Biases in Visual Attention in Depressed and Nondepressed Individuals

Abstract
The present study utilised a cognitive paradigm to examine attentional biases in mildly depressed persons. Twelve depressed and 12 nondepressed subjects completed an attentional task similar to that employed by MacLeod, Mathews, and Tata (1986). A tachistiscope was used to present subjects with a series of word pairs, each with one word printed above the other. Three types of word pairs were presented: manic-neutral, depressed-neutral, and manic-depressed. Selective attention to one member of a word pair was assessed using ac perception task. Based on cognitive models of depression, it was hypothesised that the depressed subjects would attend more to depressed-content words than to manic- or neutral-content words, whereas the nondepressed subjects would not exhibit any attentional biases. In contrast to these predictions, analyses indicated that whereas the depressed subjects attended equally to depressed-, manic-, and neutral-content words, the nondepressed subjects attended more to manic-content than they did to neutral- or depressed-content words. These results add support to the documentation of evenhandedness in the cognitive functioning of depressed subjects, and of self-sewing biases in nondepressed subjects. The present findings are discussed in terms of a zoom lens model of attention, in which depressed persons attempt to exhaustively process their sensory world, but with a loss of attentional resolution. In contrast, nondepressed individuals attempt to process a more limited portion of their sensory world, but with an increase in attentional power. Finally, directions for future research in this area are offered.