Vocal learning is constrained by the statistics of sensorimotor experience.
Vocal learning is constrained by the statistics of sensorimotor experience.
复制标题
声音学习受到感觉运动经验统计的限制。
DOI：
10.1073/pnas.1213622109
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发表时间：
2012
影响因子：
11.1
通讯作者：
Brainard,MichaelS
中科院分区：
文献类型：
--
作者：
Sober,SamuelJ;Brainard,MichaelS
大脑利用感觉反馈来纠正行为错误。根据定义，较大的误差需要更大的校正，并且许多学习模型假设较大的感觉反馈误差会驱动较大的运动变化。然而，另一种观点认为，较大的错误会降低学习的效率，因为此类错误超出了通常经历的错误范围，因此不太可能反映准确的反馈。这对于声音控制尤其重要，因为听觉反馈可能会受到环境噪音或感觉处理错误的污染。因此，成功的控制策略必须依靠反馈来纠正错误，同时忽略可能导致不适应的声音纠正的异常听觉信号。我们假设这些约束导致的补偿对于较小的施加误差来说是最大的，对于较大的误差来说是最小的。为了验证这一假设，我们操纵了孟加拉雀唱歌时听觉反馈的音调。我们发现，由较大的感觉误差驱动的学习速度比由较小的误差驱动的学习速度要慢，而且对所施加的误差的补偿也不太完全。此外，我们发现一个简单的原理可以解释这些数据：补偿量与音调产生的基线分布和轮班期间经历的分布之间的重叠部分成正比。相应地，当音高移出歌曲的基线音高分布时，补偿的比例接近于零。我们的数据表明，当感觉错误落入生产变异性范围内时，感觉错误可以最好地促进学习，这表明学习受到感觉运动经验统计数据的限制。
The brain uses sensory feedback to correct behavioral errors. Larger errors by definition require greater corrections, and many models of learning assume that larger sensory feedback errors drive larger motor changes. However, an alternative perspective is that larger errors drive learning less effectively because such errors fall outside the range of errors normally experienced and are therefore unlikely to reflect accurate feedback. This is especially crucial in vocal control because auditory feedback can be contaminated by environmental noise or sensory processing errors. A successful control strategy must therefore rely on feedback to correct errors while disregarding aberrant auditory signals that would lead to maladaptive vocal corrections. We hypothesized that these constraints result in compensation that is greatest for smaller imposed errors and least for larger errors. To test this hypothesis, we manipulated the pitch of auditory feedback in singing Bengalese finches. We found that learning driven by larger sensory errors was both slower than that resulting from smaller errors and showed less complete compensation for the imposed error. Additionally, we found that a simple principle could account for these data: the amount of compensation was proportional to the overlap between the baseline distribution of pitch production and the distribution experienced during the shift. Correspondingly, the fraction of compensation approached zero when pitch was shifted outside of the song’s baseline pitch distribution. Our data demonstrate that sensory errors drive learning best when they fall within the range of production variability, suggesting that learning is constrained by the statistics of sensorimotor experience.