Plastic Change in the Auditory Minimum Threshold Induced by Intercollicular Effects in Mice

Figure 4

RAFs of the four pairs of IC neurons obtained before (unfilled circles) and after 30 min (filled circles) focal electric stimulation of each IC neuron. (a) The responses of both neurons (a)(A) and (a)(B) were reciprocally inhibited during the focal electrical stimulation of each IC neuron (ES b and ES a) and resulted in lowered RAFs (filled versus unfilled). (b) By contrast, reciprocal focal electric stimulation only lowered the RAF of neuron (b)(A) but not the RAF and MT of the other neuron (b)(B). (c) The responses of both neurons (c)(A) and (c)(B) were reciprocally facilitated during the focal electrical stimulation of each neuron (ES b ES a). This occurrence elevated the RAF (filled versus unfilled). (d) Reciprocal focal electric stimulation only elevated the RAF of one neuron (d)(A) but not the other neuron (d)(B). The respective BF (kHz), MT (dB SPL), and recording depth (μm) of these eight IC neurons were 11.6, 52, and 969 for (a)(A) and 12.4, 56, and 1230 for (a)(B); 14.1, 50, and 1063 for (b)(A) and 8.4, 58, and 1509 for (b)(B); 9.8, 57, and 859 for (c)(A) and 11.7, 58, and 794 for (c)(B); and 9.8, 60, and 1321 for (d)(A) and 9.7, 69, and 1274 for (d)(B).

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