When is an odd number not odd? Influence of task rule on the MARC effect for numeric classification

Area of Science:

• Cognitive Psychology
• Human-Computer Interaction
• Number Cognition

Background:

• The linguistic markedness association of response codes (MARC) effect describes enhanced performance when stimulus and response codes align in linguistic markedness.
• Previous research suggests compatibility between stimulus and response codes influences task efficiency.

Purpose of the Study:

• To investigate the MARC effect using Arabic numerals and number words under different task rules (odd-even vs. multiple-of-3).
• To examine how task rules influence the MARC effect and its potential reversal.

Main Methods:

• Two experiments were conducted involving participants classifying numbers (3, 4, 8, 9) using either an odd-even parity rule or a multiple-of-3 rule.
• Keypress responses (left/right) were recorded for both Arabic numerals and number words.

Main Results:

• The MARC effect was observed with the odd-even rule for both stimulus types.
• A reversal of the MARC effect was noted with the multiple-of-3 rule, particularly for right-hand responses.
• The task rule had minimal impact on left-hand responses.

Conclusions:

• The findings support the hypothesis that the MARC effect and its reversal are driven by the correspondence between the stimulus code's positive designation (based on the task rule) and the positive-polarity right response code.
• This suggests a cognitive mechanism linking task rules, stimulus properties, and response selection.