皮質応答の選択性は,シナプスの数の強さから派生する
Benjamin Scholl1,2, Connon I Thomas3, Melissa A Ryan3
1Functional Architecture and Development of Cerebral Cortex, Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA. scholl.ben@gmail.com.
Nature
|December 17, 2020
まとめ
神経皮質の選択性は 強力なシナプスの数ではなく 活性化されたシナプスの総数によって左右されます 弱いシナプスは 強いものではなく 空間的なクラスタリングを示し 伝統的なヘッビアの可塑性理論に挑戦します
科学分野:
- 神経科学
- 計算神経科学
- シナプスの可塑性
背景:
- 単一の新皮質の神経細胞は 刺激的なインプットを受け取り 感覚処理に不可欠です
- アクティビティ依存のヘブビアンの可塑性は,シナプス成熟の推定メカニズムである.
- 以前の研究では 強いシナプスが ニューロンの選択性を支配していると示唆されていました
研究 の 目的:
- フェレット視野皮質のニューロン選択性におけるシナプス強さの役割を調査する.
- 強いシナプスが ニューロンの選択性の 主な原動力であるという 予測を検証するためです
- 皮質回路におけるシナプス強さの分布と機能を調査する.
主な方法:
- In vivo 2フォトンのシナプス画像とポストホック電子顕微鏡を組み合わせた.
- 個々のシナプスを再構築し,その強さを定量化します.
- 単一のピラミッドニューロンへの刺激インプットの機能的特徴.
主要な成果:
- 強いシナプスが 主にニューロンの選択性を駆動する証拠は見つかりませんでした.
- ニューロンの選択性は,活性化されたシナプスの総数と相関しているようです.
- 空間的なクラスタリングは 強いシナプスではなく 弱いシナプスで観察されました
結論:
- この研究は,皮質神経の選択性を形成するヘッビアンメカニズムの支配的な役割に挑戦しています.
- ニューロンの選択性は,様々なシナプス強さの大きなニューロンの集団の共同活性化から生じる可能性があります.
- 弱いシナプスは空間的なクラスタリングを通して体反応に貢献する.
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