Borderline personality disorder, but not euthymic bipolar I disorder, is associated with prolonged post-error slowing in sensorimotor performance

- Individuals with borderline personality disorder (BPD) and bipolar disorder (BD) both present with heightened impulsivity and poor behavioural controls.
- Little is known about sensorimotor control in BPD and BD and whether they differ in their ability to balance their speed and accuracy of performance and restore performance following mistakes.
- We find that BPD and BD is associated were unchanged response times and accuracy in a simple binary-choice reaction time task (without attentional or response conflicts).
- However, BPD is associated with selectively and dramatically prolonged post-error slowing before resuming normative levels of speed and accuracy.
- BPD and BD individuals can in fact achieve normative speed-accuracy trade-offs; but slowed recovery following errors may distinguish BPD from BD in sensorimotor control.

BackgroundBorderline personality disorder (BPD) and bipolar disorder (BD) are common psychiatric diagnoses. Impulsivity and affective instability are prominent features of both illnesses, complicate treatment and are associated with poor clinical outcomes. Yet, little is known about sensorimotor control in these populations, whether they differ in their speed and accuracy of performance, and their ability to restore efficient performance following errors.MethodsTwenty females with DSM-IV BPD, 20 females with DSM-IV BD and 20 age- and cognitive-ability matched healthy control participants completed a simple, brief reaction time task in which two single-attribute stimuli were mapped to distinct motor responses.ResultsInspection of response latencies and errors showed that both the BPD and BD participants were able to respond as quickly and accurately as controls, reducing reaction times gently prior to errors, but that BPD participants showed prolonged post-error slowing (PES) before resuming normative levels of speed and accuracy.LimitationsBD and BPD participants were taking psychotropic medication.ConclusionsThese findings suggest that BPD and BD individuals can achieve normative speed-accuracy trade-offs; but that only BPD individuals exhibit differentially slowed recovery following errors, indicating a specific impartment in basic sensorimotor control.