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The goal of this article is to model multi-subject task-induced fMRI response among predefined regions of interest (ROIs) of the human brain. Conventional approaches to fMRI analysis only take into account temporal correlations, but do not rigorously model the underlying spatial correlation due to the complexity of estimating and inverting the high dimensional spatio-temporal covariance matrix. Other spatio-temporal model approaches estimate the covariance matrix with the assumption of stationary time series, which is not always feasible. To address these limitations, we propose a double-wavelet approach for modeling the spatio-temporal brain process. Working with wavelet coefficients simplifies temporal and spatial covariance structure because under regularity conditions, wavelet coefficients are approximately uncorrelated. Different wavelet functions were used to capture different correlation structures in the spatio-temporal model. The main advantages of the wavelet approach are that it is scalable and that it deals with non-stationarity in brain signals. Simulation studies showed that our method could reduce false positive and false negative rates by taking into account spatial and temporal correlations simultaneously. We also applied our method to fMRI data to study activation in pre-specified ROIs in the prefontal cortex. Data analysis showed that the result using the double-wavelet approach was more consistent than the conventional approach when sample size decreased. This article is protected by copyright. All rights reserved.
This article was published in the following journal.
Functional near-infrared spectroscopy (fNIRS) is a fast-developing non-invasive functional brain imaging technology widely used in cognitive neuroscience, clinical research and neural engineering. How...
Higher harmonics have been widely used to characterize nanomechanical properties of the sample surface in tapping mode atomic force microscopy. They are usually analyzed by the Fourier transform metho...
Event-related mental task information collected from electroencephalography (EEG) signals, which are functionally related to different brain areas, possesses complex and non-stationary signal features...
The statistical properties of the noise in the Mie lidar signal are analyzed by the statistical hypotheses testing method. Based on this, an adaptive filter is proposed to eliminate the noise. The lea...
Objective: Breast Cancer is the most invasive disease and fatal disease next to lung cancer in human. Early detection of breast cancer is accomplished by X-ray mammography. Mammography is the most eff...
Several methods exist to evaluate motor function in the child with cerebral palsy and are used to assess the outcome of a clinical intervention. However, these scales are not directed towa...
People with stroke experience weakness and incoordination. Studies have shown that with functional task practice, people can increase motor control and strength to a certain extent. This s...
This study will locate areas in the brain that help people devise action plans to carry out complex tasks requiring use of strategy. The ability to plan strategically is impaired in patien...
Recently, we have shown functional resonance imaging (fMRI) that variations in signal induced by a language task were significantly lower in a semantic region of the left hemisphere (compr...
Using a within‐subject cross‐over design, we will include 20 patients with Parkinson disease (PD) and peak‐of‐dose dyskinesia. Patients will be studied after withdrawal from their...
Signal and data processing method that uses decomposition of wavelets to approximate, estimate, or compress signals with finite time and frequency domains. It represents a signal or data in terms of a fast decaying wavelet series from the original prototype wavelet, called the mother wavelet. This mathematical algorithm has been adopted widely in biomedical disciplines for data and signal processing in noise removal and audio/image compression (e.g., EEG and MRI).
The observation and analysis of movements in a task with an emphasis on the amount of time required to perform the task.
The functional superiority and preferential use of one eye over the other. The term is usually applied to superiority in sighting (VISUAL PERCEPTION) or motor task but not difference in VISUAL ACUITY or dysfunction of one of the eyes. Ocular dominance can be modified by visual input and NEUROTROPHIC FACTORS.
An assessment of HEALTH STATUS requested by third parties (e.g. insurers, adjudicating bodies, law enforcement, attorneys, etc) on a subject’s functional ability. Such information may be used in optimizing treatment or making informed decisions on compensation.
A multi-functional catenin that participates in CELL ADHESION and nuclear signaling. Beta catenin binds CADHERINS and helps link their cytoplasmic tails to the ACTIN in the CYTOSKELETON via ALPHA CATENIN. It also serves as a transcriptional co-activator and downstream component of WNT PROTEIN-mediated SIGNAL TRANSDUCTION PATHWAYS.