programmable stimulator model 3800 multistim  (A-M Systems)

Journal: The Journal of Experimental Biology

Article Title: Flight power muscles have a coordinated, causal role in controlling hawkmoth pitch turns

doi: 10.1242/jeb.246840

Figure Lengend Snippet: Electrical stimulation allows controlled change of DLM timing, leading to changes in body pitch torque. (A) Diagram of stimulation experiment signal flow. Analog spike detection is run on a DVM signal post-amplification, enabling a microcontroller to trigger a stimulator with specific timings relative to observed DVM spikes (see , for a similar experiment). (B) Voltage recordings, aligned at the time of the stimulus, from all four power muscles in a quiescent moth while stimulation is applied, illustrating the efficacy of electrical stimulation. Lighter dotted traces are 0.03 mA current of stimulation, darker solid traces are 0.05 mA current. (C) Example trace of EMG and vertical force ( F z ) and pitching torque data (τ x ) during stimulation. Stimulation was applied at time t =0 (denoted by vertical line with lightning symbol) and produced a phase advance in right and left DLM (RDLM and LDLM) spikes. Alternating shaded regions indicate wingstrokes found via negative-to-positive zero crossings of the Hilbert transform of F z (light gray dashed line). (D) Phase of all spikes in stimulation wingstroke plotted against the phase at which stimulation was applied for that wingstroke on the x -axis. Red points indicate right muscle, blue points indicate left muscle. If stimulation is inducing spikes in the DLM, then spikes along an identity line should be observed only in the DLM (right) column. Note that mean natural DLM phase of this dataset is at 32.7% of the wingstroke.

Article Snippet: The controller would trigger a stimulator (A-M Systems Model 3800) with a stimulus isolation unit (A-M Systems Model 2200) on a controlled delay time from the onset of a detected DVM spike.

Techniques: Amplification, Muscles, Produced