Cognitive Processes PSY 334

1. Cognitive ProcessesPSY 334 Chapter 1 – The Science of Cognition

2. Study Aids • On the course web page: • Copies of these Powerpoint slides. • Textbook publisher student website: • http://bcs.worthpublishers.com/anderson7e/ • See pg 5, Chapter 1: How to study effectively (PQ4R Method). • Pay special attention to the summary statements highlighted between lines in the textbook.

3. Early History • Empiricism vs nativism (nurture vs nature) • Famous empiricists (nurture): • Berkeley, Locke, Hume, Mill • Famous nativists (nature): • Descartes, Kant • Lots of philosophical speculation but no use of the scientific method to answer questions.

4. Locke’s “Essay Concerning Human Understanding” • This work was the beginning of British Empiricism. • Locke sought a set of laws for the human mind, like Newton’s principles of physics. • Locke’s system is atomistic and reductionistic. • Basic elements of mind are ideas. • Ideas come from experience (Locke rejected Descartes). • The “blank slate, page of paper, tablet” comes from Aristotle, but characterized empiricism. • Ideas have two sources: sensation & reflection.

5. Locke & Ideas (Cont.) • Sensations can be illusory or misleading. • Ideas are either simple or complex. Simples ideas form a complex idea in several ways: • By combining several simple ideas into a single one. • By seeing the relation between two simple ideas. • By separating simple ideas from other ideas that go with them – the process of abstraction. • Locke’s idea about combination of ideas is analogous to a chemical compound (from Boyle).

6. George Berkeley (1685-1753) • Wrote three essays that radically extended Locke’s philosophy into subject idealism (immaterialism). • Berkeley argued that because all knowledge of the world comes from experience, the very existence of the external world depends on perception. • Matter exists because it is perceived – matter does not exist without a mind. • The permanence of the world is thus proof of God’s existence. • His book on vision was better regarded in his time.

7. David Hume (1711-1776) • Hume studied “pneumatic philosophy” (the name for the science of mental life). • People are part of nature so should be studied using the methods of studying nature. • He differentiated between impressions & ideas: • When impressions & ideas occur together they become associated with each other. • 3 kinds of associations: resemblance, contiguity in time or space, cause-and-effect relationship.

8. Rene Descartes

9. Ideas about the Ideas & Passions • Two major classes of ideas exist in the mind: • Innate ideas – inborn, time, space, motion, God. • Derived ideas – arising from experience, based on memories of past events (open pores stay open). • Passions arise from the body and cause actions. • 6 primary passions (wonder, love, hate, desire, joy, sadness) – other passions are mixtures of these. • Animals do not possess minds so cannot think, be self-aware or have language – have no feelings.

10. Immanuel Kant (1724-1804) • The leading German epistemologist, Kant was a subjectivist, nativist, rationalist successor to Descartes and Leibniz. • Kant wrote “A Critique of Pure Reason” saying that empiricists forgot to ask how experience is possible. • Certain intuitions or categories of understanding are inborn and frame our experiences. • This knowledge is a priori, whereas experiential knowledge is a posteriori (known afterward). • 3 categories of mind: cognition, affection, conation.

11. Kant’s View of A Priori Knowledge • Concepts of space and time. • Other intuitions, including cause and effect, reciprocity, reality, existence and necessity. • Higher faculties of reasoning are understanding, judgment, reason. • True science must begin with concepts established a priori by reason alone and deal with observable objects that can be located in time and space. • Psychology lacks this so it cannot be a science.

12. Scientific Psychology • Scientific study began in 1879: • Structuralism – Wundt, Titchener and systematic, analytic introspection. • Functionalism -- William James’ armchair introspection. • Behaviorism (1920): • Thorndike – consciousness as excess baggage. • Watson – consciousness as superstition.

13. Early Mentalists • Gestalt psychologists (German): • Wertheimer, Koffka, Kohler • Critics of behaviorism: • Tolman • European psychologists: • Bartlett – early memory researcher • Luria • Piaget

14. Mind for Behaviorists Input: Sensation Output: Behavior What laws describe the relationship between input and output?

15. Mind for Cognitive Theorists Mental Representations: Goals, Expectations, Cognitive Maps Processes Input: Sensation Output: Behavior What happens inside the “box” to produce the observed behavior?

16. Three Important Influences • Human performance studies in WWII – information needed to train military. • Artificial intelligence – thinking about how machines accomplish things leads to more analytical thinking about how humans do. • Linguistics – behaviorist principles could not account for the complexities of language use.

17. Pioneers of Cognitive Psychology • Information theory • Donald Broadbent • Artificial Intelligence • Newell & Simon • Linguistics • Chomsky – new ways of analyzing language • Miller -- psycholinguistics • Neisser’s book “Cognitive Psychology”

18. Cognitive Science • Cognitive psychology -- human thinking. • Cognitive science studies both human and machine thinking (artificial intelligence). • Cognitive science includes philosophy and neuroscience as well as psychology. • Non-human (artificial) intelligence: • http://alice.pandorabots.com/ • http://www.fil.ion.ucl.ac.uk/~asaygin/tt/ttest.html#talktothem

19. Information Processing • The dominant paradigm (approach) today in cognitive psychology. • A computer metaphor is used to conceptualize mental activity: • Mental processes operate upon mental representations • “Ops on Reps” • Flowcharted steps

20. A Functional Approach • Mental activity is described in functional terms. • Brain location, brain processes and neural representation are ignored.

21. How are Models Tested? • Because no direct observation of mental processes is possible, behavior is studied. • Measurement of response time is used to deduce the steps performed.

22. Sternberg’s Paradigm: 3 9 7 Was “9” a part of this number? 9 would be a positive probe (target) 6 would be a negative probe (foil)

23. Sternberg’s Flowchart (Model)

24. Possibilities • People look at the numbers one at a time in sequence, stopping when they get the answer. • People look at the numbers one at a time in sequence but continue until the end before giving a response. • People look at all three of the numbers at once, responding when they recognize the target number in the set.

25. What do people do?

26. If people looked at a set as a single object, the data would be different. Foil and target times would be different if people stopped searching when they found the correct answer.

27. Concerns about Cognitive Models • Relevance – do lab-task processes operate in the same manner in real life? • Sufficiency – can simple theories explain complex processes? • Cognitive architectures, computer models • Necessity – does the mind actually work as described by specific theories? • Cognitive neuroscience

28. Cognitive Neuroscience • Pages 12-30 review basic concepts about the brain. • If you have not taken PSY 210 and find this material confusing, come see me. • New methods permit study of normal human functioning in more complex tasks: • EEG • Imaging techniques – PET & fMRI

29. Review brain regions and localization of function in the brain.

30. Parts of Neuron

31. Kinds of Neurons

32. Action Potential Demo • http://outreach.mcb.harvard.edu/animations/actionpotential.swf

33. EEG measures patterns of brain activity.

34. Functional MRI (fMRI) An fMRI scan showing regions of activation in orange, including the primary visual cortex (V1, BA17).

35. Autism Affects Semantic Processing of Abstract Words

36. Using FMRI to Confirm a Model • BOLD – Blood Oxygen Level Dependent response • Measured in 3 different areas of brain: motor, parietal region, prefrontal region. • Measured and plotted every 1.2 sec. • Peaks in BOLD graph show when an area of the brain was active (4-5 sec delay). • Different components to a task can be independently tracked.

37. The Task Step 0 Step 1 Step 2

38. Measured in Three Areas Motor Prefrontal Parietal Notice that the peaks of activity for each step occur in the same order as the steps do when solving the problem.

39. Other Approaches to Cognitive Psychology • Connectionism (neural net models) – can higher level functions be accomplished by connected neurons? • Parallel distributed processing (PDP) -- Rumelhart & McClelland • Situated cognition – the ecological approach • Gibson’s affordances • Do we explain cognition in terms of the external world or internal mind?