Information processing and cognitive organization in unipolar depression: Specificity and comorbidity issues

This study investigated information processing and cognitive organization i n clinical depression. The specificity of various cognitive mechanisms to d epression was also examined. Twenty-six depressed/ anxious individuals, 24 pure depressives, 25 never-depressed anxious controls, and 25 nonpsychiatri c controls completed a modified Stroop task, the Self-Referent Encoding Tas k, and two tasks designed to assess cognitive structure. Comorbid depressed /anxious, depressed, and anxious groups per-formed similarly to one another but differed significantly from nonpsychiatric controls, on the processing and organization of negative content. Specificity to depression was also o btained, as both depressed groups endorsed and recalled less positive infor mation and organized positive self-relevant information with less interconn ectedness than anxious individuals and nonpsychiatric controls. These resul ts suggest that depressed individuals have an interconnected negative self- representational system and lack a well-organized positive template of self . These findings are discussed in terms of cognitive models of depression a nd the tripartite model of depression and anxiety.