Institut Inserm de rattachement : Neurosciences, Neurologie, Psychiatrie
Institut CEA de rattachement : Institut d'Imagerie BioMédicale : I2BM
Over the past 4 years, researchers of our unity have studied psychiatric disorders and addictions with a high prevalence and social cost. They used magnetic resonance and positron emission tomography in the Service Hospitalier Frédéric Joliot (SHFJ), Orsay, in collaboration with a network of psychiatrists within the Paris area, or data transfers from North Europe research teams.
Brain images in patients severely impaired and effects of treatments on brain function were studied.
- Deficits in brain anatomy and function in the temporal cortex in children with autism, related with the severity of their social impairment.
- Statistical deviations of cortex gyrification and function, notably in the left temporal region, in schizophrenia patients with pharmaco-resistant auditory hallucinations. Temporal cortex deviations in patients with adolescent-onset schizophrenia, precluded a drug treatment bias.
- Higher white matter connectivity and grey matter activation in regions processing emotions in patients who had recovered from a bipolar disorder episode, suggesting persistence of brain vulnerability to emotional cues, even in their remitted state.
All these findings are consistent with altered brain development models of these disorders.
Investigation of treatment or drug effects
Controlled clinical trials of experimental non-invasive magnetic stimulations guided with anatomo-functional neuroimages were completed in pharmaco-resistant patients with depression or schizophrenia. Results suggest treatment effects might vary with patients' brain function and anatomy. A method for individual classification of patient's course based on its neuroimage was tested. The effect of magnetic stimulations of langage-related regions on subjects' performance, was measured.
In tobacco- and cannabis-addict subjects, lower dopamine transporter was detected in basal ganglia and thalamus in both dependences, using ultra high resolution positron tomography. Abnormal reactivity in dopamine brain regions were detected in tobacco-dependents presented with tobacco cues. These brain changes add to the documentation of dependence mechanisms in humans.
- In detoxified alcohol-dependent subjects with preserved social functioning, marked alterations in brain gray and white matter volumes and connectivity were related to the age of first contact with alcohol and to the degradation of their performance. This supports the usefulness of early prevention in adolescents, and of neuropsychological assessment through detox. course.
Prospects for the years to come
Research activities will pursue in both Neurospin and SHFJ platforms. Research will involve clinical departments in Paris Descartes / Paris Centre University (e.g. radiopaediatry in Necker hospital; adult, child and adolescent psychiatry departments), in Paris Sud University (e.g. addictology), and in Orsay hospital.
- Risk factors. Since some mental disorders might be linked with measurable changes in brain structure development, investigations will focus on young subjects with autism spectrum disorder, or at risk for affective disorders, or for addictions (e.g. binge drinking). This objective will be pursued through joint research projects with teams experienced in genomics or epidemiology, in order to tackle relationships between neuroimages and genetic variables.
- Pharmaceutics & drug response. Objective brain descriptors of drugs effects will be searched from both positron tomography and MR images in patients, in SHFJ. Based on our experience of controlled therapeutic trials involving imaging patients with depression or schizophrenia, promoted projects will investigate the brain effects of a catecholamine reuptake inhibitor, of a compound trial for cocaine detox. and of medications used in actual therapeutic setting.