Analysis of ER-fMRI time series with modified mother wavelet

Investigating the shape and time to a peak, called the HR delay, of hemodynamic response (HR) gives a novel tool to analyze human brain function. We have previously proposed an analysis method for detecting activated areas and measuring HR delay simultaneously. We improve the performance of the method by modifying a mother wavelet. The modified mother wavelet is based on an HR function defined mathematically by the SPM (statistical parametric mapping) software by K.J. Friston et al. (see Human Brain Mapping, vol.2, p.189-210, 1995). To evaluate the proposed method, it and conventional methods are applied to phantom data and data from human subjects. The results indicate that the proposed method could detect activated areas equivalent to those found by conventional methods, and more accurately.