**Author details**

most widely used stimulation is high frequency rTMS over the right DLPFC. However, a study by Ustohal et al. [108] showed that this protocol can have a negative effect on patient's depression symptoms and suggests another stimulation site, such as left DLPFC, at least for patients with a personal history of depression. However, this side effect has only been observed in a single patient. Another treatment protocol to consider is low frequency rTMS over the left DLPFC, which could possibly have a similar effect. Hyperactivity symptoms of ADHD could also be reduced by using low frequency rTMS over the SMA; however, only two patients have been stimulated by this protocol, and further research is needed. There is a lack of reliable data on the duration of the therapeutic effect. Further understanding of the neurophysiological mechanisms of the effect and assessment of adequate stimulation parameters are required.

Studies suggest that rTMS is a well-tolerated treatment in patients with ADHD and potentially a highly useful tool for reducing ADHD symptoms including impulsivity, motor hyperactivity, and reduced attention. There are not yet double-blind randomized controlled studies with sufficient sample sizes. The current studies differ substantially in both rTMS cortical targets and stimulation protocols. Most studies suggest stimulation over the right DLPFC by high frequency rTMS; another potentially promising protocol in ADHD is low frequency rTMS over the SMA. More double-blind placebo-controlled studies and evidence about the

The most important application of rTMS for impulsivity reduction in BDP and ADHD seems to be stimulation over the left or right DLPFC, the SMA, or the cerebellum. However, it should be stressed that the neural activity associated with impulsivity differs according to the task parameters used during neuroimaging. This applies for studies of behavioral inhibition, Delay Discounting, and emotion regulation. This problem might be overcome by navigating rTMS individually according to functional fMRI from a specific task administered to the patients before stimulation. rTMS seems to be well tolerated without any adverse events in BPD and ADHD patients. The results of rTMS impulsivity treatment studies are promising, but double-blind studies with larger active and sham group sizes are needed to optimize the

This contribution was supported by the Ministry of Health of the Czech Republic, grant no.

15-30062A. The authors like to thank Ms. Anne Johnson for proof-reading.

**4.4. Summary of rTMS treatment in ADHD**

54 Transcranial Magnetic Stimulation in Neuropsychiatry

**5. Conclusion**

treatment results.

**Acknowledgements**

therapeutic effect of rTMS in ADHD patients are needed.

Tomas Sverak1,2\*, Pavla Linhartova<sup>1</sup> , Adam Fiala1 and Tomas Kasparek<sup>1</sup>

\*Address all correspondence to: tomas.sverak@mail.muni.cz

1 Department of Psychiatry, Masaryk University and University Hospital Brno, Czech Republic

2 Central European Institute of Technology (CEITEC MU), Masaryk University, Brno, Czech Republic
