ABSTRACT
BACKGROUND: Schizophrenia is a severe and often difficult to treat psychiatric illness. In many patients, negative symptoms dominate the clinical picture. Meta-analysis has suggested moderate, but significant effects of high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) on these symptoms. For treatment of depression a much shorter protocol - intermittent theta burst stimulation (iTBS) - has shown to be non-inferior to conventional high-frequency rTMS. This randomized, sham-controlled, rater-blinded clinical trial assesses the effects of conventional HF-rTMS as well as of iTBS of the left dorsolateral prefrontal cortex in comparison with sham. METHODS: The study will be conducted at two psychiatric university hospitals in Germany and at two in the Czech Republic. Assuming an effect size of 0.64 to be detected with a power of 80%, the calculated sample size is 90 patients. Primary outcome will be the difference in the Scale for the Assessment of Negative Symptoms (SANS) score between each active arm and the sham arm at end of treatment.In addition, the trial investigates effects on depressive symptoms, cognitive performance and cigarette smoking. Recording magnetic resonance imaging (MRI) and electroencephalography (EEG) data will serve to assess whether treatment success can be predicted by neural markers and is related to specific neurobiological changes. DISCUSSION: This is a clinical trial directly comparing 10 Hz-rTMS and iTBS in a sham-controlled manner in treating negative symptoms of schizophrenia. If successful, this would present an interesting treatment option for a chronic and severe condition that can be applied at most psychiatric hospitals and only takes up a few minutes per day. TRIAL REGISTRATION NUMBER: This trial has been registered at clinicaltrials.gov, Identifier: NCT04318977. DATA DISSEMINATION: Results from the trial shall be published in peer-reviewed journals and presented at meetings and conferences.
ABSTRACT
Long-term intensive sensorimotor training alters functional representation of the motor and sensory system and might even result in structural changes. However, there is not much knowledge about how previous training impacts learning transfer and functional representation. We tested 14 amateur pianists and 15 musically naïve participants in a short-term finger sequence training procedure, differing considerably from piano playing and measured associated functional representation with functional magnetic resonance imaging. The conditions consisted of encoding a finger sequence indicated by hand symbols ("sequence encoding") and subsequently replaying the sequence from memory, both with and without auditory feedback ("sequence retrieval"). Piano players activated motor areas and the mirror neuron system more strongly than musically naïve participants during encoding. When retrieving the sequence, musically naïve participants showed higher activation in similar brain areas. Thus, retrieval activations of naïve participants were comparable to encoding activations of piano players, who during retrieval performed the sequences more accurately despite lower motor activations. Interestingly, both groups showed primary auditory activation even during sequence retrieval without auditory feedback, supporting previous reports about coactivation of the auditory cortex after learned association with motor performance. When playing with auditory feedback, only pianists lateralized to the left auditory cortex. During encoding activation in left primary somatosensory cortex in the height of the finger representations had a predictive value for increased motor performance later on (error rates). Contrarily, decreased performance was associated with increased visual cortex activation during encoding. Our study extends previous reports about training transfer of motor knowledge resulting in superior training effects in musicians. Performance increase went along with activity in motor areas and the mirror neuron network during pattern encoding.
