Noninvasive transcranial direct current stimulation over the left prefrontal cortex facilitates cognitive flexibility...

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neurostimulation

Background:

• Emerging neuroscience research indicates that decreased sensory filtering, linked to reduced cognitive control, may benefit higher-order cognitive tasks.
• Neuroimaging studies provide a foundation for exploring the neural mechanisms underlying cognitive flexibility and control.

Purpose of the Study:

• To investigate whether cathodal (inhibitory) transcranial direct current stimulation (tDCS) enhances performance in a flexible use generation task.
• To test the hypothesis that reduced cognitive control, induced by tDCS, facilitates creative output.

Main Methods:

• Participants received cathodal tDCS (1.5 mA) over the left or right prefrontal cortex (PFC), or sham stimulation, while performing a task requiring generation of common or uncommon uses for objects.
• A forward digit span task was used as a control to assess general stimulation effects.
• Voice-onset reaction times and response generation quantity were measured.

Main Results:

• Left PFC stimulation significantly facilitated the generation of uncommon uses, indicating enhanced cognitive flexibility.
• No significant effects were observed for the common use generation task or the control task.
• Right PFC stimulation did not yield significant performance changes.

Conclusions:

• The findings support the hypothesis that diminishing cognitive control via left PFC tDCS can improve performance on tasks demanding divergent thinking and creativity.
• These results suggest a nuanced role for cognitive control, where reduction can be beneficial for specific higher-order cognitive functions.