This multiplexing of motor-related information in a sensory neuron’s response could not be evidenced

in earlier experiments where behavior and electrophysiology were carried out separately (Fotowat and Gabbiani, 2007) or when animals were restrained to a trackball (Santer et al., 2008). Although our results strongly suggest multiplexing, they do not definitively prove it. This will require specific manipulation of the DCMD activity during ongoing behavior. Multiplexing of sensory information across populations of neurons has been documented earlier, particularly in the vertebrate visual and olfactory system, but its relation to behavior remains to be determined (Meister, 1996 and Friedrich et al., 2004; for a review see Panzeri et al., 2010). In invertebrates, several examples of neurons that contribute to distinct, and sometimes mutually exclusive, motor see more behaviors have been studied as well. These neurons can be thought of as being multiplexed, but on a very different time scale as that evidenced here (Kristan and Shaw, 1997). Our finding that distinct aspects of a complex, time-dependent motor behavior can be Epigenetics inhibitor encoded by distinct attributes of the time-varying

firing rate of a single sensory neuron suggests that similar encoding may occur at the sensory-motor interface in other systems, including vertebrates. We designed and built a custom integrated circuit that performs the amplification, analog to digital conversion, multiplexing, and wireless transmission of four low-noise channels: two for neural and two for muscle recordings (Figure S1). not The neural and muscle recordings are amplified with gains of 1000 and 100, respectively,

and filtered in the range of 300 Hz–5.2 kHz and 20 Hz–280 Hz, respectively. A 9 bit analog-to-digital converter samples them at 11.52 kHz and 1.92 kHz, respectively. The digital wireless transmitter operates based on a frequency-shift keying scheme at 920 MHz. The size of the packaged chip is 5 × 5 mm2 and was mounted on a 13 × 9 mm2 printed circuit board (PCB). Data from an accelerometer mounted on the PCB were also transmitted (ADXL330, Analog Devices, Norwood, MA; sampling rate: 1.92 kHz, bandwidth: 0–500 Hz). The accelerometer provided high temporal resolution but saturated for accelerations above ∼3.8 gn (gn = 9.8 m/s2). Therefore, we estimated the peak acceleration based on the video recordings. For this purpose, we tracked the position of the locust eye frame-by-frame and computed numerically its second derivative around the time of the peak. Wireless telemetry ran for 2 hr on a pair of 1.5 V batteries (#337, Energizer, St. Louis, MO). The weight of the system including batteries was 0.79 g (1.2 g after connecting and fixing the transmitter to the animal).