Kansas State University, Manhattan, KS 66503, United States.
University at Buffalo, Buffalo, NY 14203, United States.
Neurosci Lett. 2020 Mar 16;721:134781. doi: 10.1016/j.neulet.2020.134781. Epub 2020 Jan 28.
Auditory detection can improve with practice. These improvements are often assumed to arise from selective attention processes, but longer-term plasticity as a result of training may also play a role. Here, listeners were trained to detect either an 861-Hz or 1058-Hz tone (counterbalanced across participants) presented in noise at SNRs varying from -10 to -24 dB. On the following day, they were tasked with detecting 861-Hz and 1058-Hz tones at an SNR of -21 dB. In between blocks of this active task, EEG was recorded during passive presentation of trained and untrained frequency tones in quiet. Detection accuracy and confidence ratings were higher for trials at listeners' trained, than untrained-frequency (i.e., learning occurred). During passive exposure to sounds, the P2 component of the auditory evoked potential (∼150 - 200 ms post tone onset) was larger in amplitude for the trained compared to the untrained frequency. An analysis of global field power similarly yielded a stronger response for trained tones in the P2 time window. These effects were obtained during passive exposure, suggesting that training induced improvements in detection are not solely related to changes in selective attention. Rather, there may be an important role for changes in the long-term neural representations of sounds.
听觉检测可以通过练习得到提高。这些改进通常被认为是选择性注意过程的结果，但训练引起的长期可塑性也可能发挥作用。在这里，听众被训练在噪声中检测到 861Hz 或 1058Hz 的音调（在参与者之间平衡），SNR 从-10 到-24dB。在第二天，他们的任务是在 SNR 为-21dB 的情况下检测 861Hz 和 1058Hz 的音调。在这个主动任务的块之间，在安静环境中被动呈现训练和未训练频率音调时记录 EEG。对于在听众的训练频率上的试验，检测准确性和置信度评分高于未训练频率（即，发生了学习）。在被动暴露于声音期间，听觉诱发电位（约在音调开始后 150-200ms）的 P2 成分的幅度对于训练频率比未训练频率更大。全局场功率的分析同样在 P2 时间窗口中产生了对训练音调更强的反应。这些效应是在被动暴露期间获得的，这表明训练引起的检测改进不仅仅与选择性注意的变化有关。相反，声音的长期神经表示的变化可能起着重要作用。
