IMPAIRMENT OF VISUALLY GUIDED ASSOCIATIVE LEARNING IN PATIENTS WITH BORDERLINE PERSONALITY DISORDER
Beside the affective symptoms, Borderline personality disorder (BPD) could alter several cognitive functions, too, which are connected to different brain regions, mainly to the basal ganglia, the frontal lobe and the hippocampi.The Rutgers acquired equivalence learning test was developed in order to investigate the contribution of the basal ganglia and the hippocampi to associative learning functions. First part of the test is the acquired equivalence learning based on feedback, which will be followed by the test phase where the earlier learnt (retrieval) and new predictable associations (generalization) will be asked without any given feedback to the subjects. The acquisition phase is primarily connected to the basal ganglia, while the test phase is mainly to the hippocampi. We analyzed the number of acquisition trials (NAT), the acquisition learning error ratio (ALER), the retrieval error ratio (RER) and the generalization error ratio (GER) of 24 BPD patients. In BPD patient group the NAT and ALER were significantly (p<0.05) higher than those of the matched healthy controls. On the other hand, the RER and GER were not impaired in BPD patients. The reaction times of BPD patients and the controls were not different in any parts of the test. Based on our results BPD patients could build associations with lower effectiveness, which suggest the impairment of cognitive functions connected to the basal ganglia. On the other hand, the retrieval and generalization parts of the test phase, which depends primarily on the function of the hippocampus are not affected negatively by BPD.