow-up questions from the researcher depend on the responses from the respondent. This helps the researcher to follow the line of thinking of the participant. Slide 32

33 Experiments and Quasi-experiments Experiments and Quasi-experiments One important distinction between experiments and observational methods is the investigator s degree of experimental control. Having control means that the experimenter can assign participants to different experimental conditions at random so as to minimize pre-existing differences between them. True Experiments In conducting a true experiment, the experimenter manipulates one or more independent variables (the experimental conditions) and observes how the recorded measures (dependent variables) change as a result of the manipulation. Some independent variables preclude random assignment. Slide 33

34 Experiments and Quasi-experiments are useful because they allow researchers to isolate causal factors and make better-supported claims about cause and effect relationships than when they use observational methods. One serious drawback of the experimental method is that it fails to fully capture real-world phenomena in the experimental task or research design. The extent to which we can generalize from experimental research is therefore limited. Slide 34

35 Neuropsychological Investigations Much of the work done in neuropsychology involves examining the brains of people. Cognitive neuropsychology is the study of cognitive deficits in certain brain-damaged individuals. Before the latter half of the last century, this kind of examination could be conducted only after a patient died, during an autopsy. Slide 35

36 This has dramatically changed since the 1970s, and various techniques of brain imaging have been developed to construct pictures of the anatomy and functioning of intact brains. For example, X-ray computed tomography (X-ray CT), Magnetic Resonance Imaging (MRI), Computerized axial tomography scans (CAT Scans) are used to scan brain structures. The CAT for example can be used to pinpoint areas of brain damage and make inferences about the relative duration of the injury. Slide 36

37 There is yet another method used to detect different state of consciousness and that is the Electroencephalography (EEG). Researchers or clinicians use this technique to measure electrical activities of the brain for example, brain activity like wakefulness, drowsiness, coma etc). While former provide information about neuroanatomy, the latter (electroencephalography) provide information about brain activity. Slide 37

38 Cognitive neuropsychologists use these techniques to identify individuals with certain patterns of brain damage and examine their cognitive performance. For example, what cognitive processes can these individuals no longer perform? What activities are spared? By finding answers to these, some individuals may be helped and also help us to understand how our cognitive works. Slide 38

39 Sample Questions Compare and contrast the four major paradigms of cognitive psychology discussed in this section. Evaluate the speculations offered by evolutionary psychologists in explaining cognition. Compare and contrast the various research methods used by cognitive psychologists in conducting research. Slide 39

40 References Geary, D. C. (1995). Sexual selection and sex differences in spatial cognition. Learning and Individual Differences, 4, Slide 40

41 THANK YOU Slide 41