Name
Title | ||
|---|---|---|
Signal quality and Bayesian signal processing in neurofeedback based on real-time fMRI. |
Abstract | ||
|---|---|---|
Real-time fMRI allows analysis and visualization of the brain activity online, i.e. within one repetition time. It can be used in neurofeedback applications where subjects attempt to control an activation level in a specified region of interest (ROI) of their brain. The signal derived from the ROI is contaminated with noise and artifacts, namely with physiological noise from breathing and heart beat, scanner drift, motion-related artifacts and measurement noise. We developed a Bayesian approach to reduce noise and to remove artifacts in real-time using a modified Kalman filter. The system performs several signal processing operations: subtraction of constant and low-frequency signal components, spike removal and signal smoothing. Quantitative feedback signal quality analysis was used to estimate the quality of the neurofeedback time series and performance of the applied signal processing on different ROIs. The signal-to-noise ratio (SNR) across the entire time series and the group event-related SNR (eSNR) were significantly higher for the processed time series in comparison to the raw data. Applied signal processing improved the t-statistic increasing the significance of blood oxygen level-dependent (BOLD) signal changes. Accordingly, the contrast-to-noise ratio (CNR) of the feedback time series was improved as well. In addition, the data revealed increase of localized self-control across feedback sessions. |
Year | DOI | Venue |
|---|---|---|
2012 | 10.1016/j.neuroimage.2011.07.076 | NeuroImage |
Keywords | Field | DocType |
Real-time fMRI,Neurofeedback,Signal processing,Bayesian,Kalman filter,Signal quality | Signal processing,Computer vision,Computer science,Kalman filter,Smoothing,Artificial intelligence,Region of interest,Communication noise,Signal averaging,Subtraction,Neurofeedback | Journal |
Volume | Issue | ISSN |
59 | 1 | 1053-8119 |
Citations | PageRank | References |
6 | 0.54 | 17 |
Authors | ||
5 | ||
Name | Order | Citations | PageRank |
|---|---|---|---|
| Yury Koush | 1 | 38 | 4.31 |
| Mikhail Zvyagintsev | 2 | 14 | 3.62 |
| Miriam Dyck | 3 | 9 | 1.12 |
| Krystyna A Mathiak | 4 | 9 | 1.38 |
| Klaus Mathiak | 5 | 179 | 32.04 |