The mean response latency for correct button press responses was about 115 ms slower in patients compared to controls for both tones (M ±SD, controls vs. patients; 422.8 ±116.5 vs. 541.6 ±123.8 ms) and syllables (448.7 ±117.6 vs. 557.6 ±138.1 ms; group main effect, F[1,44] = 11.1, p = .002), and across groups about 20 ms faster for tones than syllables (task main effect, F[1,44] = 5.55, p = .02), which is in accordance with our previous findings.10,33,48 Performance accuracy was high for both groups, and likely subject to ceiling effects, although the mean hit rate was marginally lower for patients compared to controls (95.9 ±7.1 vs. 98.2 ±5.2%; group main effect, F[1,44] = 2.97 p = .09). However, there was no task difference in performance accuracy (tonal vs. phonetic, 97.1 ±6.8 vs. 97.0 ±6.0%), nor were there any interactions with group. There were also no significant behavioral effects involving response hand.
