19 mars 2006

Audiobook : The great ideas of psychology

The great ideas of psychology

Daniel N. Robinson

Philosophy Faculty, Oxford University

Distinguished Professor, Emeritus, Georgetown University

Ph.D. in neuropsychology City University of New York

Lecture titles

1.Defining the Subject

2. Ancient Foundations—Greek Philosophers and Physicians

3. Minds Possessed—Witchery and the Search for Explanations

4. The Emergence of Modern Science—Locke's "Newtonian" Theory of Mind

5. Three Enduring "Isms"—Empiricism, Rationalism, Materialism

6. Sensation and Perception

7. The Visual Process

8. Hearing

9. Signal-Detection Theory

10. Perceptual Constancies and Illusions

11. Learning and Memory: Associationism—Aristotle to Ebbinghaus

12. Pavlov and the Conditioned Reflex

13. Watson and American Behaviorism

14. B.F. Skinner and Modern Behaviorism

15. B.F. Skinner and the Engineering of Society

16. Language

17. The Integration of Experience

18. Perception and Attention

19. Cognitive "Maps," "Insight," and Animal Minds

20. Memory Revisited—Mnemonics and Context

21. Piaget's Stage Theory of Cognitive Development

22. The Development of Moral Reasoning

23. Knowledge, Thinking, and Understanding

24. Comprehending the World of Experience—Cognition Summarized

25. Psychobiology—Nineteenth-Century Foundations

26. Language and the Brain

27. Rationality, Problem-Solving, and Brain Function

28. The "Emotional" Brain—The Limbic System

29. Violence and the Brain

30. Psychopathology—The Medical Model

31. Artificial Intelligence and the Neurocognitive Revolution

32. Is Artificial Intelligence "Intelligent"?

33. What Makes an Event "Social"?

34. Socialization—Darwin and the "Natural History" Method

35. Freud's Debt to Darwin

36. Freud, Breuer, and the Theory of Repression

37. Freud's Theory of Psychosexual Development

38. Critiques of Freudian Theory

39. What Is "Personality"?

40. Obedience and Conformity

41. Altruism

42. Prejudice and Self—Deception

43. On Being Sane in Insane Places

44. Intelligence

45. Personality Traits and the Problem of Assessment

46. Genetic Psychology and "The Bell Curve"

47. Psychological and Biological Determinism

48. Civic Development—Psychology, the Person, and the Polis

Lecture 1 – Defining the subject

William James about psychology: “that nasty little subject”. No precise definition: science of the mind, of behavior. Is it a science? The question should be: “Does it yield a scientific explanation?”

In the 1950’s philosopher of science Hempel. Nomological deductive model of explanation: show that it is an instance of a universal law known to be true. It is more than generalization based on what happened in the past. There are no such laws in psychology, biology, economics. Very reliable statistical relations, yes, but laws as stable as the law of gravitation, no. Therefore Hempel calls this an “explanation scheme” opposed to a “full-fledged scientific explanation”. Example of Newton’s gravitation true only within certain limits, then one has to switch to Einstein’s relativity. Yet noone would state that Newton’s law is not scientific. According to his definition, psychology is scientific in areas like the study of sensory psychology, visual information processing, memory, not in the area of personality, psychoanalysis.

Individual experiments are impossible in psychology because no two individuals are similar, and no historical event is repeatable.

Two different possible psychologies. A first brand of scientific psychology is concerned with colour vision, reaction time, memory, alteration of speech ability by brain lesions, calcified glioma and the other with social behaviour. Various behavioural modifications can be obtained by altering the nervous system. This raises the question of a deterministic model for psychology exists, or only an autonomous model taking into account the subject’s free will. Deductive explanation vs. hermeneutics or narrative approach.

Lecture 2 – Ancient foundations – Greek philosophers and physicians

Greek olympic games rewarded winner with a pyramidal cake (the winner takes the cake) that gave their name to pyramids due to their shape. Socrates, Plato, Homer (means hostage). Nativistic, highly elitistic philosophy: men of gold, men of silver, men of iron. No pattern of experience will make a man of iron into gold. Aristotle‘s approach is different from Plato’s: naturalistic, based on observation. By “soul” or psyche, Aristotle refers to the first principle of living things, that is the constellation of life-giving processes. A psychic process can vary in complexity, between animals and humans. In his Metaphysics: “All men by nature desire to know”. Hippocrate’s school of ancient greek medicine is very experimental, avoiding rational deductive approach and instead relying more on observable facts. Naturalistic, scientific. The famous hippocratic oath may have been a pythagorean document, because it calls for two things: keep secret the medical craft, and not help a woman abort a foetus. Abortion existed, and so did medical schools.

Lecture 3 – Minds possessed – Witchery and the search for explanation

Christianity puts a great stress on moral responsibility, moral standing, intentions: free will vs. determinism issue. The first tests to establish witchery were: floatation test, tale of Jesus’ sacrifice and tears, devil’s mark. Doctors and priests were often called to provide evidence in the form of expertise. By the 16th century Johann Weyer expresses some skepticism in his “psychiatric treatise” (dixit Robinson) about the test procedure. In 1628 Burton’s “Anatomy of melancholy” is printed: “Diseases of the mind have their origin in the head”. What they have in common is a movement towards scientific reasoning. We tend to describe those different from ourself by “sick” but we want to be sure we are using the right kind of method, with a settled and undiscussed trial procedure.

Lecture 4 – The emergence of modern science – Locke’s newtonian theory of mind

In the 17th century the authority of sience takes the place of scriptural authority, revelation, customary practises. Newton, Galileo, Bacon, Descartes, foundation of the Royal Society (slogan: “under the authority of noone”). Francis Bacon’s Novum organum (1620): the new “method”. Science progresses by observation, measurement. The way you get the right answer is not by asking the right authority but by using the right method. The ancient philosophers lacked the right method.

R.Descartes (1596-1650): father of analytical geometry, specialist of optics, philosopher, logician. Supply a rational being with irresistible evidence of truth. Newton (definition: natural philosophy = science). Experiment to test hypotheses. Galileo used a telescope in 1609 to find the moons of Jupiter, in contradiction with the fixed number of celestial set by the official theory.

Newton: a system is reducible to corpuscles held together by physical forces. John Locke was an admirer of Newton and applied the same principle to psychology. Simple sensations put together form complex ideas. Are there things of a platonic nature that we know innately beyond the reach of experience? Locke opposed the view of innate ideas supposedly advanced by René Descartes.

Descartes: Suppose we only know through experience, then how could we recognize that there is a material world if we only knew sensations provided by this world? We couldn’t. Nature nurture issue. John Locke: empiricistic tradition of psychology. Descartes: rationalist, nativistic view.

Lecture 5 – Three enduring isms – Empiricism, Rationalism, Materialism

Locke’s empiricism is not absolute. He refers to a number of “original acts of the mind”: up/down distinction, law of contradiction. David Hume is more radical in his Treatise of human nature (1739). He states that the concept of cause is just a habit of the mind to regard cunjunct events as causally related: “Anything may be the cause of anything”. We have a tendancy to associate. This is a very psychological view of philosophy.

David Hartley was influence simultaneously by Hume and Newton. The laws of association are to be understood at the level of physiology. John Stuart Mill was even more psychologically oriented, radical empiricism. Even matter is defined as “the permanent possibility of sensation”. For anything to be is to be perceivable. His influence is felt until Skinner (behaviorist).

What the rationalists claim is that knowledge is a rational reconstruction of reality based on the isolated facts of experience. They claim that the greatest achievements of human life have an undeniably rational character: abstract mathematics, astronomy, physics.

Leibnitz (rationalist) criticized Locke: to the statement “nothing is in the intellect, it all begins in the senses” he replies “except the intellect itself”. Kant (rationalist) argues that causality relies on time and space, and since those are not given by experience they must be present prior to experience. This tradition of rationalism culminates with Jean Piaget (formation of the child’s concepts of necessity, universals).

Metaphysics refers to two issues: what has real existence (ontology), and how we can ever know anything (epistemology). What materialism asserts is that anything ontologically real is material, reducible to some aspect of matter/energy. There cannot be totally non-physical, immaterial, existing entities. Therefore our mental life, rational powers, experiences, ideas, etc. are ultimately to be understood in terms of organization of the body and brain. Thomas Hobbes wrote in his Leviathan that the essential nature of humanity is as a mechanical entity. Julien Onfray de la Mettrie wrote by the middle of the 18th century “Man, a machine”. To this day, we consider that body and mind are not separate entities.

Lecture 6 – Sensation and perception

In the beginning of the 19th century in Leipzig, Weber got interested in the acuteness of human observations. How different must two weights be for an observer to feel it? He discovered Weber’s law: the difference (delta) between a comparison and a standard has a constant ratio to the standard for the difference in stimuli to be perceivable. For the first time, perception followed a fix law! This work influenced Gustav Fechner, writer of Psychophysics. Fechner wants a law of sensation magnitude, not only a law of discrimination as stated by Weber.

Fechner’s law states that the succession of noticeable differences in stimuli follow a logarithmic growth R = K.log(S) where S is the stimulus, and R the sensation. Weber’s and Fechner’s laws tend to break down at the extremes. Pitch and brightness follow a logarithmic law, whereas loudness does not and follows an exponential law. Hence Stevens stated a more general law R = S^K.

Lecture 7 – The visual process

Two classes of receptors: rods and cones. Within the fovea there are only cones. In the periphery of the retina there are more rods than cones. There are 130 millions receptors: 126 rods and 4 cones, but only 1 million optic nerve fibers per eye. The information is concentrated by bipolar and ganglion cells. In the fovea, each cone has its nerve, but in the periphery there is one nerve for thousands of rods. Therefore the peripheral retina has a lower intensity threshold. Acuity in the center, lower threshold in the periphery.

Lecture 8 - Hearing

There is a muscle that has a dampening effect on the eardrum when the intensity of the sound is too high. This is a unconscious process. Hair cells in the inner ear act like piezoelectric devices giving an electrical response proportional to the sound stimulation. The auditory nerves carry impulses with frequency-coded intensity and different fibers for different pitches. In some frequencies, increasing the intensity results in a perceived increased pitch (auditory illusion). Because a single axon cannot fire more than 1,000 times per second, several fibers are used to code high frequencies. The information gets concentrated as we move along the auditory nerve towards the cortex, in which we achieve a very fine bandwidth detection. Audiogram = graph of the intensity of sound required to be heard in a range of frequencies.

Lecture 9 – Signal detection theory

In real-life situations, perceptual functions must distinguish sensory informations from all kinds of background noises. The signal detection model aims at explaining the process doing this. Example of security radar systems that must not confuse geese flocks with ICBM missiles! This requires a set of criteria: signal strength, speed, trajectory. Recognizing someone is a perceptual tasks involving: appearance (sometimes partially hidden), voice tone, place and time, movements. The criteria are set empirically to improve the probability of a correct detection, but will never achieve 100%. Some geese will be mistaken for ICBMs and vice versa.

Technical term: ROC curve = Receiver Operating Characteristics of a detection system. It is the probability of correct detection plotted against the probability of false detection. Experiments to determine the absolute indifference thresholds in vision and audition. If you tell the subject “don’t guess, tell us only when you do see the very dim flash of light” the threshold is overestimated. On the contrary you can provide a payoff matrix that moves judgements towards low thresholds by saying “if you miss a flash you must pay $1, if you see a flash you get $2”. Studies of this sort show that a subject can make better than chance guesses down to signal levels as low as one photon for light.

A jury at court can be seen as a crime detection system. It must be provided as much information as possible, rules and evidence and sufficient number of jurors to reduce the risk of error. This is why fingerprints are seen only as circumstancial evidence that the defendant killed the victim. Together with motive and traces of powder, it makes conviction possible.

Lecture 10 – Perceptual constancies and illusions

Difference between sensation and perception: the latter involves complex processes. Efficient perception improves the survival of a species by helping solve certain problems that cannot be solved at the sensory problem. Example of silhouette of head and shoulders of Bob coming over the hill: he is “perceived” to be 5 to 6-foot high independantly of the size of the retinal image. This is a typical example of size and shape constancy phenomenon. Distal cues: identification of an object through the set of informations we have about it (where it is, when, size, motion, etc.). Proximal cues: judgement of its properties determined solely by sensory experiences (retinal cues).

Constancy phenomena are not an error of our perception, but a mechanism to overcome distortions that can occur at the sensory level and could induce identification errors. A sheet of paper under dim light is seen to be white, not grey. But sometimes, the context can produce illusory perceptions: moon illusion (moon appears larger when close to the horizon) still not explained to this day in spite of numerous experiments and theories.

Constancy of self. Example of Locke’s theory explaining the sensation of identity by the collection of memories. This does not work because totally amnesic patients nevertheless experience continuous identity. Little babies know that it is their thumb going into their mouth. We know that we are the same person waking up in the morning who went to sleep the previous night.

Anthropological studies of people raised in natural, architecturally spare environments, show that they do not display some of our visual illusions (Poggendorf illusion). These illusions can therefore be the result of a lifetime spent in a given perceptual environment.

Lecture 11 – Learning and memory – Associationism – Aristotle to Ebbinghaus

Aristotle was very interested in people with great memory (mnemonists). He understood that repeated experience and rehearsal enhances memory and even character (habit of virtue). As usual, he justifies this by a biological process: impression of a signet in wax is best repeated over and over. Such a trace therefore gets erased (forgotten) with the passage of time (trace decay theory). In the medieval period, intelligence was measured mainly in terms of memory because this was the first source of information.

In the 19th century, Ebbinghaus started experimental psychology in the field of associative memory. He used nonsense syllables (trigrams such as sop, til, lar, nif, etc.) associated with words and presented them repeatedly to his subjects. He then asked what word is associated with each trigram and measured the success rate after an increasing number of presentations, and after various amounts of time. This confirmed the trace decay theory of the ancient world. He also showed that retention is optimal for the first and last portions of the list (principles of primacy and recency).

How much can we hold in memory? Depends whether we have been exposed once to the information, or have had long practise (span of apprehension). It depends on the meaningfullness and vividness of the context, but for one exposure it is around 6 to 8 items. But span of apprehension theories initially made no distinction between memory and retrieval. In fact we can store more items, but cannot always retrieve them. A tachistoscope is used to present a stimuli very briefly: 7 x 4 grid filled with capital letters. We can then retrieve 7 letters. But when presented with a little arrow pointing to an empty location in the grid, we can recall around 15 items (cued retrieval technique)! This can be compared with the technique used by psychoanalysts to uncover never really forgotten unconscious memories.

Lecture 12 – Pavlov and the conditioned reflex

Lecture 13 – Watson and american behaviorism

Lecture 14 – B.F.Skinner and modern behaviorism

Lecture 15 – B.F.Skinner and the engineering of society

Lecture 16 – Language

Lecture 17 – The integration of experience

Lecture 18 – Perception and attention

Lecture 19 – Cognitive maps, insight, and animal minds

Lecture 20 – Memory revisited – Mnemonics and context

Lecture 21 – Piaget’s stage theory of cognitive development

Lecture 22 – The development of moral reasoning

Common sense definition of moral value says that what is moral is what is useful, serving best interest of ourself and others. Jeremy Bentham (end of XVIIIth C) : “nature has placed us under the governance of two gods : pleasure and pain”. This is a hedonistic moral theory.

Utilitarianism say not only that maximizing utility determines our acts, but also determines what acts are good. Story of mob wanting to burn a prison with innocent prisoner inside: if the prisoner is released several people may die in the fire, but we will not kill an innocent person. If the stakes are so high utilitarianists argue that conceding to the terrorists is the right thing to do.

Deontology is the opposite view. The rightness or wrongness of an act is not determined by its consequences but by the principles it instanciates. Main supporter: I.Kant. Categorical imperative: “So act that the principle on which you are acting is a universal law”. If I simply maximize utility, seeking pleasure and avoiding pain, I am acting according to the “natural law”, not as an autonomous being choosing an intelligible course of action.

Sympathy theory says that good or wrong acts spontaneously make us feel pleased or revolted (A.Smith, D.Hume).

Lawrence Cohlberg contributed to moral psychology. Tells a story and asks subjects if an action was right or wrong, like Piaget had done earlier. With little children, answer depends mainly on parental behavior (punishment = bad action). Piaget thus defined heteronomous and autonomous moral judgements (based either on other’s or on one’s own judgement). Cohlberg refined: yong children anticipate parental punishment, later seek a rule given by authority (parents, teachers: adults), later rely mainly on peer group to which one belongs, later make autonomous reasoning.

Is there a difference between men and women on moral judgements? Maybe women tend to be more intuitive, empathetic, less prone to logic and reasoning. Are these differences due to gender differences or early experience? This work is still in progress…

Lecture 23 – Knowledge, thinking and understanding

Greeks: scientific knowledge, causes of things, rules (episteme) – practical knowledge for a political leader, a company manager (fronesis?) – wisdom (sophia).

Do we know certains things in an innate way as rational beings? Example in Plato of dialog between Socrates and youngster who knows that the area of a square is uniquely determined by its diagonal. This is a nativist, rationalist view.

Aristotle was much more practical, had studied 20 years in Plato’s academy, then taught Alexander the Great, then left to found his own school. Empirical knowledge vs. theoretical knowledge which can be generalized. Heuristic = “rule of thumb” to solve certain problems. Computers still have trouble doing this. Example of short, skinny person wearing glasses and a tweed jacket: librarian or farmer? Heuristics are extremely useful although they can often be misleading.

Algorithms are quite different: they are a systematic method to solve a problem. Problems of arithmetic can unfailingly be solved by algorithms. Alan Turing worked on the question whether a given problem could or not be solved by an algorithm (computable). Functional fixedness = tendancy to hold on to an algorithm with problems for which it does not work, “use the rake to stir soup”. Often found in “neurotic” type personalities. Availability heuristic = most recently used heuristic, can therefore be misused.

We need to be able to abandon certain heuristics when they are not efficient. Example of matchstick problems where matchsticks must be laid in three dimensions to solve the problem. Newton had the ability to abandon heuristics that were until then serviceable and invent a new one to explain gravitation. Apart from this, when asked at the age of 86 what the greatest achievement of his life was, he answered it was lifetime celibacy!

Lecture 24 – Comprehending the world of experience – Cognition summarized

Perception vs. cognition. Cognitive processes are usually propositional sentences, framed as statements about what we experience. Piaget’s concept of conservation: fat and thin beaker filled with inky water. The scientifically, empirically exact answer is that the second beaker contains less liquid. But most subjects will use the law of conservation. Example of Helmholtz stating that it is impossible to make perpetual motion machines. Conservation of energy. Laws of physics do not reflect a perfectly accurate perception of reality, but a idealized conception of the world. Exemple of law that can be stated if the inaccuracies of the real world are canceled: if a is greater than b and b greater than c then a is greater than c.

Saint Augustin was dealing with heretics denying certain attributes of God on the ground that there were no sensory evidence of such claims. Saint Augustin uses an example (later used by René Descartes): everyone can perceive a four-sided figure (rectangle), cannot perceive a thousand-sided figure, but can nevertheless conceive a thousand-sided figure. Other example that the punishment should match the crime: this is true conceptually, not perceptively (a rape for a rape). Conservation of energy is a model in conceptual, cognitive life. A substitute for real, perceptive life.

Karl Lashley (1930’ and 1940’). Lashley jumping stand with two cards with circles of different sizes. A rat easily learns to jump at the largest circle, this still works with various sizes of circles. This is transpositional learning (we recognize a melody played in any tone). Cognition is to perception what finding is to seing. This also leads to the confirmation bias: once we accept a hypothesis, we look for means of confirming it. “My mind is made up, don’t confuse me with facts”.

Lecture 25 – Psychobiology – Nineteenth century foundations

Now we will turn to psychology in the materialistic tradition. The mind-body problem: How can a brain initiate an idea? How can a thought make the body move? Descartes was a dualist, he believed that reality required two kinds constituents: mental and physical entities. He was also an interactionist: the mental part of our life operates on our physical behavior, but he does not regard the body to have the power to make the mind think.

Circa 1800, clinical findings in neurology began to change this purely philosophical view. Franz Joseph Gall is known as the father of phrenology (“bumpology”) which is unfair to him. He did this by examining the nervous system of feotuses, and various dead people and animals. He considered that our intellectual dispositions were innate, that for every aspect of the personnality there is a region of the brain associated with it, that the development of a faculty depends of the share of the cortex devoted to it, therefore pushing out bumps on the skull. The last English-language journal of phrenology was published early in the 20th century.

Tests were made by ablating particular regions of the brain in animals. Modular theory of mind. This proved Gall wrong in locating specific functions in the brain

Karl Lashley used maze learning and exposed the animals to surgical procedures, searching for the n-gram, a place where a given information is stored. He could not find it. Regions associated with functions were identified, but none for memory and learning. After surgery, the animals can recover and reacquire the maze. The degree of deficit depends more on the quantity of brain removed than on the region removed. We now know that the hippocampus is vital in memory and its lesions can produce selective deficits, and that the prefrontal cortex is involved in short-term memory.

Lesson 26 – Language and the brain

Descartes had almost raised the question of the Turing test: can one make a machine duplicating the characteristics of a human being? He had been inspired by hydraulic processes in french gardens. Three things that would distinguish such a device: idea of God, abstract conceptions, creativity in language. This goes back to Stoic philosophy: as language users we form a very special class of animals. Yet our brain is quite similar to an ape’s.

Broca in the 19th century studied a patient who could not utter a coherent sentence and otherwise acting normally. The post mortem examination of the brain showed a lesion of the brain on the left third frontal convolution (Broca’s area). The cortex is split between motor, sensory and association areas. Broca’s area falls in the latter. Other symbolic functions can be altered by cortex lesions: agraphia, acalculia, amelodia. Wernicke’s area when damaged impairs the sense of language.

In intractable epilepsies, the mirror focus of the discharge can be avoided only by sectionning the corpus callosum connecting both hemispheres (commissurotomy). Animals undergoing such surgery look healthy. It was performed on patients with life-threatening patients: they perform fine in neurological examination. Some other impairments: visual agnosia (the patient cannot interpret what he sees but ok with the help of tactile cue), apraxia (cannot coordinate movements to perform usual tasks). Commissurotomized patients, when seing an object with only one eye and the perceptual information does not go to the left hemisphere, will not be able to name the object.

There clearly is bilateral representation of language functions. Recent evidence suggest that, on average, women have a more elaborate linguistic side than men. Chomsky believed that the universal generative grammar is expressive of underlying innate brain mechanism.

Lesson 27 – Rationality, problem-solving, and brain function

Despite the fact that functions are closely associated with specific regions, we must recognize the plasticity of the brain, even more so in young people. John Waber, pediatric neurologist, studied hydrocephaly in children who had had surgery to shunt the cerebrospinal fluid and survived the disease. Petscan showed that, although these patients had developed normally, in some instances massive regions of the cortex had not developed at all (up to 30% or more of the cortex replaced with fluid space). One patient had no occipital cortex at all and yet could see normally. As a result of the early injury of the visual cortex, others areas of the cortex took on functions normally served by the occipital cortex. The remaining question is: what mechanisms give the initially plastic brain tissues the specificities they later have?

Is there a particular region of the brain for rationality and problem solving? Frontal lobe lesions have been identified to specific cognitive deficits:time binding (the patient cannot solve a problem if the solution involves referring to a past solution), perseverance (the patient might repeat sentences over and over), deficit of availability heuristic, diminished flexibility in problem solving.

Alzheimer‘s disease is difficult to diagnose. Formation of ameloids correlated with the condition, why? On the average they show a 40% shrinkage in the hippocampus, which can explain deep alterations in memory functions and personality. Nootropic drugs (from greek noos, reason) can improve the patient’s cognitive functions.

Autism. A given autistic patient has made a list of all major cities in the U.S. and needs to visit them all in alphabetical order. If the order is violated, the trip must be started again from A. His voice is very flat. Yet this patient can solve problems. He does not give rational explanation of his actions, just “you must do this”.

Lesson 28 – The emotional brain – The limbic system

Fear and pain are an evolutionary necessity to keep us away from dangers. Therefore these basic emotions should exist also in animals. Evolutionary theory does not state that humans are more developed than other species. Measure the IQ of rhesus apes would be like using a thermometer to weigh oranges.

Paleocortex and subcortex form the limbic system and appear in reptiles who yet have almost no developed cortex. They are associated with emotional functions: sexuality, care of the young, aggressive behavior, fear. Subcortical areas project fiber pathways to the cerebral cortex, which does not “control” these “old” functions. Diplodocus rex developed a subsidiary brain halfway down its back to control the tail.

Rhesus monkeys with bilateral temporal lobe ablation become very placid, but have increased sexuality. This is due to the removal of the limbic system associated with the lobes. Many things considered instinctual are actually highly responsive to environment: research of Kuo on predatory behavior of cats showed that it depends much on what kitten have seen their mother doing (catching and/or killing and/or eating rodents).

Are there pleasure and pain (reward and punishment) centers in the brain? James Owls and Peter Milner discovered that some regions of the brain act as positive reinforcers if the rat can stimulate them when a lever is pressed. There seems to be larger areas associated with pleasure than pain. The hypothalamus has regions that will cause hunger, or on the contrary aphagia. Bentham’s assertion can be considered true at the subcortical level.

Regions of the limbic system can initiate sexual activity. Electric stimulation of the limbic system has been experimented on a human volunteer and it caused sexual arousal.

Lesson 29 – Violence and the brain

Long history of insanity defense before court, starting with the “wild beast” idea that a person so bereft of reason could not be held responsible of his acts. In the recent “Twinky defense”, youngster argued that their diet of chocolate bars had altered their ability to respect law. Sleepwalkers assaulting their wife in the middle of the night believing they are fighting against a soldier. John Hinckley has not succeeded at school, became fond of actress Jodie Foster, and threatened to shoot the President to attract her attention. The judge released him after a minor offense, after which he shot Ronald Reagan but was found not guilty by reason of insanity by the jury because the State had not managed to prove sanity. The law has now been changed but it then was the State’s burden to prove it!

What could a juridiction do if it were proved that all our actions are causally determined by an event in our brain? The law has resisted this notion because it could not survive a totally deterministic neuropsychology. If something in the environment makes us inclined to act in an unlawful way, we must resist it. By adopting a more and more scientific perspective, courts find themselves at cross-purposes with the very concept of law. Deborah Denno wrote in an article that we should consider for law a midpoint, between radical determinism and the totally voluntaristic perspective.

Lesson 30 – Psychopathology – The medical model

Is the medical model not the right model after all? Main transmitters: acetylcholin involved in memory, norepinephrin in vigilance, serotonin in aggression, mood (depression) and appetite, dopamin in Parkinson’s disease, pleasure and reinforcement, GABA in epilepsy, glutamate in all neurons, endorphins in pain attenuation.

Robinson thinks that main psychiatric diseases correspond to patients suffering from neurochemical alterations of will respond to such agents. By the end of the 19th century it was accepted that psychiatric diseases are a neurological condition. Temporal lobe focal epilepsy: (temporal lobe is the thumb of the boxing glove) a calcified glioma a tenth of the size of a nail can form in the lobe and create epileptic discharges on EEG, without any signs of seizure. Instead the patient undertakes a complex series of actions including aggressive behavior and then forgets everything about it. If the calcified glioma is surgically removed, the disease can be cured.

Manic depressive (bipolar) states can become manageable with Lithium. In such cases, a totally desperate person can become happy in a matter of weeks. If it is the case here, why not everywhere? Thomas Szasz is a psychiatrist considering that there is no such thing as a mental disease because diseases concern organs and the mind is not an organ: “The myth of mental illness”, “you cannot treat a disease by talking to it!”. For him, the disease can only exist in tissues, but can have psychological manifestations.

Paul Neil asked: “Suppose there was only one fact you could know about a person to identify someone as a schizophrenic, it would be finding someone with a schizophrenic identical twin”. Heritability of schizophrenia is 0.6 to 0.7.

Lesson 31 – Artifical intelligence and the neurocognitive revolution

Can a machine achieve the mental life experienced by human beings? During the war, there was a lot of research by Alan Turing on code-breaking of Enigma. Turing developed a general theory of solvable (computable) problems. He sketched in the journal Mind what a computer hidden behing a curtain and answering questions would have to do to qualify as intelligent: be indistinguishable from a human counterpart. This came to be known as the Turing test.

Is the program “playing chess” as masters do? No. Does chess playing captures the usual performance of human mind in life? No. Machine functionalism: AI thesis stating that to be intelligent, a machine needs only to answer in a seemingly intelligent way to questions which require intelligence, no matter what its inner workings are. Expert systems have been designed to mimick expert judgements of human specialists in various fields. What would happen if they start giving the same answers as human experts?

The only thing such machines would be lacking is our biology. But there are some human beings who are totally deprived of rationality and intelligence by a disease and nonetheless are considered human. AI specialists therefore claim that the most remarkable machines should be considered intelligent. Where is language all about? How do we arrive at the notion of truth. Where do meanings come from? Are these notions purely cultural in nature so that these notions become inintelligible absent a contexte of culture?

Lesson 32 – Is artificial intelligence intelligent?

AI forces us to identify what makes our mental life so special, to examine what we are doing when thinking and problem-solving, and constitutes a test of the materialistic psychology. Gödel’s theorem has been used by opponents of AI: an intelligent system would be doomed by the incompleteness theorem. Since Gödel was able to prove his theorem, there must be something about human intelligence than can’t be captured by a formal system.

John Searl raised the question: “What does a computer actually do?”. He proposed the Chinese room image: a stack of cards with Chinese ideograms is in a room with instructions to lay cards out from left to right in a given order that will make sense to a native Chinese speaker but not to you. This, says Searl, is what is going on in a computer. Searl argues that all intelligent activity requires meaning (intentionality) which cannot be represented in a computer.

Following a rule or having a purpose? When solving a problem, a human being is not just functioning, getting something done, he is “trying” to get it done. Wittgenstein stated that we become intelligible to one another because of a cultural environment. Example of the beetle and the box. Meaning cannot exist within one’s own private sphere. Therefore a device cannot have meaning unless it is deriving it from a community of beings, and such a community does not exist for “intelligent devices”. Therefore a computer can at best spit out words that make sense to us as a given form of life, but not to itself.

Lesson 33 – What makes an event social?

We have so far left out interpersonal and cultural relations, except for Wittgenstein’s thesis on meaning. Aristotle on how should we explain someone being angry: changes in the temperature of blood itself being cooled by the brain! (physicos), or emotion arising from interaction with someone else (dialecticos).

To make a decision, a court needs a larger narrative context to make the criminal act intelligible. This cannot be reduced to physiological measurements and causal explanations. Therefore a social, historical or economic event is an event which can only be explained by aspirations, motives, purposes not translatable into the physical world.

Aristotle defines efficient causation as the effect of a chisel on a sculpture (billiard ball hitting another billiard ball), on which modern science focuses. But the first causal event is the idea the sculptor had of the object he wanted to make before he actually started. Explanations based on considerations of goals and purposes are called teleological. Bees achieve purposes serving the interest of the hive without each bee having an intention to do so. Darwinism therefore achieves a teological explanation without the organisms being aware of it. In the freudian theory, goals are realized unconsciously.

F=m.a can be experimentally tested but we do not require this scientific law to make sense, to match up with our feelings. Whereas social phenomena we regard as insufficiently explained unless the explanation is intelligible. This is related to our capacity of empathy with other human beings, this is exploited by successful novelists. In bad litterature the characters we say that are not credible when there are no grounds of empathy. Narrato-logical explanation: works as a story, without requiring it to be true but related to a given context and culture. Also hermeneutical explaination (requiring interpretation).

Lesson 34 – Socialization – Darwin and the natural history method

The darwinian framework studies not only the processes but also the context. It will be used by Freud as well as Skinner. The 18th century hosts the idea of progress. In the middle age, the world was regarded as harmonic, symmetrical, cyclical, much like in the classical conception. After Renaissance, large cities have appeared and one can achieve a personal carrier more easily. In the same way, the world is understood in organic terms, progress through competition. Condorcet wrote on the stages of human development. Freedom becomes the basis on which we can metamorphose into something else.

The evolutionary theory therefore has a deep philosophical tradition which continues in the work of our contemporaries. Darwin studied in Cambridge, started as a naturalist and made his trip to the Galapagos. His theory exposed in the Origin of species was badly received by the clergy, but the reviews were rather good. Some asked why man was never able to produce a new species by selective breeding. These were mainly scientific arguments.

Darwin then publishes more speculative books, the Dissentive man and The expression of emotions in animals and man. They address the essence of human nature, and focus on sexual selection with little data to support them. Lamarck thought that a shoemaker with the hammer in his right arm would have offspring with strong right arms (…). With Darwin now the organism is now understood to pass on characteristics to its children, meanwhile progressively refining the collective features and increasing the potential of the group.

Lesson 35 – Freud’s debt to Darwin

Darwin’s natural history method is teological, and it is also a narrative description, a kind of epic account. This translates into psychology seeking for narratives explaining the patient’s behavior, and not only clinical observations. In sexual selection, mating is guided by an unconscious purpose: the survival of the species. There is a parallel to be made with Freud’s theory of unconscious.

Nomothetic vs. ideographic explanations in psychology. A nomothetic explanation is framed in terms of a general scientific law (cf. Hempel, nomological deductive model) and therefore arguably does not apply to psychology. An ideographic approach takes each individual case as unique. Freud and Darwin rejoign in considering that both nomothetic and ideographic explanations are required to understand human behavior.

Some important aspects of human psychology are not acquired. Chomsky’s theory: although language vary throughout the world, the age at which children achieve grammatical structure is the same everywhere. Darwin’s theory is very much instinctual. What is it we must know innately and don’t have time learning for us to survive? Freud comes up with a list: feed. Infants will do this by sucking instinctively because they do not have time to learn it. Why does the baby do it? Because it yields great sensual (= sexual) pleasure. The baby’s purpose is self-gratification.

Lesson 36 – Freud, Breuer and the theory of repression

Freud was trained in neurophysiology in Vienna and showed exceptional skill. When studying hysterical symptoms, Freud was inspired by the principle of conservation of energy, stating that psychic energy blocked somewhere will manifest itself elsewhere. As a Jew in Vienna, Freud had to leave the world of academic studies to move to medical practise. He works on neurological symptoms that cannot have organic origins (glove anesthesia: unsensitivity in a region of the body). His initial modest objective was to identify the cause of such symptoms.

He then goes to Paris to listen to Charcot on curing hysteria through hypnosis. Hypnosis was developed by Franz Anton Mesmer (Vienna) who had financed Mozart’s first opera and moved to curing paralysis with magnets and hypnosis. Charcot found that hysterical patients could be cured this way, whereas organic patients couldn’t. Freud hears Charcot’s lectures and makes several critics: not a universal cure, temporary effects, somewhat mystical process. Following Helmholtz and Mach, Freud wants to rid science of such ancestral traditions. He wants his theoretical psychoanalytic language to match experience.

Breuer is a slightly older colleague who has a hysterical patient who believes that she is receptive to a “talking cure”. Freud and Breuer then notice relief in patients who are led to talk about their condition and problems. Their explanation is that hysterical symptoms are formed by a repressive mechanism on the flow psychic energy, and the latter can be released by discourse and free association. This is a mechanistic explanation. The unconscious will later be identified as the place where this repressed material is located. Dreams, slips of the tongue, will come later.

Lesson 37 – Freud’s theory of psychosexual development

It is an evolutionary theory: evolution of sexual maturity in the organism from infant to adult, and sexuality serving the preservation of the species. Freud had a scientific training and wanted to avoid any metaphysical speculation. He asks himself what we find in early infancy that would serve the preservation of the species. The guiding principle is pleasure, which exists in animals avoiding pain. But Freud seeks rules by which we manage the trade-off between this principle and the rules of life in society. It is a biosocial theory.

During the oral stage, Freud saw sucking as providing sexual gratification. Then during the anal stage, gratification is achieved through the eliminative functions of the body. For the first time, the child can now influence his parents putting a lot of effort into toilet training. In the genital and phallic stages, the entire process of psychosexual development reaches its goal: successful reproduction. Therefore, homosexuality is seen as an incomplete development because the sexuality is non reproductive.

The reality principle states that certain forms of gratification have a cost, therefore creating a life long conflict. The principal source of gratification for the infant is the mother or nurse. She therefore becomes the first target to receive sexual interest, yet this is socially not acceptable. Freud goes back the ancient greek world find his inspiration: the Oediple complex is a weak theory, maybe not a theory at all, more a narrative account which cannot be scientize it. The castration anxiety arises from the recognition that the mother is already spoken for, and one must resist this. Psychanalysis sometimes explains homosexuality as being the result of an Oediple complex resolved by adopting a female posture.

Freud says these impulses are played unconsciously and can be uncovered through the interpretion of dreams. We have techniques to protect ourselves from socially unacceptable unconscious impulses. These primitive biological impulses necessary for the survival of the species form the “it”. The pleasure seeking creature must develop a conscience to resist these impulses, a superego. The ego is the person as one knows oneself, the extent to which one has self control and is socially accepted or not. The neurotic symptoms appear when these ego defense mechanism are most fully engaged and stop working. Freud considered the cure to be a reeducation, first reliving the events and then acquiring a new set of dispositions.

Lesson 38 – Critiques of freudian theory

“Is freudian theory right or wrong?” is not a question often asked by contemporary scientists. Psychoanalytic as it was developed could not possibly be confirmed scientifically. In his correspondance with Jung, Freud appears small-minded, requiring orthodoxy. Jung appears on the contrary as a gentleman, open-minded. Freud was conscious that he was launching a movement, which in fact survives today.

The Arapesh do not show any sign of Oediple complex, in addition to their pacifism. The neo freudians considered the development of personality to depend more on social environment and culture. Erikson’s multi stage theory of personality development (the ages of man) gives an example of a different view of human nature. The infant stage is characterized by attachment to the mother. The next stage (3 to 6 yo) is that of independence. From 6 to 12 competences are developed: they yield confidence that we can achieve our goals (positive feedback for our good actions). Adolescence is the training ground for social and civic life. Then adulthood, middle age, etc.

Correspondance of Jefferson and Smith until they die on the same day on a 4th of July.

Lesson 39 – What is personality?

What is meant by personality? How many might there be? Locke’s theory was that personal identity of an individual is the accumulation of one’s experiences. There are genetic alternatives, that consider that there are types of personalities. These started with Theophrastus who wrote about a set of orientations and dispositions that will appear in a variety of contexts, not to be altered by experience. Greek tragedy also refers to curses on the progeny of a family.

In the 18th century, various personality types were developed in order to predict moral and intellectual faculties, for instance in criminal studies, phrenology, physiognomy (morphopsychology). Captain Fitzroy told Darwin that he almost did not get the position of naturalist on the Beagle because the shape of his nose was not what was to be expected of a great naturalist!

The big five emerge as the most often cited personality types: neuroticism (tenseness, worry, anxiety), extraversion (attract attention otherwise frustrated), openness (tolerant, not easily shocked), agreableness (nice, positive, conceding, avoiding confrontation), consciousness (reliable, devoted to duty). Each of these types has its opposited, and even a continuous scale between both extremes. Do these reflect genetic predispositions? They can be gender-specific.

Lesson 40 – Obedience and conformity

Several researches have shown that social context can take over acquired behavior traits. Solomon Ashe asked subjects to find a line matching the length of a standard line. Although 90% get a right answer, this will go down to 30% if the peers in a large group are proposing a wrong answer. Stanley Migram hired volunteers in a supposed study on the effect of reward and punishment on memory. One third left before the end but he got two thirds of the others to “electrocute” other citizens up to the level of “Danger, high voltage”. This can be explained by the authority of the organizers, and the “obedient personality” of the participants.

Philips and Bardo did studies involving undergraduates at Stanford playing a role game where some are to be prisoners emprisoned in cells, and some guards with a uniform who should preserve order. They had to call off the experience because of the pathological dependance that quickly formed in the prisoner population and the sadistic behavior that appeared in the guard population. All were informed that they could quit the experiment at any moment, but they are tied by the situation and this overcomes their entire history of moral reinforcement.

These researches point out the necessary balance between obedience to authority and resistance when the orders become outrageous. Is it ethical to engage volunteers in such research without properly informing them?

Lesson 41 - Altruism

Critic of Darwin by Alfred Wallace: he considers that evolution does not explain esthetism, interest for abstract matters like philosophy and mathematics, tendancy towards altruism. But dogs can have an altruistic behavior not only towards other dogs but more strikingly towards humans, saving children from drowning, fire, rescuing people in avalanches. Dolphins also come to the rescue of those drowning at sea.

Most social scientist prefer to speak of social exchanges rather than altruism. We feel endebted when others do something for us which we did not ask for, it is the reciprocity principle. On the contrary, bystanders are people who will turn away when someone calls for help. There is a fairly general pattern: one will engage in altruistic behavior depending on what other people are doing (the larger the number of people not helping, the less one helps). The behavior of peers has a very strong influence on one’s own behavior.

When Aristotle tells us that we are social animals, and have a strong inclination to live in the company of others, he says the same of bees and the like. Be our specificity is to pause, and see what others are doing, thinking, feeling, needing.

Lesson 42 – Prejudice and self deception

Racial prejudice and discrimination in the United States. Prejudice means pre-judging, making a judgement on someone before the evidence comes in. This belongs to the same area of psychology as stimuli generalization, type identification and inference heuristics. But statements such as “they are all alike” are at the expense of the individual itself, absorbing it in the collective. Such generalizations are called outgroup homogeneity.

If asked whether a reserved, neatly groomed, thin person sitting upright with hands in lap is a farmer or a librarian, most people will answer the latter. This precise categorization would statistically be wrong because there are far more farmers than librarians. But our mind uses such a heuristics because they are usually quite efficient. A simple way to get types is the use of uniforms, since they even change the way we regard oneself.

It is not true that society would be better of ridding itself of such group identification tendancies. A sense of community can only be grounded exactly on such behavior, identifying common features in the members of the community. The fundamental attribution error refers to the emphasis we put on personality traits in explaining people’s behavior versus contextual factors. The ultimate attribution error is where we locate within an entire group certain dispositions that account for its shortcomings. Difference is accentuated, and what is never invoqued is the common humanity and grounds for similarity.

Why was the holocaust perpetrated against the Jews and others?

Lesson 43 – On being sane in insane places

David Rosenham’s article: “Being sane in insane places”. Who controls the definitions of labels such as “disturbed”, “neurotic”, “witch”? At least two definitions: self-reference (my group is normal), law (outlaws, homosexuality). Thirty years back, homosexuality was listed as a crime by law in most federal states, and as a mental illness in the diagnosis and statistics manual. Other definitions: that given by expertise or the medical model. John Hinckley pointed out in his insanity defense that his cortex scan showed a certain swell.

Psychopathology is not to be confused with problems of social adjustment. The latter sometimes says more about the society than on the subject himself. There was an experiment in which some of Rosenham’s students and colleagues got admitted in a psychiatric hospital pretending to have a given problem, but then behaved totally normally once inside the institution. The fake patients were “typed” during admission, and the experiment shows that these types did not change later on although their behaviour was normal.

Note that homosexuality was removed in the list of diseases in the DSM after a majority vote within the american psychology association. The justification was that, since no attempt to “cure” homosexuality had worked (psychology, pharmaceuticals, law), it could not be considered a disease (!).

Lesson 44 - Intelligence

In ancient times, people with a great memory (walking textbooks) were revered just as we revere today people with a high IQ. At the end of the 19th century there was an exodus from farms to cities in France, and a growing concern appeared as to which children had the ability to achieve normal results at school. Alfred Binet then was a first rate experimental psychologist, and he was asked to measure the children’s ability. He created tests to check if a child of a given age know what the average children of the same age know (statistical definition). They were fully aware that these tests were very sensitive to cultural background and tried to remove most of cultural loading.

In the US, some states made these objective tests mandatory very early on in order to fight racial prejudices. Intelligence tests in the US were initially promoted by people with a racist agenda. In the 70’, it was found that large numbers of black and hispanic children were rated “educable but mentally retarded” according to these tests. Following this, the tests were forbidden in fear of their discriminatory consequences: “breaking the thermometer to fight the fever”.

There is a theory that intelligence follows a normal distribution (in a statistical sense). Only a theory, we do not have proof. IQ tests are designed to produce normal distributions. A test is reliable if it repeatedly gives the same score for the same person: intelligence tests are reliable, and a fairly stable characteristic of the individual over time. A test is valid if it allows correct predictions: IQ tests do predict academic average, however this is almost built-in considering the design of tests. Studies indicate that IQ scores of blacks are higher when the superviser of the test is black than when he is white (motivation? culture? expectations?).

Lesson 45 – Personality traits and the problem of assessment

Phrenology tried to establish personality types based of the shape of the skull. Since then, personality tests have grown into a profitable business. As for IQ: are personality tests reliable and valid? There are two categories of tests: objective and projective tests.

So-called “objective” tests are those in which the score can be computed mechanically. Example: the MMPI (Minnesota Multi Phasic Inventory).

Projective tests, on the contraty, require interpretation from the experts. They are based on the following theory: percipients tend to impose order and organization. In ambiguous situations, where various interpretations exist, the test taker will “project” his inner motivations on the question asked. Examples: Rorschach test (ink blots), TAT (thematic aperception test, series of cards depicting ambiguous scenes on which the subject must imagine a narration), “draw a house-tree-person” test. Projectives tests are interpreted in terms of difference between the profile of the subject and a reference group. This gives information about differences, but no clue as to absolute “values”.

Lesson 46 – Genetic psychology and the Bell curve

Socrates recognized that good soldiers could be bred, making a difference between men of gold, silver, brass and iron. Environment and education count too, but “it is not in bending a spruce that you will make an oak”. This nativistic view raises numerous controversial issues around races and gender differences: do genes influence or even determine math or verbal aptitudes?

There was proposed legislation in the US to restrict immigration of certain group types on the account of their mental defectiveness (ultimate attribution error). Behavior genetic analysis studies the relationship of inbred animals and their behavior: it is possible to inbreed “maze-bright” rats who will have above-normal aptitudes to learn mazes. It does not prove that they are “more intelligent”: they might be more sensitive to hunger during the training process.

Heritability of height is 0.9 to 0.95. This means that by changing the environment, the variance of this characteristic within a given population will remain constant. But it does not predict how a change in environment will impact the average value. For instance, the average height of Japanese has increased a lot since WWII but variance has not changed. Definition of heritability: h² = Vg / Vt where Vg is the variance of the genotype and Vt of the type being measured. Such studies are made by comparing homozygotous twins, heterzygotous twins, brothers parents.

The heritability of IQ ranges from 0.5 to 0.9. Studies show that the average “black” IQ is lower than the average “white” IQ (black and white between quotes because of interracial mixing). However, the average of a phenotype is not determined by its heritability: the heritability of drosophilia eye colour is 100% but depends on the altitude at which the fly is reared. So we know nothing as to how a environmental change could modify the average IQ differences between races.

Lesson 47 – Psychological and biological determinism

Whether evolutionary, skinnerian, biological, we have so far considered psychology as a deterministic process. Back to the old debate of free will. Although we can have some knowledge of the causal laws, it does not mean we know the cause itself. How do we form the concept of causation? David Hume’s constant conjunction theory: we reach the conclusion that A causes B when A and B are constantly conjunct in our experience (in space, time, and nature). We could therefore be mistaking a correlation with a causal relationship.

Scott Thomas Reed made the observation after Hume that we seek causality in externality events only because it is our natural psychology to control our actions. Being able to acting or to restrain from acting is what makes us moral beings. It is on the ground that we have active will that we can hold people responsible for their doings. On the contrary, radical determinism is the thesis according to which our thoughts, language and acts are inextricably determined by the laws of our biological constituents. If there are two views on human and animal psychology, the question of whether we have the possibility of inventiveness and initiative or that this is only the result of a newtonian law will not be answered in a laboratory.

Lesson 48 – Civic development – Psychology, the person and the polis

Psychology has made a lot of progress, but what has it tought us on human nature that we had not learned by the way of philosophy and litterature? There is still no genuinely systematic psychology in the sense that it includes biological, social, ethological, moral, esthetic, political, legal, religious dimensions of human life. The last initiative of this kind was that of Aristotle who systematically measured his remarks in terms of observations and did not only speculate in his armchair.

He therefore recognized the importance of environment and physical world in which our psychology take place. Among those, nothing is more imporant than the political character of the community: the polis. It precedes family and the person itself. If family is understood as a set of obligations of children to parents and vice versa, rules, this exists only within a political context. As for the person, having a personal identity only makes sense within the community. Aristotle considers that humans and animals are quite comparable, except when it comes to the ability to frame universal propositions consistent with a set of rules and laws.

A stateless, lawless, hearthless man therefore cannot fulfill the potentialities of his humanity. He concludes that it is necessary for men to find ourselves within a directing, disciplined, nurturing culture. Young men must fight their excessive passions. Parents must fulfill their office. Therefore the defining task of human beings is to perfect our moral and intellectual virtues. The realized humanity of the individual is the reflection of the polis itself.

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