title: Evidence from a rare case study for Hebbian-like changes in structural connectivity induced by long-term deep brain stimulation.
abstract: It is unclear whether Hebbian-like learning occurs at the level of long-range white matter connections in humans, i.e., where measurable changes in structural connectivity (SC) are correlated with changes in functional connectivity. However, the behavioral changes observed after deep brain stimulation (DBS) suggest the existence of such Hebbian-like mechanisms occurring at the structural level with functional consequences. In this rare case study, we obtained the full network of white matter connections of one patient with Parkinson's disease (PD) before and after long-term DBS and combined it with a computational model of ongoing activity to investigate the effects of DBS-induced long-term structural changes. The results show that the long-term effects of DBS on resting-state functional connectivity is best obtained in the computational model by changing the structural weights from the subthalamic nucleus (STN) to the putamen and the thalamus in a Hebbian-like manner. Moreover, long-term DBS also significantly changed the SC towards normality in terms of model-based measures of segregation and integration of information processing, two key concepts of brain organization. This novel approach using computational models to model the effects of Hebbian-like changes in SC allowed us to causally identify the possible underlying neural mechanisms of long-term DBS using rare case study data. In time, this could help predict the efficacy of individual DBS targeting and identify novel DBS targets.
authors.affiliation: Department of Psychiatry, University of Oxford Oxford, UK ; Center of Functionally Integrative Neuroscience (CFIN), Aarhus University Aarhus, Denmark.
authors.forename: Tim J
authors.initials: TJ
authors.lastname: van Hartevelt
authors.affiliation: Department of Psychiatry, University of Oxford Oxford, UK ; Center of Brain and Cognition, Theoretical and Computational Neuroscience Group, Universitat Pompeu Fabra Barcelona, Spain.
authors.forename: Joana
authors.initials: J
authors.lastname: Cabral
authors.affiliation: Center of Functionally Integrative Neuroscience (CFIN), Aarhus University Aarhus, Denmark.
authors.forename: Arne
authors.initials: A
authors.lastname: Møller
authors.affiliation: Nuffield Department of Surgical Sciences, John Radcliffe Hospital Oxford, UK.
authors.forename: James J
authors.initials: JJ
authors.lastname: FitzGerald
authors.affiliation: Nuffield Department of Surgical Sciences, John Radcliffe Hospital Oxford, UK.
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Green
authors.affiliation: Department of Psychiatry, University of Oxford Oxford, UK ; Nuffield Department of Surgical Sciences, John Radcliffe Hospital Oxford, UK.
authors.forename: Tipu Z
authors.initials: TZ
authors.lastname: Aziz
authors.affiliation: Center of Brain and Cognition, Theoretical and Computational Neuroscience Group, Universitat Pompeu Fabra Barcelona, Spain ; Institució Catalana de la Recerca i Estudis Avançats (ICREA), Universitat Pompeu Fabra Barcelona, Spain.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Deco
authors.affiliation: Department of Psychiatry, University of Oxford Oxford, UK ; Center of Functionally Integrative Neuroscience (CFIN), Aarhus University Aarhus, Denmark ; Nuffield Department of Surgical Sciences, John Radcliffe Hospital Oxford, UK.
authors.forename: Morten L
authors.initials: ML
authors.lastname: Kringelbach
keywords: DTI; Hebbian-like learning; Parkinson’s disease; deep brain stimulation; subthalamic nucleus