Although previous studies have suggested that bipolar disorder symptoms could result from increased impulsivity and vulnerability of the Behavioural Activation System (BAS), the association of the Behavioural Inhibition System (BIS) with the disorder remains unclear.

Given that motivational systems, especially BAS, and impulsivity are closely intertwined, we aimed to assess the associations between BIS and BAS and impulsivity among healthy volunteers and remitted bipolar outpatients.

70 euthymic bipolar outpatients and 70 healthy controls were self assessed with the BIS/BAS Scale and the Barratt Impulsivity Scale.

Our data revealed elevated BIS and BAS sensitivity (Figure 1a) as well as impulsivity (Figure 1b) in the group of bipolar outpatients. Both motivational systems seem to be unrelated to the trait impulsivity.

Our results indicate that BIS/BAS sensitivity and impulsivity represent a distinct trait. Furthermore, elevated BIS and BAS sensitivity and impulsivity in the euthymic phase of the disorder could represent an indicator of relatively stable personal traits which persist throughout all phases of the illness, thus signifying a vulnerability factor that could be relevant in the early diagnostic picture of affective disorders.