Timothy P. L. Roberts

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The human motor cortex exhibits characteristic beta (15-30 Hz) and gamma oscillations (60-90 Hz), typically observed in the context of transient finger movement tasks. The functional significance of these oscillations, such as post-movement beta rebound (PMBR) and movement-related gamma synchrony (MRGS) remains unclear. Considerable animal and human(More)
BACKGROUND Difficulty modeling complex behavioral phenotypes in rodents (e.g., language) has hindered pathophysiological investigation and treatment development for autism spectrum disorders. Recent human neuroimaging studies, however, have identified functional biomarkers that can be more directly related to the abnormal neural dynamics of autism spectrum(More)
Motivated by auditory and speech deficits in autism spectrum disorders (ASD), the frequency dependence of superior temporal gyrus (STG) 50 msec (M50) and 100 msec (M100) neuromagnetic auditory evoked field responses in children with ASD and typically developing controls were evaluated. Whole-cortex magnetoencephalography (MEG) was obtained from 17 typically(More)
Left hemisphere dominance represents the typical language lateralization profile for the majority of neurologically healthy, right-handed individuals. We investigated hemispheric dominance for language in language-impaired children with autism and typically developing controls to investigate the hypothesis that atypical functional specialization for(More)
(1)H magnetic resonance spectroscopy ((1)H MRS) and spectral editing methods, such as MEGA-PRESS, allow researchers to investigate metabolite and neurotransmitter concentrations in-vivo. Here we address the utilization of (1)H MRS for the investigation of GABA concentrations in the ASD brain, in three locations; motor, visual and auditory areas. An initial(More)
Deficient rapid temporal processing may contribute to impaired language development by interfering with the processing of brief acoustic transitions crucial for speech perception. Using magnetoencephalography, evoked neural activity (M50, M100) to two 40 ms tones passively presented in rapid succession was recorded in 10 neurologically normal adults and 40(More)
Structural magnetic resonance (MR) connectomics holds promise for the diagnosis, outcome prediction, and treatment monitoring of many common neurodevelopmental, psychiatric, and neurodegenerative disorders for which there is currently no clinical utility for MR imaging (MRI). Before computational network metrics from the human connectome can be applied in a(More)
Examination of resting state brain activity using electrophysiological measures like complexity as well as functional connectivity is of growing interest in the study of autism spectrum disorders (ASD). The present paper jointly examined complexity and connectivity to obtain a more detailed characterization of resting state brain activity in ASD.(More)
PURPOSE To evaluate the diagnostic and prognostic potential of a new protein-binding contrast medium, B22956/1, for quantitatively characterizing tumor microvessels by MRI and monitoring response to antiangiogenic therapy. MATERIALS AND METHODS Dynamic contrast-enhanced MRI (DCE-MRI) was performed in an experimental cancer model with the use of the novel(More)
This paper presents a paradigm for generating a quantifiable marker of pathology that supports diagnosis and provides a potential biomarker of neuropsychiatric disorders, such as autism spectrum disorder (ASD). This is achieved by creating high-dimensional nonlinear pattern classifiers using support vector machines (SVM), that learn the underlying pattern(More)