Affiliation: University College London
- Transcranial electrical brain stimulation modulates neuronal tuning curves in perception of numerosity and durationAmir Homayoun Javadi
Institute of Behavioural Neuroscience, Department of Experimental Psychology, University College London, WC1H 0AP, London, UK Electronic address
Neuroimage 102:451-7. 2014..We believe that this approach may prove useful in understanding the impact of brain stimulation on other cognitive domains. ..
- A general Bayesian treatment for MEG source reconstruction incorporating lead field uncertaintyJ D Lopez
Mechatronics School, Bl M8 108 Facultad de Minas, Universidad Nacional de Colombia, Medellin, Colombia
Neuroimage 60:1194-204. 2012..We also show that this process gives improved posterior distributions on the estimated current distributions, and can be extended to make inference on the locations of local maxima by providing confidence intervals for each source...
- Bilinear dynamical systemsW Penny
Wellcome Department of Imaging Neuroscience, University College, London WC1N 3BG, UK
Philos Trans R Soc Lond B Biol Sci 360:983-93. 2005..We report preliminary results that focus on the assumed stochastic nature of the neurodynamic model and compare the method to Wiener deconvolution...
- Bayesian fMRI time series analysis with spatial priorsWilliam D Penny
Wellcome Department of Imaging Neuroscience, UCL, London, UK
Neuroimage 24:350-62. 2005..Our model generalizes earlier work on voxel-wise estimation of GLM-AR models and inference in GLMs using Posterior Probability Maps (PPMs). Results are shown on simulated data and on data from an event-related fMRI experiment...
- Mixtures of general linear models for functional neuroimagingWill Penny
Wellcome Department of Imaging Neuroscience, University College, 12 Queen Square, London WC1N 3BG, UK
IEEE Trans Med Imaging 22:504-14. 2003..The model can also be viewed as performing a spatio-temporal cluster analysis. The parameters of the model are estimated using an expectation maximization (EM) algorithm...
- Event-related brain dynamicsWill D Penny
Wellcome Department of Imaging Neuroscience, University College London, 12 Queen Square, London WC1N 3BG, UK
Trends Neurosci 25:387-9. 2002....
- Graph-partitioned spatial priors for functional magnetic resonance imagesL M Harrison
Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London, 12 Queen Square, London, WC1N 3BG UK
Neuroimage 43:694-707. 2008..The high-resolution fMRI data presented here had greatest evidence for the graph partitioned anisotropic model, which was best able to preserve fine functional detail...
- Dynamic causal modellingK J Friston
The Wellcome Department of Imaging Neuroscience, Institute of Neurology, Queen Square, London WC1N 3BG, UK
Neuroimage 19:1273-302. 2003..psychophysiologic interactions). However, unlike previous approaches in neuroimaging, the causal model ascribes responses to designed deterministic inputs, as opposed to treating inputs as unknown and stochastic...
- Diffusion-based spatial priors for imagingL M Harrison
The Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London, 12 Queen Square, London, WC1N 3BG, UK
Neuroimage 38:677-95. 2007..Critically, this means adaptive smoothing becomes an integral part of estimation and inference. We illustrate the method using synthetic and real fMRI data...
- Estimating the transfer function from neuronal activity to BOLD using simultaneous EEG-fMRIM J Rosa
Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, 12 Queen Square, WC1N 3BG, UK
Neuroimage 49:1496-509. 2010....
- Bayesian model selection maps for group studiesM J Rosa
Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, 12 Queen Square, London, UK
Neuroimage 49:217-24. 2010..This note describes the integration of the Bayesian mapping approach with a random effects analysis model for BMS using group data. We illustrate the method using fMRI data from a group of subjects performing a target detection task...
- Posterior probability maps and SPMsK J Friston
The Wellcome Department of Imaging Neuroscience, London, Queen Square, London WC1N 3BG, UK
Neuroimage 19:1240-9. 2003..We then compare Bayesian and classical inference through the equivalent PPMs and SPMs testing for the same effect in the same data...
- Post-hoc selection of dynamic causal modelsM J Rosa
Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London, 12 Queen Square, WC1N 3BG, UK
J Neurosci Methods 208:66-78. 2012....
- Diffusion-based spatial priors for functional magnetic resonance imagesL M Harrison
Wellcome Trust Centre for Neuroimaging, UCL, London, UK
Neuroimage 41:408-23. 2008..Indeed, for the auditory data we provide strong evidence for a non-stationary process, which concurs with a qualitative comparison of predicted activations at the boundary of functionally selective regions...
- Optimized beamforming for simultaneous MEG and intracranial local field potential recordings in deep brain stimulation patientsVladimir Litvak
UCL Institute of Neurology, Queen Square, WC1N 3BG, London, UK
Neuroimage 50:1578-88. 2010..Our findings demonstrate that physiologically meaningful information can be extracted from heavily contaminated MEG signals and pave the way for further analysis of combined MEG-LFP recordings in DBS patients...
- The known unknowns: neural representation of second-order uncertainty, and ambiguityDominik R Bach
Wellcome Trust Centre for Neuroimaging, University College London, London WC1N 3BG, United Kingdom
J Neurosci 31:4811-20. 2011..Our findings indicate that behavioral and neural responses to second-order uncertainty are distinct from those associated with ambiguity and may call for a reappraisal of previous data...
- Bayesian fMRI data analysis with sparse spatial basis function priorsGuillaume Flandin
Wellcome Department of Imaging Neuroscience, 12 Queen Square, London WC1N 3BG, UK
Neuroimage 34:1108-25. 2007..Results are shown on synthetic data and on data from an event-related fMRI experiment...
- MEG source localization under multiple constraints: an extended Bayesian frameworkJeremie Mattout
Wellcome Department of Imaging Neuroscience, 12 Queen Square, WC1N 3BG London, UK
Neuroimage 30:753-67. 2006..Finally, we show how model selection, using the log-evidence, can be used to select the best combination of priors. This enables a global strategy for multiple prior-based regularization of the MEG/EEG source reconstruction...
- Bayesian nonstationary autoregressive models for biomedical signal analysisMichael J Cassidy
Sobell Department of Neurophysiology, Institute of Neurology, University College London, UK
IEEE Trans Biomed Eng 49:1142-52. 2002..Results are presented on synthetic data and real electroencephalogram data recorded in event-related desynchronization and photic synchronization scenarios...
- Classical and Bayesian inference in neuroimaging: theoryK J Friston
The Wellcome Department of Imaging Neuroscience, The Gatsby Computational Neuroscience Unit, University College London, Queen Square, London, WC1N 3BG, United Kingdom
Neuroimage 16:465-83. 2002..Although diverse, all these estimation problems are accommodated by the PEB framework described in this paper...
- Temporal and spatial complexity measures for electroencephalogram based brain-computer interfacingS J Roberts
Department of Electrical and Electronic Engineering, Imperial College of Science, Technology and Medicine, London, UK
Med Biol Eng Comput 37:93-8. 1999..Results are shown on synthetic and real data sets...
- Conjunction revisitedKarl J Friston
The Wellcome Department of Imaging Neuroscience and Institute of Cognitive Neuroscience, University College London, 17 Queen Square, London, WC1N 3AR, UK
Neuroimage 25:661-7. 2005..This more general conjunction test is described...
- Bayesian M/EEG source reconstruction with spatio-temporal priorsNelson J Trujillo-Barreto
Brain Dynamics Department, Cuban Neuroscience Centre, P O Box 6412 6414, Ave 25, Esq 158, No 15202, Cubanacan, Playa, Havana, Cuba
Neuroimage 39:318-35. 2008..Finally, the VB-GLM approach is used to analyze an EEG data set from a face processing experiment...
- Modeling regional and psychophysiologic interactions in fMRI: the importance of hemodynamic deconvolutionDarren R Gitelman
The Northwestern Cognitive Brain Mapping Group, Cognitive Neurology and Alzheimer s Disease Center, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
Neuroimage 19:200-7. 2003..In this article, this assumption is revisited using estimates of underlying neuronal activity. These estimates use a parametric empirical Bayes formulation for hemodynamic deconvolution...