通信に対するネットワークの振動反応には阻害フィードバックが必要ですが,獲物の刺激にはなりません
Brent Doiron1, Maurice J Chacron, Leonard Maler
1Physics Department, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada. bdoiron@science.uottawa.ca
Nature
|January 31, 2003
まとめ
電気魚の感覚神経は,振動状態と非振動状態を切り替えることができる. これにより,通信信号と捕獲物の検出を阻害フィードバックを使用して区別することができます.
科学分野:
- 神経科学は神経科学である.
- 計算神経科学とは
- センサリーシステム センサリーシステム
背景:
- 刺激によって引き起こされる神経振動は,感覚システム全体で観察されます.
- 阻害的接続は振動を生成することが知られている.
- 感覚処理における時空感覚入力と振動動的ダイナミクスの役割は不明である.
研究 の 目的:
- 弱い電気性の魚の感覚ピラミッドニューロンが,異なる刺激タイプにどのように反応するかを調査する.
- 刺激特有の振動ネットワークダイナミクスを生成する阻害フィードバックの役割を理解する.
- 感覚処理におけるこれらの振動状態の機能的意義を解明する.
主な方法:
- 弱い電気を持つ魚の感覚ピラミッドニューロンからのin vivo電気生理学的記録.
- 既知の回路に基づいたネットワークモデルの開発.
- リバーシブルブロックによるフィードバック阻害による実験操作.
主要な成果:
- 感覚ピラミッドニューロンは,コミュニケーションのような刺激に対して振動反応を示したが,獲物のような刺激には振動反応を示さなかった.
- ネットワークモデルの予測では,分散型遅延阻害フィードバックは,刺激特有の振動的行動に不可欠である.
- ブロックフィードバック阻害は,コミュニケーションのような刺激に対する振動反応を廃止しました.
結論:
- 弱い電気魚の感覚システムは,神経発火状態を切り替えるために抑制フィードバックを使用します.
- このトーグリングメカニズムは,コミュニケーションと獲物の刺激の異なる処理を可能にします.
- 振動的および非振動的状態は,異なる自然主義的な感覚入力と動的に結びついています.
関連する概念動画
00:46Feedback Inhibition
Biochemical reactions are occurring constantly in cells, converting starting substances to different products, usually with the help of enzymes that speed the reactions. Without enzymes, it would take far too long for most reactions to occur to be useful to the cell!
01:29Excitatory and Inhibitory Effects of Neurotransmitters
When an action potential reaches the presynaptic axon terminal, it releases neurotransmitters from the neuron into the synaptic cleft at a chemical synapse. The released neurotransmitter can be excitatory or inhibitory. The critical criteria commonly used to determine whether a molecule is a neurotransmitter at a chemical synapse are the molecule's presence in the presynaptic neuron. Second, its release is in response to strong presynaptic depolarization. And lastly, the presence of specific...
01:19The Role of Ion Channels in Neuronal Computation
A postsynaptic neuron usually receives numerous impulses from several other presynaptic neurons. The axon hillock of the postsynaptic neuron integrates all these signals and determines the likelihood of firing an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
01:07Cell Signaling Feedback Loops
Positive and negative feedback loops are crucial for regulating biological signaling systems. These feedback loops are processes that connect output signals to their inputs.
Negative feedback loops
Most signaling systems have negative feedback loops that can perform different functions such as output limiter, and adaptation.
Output limiter
Upon receiving an input signal, the cellular response rapidly increases until a threshold is reached. Beyond this threshold, a negative feedback loop...
Negative feedback loops
Most signaling systems have negative feedback loops that can perform different functions such as output limiter, and adaptation.
Output limiter
Upon receiving an input signal, the cellular response rapidly increases until a threshold is reached. Beyond this threshold, a negative feedback loop...
01:27Feedback Regulation of Calcium Concentration
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
01:28Neuronal Communication
Neurons, the fundamental units of the brain and nervous system, communicate through complex electrochemical signals that underpin all cognitive and bodily functions. This communication is primarily facilitated by a process involving the generation and propagation of an action potential along the axon of the neuron. When the internal electrical charge of a neuron surpasses a certain threshold, an action potential is triggered. This rapid change in voltage travels swiftly along the axon to the...