サル下側頭葉皮質の水平軸索終末集団の空間配置

谷川 久、藤田一郎

1997 日本神経科学大会

下側頭葉皮質TE野における内在性水平軸索の結合様式を調べる目的で、2種の順行性トレーサーをTE野内の隣接部位に注入した。各トレーサーで標識される軸索終末集団は、多くの場合、空間的に分離していた。このことは、隣接部位を発した水平軸索は出力先では隣り合わずに、それぞれ別部位からの出力先と隣り合っていることを意味する。隣接部位間で密な軸索連絡が存在することから、上記結合様式は、TE野の多様な図形特徴選択性コラムの間での相互作用を可能にすると考えられる。


TOPOGRAPHY OF INTRINSIC HORIZONTAL CONNECTIONS IN THE MACAQUE INFERIOR TEMPORAL AREA TE: A DOUBLE LABELING STUDY.

The topographic organization of intrinsic horizontal connections was analyzed in the inferior temporal area TE of the Japanese macaque.  Paired injections of two anterograde tracers, PHA-L and BDA, were administered into adjacent sites in the upper layers of the TE.  The center-to-center distance between the paired injections was 0.5-1 mm, so that the two injection sites abutted each other.  Each injection produced 5-15 patches of labeled horizontal axons within the TE.  Although one or two of the patches received projections from both injection sites, most of the patches produced by the two injections neither overlapped nor adjoined each other.  The results indicate that the two abutting sites in the TE are largely connected to separated sets of cortical sites within the TE.  Given the extensive fiber connections between adjacent cortical sites, we suggest that the organization revealed here increase the opportunity for interaction among columns which are selective for different object features.


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