Footnotes

• PDV and EL contributed equally.

• Contributors PDV designed and conceptualised the study, analysed and interpreted all data, and drafted and submitted the manuscript. GJBE and AB played a major role in the acquisition of data and imaging analysis, and critically reviewed the manuscript. EL, KS, PG and DBW played a major role in the acquisition of the psychometric data and reviewed the manuscript. NL and AL designed and conceptualised the study, revised the manuscript and are responsible for the overall content as guarantors.

• Funding This study was funded by the Klarman Family Foundation (2012 and 2013 one year awards to AML) and the Canadian Institutes of Health Research (2011 to 2014 CIHR fellowship to NL and AML).

• Competing interests Dr. De Vloo has received grants from Research Fund-Flanders, the European Society for Stereotactic and Functional Neurosurgery, the Helaers Foundation, Medtronic, Boston Scientific, and St Jude-Abbott. Dr. Sutandar has received grants from the Klarman Family Foundation and the Canadian Institutes of Health Research. Dr. Lozano has received personal fees from Medtronic, Boston Scientific, St Jude-Abbott, and Functional Neuromodulation.

• Provenance and peer review Not commissioned; internally peer reviewed.

• Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.