FIGURE 7.

Steady-state-adapted hdc^JK910 photoreceptor output to Mid and Bright naturalistic stimulation show less modulation but their information transfer is remarkably similar to the wild-type. (A) Mean wild-type (black) and hdc^JK910 (red) R1–R6 photoreceptors’ voltage response to a repeated 1 s long naturalistic light intensity time series pattern of different brightness. (B) In Bright and Mid, hdc^JK910 R1–R6 output had significantly less modulation than the wild-type (Bright: SD_wild-type = 6.85 ± 0.37 mV, SD_hdc = 4.13 ± 0.27 mV, p = 4.427 × 10^-5, one-tailed t-test; Mid: SD_wild-type = 5.93 ± 0.40 mV, SD_hdc = 4.92 ± 0.23 mV, p = 0.028, one-tailed t-test). In Bright, wild-type output modulation was the largest (p = 0.007, one-tailed paired t-test) while hdc^JK910 modulation reduced in respect to Mid (p = 2.980 × 10^-4, one-tailed paired t-test). In Dim, hdc^JK910 and wild-type outputs showed similar modulation (Dim: SD_wild-type = 2.16 ± 0.27 mV, SD_hdc = 2.40 ± 0.23 mV, p = 0.520, two-tailed t-test). (C) In Mid, hdc^JK910 signal had less power than the wild-type only in low frequencies (f < 6Hz, p < 0.029, one-tailed t-test). In Dim, hdc^JK910 and wild-type signal power spectra were similar. (D) In Bright, hdc^JK910 R1–R6 output had less signal power than the wild-type over a broad frequency range (f < 34Hz, p < 0.023, one-tailed t-test). (E) Noise power spectra of wild-type and hdc^JK910 photoreceptor outputs were similar to all three tested brightness levels. Data in Dim condition is not shown for clarity. (F) Signal-to-noise ratios of wild-type and hdc^JK910 photoreceptor outputs were remarkably similar over the three tested brightness levels. Data for Mid stimulation are not shown for clarity. (G) Information transfer rate estimates of wild-type and mutant photoreceptor outputs were remarkably similar (Dim: R_wild-type = 54.73 ± 3.67, R_hdc = 59.53 ± 4.23; Mid: R_wild-type = 220.44 ± 10.75, R_hdc = 252.92 ± 17.86; Bright: R_wild-type = 240.40 ± 14.62, R_hdc = 240.64 ± 17.41, all in bits/second, p > 0.05, two-tailed t-test). Wild-type photoreceptors showed higher information transfer rates in Bright stimulation than in Mid (p = 0.004, one-tailed paired t-test) while hdc^JK910 photoreceptors encoded similar information rates in Mid and Bright (p = 0.138, two-tailed paired t-test). (H) For 8–24 Hz frequency range, wild-type photoreceptor outputs to Bright naturalistic stimulation carried significantly more power than to Mid intensities (p < 0.001, paired one-tailed t-test). (I) hdc^JK910 photoreceptor outputs to Bright and Mid naturalistic stimulations had similar power spectra (p > 0.05, paired two-tailed t-test). (A–I): Mean ± SEM, n_wild-type = 7, n_hdc = 8. All recordings performed at t = 19°C.