Ludwig-Maximilians-Universität, Department of Neurology, D-81377 Munich, Germany.
Behav Brain Res. 2011 Jun 20;220(1):74-82. doi: 10.1016/j.bbr.2011.01.027. Epub 2011 Jan 22.
Sequence learning has been the subject of research in various paradigms but has not been investigated for learning deferred imitation of long spatial sequences. In this task no guiding stimuli support the sequence reproduction and all sequence information has to be recalled from memory. We investigate this kind of imitation learning with a task in which a long sequence of spatial positions has to be reproduced without guiding stimuli, either by manual pointing or by ocular fixations. Sequences consisting of 20 positions were acquired after only 25 training trials. The persistence of learned sequences over several days showed that the sequence was retained in long-term memory. A transfer test revealed that the learned sequence was independent of the effector. A detailed analysis of the error distributions of pointing and ocular fixations was performed to characterize the guiding control signal. The independence of the variable position errors from the movement directions as well as the lack of error propagation between successive targets suggest that the reproduction in this learning task was guided by sequential positions rather than sequential displacements.
序列学习一直是各种范式的研究课题，但尚未针对长空间序列的延迟模仿学习进行研究。在这个任务中，没有指导刺激来支持序列再现，所有的序列信息都必须从记忆中回忆起来。我们通过一项任务来研究这种模仿学习，在这项任务中，必须在没有指导刺激的情况下通过手动指向或眼动注视来再现长的空间位置序列。在仅 25 次训练试验后，就可以获得由 20 个位置组成的序列。经过几天的学习，序列仍然存在，这表明序列被保存在长期记忆中。转移测试表明，所学习的序列与效应器无关。我们对指向和眼动注视的误差分布进行了详细分析，以描述指导控制信号。位置误差与运动方向无关，并且连续目标之间没有误差传播，这表明在这个学习任务中，再现是由序列位置而不是序列位移引导的。
