Yuzhuo Su, Thomas Radman, Jake Vaynshteyn, Lucas C. Parra, Marom Bikson
Purpose: To determine the effects of high-frequency electrical stimulation on electrographic seizure activity during and after stimulation (ON-effect and OFF-effect). Methods: The modulation and...
Modulation of carbachol-evoked gamma activity in vitro with low-amplitude AC electric fields (2009)
Davide Reato, Marom Bikson, Lucas C. Parra
Oscillations of field potentials at gamma frequencies (30-80 Hz) are normally present in the brain. Applied oscillatory electric fields that are comparable in magnitude to endogenous fields have been...
Decoding of Brain State (2009)
Lucas C. Parra, Christoforos Christoforou, Adam D. Gerson, Mads Dyrholm, An Luo, Mark Wagner, ...
[Application to performance augmentation in high-throughput tasks] The conventional goal for a brain-computer interface has been to restore, for paralyzed individuals, a seamless interaction with the...
Adaptive Template Matching with Shift-Invariant Semi-NMF (2009)
Jonathan Le Roux, Alain De Cheveigné, Lucas C. Parra
How does one extract unknown but stereotypical events that are linearly superimposed within a signal with variable latencies and variable amplitudes? One could think of using template matching or...
* These authors contributed equally to this work. (2009)
Wei Ji Ma, Xiang Zhou, Lars A. Ross, John J. Foxe, Lucas C. Parra, Wei Ji Ma
effectiveness Watching a speaker’s facial movements can dramatically enhance our ability to comprehend words, especially in noisy environments. From a general doctrine of combining information from...
Adaptive Template Matching with Shift-Invariant Semi-NMF (2009)
Jonathan Le Roux, Alain De Cheveigné, Lucas C. Parra
How does one extract unknown but stereotypical events that are linearly superimposed within a signal with variable latencies and variable amplitudes? One could think of using template matching or...
Second Order Bilinear Discriminant Analysis for single-trial EEG analysis (2009)
Christoforos Christoforou, Paul Sajda, Lucas C. Parra
Traditional analysis methods for single-trial classification of electroencephalography (EEG) focus on two types of paradigms: phase locked methods, in which the amplitude of the signal is used as the...
Small fields change spike timing: A functional role of local-field potentials? (2008)
Yuzhuo Su, Thomas Radman, Marom Bikson, Lucas C. Parra
Small electric fields will polarize neurons by only a small amount; for this reason small electric fields have previously been suggested to have no physiologically relevant effects. However, in...
Mads Dyrholm, Christoforos Christoforou, Lucas C. Parra, Pack Kaelbling
Factor analysis and discriminant analysis are often used as complementary approaches to identify linear components in two dimensional data arrays. For three dimensional arrays, which may organize...
Thomas Radman, Yuzhuo Su, Je Hi An, Lucas C. Parra, Marom Bikson
Despite compelling phenomenological evidence that small electric fields (<5 mV/mm) can affect brain function, a quantitative and experimentally verified theory is currently lacking. Here we...
Lucas C. Parra, Senior Member, Christoforos Christoforou, Adam D. Gerson, Mads Dyrholm, An Luo, ...
Spatio-temporal linear decoding of brain state:
Small fields change spike timing: A functional role of local-field potentials? (2008)
Yuzhuo Su, Thomas Radman, Marom Bikson, Lucas C. Parra
Small electric fields will polarize neurons by only a small amount; for this reason small electric fields have previously been suggested to have no physiologically relevant effects. However, in...
Michael Syskind Pedersen, Jan Larsen, Ulrik Kjems, Lucas C. Parra
In this chapter, we provide an overview of existing algorithms for blind source separation of convolutive audio mixtures. We provide a taxonomy, wherein many of the existing algorithms can be...
Barak A. Pearlmutter, Lucas C. Parra
In the square linear blind source separation problem, one must nd a linear unmixing operator which can detangle the result xi(t) of mixing n unknown independent sources si(t) through an unknown n n...
Maximising Sensitivity in a Spiking Network (2008)
Anthony Bell Redwood, Anthony J. Bell, Lucas C. Parra
We use unsupervised probabilistic machine learning ideas to try to explain the kinds of learning observed in real neurons, the goal being to connect abstract principles of self-organisation to known...
Single-trial analysis of EEG during rapid visual discrimination: Enabling cortically-coupled (2008)
Computer Vision Paul, Paul Sajda, Adam D. Gerson, Marios G. Philiastides, Lucas C. Parra
We describe our work using linear discrimination of multi-channel electroencephalography for single-trial detection of neural signatures of visual recognition events. We demonstrate the approach as a...
Parra, Lucas C., Christoforou, Christoforos, Gerson, Adam D., Dyrholm, Mads, Luo, An, Wagner, Mark, ...
Improved Human-Machine Performance Using Real-Time EEG Monitoring (2007)
Lucas C. Parra, Clay D. Spence, Adam D. Gerson, Paul Sajda
Abstract--We describe a brain computer interface (BCI) system, which uses a set of adaptive linear preprocessing and classification algorithms for single-trial detection of Er-ror Pelated Negativity...
Illusory Percepts from Auditory Adaptation (2007)
Parra, Lucas C., Pearlmutter, Barak A.
Phenomena resembling tinnitus and Zwicker phantom tone are seen to result from an auditory gain adaptation mechanism that attempts to make full use of a fixed-capacity channel. In the case of...
A Survey of Convolutive Blind Source Separation Methods (2007)
Pedersen, Michael Syskind, Larsen, Jan, Kjems, Ulrik, Parra, Lucas C.
In this chapter, we provide an overview of existing algorithms for blind source separation of convolutive audio mixtures. We provide a taxonomy, wherein many of the existing algorithms can be...
Bilinear discriminant component analysis (2007)
Mads Dyrholm, Christoforos Christoforou, Lucas C. Parra, Pack Kaelbling
Factor analysis and discriminant analysis are often used as complementary approaches to identify linear components in two dimensional data arrays. For three dimensional arrays, which may organize...
Recipes for the linear analysis of EEG (2005)
Lucas Parra Clay, Lucas C. Parra, Clay D. Spence, Paul Sajda C
this paper, we describe a simple set of "recipes" for the analysis of high spatial density EEG. We focus on a linear integration of multiple channels for extracting individual components...
Chemical Shift Imaging, Paul Sajda, Shuyan Du, Truman R. Brown, Radka Stoyanova, Dikoma C. Shungu, ...
We present an algorithm for blindly recovering constituent source spectra from magnetic resonance (MR) chemical shift imaging (CSI) of the human brain. The algorithm, which we call constrained...
Model of the Effect of Extracellular Fields on Spike Time Coherence (2004)
Accurate spike timing is emerging as an important comcept in the encoding of sensory stimuli. Accurately timed spiking has been recorded in-vivo in the visual and auditory cortex, many layers removed...
Lucas C. Parra, Clay D. Spence, Adam D. Gerson, Paul Sajda
Abstract—We describe a brain–computer interface (BCI) system, which uses a set of adaptive linear preprocessing and classification algorithms for single-trial detection of error related...
Geometric source separation: Merging convolutive source separation with geometric beamforming (2002)
Lucas C. Parra, Christopher V. Alvino
Abstract | Convolutive blind source separation and adaptive beamforming have a similar goal|extracting a source of interest (or multiple sources) while reducing undesired interferences. A benet of...
Geometric Source Separation: Merging Convolutive Source Separation with Geometric Beamforming (2002)
Lucas C. Parra, Christopher V. Alvino
Convolutive blind source separation and adaptive beamforming have a similar goal---extracting a source of interest (or multiple sources) while reducing undesired interferences. A benefit of source...
Separation of Non-Stationary Natural Signals (2001)
Lucas C. Parra, Clay D. Spence, Sarno Corporation, Sarno Corporation
Most approaches to the problem of source separation use the assumption of statistical independence. To capture statistical independence higher order statistics are required. In this chapter we will...
Reconstruction of cone-beam projections from Compton scattered data (2000)
The problem of reconstructing a 3D source distribution from Compton scattered data can be separated into two tasks. First, the angular distribution of line projections at different observation points...
Reconstruction of cone-beam projections from Compton scattered data (2000)
Lucas Parra Sarnoff, Lucas C. Parra
The problem of reconstructing a 3D source distribution from Compton scattered data can be separated into two tasks. First, the angular distribution of line projections at different observation points...
Temporal models in blind source separation (1998)
Independent component analysis (ICA) aims to nd statistical independent signals in an instantaneous linear mix. No knowledge of the original sources is
Maximum likelihood blind source separation: A context-sensitive generalization of ICA (1997)
Barak A. Pearlmutter, Lucas C. Parra
In the square linear blind source separation problem, one must find a linear unmixing operator which can detangle the result x i (t) of mixing n unknown independent sources s i (t) through an unknown...
Convolutive Source Separation and Signal Modeling with ML (1997)
Lucas C. Parra, Clay Spence, Bert De Vries
In independent component analysis (ICA) an instantaneous mix of sources can be recovered using maximum Likelihood (ML). In Convolutive blind source separation (BSS) the mixture arises as a...
Convolutive source separation and signal modeling with (1997)
Lucas C. Parra, Clay Spence, Bert De Vries
In independent component analysis (ICA) an instantaneous mix of sources can be recovered using maximum Likelihood (ML). In Convolutive blind source separation (BSS) the mixture arises as a...
Symplectic nonlinear component analysis (1996)
Statistically independent features can be extracted by nding a factorial representation of a signal distribution. Principal Component Analysis (PCA) accomplishes this for linear correlated and...
2914 J. Opt. Soc. Am. A/Vol. 14, No. 11/November 1997 Barrett et al. List-mode likelihood (1996)
Harrison H. Barrett, Timothy White, Lucas C. Parra
As photon-counting imaging systems become more complex, there is a trend toward measuring more attributes of each individual event. In various imaging systems the attributes can include several...
Ma, Wei Ji, Zhou, Xiang, Ross, Lars A., Foxe, John J., Parra, Lucas C.
Watching a speaker's facial movements can dramatically enhance our ability to comprehend words, especially in noisy environments. From a general doctrine of combining information from different...