Corticolimbic hyper-response to emotion and glutamatergic function in people with high schizotypy: A multimodal fMRI-MRS study

Animal models and human neuroimaging studies suggest that altered levels of glutamatergic metabolites within a corticolimbic circuit have a major role in the pathophysiology of schizophrenia. Rodent models propose that prefrontal glutamate dysfunction could lead to amygdala hyper-response to environmental stress and underlie hippocampal overdrive in schizophrenia. Here we determine whether changes in brain glutamate are present in individuals with high schizotypy (HS), which refers to the presence of schizophrenia-like characteristics in healthy individuals, and whether glutamate levels are related to altered corticolimbic response to emotion. Twenty-one healthy HS subjects and 22 healthy subjects with low schizotypy (LS) were selected based on their Oxford and Liverpool Inventory of Feelings and Experiences rating. Glutamate levels were measured in the anterior cingulate cortex (ACC) using proton magnetic resonance spectroscopy, followed by a functional magnetic resonance imaging (fMRI) scan to measure corticolimbic response during emotional processing. fMRI results and fMRI × glutamate interactions were considered significant after voxel-wise P<0.05 family-wise error correction. While viewing emotional pictures, HS individuals showed greater activation than did subjects with LS in the caudate, and marginally in the ACC, hippocampus, medial prefrontal cortex (MPFC) and putamen. Although no between-group differences were found in glutamate concentrations, within the HS group ACC glutamate was negatively correlated with striatal activation (left: z=4.30, P=0.004 and right: z=4.12 P=0.008 caudate; left putamen: z=3.89, P=0.018) and marginally with MPFC (z=3.55, P=0.052) and amygdala (left: z=2.88, P=0.062; right: z=2.79, P=0.079), correlations that were not present in LS subjects. These findings provide, to our knowledge, the first evidence that brain glutamate levels are associated with hyper-responsivity in brain regions thought to be critical in the pathophysiology of psychosis

Verhaltensmedizin, Psychotherapie und Zahnheilkunde

Biological, psychological and social processes are of relevance in the development and treatment of dental disorders. However, knowledge about interactions among these factors has only few implications for clinical practice. Hence, the goal of this article is to provide an overview of the links between behavioral medicine, psychotherapy and dentistry. The biobehavioral implications of different dental illnesses and disorders (caries, gingivitis, periodontitis, burning-mouth syndrome, and halitosis) as well as biobehavioral characteristics of specific patient groups are presented. The existing scientific knowledge in the interdisciplinary field of behavioral medicine, psychotherapy and dentistry provides the basis for a variety of treatment approaches. Its efficacy has, in part, already been confirmed. The integration of knowledge on psychobiological processes underlying psychotherapy and dental illnesses may lead to new interventions, based on the concept of neuropsychotherapy. It can be expected that further studies on the efficacy and effectiveness of specific biobehavioral interventions will significantly contribute to an increase in oral health