Tactile spatial acuity from childhood into adulthood.

Data from the current study (filled circles) are plotted together with those from Peters et al. [11] (open circles). (A) and (B) show simple linear regressions. (A) threshold vs. age. (B) threshold vs. fingertip surface area. (C) and (D) show results of a multiple regression with both age and surface area as independent variables. (C) surface area-adjusted threshold vs. age. (D) age-adjusted threshold vs. surface area. In (C) and (D), thresholds were respectively adjusted to the mean surface area and mean age of the aggregate participant sample. Black solid curves in all panels: least-squared exponential fits. In (A) and (C), for plotting purposes only, we have omitted the data from the oldest participant, a 27.29 year-old from [11] (threshold 1.22 mm, area-adjusted threshold, 1.30 mm).