人類大腦左側的特定區(qū)域控制說話和語言處理,，而一項研究在鳴禽的腦中發(fā)現(xiàn)了類似組織,，其常常被研究，從而理解人類如何學習說話,。與人類類似,，鳴禽通過模仿它們的照顧提供者從而在嬰兒期學習發(fā)音。
刊登在PNAS的一篇報告中,，Sanne Moorman及其同事比較了接觸了父親的鳴叫或者接觸不熟悉的鳴叫的年輕的和成年的斑胸草雀的神經(jīng)活動模式,。這組作者發(fā)現(xiàn)了兩個區(qū)域的左側激發(fā)。一個區(qū)域稱為HVC,，它被認為類似于人類大腦管理語言產(chǎn)生的所謂布羅卡區(qū),；稱為NCM的第二個區(qū)域被認為類似于管理語言處理的韋尼克區(qū)。
HVC的左側激發(fā)出現(xiàn)在年輕和成年的斑胸草雀中,，而不論這種動物接觸的鳴叫如何,，而NCM區(qū)域的激發(fā)僅僅發(fā)生在接觸父親的鳴叫的幼鳥中。這些結果向這組作者提示，幼鳥的NCM區(qū)的左側激發(fā)是與記憶有關的,，而且對鳴叫學習具有特異性,。這組作者說，這些發(fā)現(xiàn)提示類似的神經(jīng)機制參與了鳥鳴學習和人類語言的獲得,。（生物谷Bioon.com）
doi:10.1073/pnas.1207207109
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Human-like brain hemispheric dominance in birdsong learning
Sanne Moormana,1, Sharon M. H. Gobesa,b,c, Maaike Kuijpersa, Amber Kerkhofsa, Matthijs A. Zandbergena, and Johan J. Bolhuisa
Unlike nonhuman primates, songbirds learn to vocalize very much like human infants acquire spoken language. In humans, Broca’s area in the frontal lobe and Wernicke’s area in the temporal lobe are crucially involved in speech production and perception, respectively. Songbirds have analogous brain regions that show a similar neural dissociation between vocal production and auditory perception and memory. In both humans and songbirds, there is evidence for lateralization of neural responsiveness in these brain regions. Human infants already show left-sided dominance in their brain activation when exposed to speech. Moreover, a memory-specific left-sided dominance in Wernicke’s area for speech perception has been demonstrated in 2.5-mo-old babies. It is possible that auditory-vocal learning is associated with hemispheric dominance and that this association arose in songbirds and humans through convergent evolution. Therefore, we investigated whether there is similar song memory-related lateralization in the songbird brain. We exposed male zebra finches to tutor or unfamiliar song. We found left-sided dominance of neuronal activation in a Broca-like brain region (HVC, a letter-based name) of juvenile and adult zebra finch males, independent of the song stimulus presented. In addition, juvenile males showed left-sided dominance for tutor song but not for unfamiliar song in a Wernicke-like brain region (the caudomedial nidopallium). Thus, left-sided dominance in the caudomedial nidopallium was specific for the song-learning phase and was memory-related. These findings demonstrate a remarkable neural parallel between birdsong and human spoken language, and they have important consequences for our understanding of the evolution of auditory-vocal learning and its neural mechanisms.
