Williams David, Kühn Andrea, Kupsch Andreas, Tijssen Marina, van Bruggen Gerard, Speelman Hans, Hotton Gary, Yarrow Kielan, Brown Peter
Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, Queen Square, London WCIN 3BG, UK.
Brain. 2003 Sep;126(Pt 9):1975-85. doi: 10.1093/brain/awg194. Epub 2003 Jul 7.
The speed with which one reacts to an imperative signal depends on the extent to which preceding cues predict that command. When reliable warning cues are available, the processing of the imperative stimulus can be favoured and responses partially pre-prepared, leading to shorter reaction times. Here we seek evidence for involvement of the human basal ganglia in the exploitation of behaviourally relevant predictive cues. To this end, local field potentials (LFPs) were recorded in the region of the subthalamic nuclei of parkinsonian patients during the performance of a pre-cued reaction task in which the cue either predicted or failed to predict the demands of the imperative signal. We demonstrate that LFP activity in the beta frequency band ( approximately 20 Hz) is modulated by the behavioural relevance of the external cue. The findings suggest that, first, the subthalamic nucleus is involved in mediating or facilitating the response advantage derived from predictive cues in humans and, secondly, variations in synchronous neuronal activity in the beta band may contribute to this function in the subthalamic nucleus.
个体对命令信号的反应速度取决于先前线索对该命令的预测程度。当有可靠的预警线索时，命令刺激的处理会得到促进，反应也会部分提前准备好，从而导致反应时间缩短。在这里，我们寻找证据证明人类基底神经节参与了对行为相关预测线索的利用。为此，在帕金森病患者丘脑底核区域记录了局部场电位（LFP），这些患者在执行一个有线索提示的反应任务，其中线索要么预测了命令信号的要求，要么未能预测。我们证明，β频段（约20Hz）的LFP活动受到外部线索行为相关性的调节。研究结果表明，首先，丘脑底核参与介导或促进人类从预测线索中获得的反应优势，其次，β频段同步神经元活动的变化可能有助于丘脑底核的这一功能。
