Competitive state of movements during planning predicts sequence performance.

Area of Science:

• Motor control and learning
• Cognitive neuroscience
• Human movement science

Background:

• Skilled movement sequence production from memory is crucial but poorly understood.
• Existing models propose parallel activation and competition for movement selection.
• The link between this planning mechanism and sequence fluency/accuracy remains unclear.

Purpose of the Study:

• To investigate the behavioral relevance of movement availability during motor sequence preparation.
• To determine if movement competition predicts sequence production skill and accuracy.
• To differentiate the role of competitive preactivation from temporal structure in sequence planning.

Main Methods:

• Three multisession experiments with healthy participants.
• Training participants to retrieve and produce four-element finger press sequences from memory.
• Assessing movement availability using reaction time and error rates to movement probes.

Main Results:

• Longer preparation times increased availability differences between adjacent elements.
• Sequence speed and temporal grouping did not affect movement availability differences.
• Greater position-dependent availability differences correlated with faster initiation and higher temporal accuracy.

Conclusions:

• Competitive preactivation during sequence planning develops gradually and predicts motor skill.
• Behavioral measures of movement availability reflect sequence preparedness, not temporal structure.
• Movement availability serves as a marker for sequence planning capacity and skill acquisition.