Cognitive vulnerability and frontal brain asymmetry: common predictors of first prospective depressive episode

Abstract

The hopelessness theory of depression proposes that individuals with a depressogenic cognitive style are more likely to become hopeless and experience depression following negative life events. Although the neurophysiological underpinnings of cognitive style remain speculative, research indicates that decreased relative left frontal brain electrical activity holds promise as a traitlike marker of depression. This begs the question: Do measures of depressogenic cognitive style and resting frontal brain asymmetry index a common vulnerability? The present study provides preliminary support for this hypothesis. At baseline assessment, increased cognitive vulnerability to depression was associated with decreased relative left frontal brain activity at rest in individuals with no prior history of, or current, depression. Following baseline assessment, participants were followed prospectively an average of 3 years with structured diagnostic interviews at 4-month intervals. Both cognitive vulnerability and asymmetric frontal cortical activity prospectively predicted onset of first depressive episode in separate univariate analyses. Furthermore, multivariate analyses indicated that cognitive vulnerability and frontal asymmetry represented shared, rather than independent, predictors of first depression onset.

Figures

Figure 1

(A) Scatter plot of the correlation between resting frontal asymmetry [ln(mean of F4/F8)-ln(mean of F3/F7)] and CSQ-N scores. Lower EEG asymmetry scores reflect reduced relative left-frontal activity. Higher CSQ-N scores reflect greater cognitive vulnerability for depression. (B) Topographic map of the distribution of correlations between frontal asymmetry and CSQ-N scores. As predicted, the relation between frontal asymmetry and CSQ-N scores is specific to the frontal region (r values for non-frontal indices>.26).