On behalf of the WPA “Psychiatric Electrophysiology” Section, we would like to submit the following symposium proposal to debate about the usefulness of different electrophysiological tools in psychiatric daily clinical practice. In this view, Pr. Pogarell (Chair of the Section, Germany) will present a general overview about the role of the standard electroencephalogram and the use of event-related potentials (ERPs) in the diagnosis and the management of psychiatric disorders. Then, three more specific communications will follow, illustrating the impact that different neurophysiological tools may have in facing with specific mental diseases. First, Pr Salisbury (Editor-in-Chief, Clinical Electroencephaolgrapy & Neurosience, USA) will debate about the potential role of neurophysiological biomarkers for detection of incipient schizophrenia. Then, Dr Campanella (ECNS Roy John Award 2015, Belgium) will focus on cognitive ERPs biomarkers of relapse in addictive disorders. Finally, Dr Baeken (member of the Multidisciplinary Research Partnership on the Integrative Neuroscience of Behavioral Control, with a focus on Psychiatry Imaging) will illustrate the impact of neuromodulation (tDCS) and/or theta burst stimulation in major depressive disorders.

The neurobiological characterization of patients is a major issue in psychiatry and can help to facilitate diagnostic and prognostic decisions. Furthermore, pathophysiological hypotheses with respect to brain functional activity provide a scientific basis for therapeutic approaches. The assessment of brain activity at rest (EEG) or upon stimulation (ERP) and the investigation of underlying neurochemical properties allow a brain functional characterization of psychiatric disorders and thus the monitoring of treatment effects. Diagnostic, therapeutic and predictive implications of these techniques will be discussed.

Psychotic disorders are neurodevelopmental disorders with active pathology prior to psychotic break. There is no test to detect disease presence prior to psychosis. Among clinical high risk individuals with attenuated symptoms (CHR) only 20-30% will suffer full psychosis. Thus, identification of true prodromal individuals is crucial for early intervention to prevent psychosis. We have developed several putative electrophysiological biomarkers of disease presence, all impaired at first psychosis. These include complex mismatch negativity (cMMN), N1 modulation with attention (Nd), emitted P3b, and the auditory segmentation potential (ASP). Current work in CHR will determine their utility as biomarkers predictive for psychotic disorders.

Dr. Campanella (University of Brussels, Belgium) will highlight an event related potential (ERP) study testing whether the inhibitory No-Go P300 and/or the oddball P300 components can help in recently detoxified alcoholic patients to predict which ones are at higher risk of relapse within the 3 months following detoxification. The impact of anti-craving medication (naltrexone, acamprosate, baclofen) vs. placebo will be discussed.

Pr. Baeken will talk on the impact of accelerated high frequency rTMS on the GABA system in treatment resistant depressed patients. The observed GABA concentration increases after real stimulation suggests that the immediate therapeutic effects of aHF-rTMS are mediated through a locally increased GABAergic inhibitory neurotransmission.