Is prepulse modification altered by continuous theta burst stimulation? DAT1 genotype and motor threshold interact on prepulse modification following brain stimulation.

Previous studies suggest an inhibitory top-down control of the amygdala by the prefrontal cortex (PFC). Both brain regions play a role in the modulation of prepulse modification (PPM) of the acoustic startle response by a pre-stimulus. Repetitive transcranial magnetic stimulation (rTMS) can modulate the activity of the PFC and might thus affect PPM. This study tested the effect of inhibitory rTMS on PPM accounting for a genetic variant of the dopamine transporter gene (DAT1). Healthy participants (N = 102) were stimulated with continuous theta burst stimulation (cTBS, an intense form of inhibitory rTMS) or sham treatment over the right PFC. Afterwards, during continuous presentation of a background white noise a louder noise burst was presented either alone (control startle) or preceded by a prepulse. Participants were genotyped for a DAT1 variable number tandem repeat (VNTR) polymorphism. Two succeeding sessions of cTBS over the right PFC (2 × 600 stimuli with a time lag of 15 min) attenuated averaged prepulse inhibition (PPI) in participants with a high resting motor threshold. An attenuation of PPI induced by prepulses with great distances to the pulse (480, 2000 ms) was observed following active cTBS in participants that were homozygous carriers of the 10-repeat-allele of the DAT1 genotype and had a high resting motor threshold. Our results confirm the importance of the prefrontal cortex for the modulation of PPM. The effects were observed in participants with a high resting motor threshold only, probably because they received a higher dose of cTBS. The effects in homozygous carriers of the DAT1 10-repeat allele confirm the relevance of dopamine for PPM. Conducting an exploratory study we decided against the use of a correction for multiple testing.

[Repetitive transcranial magnetic stimulation (rTMS) for anxiety disorders--a possible therapeutic option?]. / Repetitive transkranielle Magnetstimulation (rTMS) bei Angsterkrankungen--eine mögliche Therapieoption?

Anxiety disorders rank among the most frequent psychiatric disorders. Effective psychotherapeutic and psychopharmacological interventions exist, although a considerable number of patients does not respond to standard interventions. Repetitive transcranial magnetic stimulation (rTMS) is capable of modulating cortical activity locally and non-invasively. Therefore, rTMS is discussed as a possible alternative treatment approach in psychiatric disorders. The present paper aims to provide a systematic review of randomised controlled studies, open studies, and case reports examining the potential therapeutic effects of rTMS in anxiety disorders. Overall, these studies suggest beneficial effects of rTMS on anxiety symptoms. Nevertheless, larger randomised controlled studies are warranted to allow a more comprehensive evaluation of the therapeutic efficacy of rTMS in anxiety disorders.

Therapy-refractory panic: current research areas as possible perspectives in the treatment of anxiety.

Panic disorder (PD) is characterized by recurrent panic attacks that are defined as distinct episodes of intense fear, accompanied by symptoms related to physical arousal. Because most patients interpret these symptoms as signs of serious somatic disease (e.g., a heart attack), utilization of healthcare services is high in PD sufferers. PD can become debilitating, interfering significantly with patients' lives. Fortunately, effective treatments are available, but a considerable proportion of patients do not respond sufficiently. The aim of this paper is to outline some promising research strategies aimed at improving established treatments.