Elsevier

Intelligence

Volume 46, September–October 2014, Pages 107-121
Intelligence

Relations between speed, working memory, and intelligence from preschool to adulthood: Structural equation modeling of 14 studies

https://doi.org/10.1016/j.intell.2014.05.013Get rights and content

Highlights

  • Fluid intelligence develops in four cycles, with two phases in each.

  • Cycle transitions are predicted by speed and phase transitions by working memory.

  • Modeling of 14 studies validated the alternating speed–Gf and WM–Gf cycles.

  • An expanding executive control core drives changes within each cycle.

Abstract

We posit that fluid intelligence (Gf) develops in four cycles, with two phases in each cycle, each distinctly connected with changes in processing speed and working memory. New representational units emerge in the first phase of each cycle at 2–4 (representations), 6–8 (inference based concepts), and 11–13 years (principles) and they are integrated into wider systems in the second phase, at 4–6, 8–11 and 13–16 years. We hypothesized that cycle transitions are better predicted by speed and phase transitions by working memory. To test this hypothesis several published studies were selected which measured speed, WM, and Gf at one or more of the age phases concerned. In structural equation models applied on each phase speed was regressed on age, working memory was regressed on age and speed, and Gf was regressed on all three. In line with the hypothesis, in the first phase of each cycle the speed–Gf relations were high and WM–Gf relations were low; this pattern was inverted in the second phase. The role of executive processes strengthened in the second phase of all cycles. The implications for developmental and differential theories of intelligence are discussed.

Section snippets

Studies and results

To facilitate presentation, we present the various studies according to the age phases covered, following the succession of cycles and phases as outlined in the introduction. The age phase covered and the tasks used by each study are summarized below and in Table 1. We refer the interested reader to the original publications for more information. Fit indices and structural relations between constructs in each study are shown in Table 2. To facilitate inspection of the main trends found, Fig. 2

Discussion

It is notable that our predictions about the recycling patterns of speed–Gf and WM–Gf relations were borne out by so many different studies, especially if the structural equivalence of these studies is taken into account (see Fig. 2). These patterns provide support for an integrated developmental–differential theory of intelligence that would explicate why Gf changes coalesce with speed at the beginning of developmental cycles and with WM changes at the end. Gf undergoes three types of change:

Acknowledgement

Special thanks are due to Andrea Astle, Carleton University, Canada, Nicholas R. Burns and Ted Nettelbeck, University of Adelaide, Australia, David J. Francis, University of Houston, USA, Sandra Hale, Washington University in St. Louis, USA, Robert V. Kail, Purdue University, USA, Andrew N. Meltzoff, University of Washington, USA, Carol A. Miller, Pennsylvania State University, USA, and J. Bruce Tomblin, University of Iowa, USA, for generously contributing their data files in forms appropriate

References (59)

  • M. Luciano et al.

    Perceptual speed does not cause intelligence, and intelligence does not cause perceptual speed

    Biological Psychology

    (2005)
  • L.T. Miller et al.

    Intelligence, reaction time, and working memory in 4- to 6-year-old children

    Intelligence

    (1996)
  • J. Pascual-Leone

    A mathematical model for the transition rule in Piaget's developmental stages

    Acta Psychologica

    (1970)
  • K.J. Riggs et al.

    Changes in the capacity of visual working memory in 5- to 10-year-olds

    Journal of Experimental Child Psychology

    (2006)
  • F.V. Rijsdijk et al.

    The genetic basis of the relation between speed-of-information-processing and IQ

    Behavioural Brain Research

    (1998)
  • L. Stankov et al.

    Mental speed is not the ‘basic’ process of intelligence

    Personality and Individual Differences

    (1997)
  • L. Swanson et al.

    Working memory, short-term memory, and naming speed as predictors of children's mathematical performance

    Intelligence

    (2007)
  • T.P. Alloway et al.

    Verbal and visuospatial short-term and working memory in children: Are they separable?

    Child Development

    (2006)
  • M. Anderson

    Intelligence and development: A cognitive theory

    (1992)
  • M. Anderson

    Annotation: Conceptions of intelligence

    Journal of Child Psychology and Psychiatry

    (2001)
  • P.M. Bentler

    EQS 6 structural equations program manual

    (2006)
  • D. Bernstein et al.

    Hindsight bias and developing theories of mind

    Child Development

    (2007)
  • J. Bruner

    Studies in cognitive growth

    (1966)
  • J.B. Carroll

    Human cognitive abilities: A survey of factor-analytic studies

    (1993)
  • R. Case

    Intellectual development: Birth to adulthood

    (1985)
  • N. Cowan et al.

    Seven- year-olds allocate attention like adults unless working memory is overloaded

    Developmental Science

    (2010)
  • N. Cowan et al.

    What do estimates of working memory capacity tell us?

  • T.R. Coyle et al.

    Processing speed mediates the development of general intelligence (g) in adolescence

    Psychological Science

    (2011)
  • S. Dehaene

    The number sense: How the mind creates mathematics

    (1997)
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