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to several important insights. First, these findings ACKNOWLEDGMENTS
indicated that in individuals with dyslexia, the
left superior temporal gyrus, and the left inferior We thank Prof. Jenny Thomson, Harvard Graduate
parietal lobule did not have the same role when School of Education, Cambridge, MA, USA, for vivid
words, nonwords, and texts were read. Second, an discussions on dyslexia that eventually resulted in the
important finding is that not only were left-lateralized writing of the present review paper. Moreover, we thank
improvements found in individuals with dyslexia, Dr. Heike Staudte from the LVR-Klinik Bedburg-Hau,
as one would expect, but also right inferior parietal Kleve, Germany, for her insights regarding the possible
lobule involvement, suggesting that additional clinical applications of high-frequency rTMS in
compensatory recruitment [57] exists in this area, were individuals with dyslexia.
found in those individuals. For the first time, these
results showed that distinctive facilitation of specific REFERENCES
neural pathways (that were previously found to be
less active in individuals with dyslexia) [57] transitorily 1. Bolognini N, Pascual‑Leone A, Fregni F. Using non‑invasive brain
stimulation to augment motor training‑induced plasticity. J Neuroeng
improves the reading of words and texts, which is Rehabil 2009;6:8.
a fascinating finding, and could have far-reaching 2. Devlin JT, Watkins KE. Stimulating language: insights from TMS.
implications, for instance, the development of new Brain 2007;130:610‑22.
treatments for dyslexia. [58] 3. Jahanshahi M, Rothwell J. Transcranial magnetic stimulation studies
of cognition: an emerging field. Exp Brain Res 2000;131:1‑9.
4. Pascual‑Leone A, Walsh V, Rothwell J. Transcranial magnetic
CONCLUSION stimulation in cognitive neuroscience‑virtual lesion, chronometry,
and functional connectivity. Curr Opin Neurobiol 2000;10:232‑7.
The primary aim of this study was to determine the 5. Barker AT, Jalinous R, Freeston IL. Non‑invasive magnetic
stimulation of human motor cortex. Lancet 1985;1:1106‑7.
contributions that TMS has made to different reading 6. Barker AT, Freestone IL, Jalinous R, Merton PA, Morton HB.
modalities. The second goal was to investigate whether Magnetic stimulation of the human brain. J Physiol 1985;369:3P.
TMS might be used as a future intervention technique 7. Pascual‑Leone A, Bartres‑Faz D, Keenan JP. Transcranial magnetic
to overcome reading problems associated with dyslexia. stimulation: studying the brain‑behaviour relationship by
induction of ‘virtual lesions’. Philos Trans R Soc Lond B Biol Sci
We have seen that rTMS turned out to be a valuable tool 1999;354:1229‑38.
for investigating questions related to reading research, 8. McCann UD, Kimbrell TA, Morgan CM, Anderson T, Geraci M,
both on the word and the sentence-level. Moreover, it Benson BE, Wassermann EM, Willis MW, Post RM. Repetitive
can be applied successfully in research on dyslexia. transcranial magnetic stimulation for posttraumatic stress disorder.
Arch Gen Psychiatry 1998;55:276‑9.
Recently, (high-frequency) rTMS has been used as a 9. Pascual‑Leone A, Valls‑Solé J, Wassermann EM, Hallett M.
“clinical” intervention technique for treating dyslexia Responses to rapid‑rate transcranial magnetic stimulation of the
by improving the reading performance by exciting human motor cortex. Brain 1994;117:847‑58.
underactive reading pathways in the brain. This seems 10. Pascual‑Leone A, Rubio B, Pallardó F, Catalá MD. Rapid‑rate
transcranial magnetic stimulation of left dorsolateral prefrontal cortex
to be a very promising direction for developing new in drug‑resistant depression. Lancet 1996;348:233‑7.
and better treatments for dyslexia [Figure 2a], as long 11. Zimerman M, Hummel FC. Non‑invasive brain stimulation:
as the safety of the individuals with dyslexia can be enhancing motor and cognitive functions in healthy old subjects.
Front Aging Neurosci 2010;2:149.
guaranteed and strict guidelines on brain stimulation 12. Freitas C, Farzan F, Pascual‑Leone A. Assessing brain plasticity across
are followed. [60,61] the lifespan with transcranial magnetic stimulation: why, how, and
what is the ultimate goal? Front Neurosci 2013;7:42.
Moreover, a new development, the combination 13. Hamada M, Ugawa Y, Tsuji S; Effectiveness of rTMS on Parkinson’s
of brain stimulation by TMS with simultaneous Disease Study Group, Japan. High‑frequency rTMS over the
electroencephalographic (EEG) imaging, [62,63] offers supplementary motor area improves bradykinesia in Parkinson’s
disease: subanalysis of double‑blind sham‑controlled study. J Neurol
new prospects for research on reading and dyslexia. Sci 2009;287:143‑6.
The integration of TMS with EEG is able to give 14. Pascual‑Leone A, Gates JR, Dhuna A. Induction of speech arrest and
information on the causal link between brain activity counting errors with rapid‑rate transcranial magnetic stimulation.
Neurology 1991;41:697‑702.
and its underlying function and cortical reactivity 15. Wada J, Rasmussen T. Intracarotid injection of sodium amytal for
and its connection with other areas in the brain. More the lateralization of cerebral speech dominance: experimental and
importantly, it also gives a better time window on clinical observations. J Neurosurg 1960;17:266‑82.
when particular neural actions occur in the brain. [63] 16. Loddenkemper T, Morris HH, Möddel G. Complications during the
Wada test. Epilepsy Behav 2008;13:551‑3.
Therefore, this integration of TMS with EEG will 17. Rösler J, Niraula B, Strack V, Zdunczyk A, Schilt S, Savolainen P,
give important additional neural information on Lioumis P, Makela J, Vajkoczy P, Frey D, Picht T. Language mapping
reading abnormalities in individuals with dyslexia, in healthy volunteers and brain tumor patients with a novel
as well as on the efficiencies and the underlying navigated TMS system: evidence of tumor‑induced plasticity. Clin
Neurophysiol 2014;125:526‑36.
working mechanisms of future TMS dyslexia 18. Epstein CM. Transcranial magnetic stimulation: language function.
treatments [Figure 2b]. J Clin Neurophysiol 1998;15:325‑32.
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