Visualization of ensemble activity patterns of mechanosensory afferents in the cricket cercal sensory system with calcium imaging.

摘要: The cercal sensory system of the cricket mediates detection and analysis low velocity air currents in animal's immediate environment, is implemented around an internal representation current direction that demonstrates essential features a continuous neural map. Previous neurophysiological anatomical studies have yielded predictions global spatio-temporal patterns activity should be evoked afferent map by stimuli different directions. We tested those direct visualization ensemble using Ca2+ -sensitive indicators. AM ester fluorescent indicator (Oregon Green 488 BAPTA-1 AM) was injected under sheath nerve containing all mechanosensory axons from one cercus. Optical signals were recorded with digital intensified CCD camera. Control experiments electrical stimulation stained unstained nerves demonstrated observed within terminal abdominal ganglion (TAG) due to activation dye-loaded neurons. To visualize spatial air-current-evoked activity, unidirectional applied repeatedly eight directions, optically responses each averaged. dispersion optical limited resolution which these could observed. However, adequate demonstrate directional induced elevation arbors afferents TAG. These coarsely- resolved, optically-recorded consistent anatomy-based predictions.