A multi-representation approach to the contextual interference effect: effects of sequence length and practice

Area of Science:

• Motor learning and control
• Cognitive psychology
• Human motor behavior

Background:

• The contextual interference (CI) effect in motor learning describes how practice schedules influence skill acquisition.
• Previous research has yielded mixed results regarding the long-term benefits of random practice (RP) over blocked practice (BP).
• Factors like sequence length and practice amount may moderate the CI effect.

Purpose of the Study:

• To investigate the long-term benefits of RP versus BP for motor learning.
• To examine how motor sequence length and practice amount influence the CI effect.
• To test predictions from the Cognitive framework of Sequential Motor Behavior (C-SMB).

Main Methods:

• Two experiments using the Discrete Sequence Production (DSP) task.
• Comparison of limited and extended practice amounts for 4- and 7-key sequences.
• Assessment of 24-hour delayed retention performance under RP and BP schedules.

Main Results:

• The CI effect, favoring RP, was observed only for short sequences with limited practice, supporting C-SMB predictions.
• Limited practice under RP enhanced both reaction and chunking modes of sequence execution.
• Extended practice, regardless of schedule (RP or BP), led to equivalent sequence representation development for 7-key sequences.
• Greater explicit awareness of sequence structures correlated with faster performance on practiced and novel sequences.

Conclusions:

• The long-term benefit of RP over BP is contingent on sequence length and practice amount.
• Limited practice with RP facilitates motor memory consolidation and enhances implicit/explicit sequence representation.
• Explicit awareness of sequence structures is crucial for efficient motor sequence execution across different practice conditions.