• Top page
  • Timetable
  • Per session
  • Per presentation
  • How to
  • Meeting Planner




開催日 2014/9/13
時間 14:00 - 15:00
会場 Poster / Exhibition(Event Hall B)

Gravitational effect on three-dimensional directional sensitivity in wind-evoked response of ascending projection neurons

  • P3-172
  • 谷村 佳奈子 / Kanako Tanimura:1 小川 宏人 / Hiroto Ogawa:2 
  • 1:北海道大院・生命・生命システム / Biosystem Sci, Grad Sch Life Sci, Hokkaido Univ, Hokkaido, Japan 2:北海道大院・理・生物科学 / Dept Bio Sci, Fac Sci, Hokkaido Univ, Hokkaido, Japan 

Animals achieve spatial perception of enviorment according to spatial information of remotely-received stimuli, such as light and sound. Resolution and dynamic range of the sensory system are biased along the antero-posterior and dorso-ventral axes, which will be related to directions of gravitational force and locomotion. However, there are few studies about gravitational and locomotion effects on the sensory bias of specific sensory system. In this study, we used cricket cercal system, which detects air current surrounding animal in all directions. The receptor organs for this system, called cerci were covered with 750-1000 mechanoreceptive hairs innervated by sensory neuron. Sensory information about stimulus direction is processed by local circuit within terminal abdominal ganglion (TAG) and conveyed to thoracic and cephalic ganglia by ascending projection interneurons, part of which has been identified as giant interneurons (GIs). Previous works have described distinct directional selectivity in the horizontal plane of GIs and other interneurons, but the directionality along the vertical axis is unknown. We developed three-dimensional air-current stimulator and performed multi-unit recording of ascending spikes to analyze their sensitivity to all directions. Three-dimensional directional tuning based on all evoked spikes showed highest sensitivity to ipsi-lateral angle to the recorded side in the horizontal plane. On the other hand, there was little bias in the longitudinal and vertical planes. The sensitivity along the antero-posterior axis was higher than that along the dorso-ventral axis. Individual units sorted from the extracellular recording indicated various response properties including directional selectivity, preferred angle, and shape of the tuning curve. In addition, when the attitudinal change from prone posture to upright in which antero-posterior axis corresponded to with the gravity direction modulated the 3-D directional sensitivity. The fact that ablation of clavate hairs that are gravity and acceleration sensors on the cerci eliminated this modulation suggests multisensory integration between gravity and air-current sensory systems within TAG.

Copyright © Neuroscience2014. All Right Reserved.