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History of Psychology 2007 Lecture 7

History of Psychology 2007 Lecture 7. Professor Gerald C. Cupchik Office: S634 Email: cupchik@utsc.utoronto.ca Office Hours: Wednesdays 1-2 pm Thursdays 12-1 pm T.A: Michelle Hilscher Office: S150 Email: hilscher@utsc.utoronto.ca Office Hours: Thursdays 11-12; 3-4 pm

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History of Psychology 2007 Lecture 7

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  1. History of Psychology 2007 Lecture 7 Professor Gerald C. Cupchik Office:S634 Email: cupchik@utsc.utoronto.ca Office Hours: Wednesdays 1-2 pm Thursdays 12-1 pm T.A: Michelle Hilscher Office: S150 Email: hilscher@utsc.utoronto.ca Office Hours: Thursdays 11-12; 3-4 pm Course Website: www.utsc.utoronto.ca/~cupchik

  2. “Great Developments in the 19th Century”

  3. One of the two main streams in intellectual development contrasted Naturalism versus Anti-Naturalism (Greeks) and The Enlightenment approach to knowledge with that of the German Rationalists. This is essentially a contrast between atomisticand holistic approaches. Today we will consider the implications of the atomistic approach for the development of scientific psychology.

  4. The atomistic stream can be traced back to Greek Naturalism. We will recall the basic tenets of this Materialistic approach: • Monistic – rejects mind/matter distinction • - Matter is fundamental • - Explain all by physical laws • Atomistic – reduce complex to simple • - Reduce matter to smaller parts which are accepted as fundamental • Reduce quality to quantity • - Qualities such as red and blue, sweet and sour, warm and cold are reduced to wavelengths of light, chemical reactions in receptors and transmission of molecular motion. • - Qualities are secondary, to be restated eventually as quantitative differences in the behaviour of a single primary substance.

  5. Reduce function to structure • - Organisms behave as if trying to maintain themselves, seeking appropriate food, defending against danger, selecting mates. - These are organismic functions with purpose. - From a materialist viewpoint, purpose cannot exist in nature. - Purposive functions must be explained in terms of structures which have evolved (through natural selection) in such a way that the species is preserved. - The structure is inherited or built up through learning (e.g., structure of the eye) - The fine distinctions of logicians refer to structural relations among cortical elements.

  6. This approach was revived during the Renaissance by scholars in Italy and elsewhere who focused on nature in the absence of dogma as the real authority; the new naturalism. It was accompanied by major scientific revolutions including the new heliocentric theory proposed by Copernicus (1473-1543) and refined by Kepler’s (1571-1630) laws of planetary (elliptical) motion, Galileo’s (1564-1642) dynamics of moving bodies, and Newton’s (1642-1727) principle of gravitation, laws of motion, and analysis of white light as a mixture of colours.

  7. PHYSIOLOGY Biological science started as medical science which, with the Greeks and before them, was a mixture of anatomy, surgery and knowledge of medicinal plants, supplemented by magic and other dogmatic principles. The law forbade the dissection of human bodies so that advances in the correct knowledge of anatomy depended on animal dissection. So physiological knowledge was held back by ignorance of anatomy. Major Figures in the Development of Physiology 1. Hippocrates (ca. 460-370 BC) – He was the “father of medicine” who showed rare objectivity toward medical facts but he lacked anatomical knowledge. 2. Galen (ca. 129-199 AD) – He was a good observer and limited experimenter. He: (i) localized the mind in the brain, and (ii) distinguished between sensory and motor nerves, an idea which was lost and rediscovered in the 19th century.

  8. In the 16th century dissection of the body was being practiced, although with opposition from the Church. Both Leonardo da Vinci and Michelangelo performed dissection. In other words, artists were one step ahead of the scientists. 3. Andreas Vesalius (1514-1564) – Born in Belgium. He marked the triumph of observation over dogma in medicine. By 1537 he was lecturing to large audiences in anatomy. It took another century to pick up on his work of which the church disapproved. Vesalius was born into a family long associated with the medical care of the imperial dynasty, most notably being his father who was the pharmacist for Charles V of Germany. From an early age, Vesalius showed an inclination to follow in the family tradition through his dissection of dead birds and mice. He studied at the University of Leuven from 1530 until 1533, when he began his studies at the University of Paris under Jacobus Sylvius and Johann Guinter.

  9. At the outbreak of the war between France and the Holy Roman Empire in 1536, Vesalius returned home to complete his studies at the University of Leuven, where he received his medical degree in 1537. In the autumn of 1537, Vesalius enrolled in the medical school of the University of Padua, and received his doctorate of medicine shortly thereafter. Upon his graduation, he was immediately offered the chair of Surgery and Anatomy (explicator chirurgiae) at Padua, where he began giving public lectures. His innovative lectures and course plans were unique for two reasons. First, he performed his own dissections rather than reading aloud while a demonstrator did the dissection and second, because he used drawings to aide his teaching. These drawings became an integral part in his teaching, and later in his published works.

  10. Soon thereafter, Vesalius became interested in the validity of Galen's findings, and began his study on human anatomy and his major work, De humani corporis fabrica. In 1539, a Paduan judge became interested in Vesalius' work, and made bodies of executed criminals available for dissection. His collection of detailed anatomical diagrams grew, many were produced by artists and were of better quality than previous diagrams. His diagrams became known as the first accurate set to be produced.

  11. 4. William Harvey (1578-1657) – He did for physiology what Vesalius had done for anatomy. Through observation and experiment, he worked out the exact connection of the cavities of the heart with each other and with the lungs, the arteries, and the veins. The connections and the valves showed the way the blood must be flowing. Harvey’s work appears very modern: he experimented and obeyed the injunction of the Paduan anatomists to see for oneself. ‘I profess to learn and teach anatomy not from books but from dissections,’ he declared, ‘not from the tenets of Philosophers but from the fabric of Nature.’ But that is only half true; certainly he looked for himself (and without the aid of the microscope), but he saw through Aristotelian spectacles. Harvey did not, as sometimes supposed, conceive of the body in a ‘modern’ mechanical fashion: it was too a machine, but was moved by vital forces.

  12. In discussing the circulation, he wrote, drawing on traditional macrocosm/microcosm correlations, that it was to transport life-giving blood to the periphery and then to return it to the heart where it could be re-enlivened. There was no burst of good work in scientific physiology right after Harvey nor in fact in the 18th century. In the 19th century there was a chain reaction, one discovery making another possible, one enthusiasm setting off another. This work in the 19th century laid the foundation for experimental physiological psychology. Interestingly, this kind of work appealed more to the Germans than to the English or French scholars. Why did scientific psychology begin in Germany? It began as taxonomic description. While we associate Germans with a phenomenological approach, its real foundation has to do with description, classification and induction which contrasts with the mathematical and deductive approaches. This requires the attitude of a painstaking and methodological culture.

  13. Biology was not yet ready to lend itself to great generalizations. So the Germans took up the task of collecting observational facts that were sound, detailed, conscientious and thorough. So psychology joined the family of sciences because the Germans had faith in collecting data and welcomed biology into the circle of science. The French and English hesitated because biology did not fit with the scientific pattern set by physics. The holistic attitude of the Germans saved the day.

  14. Physiology in the First Half of the 19th Century There are 9 major developments between 1800 and 1850 all but two of which belong as much in the history of physiology. None of these findings were made by scholars who considered themselves to be psychologists. 1. Sensory and Motor Nerves Sir Charles Bell (1774-1842) re-discovered the fact of the differences between sensory and motor nerves in the spinal cord – that they were anatomically and functionally discrete. Rule: The posterior or dorsal roots of the spinal cord contain only sensory fibres and the anterior roots only motor fibres. Bell later showed that some cranial nerves are entirely sensory, some entirely motor, and some mixed. He later established the law of forward direction in the nervous system which holds that conduction in a nerve normally flows in one direction.

  15. The significance of this work: We could no longer regard the nerves as transmitting both the powers of sensation and of motion. [Note that Francois Magendie made the same discovery independently but later and he had the more convincing experiment. He was also a notorious vivisector whose shocking dissections of live animals led in England to anti-vivisection laws.]

  16. 2. Reflex Action This research was basic to the conception of reflex action and the reflex arc. Bell published the results privately in 1811 in a pamphlet (100) for his friends and colleagues. In 1751, Robert Whytt, a Scot (1714-1766), described experiments with frogs showing that the spinal cord was both necessary and sufficient for many automatic movements which occur in response to stimulation when the spinal cord is severed from the brain. He distinguished between: i. Voluntary movement, which is an act of will ii. Involuntary spontaneous movement which occurs instantaneously with no time for the exercise of reason but it was dependent on sensation in the nervous system.

  17. M. Hall (1790-1857) distinguished between conscious voluntary movement and involuntary movement dependent only on the spinal cord, independent of the brain and consciousness. The unconscious reflexes were relegated to physiology. The new physiological psychology, which got under was around 1850, was organized as a psychology of conscious voluntary action and reaction time. The distinction broke down with (1) Pavlov’s demonstration that unconscious movements can be learned (conditioned reflex) and (2) Freud’s discovery of unconscious motives and thinking.

  18. 3. Electrical Nature of the Nerve Impulse The 17th century furnished a means for generating static electricity and the 18th century made it more available by the invention of the Leyden Jar (1745). Galvanibegan experiments on the stimulation of frog’s legs by electric discharges. In 1791 he produced a kick in the frog’s leg with an electric charge and concluded that animal tissues generate electricity. Volta showed that this kind of electricity electricity can be had without animal tissues by creating an inorganic battery. He thought that he had disproved animal electricity.

  19. du Bois-Reymond developed a theory of the polarization of animal tissues in 1848-49. He argued that muscles and nerves consist of electrically charged particles with a positive charge on one face and a negative charge on the opposite one, oriented like a magnet. This relates to the modern concept of polarization. He brought the nervous impulse out of the mystical realm of animal spirits and into material science suggesting to Helmholtz that the activity of the impulse may not be instantaneous but finite and measurable.

  20. 4. Velocity and Conduction of the Nerve Impulse It had been supposed that the velocity of the nervous impulse was so rapid as to be practically immeasurable. i. 9000 ft/min ii. 32,400 ft/min iii. 57,600 ft/sec which is 60 times the velocity of light. Haller’s estimate of 150 ft/sec is close to the truth which is 3-400 ft/sec depending on the diameter of the conducting fibre.

  21. It is important for psychology to determine that transmission is not instantaneous but relatively slow. • To separate the movement of a finger in time from the event of will that caused it was in a sense to separate the body from the mind. • So bodily motion becomes part of a series of events and this contributed to the materialist view of the psycho-physical organism that was the essence of 19th century science. • Other developments: • Electrical depolarization – Bernstein (1866) • Wave of negativity passing along the nerve. • All or none principle – Bowditch (1871) • -A nerve fibre supplies the energy for an impulse and is completely discharged when excited.

  22. 5. Specific Energy of Nerves Müller (1826) – The central principle is that (1) we are directly aware, not of the object, but of our sensory nerves themselves. So the idea is that the mind is the result of a reaction excited in the eye or brain and not of anything received. The operation of the mind is determined by the kinds of senses that we have. (2) There are five kinds of nerves (specificity); each kind imposes its specific quality on the mind. So the quality of sensation depends not upon the nature of the cause but upon the nature of the nerve which the cause affects. Now we know that qualitative differences lie not in the nerve excitation themselves but rather different central effects.

  23. 6. Phrenology Phrenology relates to the problem of where the mind is located in the body. It was not commonly held that the mind was in the brain. Phrenology tried to establish that: (1) The brain is the organ of the mind. (2) Particular parts of the brain are associated with separate mental faculties.

  24. HISTORY Aristotle: Mind  Egyptians: Thought  ; Judgment  Pythagoras: Seat of mind and intellect  Plato: Seat of mind     Alexandrian anatomists: Seat of mind  Also brain Descartes: Soul  in the entire body but specifically the pineal gland; did not identify the brain with the mind. The modern idea of the brain as the seat of the mind emerged in the 19th century. It was prepared in the late 18th century by Jean Baptiste Pinel. After Pinel, possession was treated as a disease. To recognize the mind as subject to disease orients us towards the idea of the mind’s dependence on the body, the usual seat of disease.

  25. A Little History The first humane impulse of any considerable importance in this field seems to have been aroused in America. In the year 1751 certain members of the Society of Friends (Quakers) founded a small hospital for the insane, on better principles, in Pennsylvania. To use the language of its founders, it was intended “as a good work, acceptable to God.‘” Twenty years later Virginia established a similar asylum, and gradually others appeared in other colonies. But it was in France that mercy was to be put upon a scientific basis, and was to lead to practical results which were to convert the world to humanity. In this case, as in so many others, from France was spread and popularized not only the scepticism which destroyed the theological theory, but also the devotion which built up the new scientific theory and endowed the world with a new treasure of civilization.

  26. In 1756 some physicians of the great hospital at Paris known as the Hotel-Dieu protested that the cruelties prevailing in the treatment of the insane were aggravating the disease; and some protests followed from other quarters. Little effect was produced at first; but just before the French Revolution, Tenon, La Rochefoucauld-Liancourt, and others took up the subject, and in 1791 a commission was appointed to undertake a reform. By great good fortune, the man selected to lead in the movement was one who had already thrown his heart into it - Jean Baptiste Pinel. In 1792 Pinel was made physician at Bicetre, one of the most extensive lunatic asylums in France, and to the work there imposed upon him he gave all his powers. Little was heard of him at first. The most terrible scenes of the French Revolution were drawing nigh; but he laboured on, modestly and devotedly - apparently without a thought of the great political storm raging about him.

  27. His first step was to discard utterly the whole theological doctrine of ``possession,'' and especially the idea that insanity is the result of any subtle spiritual influence. He simply put in practice the theory that lunacy is the result of bodily disease. It is a curious matter for reflection, that but for this sway of the destructive philosophy of the eighteenth century, and of the Terrorists during the French Revolution, Pinel's blessed work would in all probability have been thwarted, and he himself excommunicated for heresy and driven from his position. Doubtless the same efforts would have been put forth against him which the Church, a little earlier, had put forth against inoculation as a remedy for smallpox; but just at that time the great churchmen had other things to think of besides crushing this particular heretic: they were too much occupied in keeping their own heads from the guillotine to give attention to what was passing in the head of Pinel. He was allowed to work in peace, and in a short time the reign of diabolism at Bicetre was ended.

  28. What the exorcisms and fetiches and prayers and processions, and drinking of holy water, and ringing of bells, had been unable to accomplish during eighteen hundred years, he achieved in a few months. His method was simple: for the brutality and cruelty which had prevailed up to that time, he substituted kindness and gentleness. The possessed were taken out of their dungeons, given sunny rooms, and allowed the liberty of pleasant ground for exercise; chains were thrown aside. At the same time, the mental power of each patient was developed by its fitting exercise, and disease was met with remedies sanctioned by experiment, observation, and reason. Thus was gained one of the greatest, though one of the least known, triumphs of modern science and humanity.

  29. Phrenologyemerged due to the work of Franz Joseph Gall (1758-1828) who was an anatomist. As a schoolboy, he observed a relationship between mental qualities of his school mates and shapes of their heads (e.g., prominent eyes and good memories). His doctrine gained public attention and the church tried to have the government of Austria force him to discontinue his lectures. He moves to France!

  30. The Basic Propositions 1. Phrenologists must show conformation of exterior to interior skull and brain. 2. The mind can be meaningfully analyzed into a number of faculties or functions. 3. Faculties and powers of the mind are localized in the brain and an excess of any faculty is correlated with an enlargement of the corresponding place in the brain. So a protrusion of the brain would indicate an excess in the particular faculty. Phrenology flourished for a century. There were 29 societies in Great Britain and several journals. But it was never accepted as a science even though it retained popular appeal even though knowledge of the brain physiology rendered it impossible.

  31. The importance of phrenology lies in its effect on scientific thought of the period. From a negative standpoint: (1) Physiologists disbelieved the relation of the skull to the brain. (2) Philosophers objected to analysis of the mind into faculties because it violated the principle of unity of mind. But, while essentially wrong, it furthered scientific thought by: (1) Establishing the brain as the organ of the mind. (2) It suggested localization of function in the brain. It mediated between the Cartesian concept of an unsubstantiated soul and the concept of mere material neural function. Phrenology was wrong only in detail.

  32. 7. Physiology of the Brain A. The French physiologist Bichat (1771-1802) assumed a connection between the mind and brain. He felt that the brain is the centre for intelligence, perception, imagination and judgment but that emotions are centred in the internal organs. Gall’s specific psychophysiology made a radical but less extreme view seem conservative. He prompted Pierre Flourens to associate different functions with the cerebrum, cerebellum, medulla and spinal cord. So Flourens mediated between the too vague tradition of Descartes and the too specific doctrine of the phrenologists. His conclusions were based on experimentation.

  33. Moment in scientific wisdom. He said “There is a great secret behind being brief. That is to be clear.” Flourens substituted carefully planned experiments for nature’s experiments that occur in accidental lesions and disease. Using animals, his method was the extirpation of parts and he looked for a correlation between brain area and function. For example, the function of the cerebral cortex is willing, judging, and seeing. He distinguished six parts. He also distinguished “action propre” from “action commune”. “Action propre” or exact localization implies a special function for each of the 6 parts (in the direction of Gall). “Action commune” or field theory implies a general function such that the removal of one part reduces the energy of every other. This is related to the unity of mind which philosophers had contended.

  34. B. The improvement of the microscope around 1830 led to histological research. Luigi Rolando first thought (1824) of cutting thin sections of brain tissue chemically hardened for microscopic examination. This procedure was important because Flourens had divided the brain into a few gross parts each with its own function. But he didn’t analyze further within each part. The histological work led the brain to be considered as composed of an almost infinite number of separate cells which connect in a complicated network.This view of the brain bore a close resemblance to the picture of the mind adhered to by the Associationists, the dominant psychology of the period which held that the mind consisted of an infinitude of ideas. These ideas are bound together into more complex ideas by association, just as the nerve cells are connected by fibres. In sum, the new knowledge of the division of the brain into many tiny interconnected units implied that further separation of localized mental functions should be sought. Later research localized functions such as hearing, somesthesis, and sensation.

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