Meeting Abstract
The mechanosensory lateral line in fishes detects movement, vibration, and pressure gradients in water. However, the effect of self-generated movement on the sensitivity of the lateral line remains largely unknown. Microwire electrodes were inserted into the anterior lateral line nerve of toadfish using an implantable micromanipulator which allowed neural activity to be monitored for up to two weeks post-implant. Experiments measured neural response to external stimulus during forward movement. Freely swimming fish remained sensitive to stimuli produced by a vibrating sphere indicating that the lateral line can detect external stimuli during movement. Additionally, moving fish were able to detect the stimuli generated by the tail motions of a robotic fish. There was no evidence of efferent modulation during forward movement and efferent nerves did not show increased firing during swimming. While efferent modulation or central filtering of self-generated movements had previously been postulated as mechanisms to allow free swimming fish to continue to detect outside stimuli, the current experiments show that at the swim speeds observed, the mechanosensory lateral line can sense external stimuli without modulation or filtering.
