title: Spatio-temporal activity in real time (STAR): optimization of regional fMRI feedback.
abstract: The use of real-time feedback has expanded fMRI from a brain probe to include potential brain interventions with significant therapeutic promise. However, whereas time-averaged blood oxygenation level-dependent (BOLD) signal measurement is usually sufficient for probing a brain state, the real-time (frame-to-frame) BOLD signal is noisy, compromising feedback accuracy. We have developed a new real-time processing technique (STAR) that combines noise-reduction properties of multi-voxel (e.g., whole-brain) techniques with the regional specificity critical for therapeutics. Nineteen subjects were given real-time feedback in a cognitive control task (imagining repetitive motor activity vs. spatial navigation), and were all able to control a visual feedback cursor based on whole-brain neural activity. The STAR technique was evaluated, retrospectively, for five a priori regions of interest in these data, and was shown to provide significantly better (frame-by-frame) classification accuracy than a regional BOLD technique. In addition to regional feedback signals, the output of the STAR technique includes spatio-temporal activity maps (movies) providing insight into brain dynamics. The STAR approach offers an appealing optimization for real-time fMRI applications requiring an anatomically-localized feedback signal.
authors.affiliation: Department of Radiology, University of Pennsylvania School of Medicine, 1 Founders Pavilion, MRI Education Center, 3400 Spruce Street, Philadelphia, PA 19104, USA. Jeremy.Magland@gmail.com
authors.forename: Jeremy F
authors.initials: JF
authors.lastname: Magland
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Tjoa
authors.forename: Anna Rose
authors.initials: AR
authors.lastname: Childress
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000033:anatomy & histology* / Q000502:physiology*; D001931:Brain Mapping; D003071:Cognition / Q000502:physiology; D003199:Computer Systems; D003627:Data Interpretation, Statistical; D005246:Feedback; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007858:Learning; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D009039:Motion Perception / Q000502:physiology; D009043:Motor Activity / Q000502:physiology; D010100:Oxygen / Q000097:blood; D012044:Regression Analysis; D015203:Reproducibility of Results; D013028:Space Perception / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen