Intact action segmentation in Parkinson's disease: Hypothesis testing using a novel computational approach
Intact action segmentation in Parkinson's disease: Hypothesis testing using a novel computational approach
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帕金森病的完整动作分割：使用新颖的计算方法进行假设检验
DOI：
10.1016/j.neuropsychologia.2015.09.034
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发表时间：
2015
期刊：
影响因子：
2.6
通讯作者：
Schönberger
中科院分区：
文献类型：
--
作者：
Schiffer;Nevado-Holgado;Johnen;Schönberger
众所周知，行动观察会触发对正在进行的行动过程的预测，因此被认为是预测感知的标志性例子。一个相关的任务是动作分割，它明确地利用了根据动作的内部表示来预测动作的能力。该任务要求参与者划分一个行动步骤完成和另一个行动步骤开始的位置。因此，它受益于对当前行为的时间精确预测。这些外部事件时间预测的形成和利用现在与包括基底神经节和前额叶皮层在内的网络密切相关。由于多巴胺能神经支配的衰退导致帕金森病（PD）中基底神经节和前额叶皮层的功能受损，我们假设帕金森病患者在动作分割任务中表现出增加的时间变异性，特别是在停药时（假设1）。动作分割的另一个重要方面是其依赖于动作的语义表示。没有证据表明，非痴呆帕金森病患者的动作表征发生了实质性改变，或者无法被获取。因此，我们预计 PD 患者和健康对照的动作分割判断遵循相同的总体模式（假设 2），从而产生可比较的分割概况。这两种假设都用一种新的分类方法进行了测试。我们在本研究中为这两种假设提供了证据：当测试分类器预测帕金森病患者分割的电影的身份的能力时，分类器的性能略有下降，而当患者在没有获得序列记忆的情况下在停药时分割电影时，反应行为的规范性指标会下降。这种结果模式与假设 1 一致。然而，分类器分析还显示，患者和对照组给出的反应产生了非常相似的特定动作模式，从而提供了支持假设 2 的证据。就方法论而言，本研究中分类器的使用使我们能够建立跨组行为的相似性（假设 2）。该方法开辟了标准统计方法通常无法提供的新途径，并根据其优点进行了讨论，以衡量研究人群之间假设的相似性。
Action observation is known to trigger predictions of the ongoing course of action and thus considered a hallmark example for predictive perception. A related task, which explicitly taps into the ability to predict actions based on their internal representations, is action segmentation; the task requires participants to demarcate where one action step is completed and another one begins. It thus benefits from a temporally precise prediction of the current action. Formation and exploitation of these temporal predictions of external events is now closely associated with a network including the basal ganglia and prefrontal cortex.Because decline of dopaminergic innervation leads to impaired function of the basal ganglia and prefrontal cortex in Parkinson's disease (PD), we hypothesised that PD patients would show increased temporal variability in the action segmentation task, especially under medication withdrawal (hypothesis 1).Another crucial aspect of action segmentation is its reliance on a semantic representation of actions. There is no evidence to suggest that action representations are substantially altered, or cannot be accessed, in non-demented PD patients. We therefore expected action segmentation judgments to follow the same overall patterns in PD patients and healthy controls (hypothesis 2), resulting in comparable segmentation profiles. Both hypotheses were tested with a novel classification approach.We present evidence for both hypotheses in the present study: classifier performance was slightly decreased when it was tested for its ability to predict the identity of movies segmented by PD patients, and a measure of normativity of response behaviour was decreased when patients segmented movies under medication-withdrawal without access to an episodic memory of the sequence. This pattern of results is consistent with hypothesis 1. However, the classifier analysis also revealed that responses given by patients and controls create very similar action-specific patterns, thus delivering evidence in favour hypothesis 2.In terms of methodology, the use of classifiers in the present study allowed us to establish similarity of behaviour across groups (hypothesis 2). The approach opens up a new avenue that standard statistical methods often fail to provide and is discussed in terms of its merits to measure hypothesised similarities across study populations.
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影响因子：
14.5
作者：
Dagher, A;Owen, AM;Brooks, DJ
通讯作者：
Brooks, DJ
影响因子：
14.5
作者：
FLOWERS, K
通讯作者：
FLOWERS, K
影响因子：
11
作者：
CRAWFORD, T;GOODRICH, S;KENNARD, C
通讯作者：
KENNARD, C
评估帕金森病患者预先确定的脚本事件序列存在缺陷
影响因子：
3.6
作者：
T. Zalla;A. Sirigu;B. Pillon;B. Dubois;J. Grafman;Y. Agid
通讯作者：
Y. Agid
日常行动和计划的认知神经心理学
影响因子：
3.4
作者：
M. Schwartz
通讯作者：
M. Schwartz