BiologicalBasis 10 Tests of Intelligence.pdf

Tests of intelligencePSY2304Biological Basis of BehaviourTo h e a r t h e p r e s e n t a t i o n a s y o u g o t h r o u g h t h e s l i d e s , p l e a s e g o t o t h e S l i d e S h o w m e n u and click on “play from start”. You can also start from the slide you...

Tests of intelligencePSY2304Biological Basis of BehaviourTo h e a r t h e p r e s e n t a t i o n a s y o u g o t h r o u g h t h e s l i d e s , p l e a s e g o t o t h e S l i d e S h o w m e n u and click on “play from start”. You can also start from the slide you are on using “play from current slide”. If you want subtitles, then click “always use subtitles”. Finally, you can just look at the slides without hearing me by using the up and down arrows after you open it.What I say in this presentation is either on the slides or in the notes that accompany them (see the notes page in PowerPoint on the View menu). Please click on the slide to advance after I’ve finished speaking or use the forward (and back) arrows to navigate.Lecture 10 It is an important and popular fact that things are not always what they seem. For instance, on the planet Earth, man had always assumed that he was more intelligent than dolphins because he’s achieved so much: the wheel, New York, wars, and so on, whilst all the dolphins had ever done was muck about in the water having a good time. But, conversely, the dolphins believed that they were more intelligent than man for precisely the same reasons. Curiously enough, the dolphins had long known of the impending demolition of Earth, and had made many attempts to alert mankind to the danger. But most of their communications were misinterpreted as amusing attempts to punch footballs, or whistle for titbits, so they eventually gave up and left the Earth by their own means -shortly before the Vogons arrived. The last ever dolphin message was misinterpreted as a surprisingly sophisticated attempt to do a double-backwards somersault through a hoop, whilst whistling the ‘Star-Spangled Banner’. But, in fact, the message was this: “So long, and thanks for all the fish”. In fact, there was only one species on the planet more intelligent than dolphins and they spent a lot of their time in behavioural research laboratories running round inside wheels, and conducting frighteningly elegant and subtle experiments on man.Douglas Adams, The Hitchhiker’s guide to the galaxy, BBC Radio 4 22nd March, 1978 To-day’s questions•Do studies of animal cognition enable us to say which species of animals are most intelligent? •If so, how can we do it, and what is the answer?•In this presentation I focus on the tests most often used in this context. Behavioural correlates of intelligence•Typical suggestion: learning rate –with a fixed task, animals that learn faster must be more intelligent -but contextual variables an issue.•Commonly used example: Hebb-Williams maze (sequence of T-mazes)•More sophisticated example: not one task but “learning how to learn”–Successive reversal–Learning set–Probability learning•Better, a batteryof tests, looking for patterns (Bitterman, 1965), more like the approach to IQ. Examples: Serial Reversal Learning: Mackintosh(1974)+-++--Learn this problem to a criterion of say 90% correct.Then it reverses -learn to same criterion again.It then reverses again -learn to same criterion -and so on.The result? On later reversals the animal makes less errors in acquiring the discrimination. Rate at which this occurs correlated with intelligence? Madingley sheep. Examples: Learning Sets: Harlow (1949)+-++--Learn this problem to a criterion of say 90% correct.Then it changes -learn to same criterion again.It then changes again -learn to same criterion -and so on.The result? On later problems the animal makes less errors in acquiring the discrimination. In extreme cases it makes only 1 error! Can we use the rate of acquisition of this problem as an index of intelligence? Learning sets across species.There are dangers here. Comparisons across species are difficult because it is hard to specify in advance what the optimal conditions for testing any given species would be. This is the problem of contextual variables. Goldfish discrimination 1: They fail to learn.LightsFoodThe Role of Contextual Variables Goldfish discrimination 2: They learn.LightsFoodThe Role of Contextual Variables Contextual variables and learning sets•Herman and Arbeit (1973) found that dolphins had difficulty forming learning sets with visual stimuli but could with auditory stimuli. •Thus, how well an animal forms a learning set may well depend on the type of stimuli used to test them.•The only valid test would be to compare animals with similar sensory and effector capabilities (we’lllook at this approach later). The comparability problem•Howdo we make sure everything except learning is equivalent between animals of different species?–Perceptual difficulty–Mechanical difficulty of response–Level of motivation–Incentive value of rewardBitterman’s suggestion: Control by systematic variationof the confounding factors•Problem: How can we ever explore all variations?•Another solution is to use comparable species, e.g. pigeons and corvids Same vs different discriminationsMatching to sample tasks and oddity from sample tasks (Zentall & Hogan 1974, Wright et al 1988, and many others): responding based on identity/difference if enough exemplars are usedEvidence: Transfer to novel stimuli on the firsttrial. Has been found in Chimps, dolphins and corvids. Was eventually obtained (though only after some considerable effort!) with pigeons, Colombo, Cottle and Frost (2003).Can we use this task to assess the relative intelligence of pigeons and corvids? Pigeons vs. Corvids•This experiment by Wilson, Mackintosh and Boakes (1985) suggests that jackdaws show better transfer to a novel matching problem after training on matching with different stimuli. Note that in this case the jackdaws actually learn more slowly -but show more transfer. •There is also some evidence that corvids (crows, rooks, ravens, magpies and jays) perform better at learning sets than pigeons (Mackintosh, 1988). Recency/Familiarity Explanations•My concern about these studies is that a solution is available to the animal in terms of the recency with which a stimulus has occurred.•So -if they learn to go for the “more recently seen”stimulus -this will transfer across problems. A different strategy that responds to configurations of stimuli will not. Two different methods of solving the problemEither, having studied the sample (top middle) which comes on first, 1. pick the bottom left comparison stimulus because it feels more recent (or more familiar), or 2. pick bottom left because that’s the right response to this configuration of stimuliIt could be that Corvids are biased to use solution 1, whereas pigeons tend to use solution 2, but does that make the corvids more intelligent? Note that there is evidence that pigeons can, after a lot of training, use solution 1, so it might simply be that recency or familiarity information is just less salient for them. Another case of comparability•Language trained vs. non-language trained chimps, Premack (1983), Premack and Premack (1983).•There are some tasks that language trained chimps succeed on that non-language trained chimps cannot pass.•Conversely, there are some tasks that both groups of chimps can do with equal facility. Same / Different Tasks Take 2Language trained chimps could solve these tasks, but non-language trained chimps could not. Interestingly, both sets of chimps could solve successive same/different problems, where one object is shown and then either the same or a different object is shown. Analysis•It’s hard to explain this result away in terms of contextual variables.•It’s also harder to explain in terms of responding based on recency or familiarity.•The extended training that the language trained chimps have received has clearly had an effect. Are they more intelligent as a consequence? •Possibly! References•Bitterman, M. E. (1965). Phyletic differences in learning. American Psychologist, 20, 396-410.•Giurfa, M., & Capaldi, E. A. (1999). Vectors, routes and maps: new discoveries about navigation in insects. Trends in Neurosciences, 22, 237-242.•Giurfa, M., Eichmann, B., & Menzel, R. (1996). Symmetry perception in an insect. Nature, 382, 458-461.•Giurfa, M., Zhang, S. W., Jenett, A., Menzel, R., & Srinivasan, M. V. (2001). The concepts of 'sameness' and 'difference' in an insect. Nature, 410, 930-933.•Macphail, E. M. (1982). Brain and Intelligence in Vertebrates. Oxford University Press. Chapters 1, 2, pp. 207-211 and pp. 277-282•Mackintosh, N. J. (1988). Approaches to the study of animal intelligence. British Journal of Psychology79, 509-525.•Premack, D. (1983). The codes of man and beasts. The behavioral and Brain Sciences, 6, 125-67.•Premack, D. & Premack, A.J. (1983). The mind of an ape. New York, Norton.•Wilson, Bundy, Mackintosh, N. J. and Boakes, R. A. (1985) 'Transfer of relational rules in matching and oddity learning by pigeons and corvids', The Quarterly Journal of Experimental Psychology Section B, 37:4, 313 -332.Reading•Pearce chapters 1 and 14 (3rd edition ) or Pearce (2nd Edition). Chapters 1, and 11.