Corticospinal Plasticity in Bilateral Primary Motor Cortices Induced by Paired Associative Stimulation to the Dominant Hemisphere Does Not Differ between Young and Older Adults

Figure 5

Average MEP change relative to each individual’s baseline (pre-PAS MEP) for young and older LTP- and LTD-like responders in the attend left condition. MEP amplitudes increased significantly in LTP-like responders and decreased significantly in LTD-like responders. Although there was no difference in MEP amplitude change induced in the target (stimulated) and nontarget (unstimulated) hemispheres in LTD-like responders, there was a significant difference between the hemispheres in LTP-like responders. PAS-induced corticospinal plasticity was significant only in the target hemisphere in both LTP- and LTD-like responders. Error bars denote SEM.

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