Inhibition and response to error in remitted major depression

• Impaired Stop Signal inhibition, but normal Stroop performance, in remitted MDD.
• Intact post-error adjustment in remitted MDD.
• Varying inhibition tests is important in assessment of depression vulnerability.

Depression is a common illness which tends to have a relapsing progression. Revealing vulnerability factors is an important step towards improved treatment and prevention. Previous studies of individuals in remission indicate that inhibitory control is more strongly impaired than other cognitive functions. Studies have mostly used Stroop tasks; it is unclear how this population performs on other measures of inhibition. Abnormal reactions to errors may also promote depression relapse, but this has rarely been studied in remitted depression. We used a Stop Signal task and Stroop inhibition task to investigate inhibitory function and post-error reaction time adjustments in 54 individuals with a history of depression and 185 never-depressed controls. Inhibitory processing was slower among the remitted depressed individuals on the Stop Signal task, but no difference was found in Stroop inhibition. The groups were not different on post-error adjustments. This finding extends the understanding of inhibitory deficiency in this population and offers insight into trait markers of depression.