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Executive function and fluid intelligence after frontal lobe lesions.

Roca M, Parr A, Thompson R, Woolgar A, Torralva T, Antoun N, Manes F, Duncan J - Brain (2009)

Bottom Line: These deficits appear on a background of reduced fluid intelligence, best measured with tests of novel problem solving.Deficits are not fully explained by fluid intelligence and the data suggest association with lesions in the right anterior frontal cortex.Understanding of frontal lobe deficits may be clarified by separating reduced fluid intelligence, important in most or all tasks, from other more specific impairments and their associated regions of damage.

View Article: PubMed Central - PubMed

Affiliation: Institute of Cognitive Neurology (INECO), Buenos Aires, Argentina.

ABSTRACT
Many tests of specific 'executive functions' show deficits after frontal lobe lesions. These deficits appear on a background of reduced fluid intelligence, best measured with tests of novel problem solving. For a range of specific executive tests, we ask how far frontal deficits can be explained by a general fluid intelligence loss. For some widely used tests, e.g. Wisconsin Card Sorting, we find that fluid intelligence entirely explains frontal deficits. When patients and controls are matched on fluid intelligence, no further frontal deficit remains. For these tasks too, deficits are unrelated to lesion location within the frontal lobe. A second group of tasks, including tests of both cognitive (e.g. Hotel, Proverbs) and social (Faux Pas) function, shows a different pattern. Deficits are not fully explained by fluid intelligence and the data suggest association with lesions in the right anterior frontal cortex. Understanding of frontal lobe deficits may be clarified by separating reduced fluid intelligence, important in most or all tasks, from other more specific impairments and their associated regions of damage.

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Experiment 2. Lesion overlap for 6 patients with worst average residual (performance adjusting for fluid intelligence) across Go–no go, Proverbs, Hayling, Hotel and Faux Pas tests. Left: overlap projected to brain surface; colour scale shows number of affected patients. Right: slice illustrating maximum overlap; coordinates in MNI space.
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Figure 5: Experiment 2. Lesion overlap for 6 patients with worst average residual (performance adjusting for fluid intelligence) across Go–no go, Proverbs, Hayling, Hotel and Faux Pas tests. Left: overlap projected to brain surface; colour scale shows number of affected patients. Right: slice illustrating maximum overlap; coordinates in MNI space.

Mentions: In a further analysis we employed a lesion overlap method for more targeted examination of deficits beyond those explained by fluid intelligence. First, we examined the relationship between such deficits in the five tasks where they were found (Go–No go, Proverbs, Hayling, Hotel, Faux Pas). For each task, scores for each patient and control were converted to residuals after adjusting for fluid intelligence (Figs 3 and 4, vertical distances from the regression line). Residuals in the five tasks were then correlated, for a total of 10 correlations between all possible task pairs (see Supplementary Table). Combining the data for patients and controls, all 10 correlations were positive (median = 0.30, range = 0.03 to 0.52). For patients alone, 7/10 correlations were positive (median = 0.14, range = −0.36 to 0.45), while for controls alone 9/10 were positive (median = 0.28, range = −0.03 to 0.47). Together, these results suggest that, across the five tasks, deviations from the score predicted by fluid intelligence may be traced at least in part to some common factor. For each patient, accordingly, we obtained a mean residual across the five tasks (or fewer for patients with missing data), and examined lesion overlap for the six patients with the greatest negative value (i.e. greatest deficit beyond the prediction from fluid intelligence). The result (Fig. 5) provides a suggestion of selective association with anterior frontal lesions, especially in the right hemisphere.Figure 5


Executive function and fluid intelligence after frontal lobe lesions.

Roca M, Parr A, Thompson R, Woolgar A, Torralva T, Antoun N, Manes F, Duncan J - Brain (2009)

Experiment 2. Lesion overlap for 6 patients with worst average residual (performance adjusting for fluid intelligence) across Go–no go, Proverbs, Hayling, Hotel and Faux Pas tests. Left: overlap projected to brain surface; colour scale shows number of affected patients. Right: slice illustrating maximum overlap; coordinates in MNI space.
© Copyright Policy - creative-commons
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2801324&req=5

Figure 5: Experiment 2. Lesion overlap for 6 patients with worst average residual (performance adjusting for fluid intelligence) across Go–no go, Proverbs, Hayling, Hotel and Faux Pas tests. Left: overlap projected to brain surface; colour scale shows number of affected patients. Right: slice illustrating maximum overlap; coordinates in MNI space.
Mentions: In a further analysis we employed a lesion overlap method for more targeted examination of deficits beyond those explained by fluid intelligence. First, we examined the relationship between such deficits in the five tasks where they were found (Go–No go, Proverbs, Hayling, Hotel, Faux Pas). For each task, scores for each patient and control were converted to residuals after adjusting for fluid intelligence (Figs 3 and 4, vertical distances from the regression line). Residuals in the five tasks were then correlated, for a total of 10 correlations between all possible task pairs (see Supplementary Table). Combining the data for patients and controls, all 10 correlations were positive (median = 0.30, range = 0.03 to 0.52). For patients alone, 7/10 correlations were positive (median = 0.14, range = −0.36 to 0.45), while for controls alone 9/10 were positive (median = 0.28, range = −0.03 to 0.47). Together, these results suggest that, across the five tasks, deviations from the score predicted by fluid intelligence may be traced at least in part to some common factor. For each patient, accordingly, we obtained a mean residual across the five tasks (or fewer for patients with missing data), and examined lesion overlap for the six patients with the greatest negative value (i.e. greatest deficit beyond the prediction from fluid intelligence). The result (Fig. 5) provides a suggestion of selective association with anterior frontal lesions, especially in the right hemisphere.Figure 5

Bottom Line: These deficits appear on a background of reduced fluid intelligence, best measured with tests of novel problem solving.Deficits are not fully explained by fluid intelligence and the data suggest association with lesions in the right anterior frontal cortex.Understanding of frontal lobe deficits may be clarified by separating reduced fluid intelligence, important in most or all tasks, from other more specific impairments and their associated regions of damage.

View Article: PubMed Central - PubMed

Affiliation: Institute of Cognitive Neurology (INECO), Buenos Aires, Argentina.

ABSTRACT
Many tests of specific 'executive functions' show deficits after frontal lobe lesions. These deficits appear on a background of reduced fluid intelligence, best measured with tests of novel problem solving. For a range of specific executive tests, we ask how far frontal deficits can be explained by a general fluid intelligence loss. For some widely used tests, e.g. Wisconsin Card Sorting, we find that fluid intelligence entirely explains frontal deficits. When patients and controls are matched on fluid intelligence, no further frontal deficit remains. For these tasks too, deficits are unrelated to lesion location within the frontal lobe. A second group of tasks, including tests of both cognitive (e.g. Hotel, Proverbs) and social (Faux Pas) function, shows a different pattern. Deficits are not fully explained by fluid intelligence and the data suggest association with lesions in the right anterior frontal cortex. Understanding of frontal lobe deficits may be clarified by separating reduced fluid intelligence, important in most or all tasks, from other more specific impairments and their associated regions of damage.

Show MeSH
Related in: MedlinePlus