Interactice Skills and Individual Differences in Word Generation

1. InteracticeSkills and IndividualDifferences in Word Generation Frédéric Vallée-Tourangeau Psychology Research Unit Kingston University Elizabeth Bolton Carly Burleigh Miles Wrigthman 1

2. Homo Sapiens (the knowing one, the wise one) Homo Habilis (the handy one, the skillful one) Kingston University London 2

3. Homo Über Habilis (HÜH) (the handy one, the skillful one who leverages millennia2 of cumulative technology) 3

4. ‘Habilis’ Reasoning Thinking is exogenised and enriched by the manipulation of artefacts. The artefacts can act as ‘simple’ external storage of information, shoulder some of the computational costs, act as catalysts for productive reasoning. ‘Thinking’ is an emergent product of this interactive system between brain, hands (body), and the world. Kingston University London 4

5. Task The Participants produced new triples by manipulating the dice (not by throwing them). Representation only allowed positive integer data – negative and fractional values are impossible. The integers ranged from 1 to 6, specifying a problem universe containing 63 or 216 possible triples. Control conditions: Procedure and 1-6 5

6. dice isomorph vs. combined control Correct Announcements Dice 27/41 (65%) Procedure 4/21 (19%) 1-6 4/19 (21%) 6

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10. Problem Percentage of B-A-2C answers for each of the 10 problems in the Water Jar group (blue bars) and the Pen & Paper group (open bars) Kingston University London 10

11. Mean proportion of B-A-2C answers for problems 1-5 (shaded bars) and 6-10 (open bars), with standard errors, in the Water Jar and Pen & Paper groups Kingston University London 11

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14. From Maglio et al. (1999): People often adapt their physical environments to take better advantage of cognitive or perceptual skills; so that their mental jobs are easier, faster, or less error-prone. When trying to come up with words In Scrabble, people can either mentally rearrange the letters or physically rearrange the letters…it is reasonable to suppose that it is easier to form words by physically moving the tiles than by simply imagining their rearrangement. Kingston University London 14

15. Each tree = 720 paths 7 letters = 5040 paths Kingston University London 15

16. The vast majority of these strings (paths) are not legal letter combinations. Determining the direction to take at each point can be costly in terms of time and effort. Kingston University London 16

17. These trees configure the problem space. • The physical rearrangement of the letters can morph that space in simpler local representations that facilitate the recognition of areas that spell out admissible words. Kingston University London 17

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21. Maglio et al. (1999) Kingston University London 21

22. fewer words lower frequencies Hard letter set Easy letter set Rearranging the tiles helped generate words with the hard letter set (EMTGPEA)… but had no effect on the easy letter set (RDLOSNA) Kingston University London 22

23. Maglio et al.’s findings reflect the fact that the effectiveness of manipulating the external environment to facilitate reasoning/execution can only be defined in terms relative to task difficulty. Easy tasks can be just as effectively carried out in the head without investing time and effort physically redesigning the external environment to make it more ‘cognitively congenial’ Kingston University London 23

24. In turn, task difficulty can only be characterised in terms relative to the cognitive abilities of the reasoner performing the task. • Proficiency at generating words is determined in part by: • Executive function/search • Visuo-spatial ability (at least with anagram completion – Gavurin, 1967) • Verbal fluency • Maglio et al. did not seek to measure, independently, the participants’ psychometric profile for these abilities. The variance in the effectiveness of the letter rearrangement might have been mediated by these individual differences. Kingston University London 24

25. Objectives of the present study 1. Measure participants’ verbal fluency independent of their performance on the Scrabble task – hypothesis: low-verbal fluency participants should benefit more from rearranging the tiles than high-verbal fluency participants. 2. Explicitly manipulate task difficulty, using an easy letter set, and a hard one. Kingston University London 25

26. Verbal fluency was assessed with the Thurstone (1938) test: participants generated as many words as possible beginning with the letter ‘s’ during a five-minute period, and then as many four-letter words as possible beginning with the letter ‘c’ during a four minute period. Kingston University London 26

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30. Word generation performance with the letter tiles for the easy and hard letter set in the Hands (shaded bars) and No Hands (open bars) experimental conditions for participants classified in the Low Verbal Fluency group (left panel) and in the High Verbal Fluency group (right panel). Kingston University London 30

31. Mean log transformed frequency of words generated by participants in the Hands and in the No Hands condition classified in the low and high frequency groups. Kingston University London 31

32. Conclusions Neuropsychological and neuroimaging evidence implicates the frontal cortex in verbal fluency tasks similar to the one employed in this study. Imaging research maps the neural correlates of cognition when such cognitive activities do not involve physically interacting with an external environment. To the extent that much of cognition is distributed and interactive, neuroimaging research will be limited to mapping neural correlates of relatively unrepresentative cognition. Epistemic and complementary actions may be particularly important in augmenting the cognitive profile of some neuropsychological patients. These actions may be naturally deployed by these patients, and intervention efforts to engineer external restructuring that promote more efficient cognitive operations, might be particularly helpful in compensating for these deficits. Kingston University London 32

33. Conclusions Much of traditional cognitive psychology seeks to profile the human mind in terms of general specifications, such as the capacity of short-term memory or the computational heuristics employed to solve problems or make decisions in probabilistic environments. Clearly there are important individual differences in these system specifications that reflect experience, maturation or innate abilities. In turn, attempts to determine the effectiveness of certain artifacts or spatial reorganizations in aiding reasoners solve problems must be relativised to the difficulty of the task and the cognitive abilities of the reasoners. “(…) the point of informationally structuring space is to reduce the time and memory requirements of cognition, the actual reduction in computation achieved by the various methods (…) does not, in general, lend itself to meaningful quantitative estimation.” Kirsh, 1995, p. 41 Kingston University London 33