Highlights:

• Voluntary, rhythmic, stereotyped, automated motor activities are basic to humans
• Participants did initial submaximal tapping at low and high target tapping rates
• Subsequently, they tapped at a freely chosen rate
• The freely chosen rate was relatively low following the initial low tapping rate
• The freely chosen tapping rate was found to be history dependent

Objective: To test the following hypothesis. Initial submaximal tapping at preset relatively low and high target tapping rates causes a subsequent freely chosen tapping rate to be relatively low and high, respectively, as compared with a reference freely chosen tapping rate.
Methods: Participants performed three 3-min bouts of submaximal index finger tapping on separate days. In one bout (C, considered reference), the rate was freely chosen, throughout. In another bout (A), initial tapping was performed at a relatively low target rate and followed by freely chosen tapping. In yet another bout (B), initial tapping was performed at a relatively high target rate, followed by freely chosen tapping.
Results: At the end of bout A, the rate was 14.6±23.7% lower than the reference value during bout C (p = 0.023). At the end of bout B, the rate was similar to the rate during bout C (p = 0.804).
Conclusions: Initial tapping at a preset relatively low target rate caused a subsequent freely chosen rate to be lower than a reference freely chosen rate. The observation was denoted a phenomenon of motor behavioural history dependence. Initial tapping at a preset relatively high target rate did not elicit history dependence.

Abstract

Background: To test the hypothesis that a 20-s bout of unilateral index finger tapping, followed by 10 min rest, increases the freely chosen tapping rate performed by the contralateral index finger, in a second 20-s bout.

Methods: Twenty healthy adults performed tapping with the index finger on one hand followed by a 10 min rest period and tapping with the other index finger. Tapping was performed at freely chosen rate. Testing was performed with dominant hand first as well as in the opposite order.

Results: Freely chosen tapping rates from the first bouts were 161.6±94.2 and 162.8±80.3 taps per min for the dominant and non-dominant hand, respectively (p=0.903; R=0.89, p<0.001). When bout one was performed with the non-dominant hand, the rate increased by 15.0%±22.3% in about two (p=0.008). In the opposite order, the rate remained similar (+4.8%±17.9%, but p=0.655).

Conclusion: Based on the present, as well as previously published results, the interpretation is that 20 s of initial index finger tapping appears to constitute a borderland for elicitation of subsequent contralateral excitation of freely chosen tapping rate.