| Description: |
Existing research presents a working understanding of Borderline Personality Disorder (BPD) patients’ symptomatology, traits, and behavior in everyday life, but how they combine and utilize prior and likelihood (current sensory) information when making decisions remains unclear. Bayesian Decision Theory suggests that optimal decision-making behavior should combine and weigh both pieces of information according to their relative uncertainties, such that people rely more on the information with less uncertainty when making a decision. Though this optimal behavior has been observed in neuro-typical populations, prior literature suggests that certain neuro-atypical populations can deviate. Some characteristics of BPD patients, such as impulsive behavior and drastic changes in the overall perception of themselves and others, suggest that they may be over-relying on likelihood information and not sufficiently taking prior information into account. From a Bayesian perspective, this can be interpreted as having ‘weak’ priors which may lead to suboptimal decision-making. Here, we investigated this hypothesis by having BPD patients (n = 23) and healthy controls (n = 18) perform a coin-catching sensorimotor task with varying levels of prior and likelihood information uncertainty. Our results indicate that, contrary to our prediction, BPD patients were able to use prior information, and that their use of prior and likelihood information follows qualitatively Bayesian behavior. We found that BPD patients, at least in a lower-level and non-affective sensorimotor task, are still able to use both prior and likelihood information and react appropriately to the respective uncertainties. This could be suggesting that any potential deficits in the use of prior information may not be widespread or only be apparent in affectively-charged interpersonal contexts. |