皮質の方向選択性は,タラミックシナプスの収束時に現れる
Anthony D Lien1,2,3, Massimo Scanziani4,5,6,7
1Neurosciences Graduate Program, University of California San Diego, La Jolla, CA, USA. anthony.d.lien@gmail.com.
Nature
|May 26, 2018
まとめ
視覚野の神経細胞は,正確なタイミングでタラミックの神経細胞からのインプットを統合することによって,運動方向の選択性を達成します. この時空の統合は,基本的な視覚処理のタスクであるオブジェクトの運動方向の検出を可能にします.
科学分野:
- 神経科学
- 計算神経科学
- 視覚処理
背景:
- 方向選択性は哺乳類の視覚皮質の視覚処理に不可欠です
- 皮質ニューロンは,特定の時空の遅延で入力を統合することによって,方向選択性を達成すると考えられています.
- この時空の偏移の正確な細胞メカニズムと起源は不明です
研究 の 目的:
- ネズミの視覚皮質の神経細胞における方向選択性へのタラミックインプットの寄与を調査する.
- 運動方向の計算におけるタラミックインプットの空間時間的統合の役割を明らかにする.
主な方法:
- ネズミの視覚皮質に発射する約80~100個のタラミックニューロンの活動を記録する.
- ネズミの視覚皮質を刺激して ニューロンの反応を観察します
- 異なる場所での刺激に対するタラミックニューロンの時間的な反応の特徴を分析する.
主要な成果:
- タラミックニューロンは 異なる空間的な場所での刺激に対して 異なる時間的反応プロファイルを示した.
- これらのタラミックニューロンは 視覚刺激中に視覚皮質ニューロンを刺激します
- これらのタラミック入力と適切な時空偏移の統合は,皮質ニューロンの方向選択性へのバイアスを授与した.
結論:
- タラミックニューロンは 視覚皮質に空間的・時間的に多様なインプットを 提供します
- 皮質ニューロンは,方向選択性を達成するために,タラミックインプットの空間時間的多様性を活用します.
- このメカニズムは 神経回路から 動きの方向性のような 基本的な視覚的特徴が 抽出される方法を示しています
関連する概念動画
The Synapse
133.7K
Neurons communicate with one another by passing on their electrical signals to other neurons. A synapse is the location where two neurons meet to exchange signals. At the synapse, the neuron that sends the signal is called the presynaptic cell, while the neuron that receives the message is called the postsynaptic cell. Note that most neurons can be both presynaptic and postsynaptic, as they both transmit and receive information.
133.7K
Convergent Evolution
33.1K
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.
33.1K
Emerging Adulthood
718
Jeffrey Arnett's concept of emerging adulthood offers a framework to understand the unique developmental stage between adolescence and full-fledged adulthood, generally from ages 18 to 25. This period is marked by extensive exploration and shifts in identity, relationships, and career choices, a process known in psychology as role experimentation. Emerging adulthood reflects the evolving cultural expectations surrounding adulthood and the dynamic process of personal transformation during...
718
Region of Convergence
960
The z-transform is a powerful mathematical tool used in the analysis of discrete-time signals and systems. It is a crucial tool in the analysis of discrete-time systems, but its convergence is limited to specific values of the complex variable z. This range of values, known as the Region of Convergence (ROC), is fundamental in determining the behavior and stability of a system or signal. The ROC defines the region in the complex plane where the z-transform converges, which can take various...
960
Convergence of Fourier Series
427
The Fourier series is a powerful mathematical tool for representing periodic signals as an infinite sum of complex exponentials. In practice, this infinite series is truncated to a finite number of terms, yielding a partial sum. This truncation makes the approximation of the signal feasible but introduces certain challenges, particularly near discontinuities, known as the Gibbs phenomenon.
The Gibbs phenomenon refers to the persistent oscillations and overshoots that occur near discontinuities...
The Gibbs phenomenon refers to the persistent oscillations and overshoots that occur near discontinuities...
427
Electrical Synapses
10.9K
Electrical synapses found in all nervous systems play important and unique roles. In these synapses, the presynaptic and postsynaptic membranes are very close together (3.5 nm) and are actually physically connected by channel proteins forming gap junctions.
Gap junctions allow the current to pass directly from one cell to the next. In contrast, in the chemical synapse, the neurotransmitters carry the information through the synaptic cleft from one neuron to the next. They consist of two...
Gap junctions allow the current to pass directly from one cell to the next. In contrast, in the chemical synapse, the neurotransmitters carry the information through the synaptic cleft from one neuron to the next. They consist of two...
10.9K


