title: Combining task-evoked and spontaneous activity to improve pre-operative brain mapping with fMRI.
abstract: Noninvasive localization of brain function is used to understand and treat neurological disease, exemplified by pre-operative fMRI mapping prior to neurosurgical intervention. The principal approach for generating these maps relies on brain responses evoked by a task and, despite known limitations, has dominated clinical practice for over 20years. Recently, pre-operative fMRI mapping based on correlations in spontaneous brain activity has been demonstrated, however this approach has its own limitations and has not seen widespread clinical use. Here we show that spontaneous and task-based mapping can be performed together using the same pre-operative fMRI data, provide complimentary information relevant for functional localization, and can be combined to improve identification of eloquent motor cortex. Accuracy, sensitivity, and specificity of our approach are quantified through comparison with electrical cortical stimulation mapping in eight patients with intractable epilepsy. Broad applicability and reproducibility of our approach are demonstrated through prospective replication in an independent dataset of six patients from a different center. In both cohorts and every individual patient, we see a significant improvement in signal to noise and mapping accuracy independent of threshold, quantified using receiver operating characteristic curves. Collectively, our results suggest that modifying the processing of fMRI data to incorporate both task-based and spontaneous activity significantly improves functional localization in pre-operative patients. Because this method requires no additional scan time or modification to conventional pre-operative data acquisition protocols it could have widespread utility.
authors.affiliation: Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Fox
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China.
authors.forename: Tianyi
authors.initials: T
authors.lastname: Qian
authors.affiliation: Department of Neurosurgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Madsen
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Danhong
authors.initials: D
authors.lastname: Wang
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Meiling
authors.initials: M
authors.lastname: Li
authors.affiliation: Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability, Department of Biomedical Engineering, Hebei University of Technology, Tianjin, China.
authors.forename: Manling
authors.initials: M
authors.lastname: Ge
authors.affiliation: Second Affiliated Hospital of Tsinghua University, Beijing, China.
authors.forename: Huan-Cong
authors.initials: HC
authors.lastname: Zuo
authors.affiliation: Department of Neurosurgery, Hofstra North Shore LIJ School of Medicine, 300 Community Dr., Manhasset, NY 11030, USA; Feinstein Institute for Medical Research, 350 Community Dr., Manhasset, NY 11030, USA; Department of Psychology, University of Toronto, 100 St. George St., Toronto, ON M5S 3G3, Canada.
authors.forename: David M
authors.initials: DM
authors.lastname: Groppe
authors.affiliation: Department of Neurosurgery, Hofstra North Shore LIJ School of Medicine, 300 Community Dr., Manhasset, NY 11030, USA; Feinstein Institute for Medical Research, 350 Community Dr., Manhasset, NY 11030, USA.
authors.forename: Ashesh D
authors.initials: AD
authors.lastname: Mehta
authors.affiliation: Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China. Electronic address: Hongbo@tsinghua.edu.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Hong
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. Electronic address: Hesheng@nmr.mgh.harvard.edu.
authors.forename: Hesheng
authors.initials: H
authors.lastname: Liu
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000295:instrumentation / Q000379:methods*; D015331:Cohort Studies; D017352:Echo-Planar Imaging; D004525:Efferent Pathways / Q000033:anatomy & histology; D004558:Electric Stimulation; D004567:Electrodes, Implanted; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009044:Motor Cortex / Q000033:anatomy & histology / Q000473:pathology / Q000601:surgery; D019635:Neurosurgical Procedures / Q000379:methods; D057234:Preoperative Period; D011597:Psychomotor Performance / Q000502:physiology; D012372:ROC Curve; D015203:Reproducibility of Results; D059629:Signal-To-Noise Ratio; D055815:Young Adult