The Spirit of Mechanism

1. The Spirit of Mechanism • 17th to 19th century zeitgeist reflected in: • Amusement with mechanical figures • The universe as a enormous machine • Mechanism: all natural processes are mechanically determined

2. Physics (natural philosophy) • Galileo: matter is comprised of atoms that affect one another by direct contact • Newton: Planets moved by invisible forces, not by actual physical contact Galileo (1564-1642) Newton (1643-1747)

3. Physiology of the Nervous System • Luigi Galvani (1737-1798) • Italian Physiologist • Identified electricity as the “currency” of the nervous system • Nephew (Giovanni Aldini) continued the tradition using severed heads of criminals • More Showmanship than Science

4. Johannes Müller Doctrine of Specific Nerve Energies • The mind is directly aware not of objects in the physical world but of states of the nervous system. • “The qualities of the sensory nerves of which the mind receives knowledge in sensation are specific to the various senses, the nerve of vision being normally as insensible to sound as the nerve of audition is to light. “

5. Paul Broca (1824-1880) • The Clinical Method (1861) • Broca’s area: the speech center in the 3rd frontal convolution of the left hemisphere of the cerebral cortex

6. Mapping from the Outside • Franz Josef Gall (1758-1828) • Used the clinical method to map the brain and confirm: • Existence of white and gray matter • Fibers from each brain side to the opposite spinal column side • Fibers connecting the two brain hemispheres • “How do the size and shape of the brain reveal information about brain facilities?” • Can it be mapped from the outside?

7. Phrenology • J.G. Spurzheim (1776-1832) • Gall’s student • Took specific nerve energies a little too far

8. Pierre Flourens (1794-1867) • Prof. of Natural History-Paris • Used extirpation (ablation) • Isolate the parts • Remove, when necessary, the entire parts • Always prevent the complication of theeffects on the lesions due to the effects of effusions.

9. Physiology of the Nervous System • Camillo Golgi (1844-1926) • Italian neurologist • S. Ramón y Cajal (1852-1934) • Spanish neuroanatomist • Nobel Prize 1906

10. Hermann von Helmholtz (1821–1894) • Born in Potsdam, Germany • Delicate health • 1838: enrolled at a Berlin medical institute: free tuition to future army surgeons • Seven years in the army

11. Ernst Weber (1795 – 1878) • Born in Wittenberg, Germany • 1815: PhD at university of Leipzig • 1817 – 1871: taught anatomy and physiology at Leipzig • Primary research interest: physiology of sense organs • Applied experimental methods to problems of psychology • Explored new fields: cutaneous sensations rather than just vision and hearing

12. Ernst Weber (1795 – 1878) • Thresholds • Two-point discrimination of the skin • Predicted layout of sensory cortex

13. Gustav Theodor Fechner (1801-1887) • Born in southeastern Germany • 1817: began medical studies at University of Leipzig • Attended Weber’s lectures on physiology • Professor at Leipzig

14. By the mid 19th century natural science methods were being used to study mental phenomena • British empiricists outlined the importance of understanding the limitations of the senses • German physiologists described functioning of the senses and paved the way for Wilhelm Wundt who brought them together by founding psychology

15. Wilhelm Wundt (1832 – 1920) • Started the first laboratory and the first journal in experimental psychology • Viewed Fechner's work as the first experimental psychology

16. Leipzig Lab Gear Precision Chronograph Pulse Generator Tachistoscope

17. Other Developments in Germany • Hermann Ebbinghaus (1850-1909) • Directed clear experiments on memory (nonsense syllables) • Influenced by Fechner • Fechner – Measured senses indirectly with thresholds • Ebbinghaus – Measured memory indirectly by counting numbers of items recalled after specific periods of time

18. Ebbinghaus and Memory • Ebbinghaus’ Forgetting Curve • CVC Nonsense syllables (lef, bok) • Control for familiarity • Randomized presentation from 2,300 syllables • Compared nonsense to sense • 80 nonsense syllables • 80 syllables of Don Juan

19. Other Developments in Germany • Carl Stumpf (1848-1936) • Appointed to professorship at the University of Berlin • Wundt’s major rival • Two of his students founded Gestalt Psychology • Kurt Koffka • Wolfgang Köhler

20. Experimenter Bias & Clever Hans • Wilhelm von Osten: Animal intelligence • Oskar Pfungst (Stumpf’s student)

21. Spontaneous variability among members of a species is inheritable – He described genes and mutations without the benefit of biochemistry! • Natural selection: process that leads to survival of organisms which adapt to the environment; Elimination of those which do not

22. Edward Lee Thorndike (1874–1949) • Cats and Puzzle Boxes • Trap a cat…random behavior will evolve in to a specific behavior aimed at generating results • Consequences led to the “stamping in” or “stamping out” of responses (Trial-and-Accidental-Success-Learning)

23. Ivan Petrovitch Pavlov (1849-1936) • In general • His work helped shift of associationism from subjective ideas to objective physiological responses • Provided Watson with a new method

24. Sigmund Freud (1856-1939) Three shocks to the human ego (Freud, 1917) • Copernicus: Earth not center of universe • Darwin: Humans not a distinctive species • Freud: Unconscious forces rather than rational thought govern our lives/moods

25. John B. Watson (1878-1958) • Watsonian Behaviorism • Ultra-Scientific • Dealt solely with observable behavioral acts • Objective descriptions of the data • Rejection of mentalistic concepts and terms • Consciousness comparable to soul, introspection irrelevant

26. Skinner • Operant Conditioning (Type I) vs. Respondent Conditioning (Type II) • Skinner Box was similar to Thorndike’s Puzzle Box • The purpose of psychology is to understand individuals – single subject designs. • Behavior is the focus – no black Boxes! • Behavior is controlled by its consequences.

27. The phi phenomenon: A challenge to Wundtian Psychology • A product of Wertheimer's 1910 research • Developed riding a train while on vacation • Involved seeing movement when no actual physical motion occurs

28. Wolfgang Köhler (1887- 1967) • 1913-1920: unable to leave Canary Islands during WWI • Studies the behavior of chimpanzees • 1917: The Mentality of Apes • 1922: succeeded Stumpf at U. of Berlin • Static and Stationary Physical Gestalts (1920) Suggested Gestalt theory as general law of nature

30. War and Science

31. Artificial Intelligence Is the intelligence of the computer the same as that of the human? Initially, idea eagerly accepted 1950 Turing test: can a subject interacting with a computer be persuaded that he/she is communicating instead with a human? Chinese Room Problem Deep Blue vs. Kasparov Alan Turing (1912-1954)

33. Properties of a Hebb Synapse

34. Hodgkin and Huxley Alan Lloyd Hodgkin and Andrew Huxley explain the mathematics and chemistry in the squid giant axon in 1952 If one neuron can be explained with math, perhaps the same is true for the whole system (brain)? This discovery corresponded with advances in computer technology

35. Rosenblatt Perceptron (1958) Learned to categorize The perceptron had to be trained If it was wrong, connections were adjusted

36. The Founding of Cognitive Psychology No single founder George Miller: Seven +/- 2 The computer and brain Both electric Process information in stages Software can be modified (like synapses)

37. Darwin’s Theory Variations in traits are the norm They are inherited (through genes) New variations appear spontaneously (genes mutate) Changes in the environment will put selective pressures on these traits. Some will survive, some won’t

38. Some Sociologists Did Not Looking for Utopia Margaret Mead in Samoa Described a culture in which Gender roles were reversed No sexual jealousy No rape, murder or war Results were appealing to those who were concerned about trends in Western societies Results were later challenged

39. Common Misunderstandings about Evolution Human behavior is genetically determined Environment plays a large role If it is evolutionary, we can’t change it We have the power Current mechanisms are optimally designed Environments change faster than genes. We are stone -age people in a modern world (McDonalds Effect) Every adaptation has a cost and perfecting one system will probably compromise another

40. Limitations of Evolutionary Psychology You can explain the physical properties of an animal with fossils, but behavior can only be inferred. Physical properties often evolve to facilitate behavior, so we can take some guesses Evolutionary psychology relies on genetics and the assumption that all current behaviors served a survival-based purpose in the past, if not currently. So what do you do…?

41. Observe, Hypothesize and Test Phobias Behaviorist approach (Everything is learned) If you fear snakes, you must have been bitten Evolutionary approach Phobias represent an exaggeration of a useful survival tool An inborn fear of snakes provides a survival advantage Most phobias have a legitimate basis (spiders, snakes, heights, strangers, closed spaces, open spaces) Phobias to modern threats (guns, electrical outlets) are rare

42. Choosing a Mate Observe behavior and look for an explanation Men and women both get jealous, but men are much more likely to get violent about it An evolutionary explanation: Men face the problem of paternity uncertainty It is important to defend the “genetic territory” Men are, of course, generally more aggressive

43. Who’s Manlier?

44. Who’s Ovulating?

45. What about this?

46. Evolutionary Psychology may be the Unifying Principle It has tackled Law War Religion Economics Advertising Architecture Cognition, Education, Sociology, etc.