Fig. 4. Motor neuronal activity recorded from the three motor nerve branches (proximal-, middle- and distal-flexor nerves) supplying the main flexor muscle before, during and after thanatosis. The maintenance phase of thanatosis is shaded grey. During thanatosis, activity of intermediate- and fast-exciters was almost completely suppressed (A–E). The intermediate exciters tended to be activated more frequently when ventilatory movements (deflections, lower trace) occurred frequently during thanatosis (B). However, their activity was not necessarily coupled with ventilation phases but seen also in non-ventilatory phases (arrows and time-stretched inset in B). In other recordings, intermediate units vigorously activated with ventilatory movements during the quiescent state (C) were rather suppressed when ventilatory movements occurred during thanatosis (D). Fast exciter units are truncated in A, B and E. Note that voluntary leg movements immediately after arousal occurred in B but not in A and E.