Trimodal approach (PET/MR/EEG) of response inhibition as a possible biomarker for schizophrenia

Abstract

IntroductionThe aim of the FP7-European funded project TRIMAGE is to create a trimodal, cost-effective imaging tool consisting of PET/MR/EEG to enable effective early diagnosis of schizophrenia.ObjectiveIn the scope of this project we are interested in the multimodal assessment of response inhibition. The loudness dependence of auditory evoked potential (LDAEP) is a suitable biomarker of inhibitory action in signal processing. Variations in response inhibition can have great impact on different aspects of life. Individuals with reduced capability of inhibitory control have a tendency to impulsive behavior. Studies showed that they have stronger LDAEP values. Patients with schizophrenia may exhibit alterations in the responsiveness to sensory stimuli. Thus, a reduced LDAEP was found in these patients. However, these deviances differed in clinical features of the disorder. Therefore, we would like to further elucidate the relationship between multimodal neuroimaging methods and dimensions of symptoms, observable behavior, personality traits and general psychopathological dysfunction.MethodsA sample of 20 healthy controls and 20 patients with manifest schizophrenia will be examined with the LDAEP paradigm in a trimodal approach with customary imaging tools. PET measurements with the radiotracer [11C]-flumazenil will be used to assess the binding potentials of GABA-A receptors. MRS will provide data about GABA concentrations. Simultaneously recorded EEG-fMRI data will permit new insight in the relationship between LDAEP and impulsivity.DiscussionThe project will use alternative approaches to psychiatric classification. Response inhibition in sensory processing will be investigated from different angles (biochemical, neurophysiological, and neuroanatomical) and combined with psychological characteristic values.Disclosure of interestThe authors have not supplied their declaration of competing interest.