Attentional resources in major depression

Depression appears to interfere more with effortful processes than with automatic processes. This study aimed to examine attentional resources allocation by means of RT on effortful detection tasks. Ten depressed inpatients during illness and at recovery and ten healthy control subjects were given simple and choice reaction time tasks. Two types of effort demanding conditions were assessed (1) the combination of two concurrent tasks and (2) tasks involving decision making. Depressed patients improved from single to dual tasks whereas recovered and control worsened. Depressed patients showed a significant time and accuracy impairment when decision processes were involved. The decision making impairment co-occurred with a deficit in the orientation of the attention. The decline with decision making was not worsened when the choice task combined with a concurrent task and was reversible with recovery. This pattern of results exhibits differential sensitivity between two effortful tasks. Depressives may be able to mobilize resources to complete effortful tasks as far as decision processing is not required.