Monica-Claudia Serban - Academia.edu (original) (raw)

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Papers by Monica-Claudia Serban

International Symposium on Signals, Circuits and Systems, 2005. ISSCS 2005.

In this paper we investigate the performance of using, within the EEG classification algorithm, f... more In this paper we investigate the performance of using, within the EEG classification algorithm, feature extractors such phase synchrony and relative power spectral density indices calculated for seven frequency bands-delta (0.1-4 Hz), theta (4-7 Hz), alpha1 (7-10 Hz), alpha2 (10-13 Hz), beta1 (13-18 Hz), beta2 (18-30 Hz), gamma (30-70 Hz)-, that are believed to mostly reflect functionally different components of cognitive cortical activity. For classification of five mental tasks (baseline, count, letter, math and rotate) a Multi Layer Perceptron (MLP) neural network classifier was used. A standard principal component analysis (PCA) was applied here in order to reduce the high dimensionality of the input data. To quantitatively assess the performance of the extracted features a comparative study between their corresponding results and between them and some other EEG features is also provided. I.

2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006

In order to analyze the activation pattern of the two putative central tremor oscillators that in... more In order to analyze the activation pattern of the two putative central tremor oscillators that independently control the right and left hands, two hemifield repetitive visual stimulation tests were employed. The dynamical evolution of the tremor spectral characteristics of both hands was tracked using coherence joint time-frequency analysis. To get reliable spectral estimators for the tremor stochastic process, two non-parametric methods were applied: a Welch periodogram-based method and a multitaper method. In both cases, the results were the same: none significant coherence value could indicate a potential central driving activity.

Studies in health technology and informatics, 2005

This paper focuses on the tremor signal as a window to observe and analyze the central nervous sy... more This paper focuses on the tremor signal as a window to observe and analyze the central nervous system's functions and organization. In this idea it is proposed a custom system and some methodologies that reveal the cross-modalities influences, specifically, the increased complexity of the neuro-motor system generating the tremor as a result of photic driving activation method. The correlation dimension is used as a measure of system's complexity change and the behaviour of the physiological system is modelled using the Hindmarsh-Rose neuronal model. The proposed system includes: three neurons and their unidirectional coupling - considered to be a possible way the system changes its complexity -, the dynamical noise and the photic driving action. The correlation dimension (CD) analysis was performed on the real tremor signal and on the output signal of the modelled system. The global behaviour of the CD parameter proved to be similar in both cases. Thus, the results are promo...

2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006

In order to analyze the activation pattern of the two putative central tremor oscillators that in... more In order to analyze the activation pattern of the two putative central tremor oscillators that independently control the right and left hands, two hemifield repetitive visual stimulation tests were employed. The dynamical evolution of the tremor spectral characteristics of both hands was tracked using coherence joint time-frequency analysis. To get reliable spectral estimators for the tremor stochastic process, two nonparametric methods were applied: a Welch periodogram-based method and a multitaper method. In both cases, the results were the same: none significant coherence value could indicate a potential central driving activity.

Physiological tremor is a complex signal resulting from interactions between several mechanical a... more Physiological tremor is a complex signal resulting from interactions between several mechanical and neural factors. In this paper we bring into discussion only the neurogenic components that, first, have been mainly attributed to spinal interneuronal systems or subcortical oscillators but more recently, also to cortical rhythms. Here we investigated, using visual stimuli at different frequencies (5Hz, 10Hz, 15Hz), whether the

International Symposium on Signals, Circuits and Systems, 2005

International Symposium on Signals, Circuits and Systems, 2005. ISSCS 2005.

2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006

Studies in health technology and informatics, 2005

2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006

In order to analyze the activation pattern of the two putative central tremor oscillators that in... more In order to analyze the activation pattern of the two putative central tremor oscillators that independently control the right and left hands, two hemifield repetitive visual stimulation tests were employed. The dynamical evolution of the tremor spectral characteristics of both hands was tracked using coherence joint time-frequency analysis. To get reliable spectral estimators for the tremor stochastic process, two nonparametric methods were applied: a Welch periodogram-based method and a multitaper method. In both cases, the results were the same: none significant coherence value could indicate a potential central driving activity.

International Symposium on Signals, Circuits and Systems, 2005