Relaxing learned constraints through cathodal tDCS on the left dorsolateral prefrontal cortex

Area of Science:

• Cognitive Neuroscience
• Neurostimulation

Background:

• Problem-solving often relies on applying learned rules, a process automated by the dorsolateral prefrontal cortex (DLPFC).
• Cognitive flexibility can be impaired when prior experience creates mental ruts, hindering the ability to adapt problem-solving strategies.

Purpose of the Study:

• To investigate if suppressing the left DLPFC using transcranial direct current stimulation (tDCS) can facilitate representational change.
• To determine if tDCS can help overcome mental blocks caused by ingrained rules.

Main Methods:

• Participants engaged in matchstick arithmetic problems requiring the relaxation of learned constraints.
• Transcranial direct current stimulation (tDCS) was applied to the left DLPFC, with conditions including cathodal, anodal, and sham stimulation.
• Performance on problem-solving tasks was assessed before and after tDCS application.

Main Results:

• Participants receiving cathodal tDCS to the left DLPFC showed a greater ability to solve problems demanding the relaxation of previously learned constraints.
• Compared to anodal or sham tDCS, cathodal stimulation significantly improved performance on tasks requiring representational change.

Conclusions:

• Cathodal tDCS over the left DLPFC may be a viable method for facilitating cognitive flexibility.
• This neurostimulation approach appears to aid in overcoming mental ruts by promoting the relaxation of learned constraints, thereby enabling successful representational change.