{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,7,1]],"date-time":"2024-07-01T15:17:38Z","timestamp":1719847058988},"reference-count":15,"publisher":"World Scientific Pub Co Pte Lt","issue":"02","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Neur. Syst."],"published-print":{"date-parts":[[2006,4]]},"abstract":"<jats:p> We present a new algorithm to estimate hemodynamic response function (HRF) and drift components of fMRI data in wavelet domain. The HRF is modeled by both parametric and nonparametric models. The functional Magnetic resonance Image (fMRI) noise is modeled as a fractional brownian motion (fBm). The HRF parameters are estimated in wavelet domain by exploiting the property that wavelet transforms with a sufficient number of vanishing moments decorrelates a fBm process. Using this property, the noise covariance matrix in wavelet domain can be assumed to be diagonal whose entries are estimated using the sample variance estimator at each scale. We study the influence of the sampling rate of fMRI time series and shape assumption of HRF on the estimation performance. Results are presented by adding synthetic HRFs on simulated and null fMRI data. We also compare these methods with an existing method,<jats:sup>1<\/jats:sup> where correlated fMRI noise is modeled by a second order polynomial functions. <\/jats:p>","DOI":"10.1142\/s012906570600055x","type":"journal-article","created":{"date-parts":[[2006,5,9]],"date-time":"2006-05-09T08:01:40Z","timestamp":1147161700000},"page":"125-138","source":"Crossref","is-referenced-by-count":6,"title":["WAVELET-BASED ESTIMATION OF HEMODYNAMIC RESPONSE FUNCTION FROM fMRI DATA"],"prefix":"10.1142","volume":"16","author":[{"given":"R.","family":"SRIKANTH","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, Indian Institute of Science, Bangalore, Karnataka 560012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A. G.","family":"RAMAKRISHNAN","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Indian Institute of Science, Bangalore, Karnataka 560012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"219","published-online":{"date-parts":[[2011,11,21]]},"reference":[{"key":"rf1","volume-title":"Bayesian Inference and Maximum Entropy Methods","author":"Marrelec G.","year":"2001"},{"key":"rf2","first-page":"4207","author":"Boyton G. M.","journal-title":"J. Neuroscience"},{"key":"rf3","first-page":"61","author":"Bullmore E.","journal-title":"Human Brain Mapping"},{"key":"rf4","doi-asserted-by":"publisher","DOI":"10.1109\/TMI.2003.809587"},{"key":"rf5","doi-asserted-by":"publisher","DOI":"10.1109\/42.832957"},{"key":"rf6","doi-asserted-by":"publisher","DOI":"10.1006\/nimg.1997.0263"},{"key":"rf7","volume-title":"Signal Processing with Fractals: A Wavelet-Based Approach","author":"Wornell G. W.","year":"1996"},{"key":"rf8","volume-title":"Statistics for Long-Memory Processes","author":"Beran J.","year":"1994"},{"key":"rf9","doi-asserted-by":"publisher","DOI":"10.1109\/18.119751"},{"key":"rf10","first-page":"1609","volume":"40","author":"Tewfik A. H.","journal-title":"IEEE Trans. Inform. Theory"},{"key":"rf11","doi-asserted-by":"publisher","DOI":"10.1109\/18.53745"},{"key":"rf12","doi-asserted-by":"publisher","DOI":"10.1109\/18.333875"},{"key":"rf13","volume-title":"Fundamentals of Statistical Signal Processing: Estimation Theory","author":"Kay S.","year":"1995"},{"key":"rf14","doi-asserted-by":"publisher","DOI":"10.1109\/18.650986"},{"key":"rf15","doi-asserted-by":"publisher","DOI":"10.1093\/biomet\/82.3.619"}],"container-title":["International Journal of Neural Systems"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.worldscientific.com\/doi\/pdf\/10.1142\/S012906570600055X","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,8,6]],"date-time":"2019-08-06T22:07:56Z","timestamp":1565129276000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.worldscientific.com\/doi\/abs\/10.1142\/S012906570600055X"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2006,4]]},"references-count":15,"journal-issue":{"issue":"02","published-online":{"date-parts":[[2011,11,21]]},"published-print":{"date-parts":[[2006,4]]}},"alternative-id":["10.1142\/S012906570600055X"],"URL":"https:\/\/doi.org\/10.1142\/s012906570600055x","relation":{},"ISSN":["0129-0657","1793-6462"],"issn-type":[{"value":"0129-0657","type":"print"},{"value":"1793-6462","type":"electronic"}],"subject":[],"published":{"date-parts":[[2006,4]]}}}