Neuronal control of the forewings in two different behaviours: Stridulation and flight in the cricket, Teleogryllus commodus

Abstract

The forewing of the cricket is activated during the performance of two different behaviours, flight and stridulation. Intracellular recording and staining techniques were employed to determine the neuronal basis for these two behaviours and how they are interrelated. Both motor patterns were studied in a deafferented preparation. Stridulation was elicited by electrical stimulation of the brain and flight by brief puffs onto the cerci. 1. Bifunctional mesothoracic motoneurons (MN 90, MN 99) are activated with different patterns of synaptic input during flight and stridulation (Fig. 2). 2. Metathoracic flight motoneurons (MN 112, MN 119, MN 129) are only activated during flight and do not receive phasic excitatory input during stridulation (Figs. 3 and 6). 3. Two separate interneuronal pools, which include interneurons with resetter properties, appear to exist, one activated during flight, the other one activated during stridulation (Figs. 4 and 5). The interactions between these two pools are inhibitory. Both motor patterns may be switched rapidly (less than 0.5 s; Fig. 6). 4. It is possible to elicit both behaviours at the same time and then no strict coupling is observed between them (Figs. 7 to 9).