Sakata Jon T, Brainard Michael S
Keck Center for Integrative Neuroscience, Department of Physiology, University of California, San Francisco, San Francisco, California 94143-0444, USA.
J Neurosci. 2006 Sep 20;26(38):9619-28. doi: 10.1523/JNEUROSCI.2027-06.2006.
Songbirds and humans both rely critically on hearing for learning and maintaining accurate vocalizations. Evidence strongly indicates that auditory feedback contributes in real time to human speech, but similar contributions of feedback to birdsong remain unclear. Here, we assessed real-time influences of auditory feedback on Bengalese finch song using a computerized system to detect targeted syllables as they were being sung and to disrupt feedback transiently at short and precisely controlled latencies. Altered feedback elicited changes within tens of milliseconds to both syllable sequencing and timing in ongoing song. These vocal disruptions were larger when feedback was altered at segments of song with variable sequence transitions than at stereotyped sequences. As in humans, these effects depended on the feedback delay relative to ongoing song, with the most disruptive delays approximating the average syllable duration. These results extend the parallels between speech and birdsong with respect to a moment-by-moment reliance on auditory feedback. Moreover, they demonstrate that song premotor circuitry is sensitive to auditory feedback during singing and suggest that feedback may contribute in real time to the control and calibration of song.
鸣禽和人类都严重依赖听觉来学习和维持准确的发声。有力的证据表明,听觉反馈对人类言语有实时贡献,但反馈对鸟鸣的类似贡献仍不清楚。在这里,我们使用一个计算机系统来评估听觉反馈对 Bengalese 雀歌声的实时影响,该系统在鸟鸣被唱出时检测目标音节,并在短且精确控制的延迟下短暂干扰反馈。改变的反馈在几十毫秒内就引发了正在进行的歌声中音节序列和时间的变化。当在具有可变序列转换的歌曲片段处改变反馈时,这些发声干扰比在刻板序列处更大。与人类一样,这些影响取决于相对于正在进行的歌声的反馈延迟,最具干扰性的延迟接近平均音节持续时间。这些结果扩展了言语和鸟鸣在对听觉反馈的即时依赖方面的相似性。此外,它们表明歌曲运动前区回路在歌唱过程中对听觉反馈敏感,并表明反馈可能对歌声的控制和校准有实时贡献。