Intelligence

Manuel Gerardo Saldivar, M.Ed.

Higher-level Cognition

Fall 2008

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Outline

Neisser, U., Boodoo, G., Bouchard, J. R. Jr., Boykin, A. W., Brody, N., Ceci, S. J., Halpern, D. F., Loehlin, J. C., Perloff, R., Sternberg, R. J., & Urbina, S. (1996, February). Intelligence: Knowns & unknowns. American Psychologist, 51(2), 77-101.

Gray, JR, Chabris, CF, & Braver, TS (2003). Neural mechanisms of general fluid intelligence. Nature Neuroscience, 6, 316-322.

Conway, ARA, Kane, MJ, & Engle, RW (2003). Working memory capacity and its relation to general intelligence. Trends in Cognitive Sciences, 7, 547-552

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A few metaphors

Isaiah Berlin: the hedgehog and the fox

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A few metaphors

Isaiah Berlin: the hedgehog and the fox

Intelligence is..?

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A few metaphors

Isaiah Berlin: the hedgehog and the fox

Intelligence is..?

Uni-dimensional ------------ Multi-dimensional

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A few metaphors

Isaiah Berlin: the hedgehog and the fox

Intelligence is..?

Uni-dimensional ------------ Multi-dimensional

Fixed ---------------------------------------- Unfixed

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Neisser, et. al.

Intelligence: Knowns & unknowns

• Origins of intelligence testing and psychometrics• Multiple forms of intelligence• Cultural variation – how to define intelligence?

– Intelligence: predictor variable or outcome variable?

• Genetic roots of intelligence

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Neisser, et. al.

Intelligence: Knowns & unknowns (cont.)

• Group differences in intelligence– Nature vs. nurture

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Gray, et. al.

Neural mechanisms of general fluid intelligence

• Focuses on gF (general fluid intelligence): “is a major dimension of individual differences and refers to reasoning and novel problem-solving ability” (p. 316)– Related to meta-cognition, working memory, and

attentional control– Neural substrate of gF includes PFC

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Gray, et. al.

Neural mechanisms of general fluid intelligence

• Hypothesis1: there is “a covariation of gF with brain activity in regions that are critical for attentional control” (p. 316)

• Hypothesis2: “the relationship between gF and brain activity should be stronger under high-interference conditions than under low-interference conditions” (p. 316)

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Conway, et. al.

Working memory capacity and its relation to general intelligence

• Focuses on WMC (working memory capacity): “the ability to remember things in an immediate-memory task (a task with no delay between the end of the presentation of items to be recalled and the period of recall itself)” (Cowan, p. 3).

Cowan, N. (2005). Working memory capacity. New York: Psychology Press.

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Conway, et. al.

Working memory capacity and its relation to general intelligence

• Spearman’s g: the ‘general intelligence factor’

Spearman, C. (1904). “General intelligence," objectively determined and measured. American Journal of

Psychology, 15, 201-293.

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Conway, et. al.

• Latent variables cannot be directly measured– Ex.: math aptitude

• Factor analysis allows for the measurement of ‘principal components’ and their relation to underlying constructs

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Conway, et. al.

Conclusions:• WMC accounts for 1/3 to 1/2 of the variance of g• “WM span tasks… require the active

maintenance of information in the face of concurrent processing and interference… an executive attention-control mechanism [combats] interference” (p. 551)

• This executive module is located in the PFC

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Slides available for download:

www.SaldivarResearch.com