The coding of repetitions and alternations in action sequences: spatial or relational?

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human-Computer Interaction

Background:

• Understanding how the brain processes sequential actions is crucial for explaining cognitive control.
• The Simon task is a widely used paradigm to investigate response selection and conflict.
• Distinguishing between spatial and relational coding provides insights into the underlying neural mechanisms.

Purpose of the Study:

• To investigate whether sequential keypresses are encoded using spatial or relational codes.
• To determine how response repetitions and alternations influence the Simon effect.
• To differentiate the coding mechanisms for sequential responses in cognitive tasks.

Main Methods:

• Utilized variants of the Simon task with single-response, response-repetition, and response-alternation conditions.
• Employed different imperative stimuli across three experiments.
• Measured Simon effects in response times for the first keypress in each sequence.

Main Results:

• Simon effects were observed in all conditions.
• The Simon effect increased significantly in the response-alternation condition compared to the single-response condition.
• No significant increase in the Simon effect was found for the response-repetition condition.

Conclusions:

• Response repetitions appear to be coded using relational mechanisms.
• Response alternations seem to be encoded via spatial mechanisms.
• These findings differentiate the coding strategies employed for sequential motor responses.