High frequency rTMS over the left parietal lobule increases non-word reading accuracy

Area of Science:

• Neuroscience
• Cognitive Science
• Psycholinguistics

Background:

• Reading involves complex cognitive processes, including phonological decoding.
• The left superior temporal gyrus (STG) and left inferior parietal lobe (IPL) are critical for phonological processing during reading.
• Transcranial Magnetic Stimulation (TMS) is a valuable tool for investigating brain function in reading.

Purpose of the Study:

• To elucidate the distinct roles of the left IPL and STG in reading aloud.
• To assess the impact of high-frequency repetitive TMS (hf-rTMS) on reading performance in healthy individuals.
• To determine if hf-rTMS can modulate reading accuracy in a task- and site-specific manner.

Main Methods:

• Healthy participants underwent high-frequency repetitive Transcranial Magnetic Stimulation (hf-rTMS).
• Stimulation was targeted over the left inferior parietal lobe (IPL) and the right superior temporal gyrus (STG).
• Reading aloud tasks, including non-word and text reading, were administered to assess performance changes.

Main Results:

• hf-rTMS over the left IPL significantly improved non-word reading accuracy.
• hf-rTMS over the right STG led to a decrease in text-reading accuracy.
• These findings highlight the specific roles of the left IPL in grapheme-to-phoneme conversion and the STG in processing textual representations.

Conclusions:

• hf-rTMS effectively modulates reading accuracy in expert readers.
• The observed modulations are dependent on the stimulation site and the specific reading task.
• These results offer potential new avenues for therapeutic interventions in reading disorders.