FIG. 2.

Spatial tuning curves elicited by individual and simultaneous monopolar stimulation of two scala tympani electrodes. The left ordinate axis plots recording depth in the ICC relative to the most superficial recording site; corresponding CFs are plotted on the right ordinate. The abscissa plots the current level of single electrical pulses. (A) and (C) Responses to monopolar stimulation of scala tympani electrodes 3 and 8, respectively, stimulated individually in monopolar configuration. Electrode 8 was centered in the scala tympani 3.75 mm more apical than electrode 3. (B) Activity elicited by simultaneous stimulation of the two electrodes. Stimulus currents on the two electrodes were varied in parallel; upper and lower rows of abscissa labels refer to currents presented to the electrodes represented in panels (A) and (C), respectively. The current ranges used in the simultaneous condition (indicated with black bars in panels (A) and (C)) were entirely below the thresholds for activation with either electrode alone. FSDR is defined in the text. Cat0509.