Ejaculation related events elicited by electrical microstimulation of LSt neurons. (a) Simultaneous recording of Δp(SV) (red) and BSM-EMG (black) elicited by LSt neuron microstimulation in an anesthetized rat. Green traces indicate stimulation period, grey traces indicate background activity. The overlay (right) displays the sequential activation of SV and BSM after microstimulation. Inset, middle: evoked BSM-EMG on an expanded timescale; note the rhythmic bursting pattern. (b) Averaged response for 7 animals [protocol and color codes as in (a)]. BSM-EMG is shown rectified and 200 Hz low-pass filtered. Vertical blue lines: onset of BSM-EMG activity and time when 95% of BSM-EMG activity has occurred. (c) Simultaneous recording of Δp(VD) (red) and BSM-EMG (black) elicited by LSt neuron microstimulation [stimulation protocol (green) as in (a)]. Top: example experiment. Bottom: averaged response from 5 animals (BSM-EMG rectified and low-pass filtered). Grey traces: background activity. The negative phase after the Δp(VD) peak reflects VD refilling with perfusion solution.