Recent studies of brain injured and healthy individuals have provided
empirical support for the theoretical proposition that executive function
and general intelligence are closely associated by demonstrating that
performance on tests of executive function is correlated with general
intellectual ability (g). In the present investigation, the
relationship between performance on the Wechsler Adult Intelligence
Scale-III (WAIS-III), as a measure of g, and performance on
recently developed ecological tests of executive function [i.e.,
Hayling and Brixton, Zoo Map and Key Search sub-tests from the Behavioral
Assessment of the Dysexecutive Syndrome (BADS) battery], was examined
in a sample of 118 severely brain injured individuals. The results
indicated that (a) performance on tests of executive function share
significant variance, and (b) a proportion of that shared variance is
associated with performance on the WAIS-III. Correlations between
conventional measures of executive function (i.e. Trails B and Controlled
Oral Word Association) and WAIS-III were of comparable magnitude to the
correlations between new, ecologically valid executive tests and WAIS-III.
The results provide some support to the notion that tests of executive
function measure non-specific intellectual functions, reminiscent of
g. (JINS, 2007, 13, 90–98.)