The Neuronal Control of Flying Prey Interception in Dragonflies
Final rept. 15 May 2010-14 May 2014
UNION COLL SCHENECTADY NY
Pagination or Media Count:
Eight pairs of large descending visual neurons TSDNs control dragonfly prey interception flights. We investigated both the sensory inputs and the motor outputs of this group of neurons. A detailed map was obtained of the position and direction of target movement that excites each of the TSDNs. This study also revealed the anatomy of the TSDN output terminals, providing information about the likely pattern of connectivity from individual TSDNs to the neural circuitry controlling each of the wings. Angular speed is also encoded by the TSDNs. This speed sensitivity increases the gain of the system as the dragonfly approaches its prey. Distance appears not to be encoded by the TSDNs when the head is fixed. However binocular inputs are required for maximal responses. The functional implication of the binocular inputs is not yet known. Intracellular electrical stimulation of individual TSDNs confirmed their role in adjusting wing position and angle. TSDN activity rotates the head as well in the direction opposite the preferred target direction. Two TSDNs also move the legs and mouthparts.
- Anatomy and Physiology
- Target Direction, Range and Position Finding