Repetitive Electric Stimulation Elicits Enduring Improvement of Sensorimotor Performance in Seniors

Figure 2

Gain in tactile acuity as a function of baseline performance. Plotted are percent changes (respective post session compared to pre session) in two-point discrimination (2pd) thresholds. (a) Although two-point discrimination thresholds of all fingers were reduced after the first application of rES (post), no correlation between initial threshold level and gain in performance was found (Pearson-correlation, $r$ = $-0.026,\mathrm{\hspace{0.17em}\hspace{0.17em}}P$ = $.884$). In contrast, during succeeding sessions, a significant correlation emerged, which was maintained up to 2 weeks after termination of rES ((b) post-w2 $(r$ = $-0.499,\mathrm{\hspace{0.17em}\hspace{0.17em}}P$ = $.002);$ (c) post-w3 $(r$ = $-0.508,\mathrm{\hspace{0.17em}\hspace{0.17em}}P$ = $.002);$ (d) post-w4 $(r$ = $-0.545,\mathrm{\hspace{0.17em}\hspace{0.17em}}P$ = $.001);$ (e) rec-w1 $(r$ = $-0.461,P$ = $.005);$ (f) rec-w2 $(r=-0.530,\mathrm{\hspace{0.17em}\hspace{0.17em}}P$ = $.001)$).

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