Research press release


Nature Communications

Neuroscience: Bird neurons respond to vocal coach song



caudomedial nidopallium(NCM)は、幼鳥の歌の学習に関係すると考えられている脳領域だが、今回、沖縄科学技術大学院大学の杉山(矢崎) 陽子(すぎやま(やざき)・ようこ)の研究チームは、20羽の雄のキンカチョウの幼鳥が歌を学習する前と歌を学習している際のNCMにおける神経活動と同齢のキンカチョウ(対照群)のNCMにおける神経活動を記録した。これらのキンカチョウには9種類の歌の刺激を与えて、NCMにおける神経応答を測定した。これらの歌の刺激には、同種の別の個体の歌や別の種の個体の歌が含まれていた。9種類の音刺激のうち、チューターの歌を聴いた後にわずかな数のニューロンの活動の上昇(いわゆる「発火」)が認められたが、その他の8種類の音刺激に対してはそのような応答が認められなかった。また、この研究チームは、9種類の歌の刺激を受けた後に歌の刺激に対する神経応答が全般的に増強し、この神経応答が神経回路(GABA作動性回路)と睡眠に依存していることも明らかにした。


Specific neurons in the brains of juvenile zebra finches selectively respond to the song of an adult bird known as the tutor (usually the father), but not to the song of other adult birds. These results, described in a paper published in Nature Communications, provide insight into the neural mechanisms underlying formation of song-related memories and early learning in birds.

It is known that juvenile zebra finches learn to sing by memorizing and precisely imitating the song of an adult tutor. This process requires that a specific memory of a given tutor’s song be formed. However, direct evidence for neural activity patterns related to this memorized song has been lacking.

Yoko Yazaki-Sugiyama recorded neuronal activity in the caudomedial nidopallium (NCM) - a brain region implicated in song learning in juvenile birds - in 20 male juvenile zebra finches before and during song learning, as well as in control birds of the same species and age. They presented the birds with nine different song stimuli, including from individuals of the same species and from different species, and measured the neuronal responses in the NCM. The authors found that a small number of neurons increased their activity (so-called ‘firing’) only when following exposure to the tutors’ song and not in response to any of the other eight sound stimuli. In addition, they showed that, overall, neuronal responses to song stimuli increased after exposure to the nine song stimuli, and that this response was dependent on neuronal circuitry (GABAergic circuits) and sleep.

Further research will help determine how these song-selective neurons interact with other brain areas to guide bird song learning during development. Studying the birdsong system may also lead to novel insights into human language acquisition.

doi: 10.1038/ncomms11946

「Nature 関連誌注目のハイライト」は、ネイチャー広報部門が報道関係者向けに作成したリリースを翻訳したものです。より正確かつ詳細な情報が必要な場合には、必ず原著論文をご覧ください。

メールマガジンリストの「Nature 関連誌今週のハイライト」にチェックをいれていただきますと、毎週最新のNature 関連誌のハイライトを皆様にお届けいたします。