Koch Giacomo, Costa Alberto, Brusa Livia, Peppe Antonella, Gatto Ilaria, Torriero Sara, Gerfo Emanuele Lo, Salerno Silvia, Oliveri Massimiliano, Carlesimo Giovanni Augusto, Caltagirone Carlo
Laboratorio di Neurologia Clinica e Comportamentale, Fondazione Santa Lucia IRCCS, Via Ardeatina, 306, 00179 Rome, Italy.
Neuropsychologia. 2008 Apr;46(5):1305-13. doi: 10.1016/j.neuropsychologia.2007.12.005. Epub 2007 Dec 15.
The basal ganglia have been associated with temporal processing in ranges of milliseconds and seconds. However, results from PD patient studies are elusive. Time perception in these patients has been tested with different approaches including repetitive movement tasks (i.e. finger tapping) and cognitive tasks (i.e. time reproduction), and both abnormal and normal performances have been reported for different time intervals. Furthermore, when PD patients were required to learn two target durations in the same session when they were off medication, they overestimated the short duration and underestimated the long duration in the seconds range. This pattern of temporal accuracy was described as a "migration effect" and was interpreted as a dysfunctional representation of memory for time (Malapani, C., Rakitin, B. C., Levy, R., Meck, W. H., Deweer, B., Dubois, B., et al. (1998). Coupled temporal memories in Parkinson's disease: A dopamine-related dysfunction. Journal of Cognitive Neuroscience, 10, 316-331). Here, we controlled the emergence of similar behaviour also during millisecond time processing in PD patients. A time reproduction task was employed in which subjects were required to estimate intervals in millisecond (500ms) and few second (2000ms) ranges. In the first experiment, these intervals were tested in the same session to verify whether the migration effect was present also between time intervals in different millisecond and few second ranges. In a second experiment, they were not intermingled but were tested in two separate sessions to verify whether abnormalities depended on a selective perceptual deficit of the time intervals tested (i.e. millisecond or second ranges). All experiments were performed in both off and on therapy conditions. Our results demonstrated that PD patients showed no deficits in time estimation for time intervals in either the millisecond or few second range when the different time intervals were tested in separate sessions. This negative finding was obtained in both on and off conditions. However, when the different ranges were tested in the same session, we found that PD patients were impaired selectively for time intervals in the seconds range. Our data seem to indicate that time processing in PD patients for time intervals spanning up to 2s is unimpaired and that abnormalities in such temporal scale may emerge only when patients have to deal with different durations, when timing involves further cognitive processes such as memory and attention.
基底神经节与毫秒和秒范围内的时间处理有关。然而，帕金森病（PD）患者研究的结果并不明确。这些患者的时间感知已经通过不同方法进行了测试，包括重复性运动任务（如手指敲击）和认知任务（如时间再现），并且对于不同的时间间隔，既有异常表现也有正常表现的报道。此外，当PD患者在未服药状态下被要求在同一时段学习两个目标时长时，他们在秒级范围内高估了短时长并低估了长时长。这种时间准确性模式被描述为“迁移效应”，并被解释为时间记忆的功能失调表现（马拉帕尼，C.，拉基廷，B. C.，利维，R.，梅克，W. H.，德韦尔，B.，杜波依斯，B.等。（1998年）。帕金森病中的耦合时间记忆：一种与多巴胺相关的功能障碍。《认知神经科学杂志》，10，316 - 331）。在此，我们也控制了PD患者在毫秒级时间处理过程中类似行为的出现。采用了一项时间再现任务，要求受试者估计毫秒（500毫秒）和几秒（2000毫秒）范围内的时间间隔。在第一个实验中，这些时间间隔在同一时段进行测试，以验证在不同的毫秒和几秒范围内的时间间隔之间是否也存在迁移效应。在第二个实验中，它们没有混合，而是在两个单独的时段进行测试，以验证异常是否取决于所测试的时间间隔（即毫秒或秒范围）的选择性感知缺陷。所有实验均在未治疗和治疗状态下进行。我们的结果表明，当不同的时间间隔在单独的时段进行测试时，PD患者在毫秒或几秒范围内的时间间隔估计中没有缺陷。在治疗和未治疗状态下均得到了这一阴性结果。然而，当在同一时段测试不同范围时，我们发现PD患者在秒级范围内的时间间隔上存在选择性受损。我们的数据似乎表明，PD患者对长达2秒的时间间隔的时间处理没有受损，并且只有当患者必须处理不同时长，且计时涉及记忆和注意力等进一步认知过程时，这种时间尺度上的异常才可能出现。
