Neural circuit mechanisms for controlling voluntary behavior in crayfish

DOI Web Site 2 Citations 51 References
  • KAGAYA Katsushi
    Hokkaido University Department of Biological Sciences, Faculty of Science

Bibliographic Information

Other Title
  • ザリガニに見る自発性行動制御の神経回路機構
  • ザリガニ ニ ミル ジハツ セイコウドウ セイギョ ノ シンケイ カイロ キコウ

Search this article

Abstract

  Animals initiate behavior not only reflexively in response to external stimuli but also voluntarily depending on their internal state. What are the neuronal mechanisms that subserve voluntary initiation of behavior? I have identified brain neurons involved in voluntary walking of crayfish, Procambarus clarkii. I found brain neurons whose spike activities increased>1 sec before the spontaneous behavioral onset. This activity is indicative of readiness or preparatory activities in the vertebrate brain that precede the onset of voluntary actions. Therefore, I termed this activity as ‘readiness discharge’. Readiness discharge neurons were found to be silent when walking was initiated by external stimuli, but other neurons were specifically activated for the stimulus-evoked walking. Readiness discharge was not associated with any specific direction of walking. Other walking direction-specific neurons were activated after the readiness discharge units were activated, suggesting hierarchical control for the spontaneous initiation of walking from its general aspects to more specifics. Furthermore, I found brain neurons whose activities increased during walking and others that were activated at the termination of walking. Thus, it was revealed that voluntary walking is controlled by descending interneurons that are organized for behavioral initiation, continuation and termination in a hierarchical way. Further intracellular studies revealed that readiness discharge are shaped by sequential excitatory and inhibitory synaptic inputs rather than by endogenous excitability changes. The synaptic activation is most likely to take place in the medial protocerebrum in the crayfish brain. I propose that recurrent neural circuits subserve the activation.

Journal

Citations (2)*help

See more

References(51)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top