Stimulus-dependent deliberation process in left- and right-handers obtained via current source density analysis.

Area of Science:

• Neuroscience
• Cognitive Psychology
• Human Motor Control

Background:

• Handedness influences brain lateralization and motor control.
• The Stroop task is a common paradigm for studying cognitive control and decision-making.
• High-density electroencephalography (EEG) allows for detailed temporal and spatial analysis of brain activity.

Purpose of the Study:

• To compare electroencephalographic (EEG) activity patterns between right-handed (RH) and left-handed (LH) individuals during a complex deliberation task.
• To investigate how handedness affects neural processing during a two-step decision-making process involving motor responses.
• To analyze the temporal dynamics of brain activity associated with different trial types (go/no-go, response selection).

Main Methods:

• High-density electroencephalography (EEG) recordings were used to capture brain activity.
• Participants (25 RH, 20 LH) performed a color-word Stroop task requiring key presses.
• Task involved discriminating between go-trials (respond) and no-go trials (withhold response), and selecting the appropriate finger for response.

Main Results:

• Temporal activity patterns in RH and LH subjects were highly similar in both shape and component.
• The deliberation process appears to involve a two-step decision: first, deciding whether to move or not (go vs. no-go), and second, selecting the specific finger for the motor response.
• The second decision stage, involving finger selection, was particularly trackable via the local spread of scalp activity.

Conclusions:

• The neural mechanisms underlying this two-step decision-making process during a deliberation task are largely consistent between right-handed and left-handed individuals.
• Handedness does not significantly alter the fundamental temporal activity patterns or the two-step decision architecture observed in this EEG study.
• The findings provide insights into the processing of complex decisions and motor control, highlighting the role of localized brain activity in response selection.