Functional Activation following Transcranial Magnetic Stimulation in Neurotypical Adult Readers.

Area of Science:

• Neuroscience
• Cognitive Science

Background:

• Transcranial magnetic stimulation (TMS) is a noninvasive technique to modulate brain activity and enhance cognitive functions.
• Research is exploring TMS for reading enhancement, but its immediate effects on brain activity during reading tasks in typical adults need further investigation.
• This study investigates the impact of intermittent theta burst stimulation (iTBS) on brain activity during spoken and written word processing.

Purpose of the Study:

• To explore how offline intermittent theta burst stimulation (iTBS) to left supramarginal gyrus (SMG) or middle temporal gyrus (MTG) affects brain activity during spoken and written word processing.
• To understand the immediate neuromodulatory effects of TMS on the reading network in adults with typical reading skills.

Main Methods:

• A sandwich design TMS-fMRI study involving 25 adults with typical reading skills.
• Participants underwent a baseline fMRI task (picture-word identification), received iTBS to either SMG or MTG, followed by a post-stimulation fMRI session.
• Whole-brain analysis using GLM and paired t-tests identified changes in brain activation patterns.

Main Results:

• TMS modulated brain activity approximately 20 minutes post-stimulation.
• SMG stimulation led to increased activation for spoken words only.
• MTG stimulation enhanced activation for both spoken and written words, within reading and executive control networks.

Conclusions:

• A single offline TMS session can acutely modulate brain activity during spoken and written word processing.
• SMG stimulation selectively impacts auditory word processing, supporting distinct roles for dorsal and ventral reading streams.
• Findings may inform the development of neuromodulatory interventions for reading and language impairments.