The relationship between executive functions and fluid intelligence in schizophrenia

María Roca*, Facundo Manes, Marcelo Cetkovich, Diana Bruno, Agustín Ibáñez, Teresa Torralva, John Duncan

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

23 Citations (Scopus)

Abstract

An enduring question is unity vs. separability of executive deficits resulting from impaired frontal lobe function. In previous studies, we have asked how executive deficits link to a conventional measure of fluid intelligence, obtained either by standard tests of novel problem-solving, or by averaging performance in a battery of novel tasks. For some classical executive tasks, such as the Wisconsin Card Sorting Test (WCST), Verbal Fluency, and Trail Making Test B (TMTB), frontal deficits are entirely explained by fluid intelligence. However, on a second set of executive tasks, including tests of multitasking and decision making, deficits exceed those predicted by fluid intelligence loss. In this paper we discuss how these results shed light on the diverse clinical phenomenology observed in frontal dysfunction, and present new data on a group of 15 schizophrenic patients and 14 controls. Subjects were assessed with a range of executive tests and with a general cognitive battery used to derive a measure of fluid intelligence. Group performance was compared and fluid intelligence was introduced as a covariate. In line with our previous results, significant patient-control differences in classical executive tests were removed when fluid intelligence was introduced as a covariate. However, for tests of multitasking and decision making, deficits remained. We relate our findings to those of previous factor analytic studies describing a single principal component, which accounts for much of the variance of schizophrenic patients' cognitive performance. We propose that this general factor reflects low fluid intelligence capacity, which accounts for much but not all cognitive impairment in this patient group. Partialling out the general effects of fluid intelligence, we propose, may clarify the role of additional, more specific cognitive impairments in conditions such as schizophrenia.

Original languageEnglish
Article number46
Pages (from-to)1-8
Number of pages8
JournalFrontiers in Behavioral Neuroscience
Volume8
Issue numberFEB
DOIs
Publication statusPublished - 24 Feb 2014
Externally publishedYes

Keywords

  • Decision making
  • Executive function
  • Fluid intelligence
  • Frontal lobe
  • Multitasking
  • Schizophrenia

Fingerprint Dive into the research topics of 'The relationship between executive functions and fluid intelligence in schizophrenia'. Together they form a unique fingerprint.

Cite this