Assessment of Frontal Lobe Functioning in Schizophrenia and Unipolar Major Depression

Abstract

This study has used neuropsychological tasks – Wisconsin Card Sort (WCST), Trail Making (TMT) A and B, Verbal Fluency, Digit Span – to compare acute and currently off-medication schizophrenics, patients with unipolar nonpsychotic major depression and healthy controls. Both patient groups differed significantly from healthy controls in their neuropsychological performance. Furthermore there was only little (quantitative) difference between schizophrenics and depressed patients in the frontal lobe associated tasks: WCST, TMT and Verbal Fluency. Depressed patients tended to perform worse than schizophrenics on Digit Span, a task hypothesized to involve other than frontal areas of the brain. Although the group of depressed patients was older than the schizophrenic sample, the effect of age may not totally explain the findings. The results indicate that there do exist disturbances in frontal lobe cognitive functioning in schizophrenia and depression. Symptomatology (SANS/SAPS) and cognitive functioning in the schizophrenic group revealed only a trend for negative symptoms to be associated with worse performance in the WCST, but were significantly correlated with negative as well as positive symptoms on the TMT.

Executive Functioning in Children and Adolescents with Major Depressive Disorder

“…Subsequent power analyses revealed that 4,000 to 43,000 subjects would have been needed for adequate power to detect a difference between groups. These results are largely in contrast to the existing literature in adults with MDD as assessed by a variety of EF tests (Austin et al, 1992; Degl’ Innocenti et al, 1998; Elliot et al, 1996; Franke et al, 1993; Henderson & Welch, 1988; Merriam et al, 1999; Robertson & Taylor, 1985; Trichard et al, 1995). However, these studies included inpatients or outpatients with psychotic/bipolar types of MDD, which likely depict a more severe depressive episode.…”

“…In the adult literature a number of studies provide evidence of executive dysfunction in depressed adults (Channon, 1996; Degl’Innocenti, Argen, & Backman, 1998; Dunkin et al, 2000; Elliott et al, 1996; Fossati, Amar, Raoux, Ergis, & Allilaire, 1999; Franke et al, 1993; M. M. Grant, Thase, & Sweeney, 2001; Henderson & Welch, 1988; Keilip et al, 2001; Merriam, Thase, Haas, Keshavan, & Sweeney, 1999; Oren & Boone, 1991; Robertson & Taylor, 1985; Silberman, Weingartner, & Post, 1983; Trichard et al, 1995).…”

Neuropsychological functioning in inpatients with major depression or schizophrenia

“…Franke et al [6] compared neuropsychological functioning in acute patients with schizophrenia or nonpsychotic major depression, who were not currently receiving medication, to healthy controls. They found only small differences in executive functions, verbal fluency, and focused attention between patients with depression or schizophrenia.…”

Neuropsychological Differences Between First-Admission Schizophrenia and Psychotic Affective Disorders

“…Some reports suggested that subjects with affective disorders perform better overall on neuropsychological tests than subjects with schizophrenia (15). Others found limited differences in performance between the two diagnostic groups (16)(17)(18)(19)(20)(21)(22)(23)(24), especially in subjects with chronic illness or poor outcome (20). Finally, two studies that distinguished between psychotic and nonpsychotic affective disorders reported significant differences between patients with schizophrenia and those with nonpsychotic affective disorders but not between patients with schizophrenia and those with psychotic affective disorders (25,26).…”