Abstract
BACKGROUND:
Schizophrenia has been associated with disturbances of thalamic functioning. In the light of recent evidence suggesting a significant impact of the glutamatergic system on key symptoms of schizophrenia, we assessed whether the modulation of the glutamatergic system via blockage of the NMDA-receptor might lead to changes of thalamic functional connectivity.
METHODS:
Based on the “ketamine-model” of psychosis we investigated changes in cortico-thalamic functional connectivity by intravenous ketamine challenge during a 55 minutes resting-state scan. 30 healthy volunteers were measured with pharmacological functional magnetic resonance imaging (fMRI) using a double-blind, randomized, placebo-controlled, crossover design.
RESULTS:
Functional connectivity analysis revealed significant ketamine-specific changes within the “thalamus hub network”, more precisely an increase of cortico-thalamic connectivity of the somatosensory and temporal cortex.
CONCLUSIONS:
Our results indicate that changes of thalamic functioning as described for schizophrenia can be partly mimicked by NMDA-receptor blockage. This adds substantial knowledge about the neurobiological mechanisms underlying the profound changes of perception and behaviour during the application of NMDA-receptor antagonists.
Höflich, A., Hahn, A., Küblböck, M., Kranz, G. S., Vanicek, T., Windischberger, C., … & Guertel, W. (2015). Ketamine-induced modulation of the thalamo-cortical network in healthy volunteers as a model for schizophrenia. The international journal of neuropsychopharmacology. http://dx.doi.org/10.1093/ijnp/pyv040
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