Klaas Enno Stephan & Rosalyn J. Moran
Wellcome Trust Cente for Neuroimaging Neuroscience, Institute of Neurology, UCL, UK
Wednesday 12 December 2007
Seminar Room B10 (Basement)
Alexandra House, 17 Queen Square, London, WC1N 3AR
Towards neurocomputational models for investigating & diagnosing psychiatric diseases
This presentation will outline a research program that combines neuroimaging, electrophysiology, biophysical modeling and pharmacological manipulations to establish model-based indices of neurophysiological processes as diagnostic markers for psychiatric diseases and high-level cognitive functions therein, such as learning and decision making. The modeling approach rests on Dynamic Causal Modeling (DCM), a framework for analyzing effective synaptic connectivity in the human brain, which characterizes mechanisms in non-linear neural systems perturbed by experimentally designed inputs. After briefly reviewing current pathophysiological concepts of psychiatric diseases (particularly with regard to schizophrenia) and the conceptual foundations of DCM, some preliminary results from ongoing validation studies will be presented. These studies are performed in rodents and designed to test whether currently available DCMs are capable of correctly inferring the state of specific neurophysiological processes, i.e. spike-frequency adaptation and specific forms of short-term synaptic plasticity, from measured responses of larger neuronal populations.