Figure 2.

(A) ERP traces at electrode FCz in control subjects and pre-HD subjects at the three longitudinal time points. The stimulus was presented at time 0, the time scale (x-axis) is in milliseconds (ms). Red lines indicated results for “incompatible” switch trials, green lines “compatible” switch trials, black curves “compatible” non-switch trials, and brown curves “incompatible” non-switch trials. (B) Mean N2 amplitudes at electrode FCz for pre-HD subjects and control subjects at the three time points in the incompatible switch condition. (C) Cohen's d effect sizes in the pre-HD and control groups show the effects between baseline and 15 months and between the 15-month and 21-month endpoints. (D) Mean P3 amplitudes at electrode Pz for pre-HD subjects and control subjects at the three time points.