Cerebellar transcranial direct current stimulation impairs the practice-dependent proficiency increase in working...

Area of Science:

• Neuroscience
• Cognitive Science
• Neurostimulation

Background:

• The cerebellum's role in non-motor function, particularly working memory (WM) practice, remains incompletely understood.
• Investigating cerebellar involvement in skill acquisition for cognitive tasks is crucial for understanding brain function.

Purpose of the Study:

• To determine if cerebellar transcranial direct current stimulation (tDCS) affects practice-dependent improvements in a verbal working memory task.
• To compare the effects of cerebellar tDCS with prefrontal cortex tDCS on working memory proficiency.

Main Methods:

• Healthy subjects received anodal or cathodal cerebellar tDCS during a working memory task (Sternberg test).
• Visual evoked potentials (VEPs) were assessed to investigate visual system involvement.
• Comparisons were made with prefrontal cortex tDCS effects on the same task.

Main Results:

• Cerebellar tDCS (anodal or cathodal) significantly impaired practice-dependent improvements in reaction times for the working memory task.
• tDCS over the prefrontal cortex immediately altered task performance but did not affect practice-dependent gains.
• Cerebellar tDCS did not alter VEPs, suggesting the effect is not due to visual processing changes.

Conclusions:

• Transcranial direct current stimulation over the cerebellum specifically hinders the development of proficiency in verbal working memory through practice.
• The cerebellum's role in learning and skill acquisition for cognitive functions is distinct from immediate performance modulation.
• These findings highlight the cerebellum's specific contribution to the practice-dependent enhancement of working memory.