Adolescent neurons exhibit variable responses to perceptual training. A, Multiunit (circles) and single-unit (triangles) thresholds from the first day of perceptual training are plotted against thresholds from the second day of perceptual training. Only units that were successfully monitored across multiple consecutive training days were included in this and all subsequent panels in this figure. Data points falling above the line of unity (dashed line) are units that improved from day 1 to day 2; data points falling below this line are units that worsened. The number of units (animals) contributing to this dataset are as follows: adolescent, 33 (4); adult, 16 (2). B–D, Same as A, but for comparisons of day 1 with day 3 [B; adolescent, 27 (4); adult, 16 (2)], day 4 [C; adolescent, 19 (2); adult, 14 (2)], and day 5 [D; adolescent, 14 (2); adult, 12 (2)]. The panels depicting adult data in this figure were originally published in the study by Caras and Sanes (2017). *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. n.s., not significant.