Function of basal ganglia-cortical circuits in vocal learning in early life

基底神经节-皮质回路在早期声音学习中的功能

• 批准号: 8445192
• 负责人: Satoshi Kojima
• 金额: $ 7.83万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8445192
• 关键词: Acoustics; Address; Adolescent; Adult; Anterior; Aversive Stimulus; Basal Ganglia; Behavior; Behavior Control; Birds; Cell Nucleus; Complex; Data; Development; Functional disorder; Human; Infant; Learning; Left; Life; Measures; Modeling; Motor; Motor Skills; Movement Disorders; Negative Reinforcements; Neurophysiology - biologic function; Operant Conditioning; Output; Parents; Parkinson Disease; Pathway interactions; Performance; Play; Process; Production; Prosencephalon; Psychological reinforcement; Reporting; Research; Role; Songbirds; Source; Speech; Structure; Study models; Testing; Training; Variant; Work; age related; bird song; critical period; insight; juvenile animal; neuromechanism; relating to nervous system; response; sequence learning; vocal learning; vocalization

DESCRIPTION (provided by applicant): Young songbirds learn to produce complex vocalizations (song) from their adult tutor during a critical period of development, just as human infants learn to speak from their parents. Since song learning critically depends on a discrete and specialized basal ganglia-thalamo-cortical circuit called the anterior forebrain pathway (AFP), songbirds offer a great and rare opportunity to study the mechanisms underlying basal ganglia-dependent learning of complex motor skills in early life. One of the major obstacles in studying song learning mechanisms is complexity of the behavior. Juvenile birds gradually develop their song from unstructured and highly variable vocalizations akin to human babbling, by changing many acoustic and temporal features all together. This highly complex learning makes it difficult to examine precise functions of neural structures and activity in behavior. Recent studies have overcome this difficulty by using much simpler learning of adult song, which is experimentally induced using an operant conditioning paradigm with aversive stimuli and is targeted to a specific feature of song (e.g., pitch of a particular portion of song). Althouh these studies have revealed important functions of the AFP in adult song learning, it is still unknown whether the same functions are employed for the much more complex, self-driven learning of juvenile song. Indeed, several recent findings, including my own preliminary data, even raise the possibility that juvenile song learning is substantially different from that of aduls in its mechanisms. Thus, examining whether the findings in adult song learning are generally applicable to juvenile song learning is critically important for understanding the mechanisms of song learning, and an answer either way will be a significant advance in the birdsong research field. This proposal specifically addresses this issue by directly comparing several aspects of AFP's function in juvenile song learning with those in adult song learning reported previously. To do so, I will use new behavioral manipulations of juvenile learning that allow us to precisely analyze the same features of juvenile song as those analyzed in adult song learning (both pitch and sequence), and thus enable us to examine the AFP's function in the same way as that in the adult learning studies. This study will not only test whether adults provide a faithful model fr studying mechanisms of juvenile song learning, but will also show that detailed analyses of song learning mechanisms can be done even in juveniles, using targeted manipulations of learning - this provides a new and powerful approach to the study of vocal learning mechanisms in songbirds. Moreover, this study has the potential to reveal differences in neural mechanisms between self-driven, age-dependent development of complex motor skills in young animals such as speech acquisition in human infants, and simple, training-induced changes of well-learned adult behavior such as fine adjustment of speech production in adults. PUBLIC HEALTH RELEVANCE: Young songbirds learn to produce complex vocalizations during a critical period of development, offering a great opportunity to study the mechanisms underlying development of complex motor skills in early life, such as speech acquisition in human infants. This proposal will investigate neural mechanisms of songbird vocal learning by focusing on the function of a cortical-basal ganglia circuit, which plays a crucial role in motor production and learning in general and is the locus of numerous movement disorders such as Parkinson's disease in humans. This study will thus provide general insight into mechanisms underlying development of complex behaviors in early life, as well as into the pathophysiology of movement disorders attributable to abnormality of cortical-basal ganglia circuits.

描述（由申请人提供）：年轻的鸣禽在发育的关键时期从他们的成人导师那里学习发出复杂的声音（歌曲），就像人类婴儿从父母那里学习说话一样。由于鸣禽的学习主要依赖于一个被称为前前脑通路（AFP）的离散和专门的基底神经节-丘脑-皮层回路，因此鸣禽提供了一个难得的机会来研究早期生活中依赖基底神经节的复杂运动技能学习的机制。研究鸣叫学习机制的主要障碍之一是鸣叫行为的复杂性。幼鸟通过改变许多声音和时间特征，逐渐从无结构和高度可变的声音发展出他们的歌曲，类似于人类的咿呀学语。这种高度复杂的学习使得研究神经结构和行为活动的精确功能变得困难。最近的研究已经克服了这一困难，通过使用更简单的成人歌曲学习，这是实验诱导使用操作性条件反射范式与厌恶刺激，并针对歌曲的特定特征（例如，歌曲的特定部分的音高）。尽管这些研究揭示了AFP在成人歌曲学习中的重要功能，但对于更为复杂的、自我驱动的青少年歌曲学习是否也具有相同的功能，我们仍然不得而知。事实上，最近的一些发现，包括我自己的初步数据，甚至提出了一种可能性，即青少年的歌曲学习在机制上与成年人有本质上的不同。因此，研究成年鸣声学习的发现是否普遍适用于幼年鸣声学习，对于理解鸣声学习的机制至关重要，任何一种答案都将是鸟类鸣声研究领域的重大进展。本研究通过直接比较AFP在青少年歌曲学习中的几个方面的功能与先前报道的成人歌曲学习中的功能，专门解决了这个问题。为了做到这一点，我将使用新的青少年学习行为操作，使我们能够准确地分析青少年歌曲的特征，就像在成人歌曲学习中分析的那样（包括音高和序列），从而使我们能够以与成人学习研究相同的方式检查AFP的功能。这项研究不仅将测试成鸟是否为研究幼鸟鸣叫学习机制提供了一个忠实的模型，而且还将表明，使用有针对性的学习操作，甚至可以在幼鸟身上进行鸣叫学习机制的详细分析——这为研究鸣禽的鸣叫学习机制提供了一种新的有力方法。此外，这项研究有可能揭示幼年动物自我驱动的、年龄依赖性的复杂运动技能发展（如人类婴儿的语言习得）与简单的、训练诱导的成熟成人行为变化（如成人语言产生的精细调节）之间的神经机制差异。