Neuropsychiatric Symptoms of Epilepsy

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of nightly (approximately 8 h/night) bilateral transcutaneous electrical stimulation
of the forehead (V1 trigeminal branch) for 8 weeks (approximately 55 treatment
sessions). A statistically significant reduction in depressive symptoms (both raterand
patient-rated) was reported. Of the 11 TRD patients enrolled, 6 had ≥50 %
reduction in depressive symptoms and 4 achieved symptom remission. Shiozawa
et al. subsequently conducted a randomized, sham-controlled trial of TNS in 40
patients with major depressive disorder using a 10-day intervention protocol [ 84 ].
The investigators found a significant benefit of TNS compared to sham stimulation.
These data are promising, but larger, prospective, double-blind studies of TNS for
TRD are needed.
Transcranial Magnetic Stimulation
Transcranial magnetic stimulation (TMS) is a noninvasive technique that utilizes
brief pulses of electrical current sent to a coiled wire placed over the scalp to deliver
rapidly changing magnetic fields that pass through the scalp and skull to modulate
plasticity and excitability of cortex within the stimulated field. The specific cortical
effects depend on pulse intensity and frequency as well as the targeted area of cortex.
The pulse intensity is usually titrated by first determining the patient’s motorevoked
potential threshold [ 85 ]. TMS is approved for depression in the United
States, Canada, Brazil, Australia, and Israel, and it is also widely used in Europe
[ 86 ]. Most clinical applications of TMS to the treatment of neuropsychiatric symptoms
involve trains of stimulation pulses, called repetitive TMS (rTMS). Low stimulation
frequencies (≤1 Hz) are generally inhibitory while faster frequencies
(≥5 Hz) are usually excitatory.
Patients with Epilepsy
Though a number of studies have evaluated rTMS as a treatment for epilepsy, methodological
weaknesses limit the strength of the available data to “possible efficacy,”
according to European evidence-based guidelines [ 86 ]. Unfortunately, given the
demonstrated benefits of TMS for depression and other psychiatric disorders, effects
on neuropsychiatric symptoms in PWE have not been systematically assessed.
Patients Without Epilepsy
Many studies and meta-analyses have evaluated the use of TMS for depression.
Evidence-based guidelines published by European experts found Level A evidence
(definite efficacy) for an antidepressant effect of high-frequency rTMS administered
to the left DLPFC and Level B (probable efficacy) evidence for an antidepressant
effect of low-frequency rTMS to the right DLPFC [ 86 ]. By contrast, another