Neuropsychological Study On Time Perception In Patients With Parkinson's Disease

Objective The aim of this study was to explore the abilities of Parkinson's disease (PD) patients in skills of time estimation from the perspective of cognitive neuropsychology, and to test the hypothesis that basal ganglia is involved in the special network of time perception.Method Thirty-two individuals with idiopathic Parkinson's disease were compared to Thirty-two matched healthy controls using time reproduction task. Time reproduction was required for three time intervals of 0.6 second, 3 and 5 seconds with visual pictures. Individuals need to reproduce those time intervals after 1-second or 5-second delaying. Computer recorded the results of reproduction automatically.Result Compared with healthy controls, at the 3-second duration reproduction task, PD patients in the case of delay in 1s (2.78±0.31s and 2.15±0.34s, respectively) and the delay in the case of 5s (2.74±0.32s and 2.08±0.37s, respectively) showed significant reduction on the ability of time reproduction (t=-7.459,-7.533, p<0.01), and they underestimate the interval; at the 5-second duration reproduction task, PD patients group in the delay of 1s the next(3.99±0.39s and 3.11±0.52s) and the delay in the case of 5s (4.05±0.40s and 2.96±0.54s)the ability of time reproduction is also significantly impaired compared with the healthy controls(t=-7.609,-9.12, p<0.01), and they underestimate the interval as well; but in 600-millisecond time reproduction task, PD patients group 1s in the case of delay (0.91±0.18s and 0.90±0.18s, respectively)and the delay in the case of 5s (0.89±0.16s and 0.91±0.17s, respectively)time replication capabilities and the control group a considerable difference was not statistically significant(t=0.347,p=0.730; t=-0.519,p = 0.606, respectively).Conclusion Our data indicates that time processing in PD patients is impaired, and we also found that PD patients were impaired selectively for time intervals in the seconds range when timing involves further cognitive processes such as memory and attention.