Reading for today’s lecture

1. Reading for today’s lecture B. M Thorne & T. B. Henley, Connections in the History and Systems of Psychology: Pages 100-107, 211-216, 301-306, 318-323 Dr. Paul Dockree, History of Psychology: PS1203, 2009

2. Early Associationism and Connectionism A natural neural network. The Golgi method of staining brain tissue rendersthe neurons and their interconnecting fibres visible in silhouette Dr. Paul Dockree, History of Psychology: PS1203, 2009

3. Associationism: Learning and Memory • Tabula rasa– “blank slate” • Repeated experiences become habitual patterns (associated ideas and behaviours) that form our character • First associationist – Aristotle • Aristotle proposed three laws of association in memory: • 1. similarity - (cows and horses) • 2. dissimilarity - (hot and cold) • 3. closeness in time and space - (lightning and thunder) • Aristotle’s biological or naturalistic account of how memories are formed: impressions and traces.

4. David Hartley (1705-1757) • Observations on Man (1747/42) • Physiology of Associations: Hartley undertook to define the physiological facts upon which memory images and their sequences depend • application of atomistic Newtonian philosophy to physiological psychology • Vibrations of "white medullary substance of the brain" and miniature vibrations that reach the brain are faint copies or traces of a sensation • Different vibrations become associated upon being repeatedly linked together (re: law of contiguity) • A series of sensations A, B, C, D forms such a pattern in the brain (through miniature vibrations) that later arousal of A alone will set going B, C, D – i.e., the memory images of B, C, D • By Hartley rationale, clusters and sequences of sense impression are the clue to mental life

5. James Mill • James Mill (1773-1836) • Analysis of the Phenomena of the Human Mind (1829/56) • single principle of association contiguity: • the more frequent sensations and idea are paired the higher the strength of association between them. • He reduced mental life down to elementary sensory particles • Perception is a process by which a number of bits are put together to make a whole through additive summation • the process of association of elementary parts is passive and is demonstrated through ‘trains of thought’ James Mill

6. John Stuart Mill John Stuart Mill • John Stuart Mill (1806-1873) • phenomenally precocious (IQ of 190) • a free-thinker (“On the Subjection of Women,” 1869/66) • active conception of mind: “mental chemistry” • JS Mill notes that chemical compounds often represent qualitatively new things, not the summation of single components • In psychology, qualitatively different ideas could be created by combinations of smaller parts

7. Hermann Ebbinghaus (1850-1909) • PhD in Philosophy aged 23! • Gustav Fechner's book Elements of Psychophysics spurred him to conduct his famous memory experiments. Ebbinghaus dedicates his work Fundamentals of Psychology to Fechner. • University of Berlin appointment in 1880 but lost his seat • Ebbinghaus set a new direction in psychology introducing experimental control, and quantitative analysis.

8. Ebbinghaus and Associative Memory • Father of associative memory • Ebbinghaus devised the nonsense syllable: To avoid the pre-established associations of ordinary verbal materials, he devised some 2,300 trigrams: • E.g, "WID" and "ZOF". • Ebbinghaus initial experiments using trigram-word pairs (e.g., ZOF-APPLE, WID-SHOE) • How many iterations of the list was needed to get the participant to errorless performance in learning? Graph showing average number of repetitions required (on y axis) for first errorless reproduction of increasing numbers of nonsense syllables (on x axis) From “Memory: A Contribution to Experimental Psychology” Chapter V Hermann Ebbinghaus (1885)

9. Ebbinghaus’ normal forgetting curve • The forgetting curve exhibits an exponential curve that illustrates how fast we tend to forget the information we have learned. • The sharpest decline is in the first twenty minutes, then in the first hour, and then the curve evens off after about one day.

10. Ebbinghaus and Savings • Another technique that Ebbinghaus used to determined the strength of memory was through a measure he called Savings • So savings becomes a measure of the persistence and efficiency of memory • Effective practice starts with massed practice for fast learning and proceeds to distributed practice later for retention.

11. Ebbinghaus and Savings • Savings upon relearning (even after 100% forgetting) implies subconscious influences. • Ebbinghaus’ savings imply the memorial records are intact but inaccessible • Drawing a parallel between cognitive and psychoanalytic theories

12. Ebbinghaus and the Serial Position Curve Primacy effect Recency effect • The earliest and most recent items are best recalled and the intermediate items are least recalled • On theory that explains this is one of interference between items in the list. • Interference effects are greatest over the middle range and are least at the beginning and at the end of the list.

13. Edward Lee Thorndike (1874-1949) • A very diligent and prodigious American psychologist raised in New England in a Methodist family with a keen interest in science. • Doctoral dissertation in 1898 (aged 24): Animal Intelligence: An Experimental Study of the Associative Process in Animals • Approximately 507 publications! • Basic View of Psychology: the mind is a “connection system”

14. Edward Lee Thorndike (1874-1949) Studied animal behavior using puzzle boxes; formulated the “law of effect,” a precursor to later Skinnerian operant or “instrumental” conditioning paradigm.

15. Four of Thorndike’s cat puzzle boxes

16. Thorndike’s basic data was the learning curve: the time needed to escape in increasing numbers of trials

18. Thorndike formulated two “laws”: 1) “Law of effect”: Behaviors followed by rewards/punishments become more/less frequent The greater the reward or punishment, the greater the change in “connection” between S - R 2) “Law of exercise” A response is more strongly connected to a situation in proportion to the number of times it has been connected to the situation, and to the average vigor and duration of the connection

19. Thorndike and beyond • ‘‘Complex as human life is, it is at bottom explainable by a few principles’’. More pointedly, ‘‘it has been shown that in great measure the intellects and characters of men are explainable by a single law [the law of effect]’’ • Thorndike influenced the beginnings of behaviourism and anti-mentalism • Behaviourism produced some useful principles but., as we will see, historical developments led to opposition to this extreme position and new schools emerged • Association and connectionism are alive today in a different guise: explaining connections of neural networks in animals and in artificial intelligence or computational models that mimic neural networks.