Stimulus-hand correspondence and direct response activation: An electromyographic analysis

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Factors

Background:

• The Simon task reveals cognitive biases in response selection.
• Incorrect activations (IAs) occur when stimulus location conflicts with response location.
• The roles of stimulus-key location and stimulus-hand correspondence in IAs are not fully understood.

Purpose of the Study:

• To investigate the distinct contributions of stimulus-key location correspondence and stimulus-hand correspondence to incorrect activations in the Simon task.
• To determine how arm placement (non-crossing vs. crossing the median plane) affects these contributions.

Main Methods:

• Participants performed a Simon task with arms uncrossed and crossed.
• Incorrect activations (IAs) were measured for congruent and incongruent stimulus-response conditions.
• Latency analyses were conducted to explore processing pathways.

Main Results:

• The difference in IA frequency between incongruent and congruent trials was smaller when arms were crossed.
• Incorrect activations are primarily driven by stimulus-key location correspondence.
• Stimulus-hand correspondence had a lesser influence on IAs.

Conclusions:

• Incorrect activations in the Simon task are predominantly influenced by stimulus-key location correspondence.
• Stimulus-hand correspondence contributes less to IAs and appears to be mediated by intra-hemispheric processing.
• Crossing the arms modulates the impact of stimulus-hand correspondence, potentially by altering neural pathways.