Pre- and Post-test thresholds for each training stimulus, stimulus class and testing mode.

<p><b>(A)</b> Pre-test (empty symbols) and post-test (full symbols) thresholds on the speech discrimination task for each phoneme minimal-pair stimulus. Thresholds are plotted as the phoneme number (on the continuum between 1 and 96), tested on the blocked condition (top panels) and random mode (bottom panels). Five training groups (shown from left to right on the x-axis of each panel) were tested on each mode: Blocked (B) and Random (R) Speech, Blocked (B) and Random (R) Duration, and untrained Controls (C). Note that the top and bottom panels denote different training groups (10 groups in total; see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0118465#sec002" target="_blank">Methods</a> for details). All error bars denote 95% confidence intervals. <b>(B)</b> Pre- and post-test thresholds on the duration discrimination task for each reference stimulus duration, plotted as per-cent of the reference duration. Top panels show performance on the blocked tests, while the bottom panels show performance on the random test for the same groups as (A).