Fig 1.

Responses to head rotation before, during and after 1 week of prosthetic stimulation using a multichannel vestibular prosthesis. Column 1: Head rotational velocity (black) and mean eye rotational velocity components (horizontal, left-anterior/right-posterior [LARP], and right-anterior/left-posterior [RALP]) of a normal chinchilla during 2 Hz, 50°/s peak whole-body rotations in darkness. Top, middle and bottom rows show data during whole-body rotations about the horizontal, LARP, and RALP axes, respectively, adapted from Della Santina et al., 2007. Column 2: Head and eye velocity measured four weeks after electrode implantation and bilateral gentamicin treatment in a chinchilla, with the prosthesis set to fire at constant rates (mean 60 pulse/s on each channel) that are not modulated by head rotation. Columns 3–5: Head and eye velocity measured on the 1^st, 3^rd, and 7^th day of continuous motion-modulated prosthetic stimulation. Note the progressive (though still incomplete) reduction in wrong-axis eye movement components. Each trace is the mean of ≥5 cycles; SD <5°/s at each time point for each trace. The first half-cycle in each plot is the response to excitation of the left labyrinth.