Table 1.

Interhemispheric inhibition (IHI): stimulation parameters

Parameter	Prone	Supine
Unadjusted
TS	44.8 ± 4 (102 ± 5 RMT)	43.6 ± 4 (98 ± 6 RMT)
CS	50.7 ± 10 (117 ± 16 RMT)	52.1 ± 8 (121 ± 11 RMT)

	Prone
	Baseline	ABD	ADD
Adjusted
TS	45.3 ± 6	47.5 ± 8	50.3 ± 9 (F = 11.3, P < 0.001)
CS	80.6 ± 10	50.5 ± 10	77.5 ± 10 (F = 14.2, P < 0.001)
Test MEP	2.6 ± 0.6 mV	2.3 ± 0.8 mV	2.2 ± 0.9 mV (F = 1.1, P = 0.3)
MEP elicited by the CS	3.2 ± 1.9 mV	3.4 ± 1.8 mV	3.3 ± 1.8 mV (F = 1.6, P = 0.2)

Mean stimulus intensity (±SD) used for the test stimulus (TS) and conditioning stimulus (CS) during IHI testing when measurements were completed without adjusting (Unadjusted) or adjusting (Adjusted) the size of the Test MEP and the MEP elicited by the CS. In the unadjusted condition, the same stimulus intensity was used across conditions, with the right hand tested in both prone and supine postures. In the adjusted condition, the intensity values of the TS and CS were changed to acquire a Test MEP of around 2 mV and an MEP elicited by the CS similar to the baseline condition with the right hand in prone posture. Note that there were no differences in the size of the Test MEP and in the MEP elicited by the CS when IHI was tested across conditions (Baseline = right index finger remained at rest; ABD = 30% of right index finger abduction; and ADD = 30% of right index finger adduction).