Representative examples of the neural response (AN2 neuron from a <i>T. leo</i>) after adaptation to noise stimuli of duration 75 ms (dotted line), 600 ms (dashed line), and 4800 ms (solid line).

<p>(A–D) Responses (spike rates) during a test stimulus of 1 s duration (cf. protocol of <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1000182#pcbi-1000182-g003" target="_blank">Figure 3A</a>). Relative intensities of the test stimuli range from −3 dB (A) to +6 dB (D); the average relative intensity of the adapting stimulus was 0 dB. Each stimulus was presented 5 times and the recorded spike trains (1 ms resolution) were convolved with a Gaussian kernel (σ = 50 ms). The instantaneous spike rates were estimated by averaging over the 5 repetitions. The increase of the estimated rate during the first 50 ms is an artifact introduced by filtering the neural response with the Gaussian kernel. Note that the onset latency of the AN2 neuron is in the range of 15 to 18 ms. The spike counts during the sample period (shaded) from 100 ms to 300 ms are used to construct neural response curves.