Working memory and intelligence are highly related constructs, but why?

doi:10.1016/j.intell.2008.01.002

Intelligence

Volume 36, Issue 6, November–December 2008, Pages 584-606

https://doi.org/10.1016/j.intell.2008.01.002 Get rights and content

Abstract

Working memory and the general factor of intelligence (g) are highly related constructs. However, we still don't know why. Some models support the central role of simple short-term storage, whereas others appeal to executive functions like the control of attention. Nevertheless, the available empirical evidence does not suffice to get an answer, presumably because relevant measures are frequently considered in isolation. To overcome this problem, here we consider concurrently simple short-term storage, mental speed, updating, and the control of attention along with working memory and intelligence measures, across three separate studies. Several diverse measures are administered to a total of 661 participants. The findings are consistent with the view that simple short-term storage largely accounts for the relationship between working memory and intelligence. Mental speed, updating, and the control of attention are not consistently related to working memory, and they are not genuinely associated with intelligence once the short-term storage component is removed.

Section snippets

Overview of the present studies

Working memory tasks comprise short-term storage plus some sort of processing requirements (Conway et al., 2005, Engle et al., 1999a, Miyake and Shah, 1999) so their correlation with intelligence could be attributed to storage, processing, or both.

The present studies address the contribution of these storage and processing components. It must be emphasized from the outset that the tasks modelled for measuring the constructs of interest follow the mainstream. This underscoring implicates that

Participants

One hundred and eleven participants (70% females) took part in the study to fulfil course requirements. They were recruited at high school (35%) and college institutions (65%). Their mean age was 18.0 (SD = 2.7).

Measures

Short-term memory was measured by three tasks requiring the temporary maintenance of verbal, quantitative, or spatial simple items for latter recall: forward letter span, forward digit span, and Corsi Block.

Forward letter span (FLSPAN) and forward digit span (FDSPAN). Single letters or

Participants

261 university undergraduates (80% females) took part in the study. They participated to fulfil a course requirement. Their mean age was 20.2 (SD = 3.4).

Measures

Short-term memory was measured by forward letter span (FLSPAN), forward digit span (FDSPAN), and dot memory. FLSPAN and FDSPAN were the same as in study 1.

The dot memory task was modelled after Miyake et al. (2001). One five × five grid was displayed for 750 ms at the computer screen. Each grid had between two and seven spaces comprising solid

Participants

Two hundred and eighty-nine university undergraduates (80% females) took part in this study. They participated to fulfil a course requirement. Their mean age was 20.3 (SD = 2.9).

Measures

Short-term memory was measured by forward digit span (FDSPAN) and Corsi Block. Both tasks were the same as administered in study 1.

Working memory was measured by computation span and dot matrix. Computation span was the same task administered in studies 1 and 2. Dot matrix was the same task administered in study 2.

Mental

Cross-validating SEM

In order to cross-validate the results of the SEM analyses, we compute first regression analyses in which a WM composite score was predicted by the remaining composite scores (STM and mental speed — study 1; STM, mental speed, and executive functioning — study 2; STM, mental speed, executive functioning, and controlled attention — study 3). The WM residual score (WM-r) representing the WM variance unpredicted by the predictors is computed. Second, given that executive functioning is highly

The central role of simple short-term storage

Here we considered concurrently several mainstream constructs presumably relevant to understand the large relationship between working memory and intelligence. They were progressively incorporated from study 1 to study 3 in order to gain knowledge in a gradual way. This general discussion begins underscoring the consistencies and inconsistencies across studies.

First, simple short-term storage is a main working memory component. The measures administered in the three studies followed the

Acknowledgements

The research referred to in this article was supported by grants funded by the Spanish Ministerio de Ciencia y Tecnología (Grant No. BSO2002-01455) and by the Spanish Ministerio de Educación y Ciencia (SEJ2006-07890). We would like to thank Miguel Burgaleta, Jesús Privado, and Aida Aguilera for their assistance during testing sessions and tasks programming. We also thank Earl Hunt, Wendy Johnson, Andrew Conway, and one anonymous reviewer for their helpful comments to previous versions of this

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View full text

Working memory and intelligence are highly related constructs, but why?

Abstract

Section snippets

Overview of the present studies

Participants

Measures

Participants

Measures

Participants

Measures

Cross-validating SEM

The central role of simple short-term storage

Acknowledgements

Intelligence

Intelligence

Journal of Experimental Child Psychology

Intelligence

Personality and Individual Differences

Personality and Individual Differences

Neuroimage

Intelligence

Intelligence

Intelligence

Trends in Cognitive Sciences

Journal of Verbal Learning and Verbal Behavior

Intelligence

Intelligence

Intelligence

Intelligence

Journal of Memory and Language

Intelligence

Individual differences in working memory within a nomological network of cognitive and perceptual speed abilities

Journal of Experimental Psychology-General

Working memory and intelligence: The same or different constructs?

Psychological Bulletin

AMOS 5.0, SmallWaters

Is working memory still working?

European Psychologist

Differential Aptitude Test

Structural equation modelling with LISREL, PRELIS, and SIMPLIS: Basic concepts, applications, and programming

Human cognitive abilities

General intelligence and memory span: Evidence for a common neuro-anatomic framework

Cognitive Neurosychology

Simple span tasks, complex span tasks. and cognitive abilities: A re-analysis of key studies

Memory and Cognition

The real relationship between short-term memory and working memory

Memory