Lampen Jennifer, Jones Katherine, McAuley J Devin, Chang Soo-Eun, Wade Juli
Neuroscience Program, Michigan State University, East Lansing, Michigan, United States of America.
Department of Psychology, Michigan State University, East Lansing, Michigan, United States of America.
PLoS One. 2014 Sep 26;9(9):e108841. doi: 10.1371/journal.pone.0108841. eCollection 2014.
Rhythm is important in the production of motor sequences such as speech and song. Deficits in rhythm processing have been implicated in human disorders that affect speech and language processing, including stuttering, autism, and dyslexia. Songbirds provide a tractable model for studying the neural underpinnings of rhythm processing due to parallels with humans in neural structures and vocal learning patterns. In this study, adult zebra finches were exposed to naturally rhythmic conspecific song or arrhythmic song. Immunohistochemistry for the immediate early gene ZENK was used to detect neural activation in response to these two types of stimuli. ZENK was increased in response to arrhythmic song in the auditory association cortex homologs, caudomedial nidopallium (NCM) and caudomedial mesopallium (CMM), and the avian amygdala, nucleus taeniae (Tn). CMM also had greater ZENK labeling in females than males. The increased neural activity in NCM and CMM during perception of arrhythmic stimuli parallels increased activity in the human auditory cortex following exposure to unexpected, or perturbed, auditory stimuli. These auditory areas may be detecting errors in arrhythmic song when comparing it to a stored template of how conspecific song is expected to sound. CMM may also be important for females in evaluating songs of potential mates. In the context of other research in songbirds, we suggest that the increased activity in Tn may be related to the value of song for assessing mate choice and bonding or it may be related to perception of arrhythmic song as aversive.
节奏在诸如言语和歌曲等运动序列的产生中很重要。节奏处理缺陷与影响言语和语言处理的人类疾病有关，包括口吃、自闭症和诵读困难。鸣禽由于在神经结构和发声学习模式上与人类相似，为研究节奏处理的神经基础提供了一个易于处理的模型。在这项研究中，成年斑胸草雀接触自然有节奏的同种鸟鸣或无节奏的鸟鸣。使用对即刻早期基因ZENK的免疫组织化学来检测对这两种类型刺激的神经激活。在听觉联合皮层同源物、尾内侧巢核（NCM）和尾内侧中脑皮层（CMM）以及鸟类杏仁核、带状核（Tn）中，ZENK对无节奏鸟鸣的反应增加。CMM在雌性中的ZENK标记也比雄性更多。在感知无节奏刺激期间，NCM和CMM中神经活动的增加与人类听觉皮层在接触意外或受干扰的听觉刺激后活动的增加相似。当将无节奏鸟鸣与存储的同种鸟鸣预期声音模板进行比较时，这些听觉区域可能在检测无节奏鸟鸣中的错误。CMM对雌性评估潜在配偶的歌声也可能很重要。结合鸣禽的其他研究，我们认为Tn中活动的增加可能与歌声在评估配偶选择和配对中的价值有关，或者它可能与将无节奏鸟鸣视为厌恶刺激的感知有关。
