Executive functioning in depressed patients with suicidal ideation

Objective: Suicidal thinking has been associated with cognitive rigidity, however, not all depressed patients contemplate suicide. Therefore, we hypothesized that compared with depressed subjects without suicidal ideation, depressed individuals with suicidal ideation would display poorer performance on measures of executive functioning that involve mental flexibility. Method: In-patients with a current major depressive episode who had no current suicidal ideation (n = 28) were compared with those who had current suicidal ideation (n = 25) on measures of executive functioning and two neurocognitive tests that predominantly assess non-frontal regions. Results: Compared with non-suicidal depressed patients, depressed suicidal patients performed significantly worse on several measures of executive functioning after controlling for age, IQ, severity of depression and prior suicide attempts. The two groups performed similarly on tests that predominantly assess non-frontal regions. Conclusion: Depressed individuals contemplating suicide have cognitive rigidity, which does not appear to be a global brain dysfunction. Suicidal mental states may result from dysfunctional executive decision-making that is associated with the frontal lobe.