大脳皮質の領野間連合回路の形成機構

Development of Inter-areal Association Projections in the Cerebral Cortex

大脳皮質の同側の機能領野間を直接結ぶ神経回路（連合回路）はヒトを含む霊長類で特に発達しており，高度な認知機能を担っていると考えられている。また，発達障がいなどの疾患とこの回路の異常の関連も指摘されている。本論では，回路形成初期における連合回路の軸索の伸長過程の解析結果を中心に，発生・発達期における連合回路の形成機構についての現在の知見と今後の展望をまとめる。

Abstract

Direct projections between functional areas within the ipsilateral hemisphere (association projections) play a key role in higher cognitive functions. Deficits in these circuits are correlated with various pathological conditions including developmental disorders. We investigated the development of association projections in the mouse neocortex using single-neuron resolution imaging and observed that these were formed as interstitial collaterals that originate as buds from callosal projections of the same neurons. In this review, we describe our findings with regard to the development of association projections, together with mechanisms underlying these processes and also future perspectives in the field.