Temporal specificity of perceptual learning in an auditory discrimination task
Temporal specificity of perceptual learning in an auditory discrimination task
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DOI：
10.1101/lm.55503
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发表时间：
2003-03-01
影响因子：
2
通讯作者：
Buonomano, DV
中科院分区：
文献类型：
--
作者：
Karmarkar, UR;Buonomano, DV
虽然时间处理被广泛应用于各种感觉和运动任务中，但很少有证据表明，在几十到几百毫秒的时间范围内，是一个单一的中央时钟还是一个分布式系统。我们通过研究听觉间隔辨别任务的学习是否在刺激类型、间隔和频率上具有普遍性来调查这个问题。时序的改善在多大程度上延续到不同的刺激特征，限制了时序的神经机制。在100或200毫秒的间隔辨别任务中训练的人类受试者在时间分辨率上有所提高。这种学习推广到感知上不同的持续时间刺激，以及以未训练的频谱频率呈现的音调的训练间隔。性能的提高（不能推广到未经训练的时间间隔）。为了确定谱泛化是否依赖于任务中频率信息的重要性，受试者同时在频率识别的两个不同间隔上进行训练。总的来说，我们的结果表明，大脑使用专用于特定时间跨度的回路，并且每个回路处理跨非时间刺激特征的刺激。泛化模式还表明，时间学习不依赖于早期皮层下加工的变化，因为非时间特征在早期阶段由不同的通道编码。
Although temporal processing is used in a wide range of sensory and motor tasks, there is little evidence is to whether a single centralized clock or a distributed system underlies timing in the range of tens to hundreds of milliseconds. We investigated this question by studying whether learning on an auditory interval discrimination task generalizes across stimulus types, intervals, and frequencies. The degree to which improvements in timing carry over to different stimulus features constrains the neural mechanisms underlying timing. Human subjects trained on a 100- or 200-msec interval discrimination task showed an improvement in temporal resolution. This learning generalized to a perceptually distinct duration stimulus, as well as to the trained interval presented with tones at untrained spectral frequencies. The improvement in performance (lid not generalize to untrained intervals. To determine if spectral generalization was dependent on the importance of frequency information in the task, subjects were simultaneously trained on two different intervals identified by frequency. As a whole, our results indicate that the brain uses circuits that are dedicated to specific time spans, and that each circuit processes stimuli across nontemporal stimulus features. The patterns of generalization additionally indicate that temporal learning does not rely on changes in early, subcortical processing, because the nontemporal features are encoded by different channels at early stages.