Normative Planning Linked to Risk for Suicidal Behavior in Non-Psychotic Unipolar Depression

Patients with depression who have attempted suicide have worse response inhibition but better normative planning performance than patients with depression who have not previously attempted suicide, according to findings published in Europe’s Journal of Psychology.

The researchers compared 20 patients with non-psychotic unipolar depression who had attempted suicide with 20 matched patients who had not attempted suicide and with 20 healthy control participants. All participants who had attempted suicide in the past had a mean of 3 suicidal acts.

To assess the neuropsychological profile of the participants, the researchers used the Go/No-Go Task, Tower of London Task, Iowa Gambling Task, Victoria Stroop Test, Wisconsin Card Sorting Test, Finger Tapping Task, Trail Making Test, Verbal Fluency Test, and Auditory Verbal Learning Test. These tests measured executive functioning, attention, verbal memory, processing speed, and psychomotor speed, respectively.

Participants with depression who had previously attempted suicide performed worse in the Go/No-Go Task, which assesses response inhibition, compared with participants who had not attempted suicide and the control group. No difference was found between participants who had not attempted suicide and controls.

Participants with depression who had not attempted suicide performed worse in the Tower of London task, a visuospatial planning task, compared with participants who had attempted suicide and controls. No difference was found between participants who had attempted suicide and controls.

Healthy controls outperformed all participants with depression regardless of history of suicide attempts, including the Iowa Gambling Task, Victoria Stroop Test, Wisconsin Card Sorting Task, Finger Tapping Task, and Trail Making Test.

Regarding the results of the Tower of London task, the researchers wrote, “As in previous studies, we expected poor performances in both depressive groups, and this normative performance in planning might contribute to the risk of suicide because it enables organization of each step in pursuit of a certain objective or intention, such as a suicidal act.”

Reference

Moniz M, Neves de Jesus S, Pacheco A, et al. The influence of planning and response inhibition on cognitive functioning of non-psychotic unipolar depressed suicide attempts. Eur J Psychol. 2017;13(4):717-732