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Multiple linear regression to estimate time-frequency electrophysiological responses in single trials.

Hu L, Zhang ZG, Mouraux A, Iannetti GD - Neuroimage (2015)

Bottom Line: Transient sensory, motor or cognitive event elicit not only phase-locked event-related potentials (ERPs) in the ongoing electroencephalogram (EEG), but also induce non-phase-locked modulations of ongoing EEG oscillations.ERD and ERS reflect changes in the parameters that control oscillations in neuronal networks and, depending on the frequency at which they occur, represent neuronal mechanisms involved in cortical activation, inhibition and binding.This permits within-subject statistical comparisons, correlation with pre-stimulus features, and integration of simultaneously-recorded EEG and fMRI.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Cognition and Personality (Ministry of Education) and Faculty of Psychology, Southwest University, Chongqing, China; Department of Neuroscience, Physiology and Pharmacology, University College London, UK. Electronic address: huli@swu.edu.cn.

No MeSH data available.


Related in: MedlinePlus

Time-frequency feature isolation using PCA decomposition with Varimax rotation.Left: Group-level TFDs of laser-elicited responses at electrode Cz. x-axis: latency (s); y-axis: frequency (Hz). Both TFDs (top: Magnitude; bottom: PLV) were averaged across all single-trial TFDs of all subjects, after subtracting the baseline. As compared to the baseline, significant differences in PLVs are outlined in white (bootstrapping test with FDR correction), which indicate that only the ERP response was phase-locked to stimulus onset, while the other TFD responses were not. Middle: The eigenvalue plot shows the variance explained by the first 30 extracted PCs. The first three PCs explained the largest amount of variance in the data (23.1%, 9.2% and 5.9%, corresponding to ERP, ERD and ERS responses), while the explained variance for any of the remaining PCs was less than 5%. Right: The first three PCs correspond to the ERP, ERD and ERS in the time-frequency plane, respectively. The thresholded TFDs were obtained by applying a two-SD cut-off. The amount of background EEG noise was remarkably reduced, while the regions corresponding to ERP/ERS/ERD responses were clearly preserved. The ERP region was located at 50–550 ms post-stimulus (in time) and 3–10 Hz (in frequency); the ERD region at 50–1000 ms and 9–12 Hz; the ERS region at 217–447 ms and 10–19 Hz in frequency.
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f0005: Time-frequency feature isolation using PCA decomposition with Varimax rotation.Left: Group-level TFDs of laser-elicited responses at electrode Cz. x-axis: latency (s); y-axis: frequency (Hz). Both TFDs (top: Magnitude; bottom: PLV) were averaged across all single-trial TFDs of all subjects, after subtracting the baseline. As compared to the baseline, significant differences in PLVs are outlined in white (bootstrapping test with FDR correction), which indicate that only the ERP response was phase-locked to stimulus onset, while the other TFD responses were not. Middle: The eigenvalue plot shows the variance explained by the first 30 extracted PCs. The first three PCs explained the largest amount of variance in the data (23.1%, 9.2% and 5.9%, corresponding to ERP, ERD and ERS responses), while the explained variance for any of the remaining PCs was less than 5%. Right: The first three PCs correspond to the ERP, ERD and ERS in the time-frequency plane, respectively. The thresholded TFDs were obtained by applying a two-SD cut-off. The amount of background EEG noise was remarkably reduced, while the regions corresponding to ERP/ERS/ERD responses were clearly preserved. The ERP region was located at 50–550 ms post-stimulus (in time) and 3–10 Hz (in frequency); the ERD region at 50–1000 ms and 9–12 Hz; the ERS region at 217–447 ms and 10–19 Hz in frequency.

Mentions: In order to separate physiologically relevant TF-features (i.e., ERP, ERD, and ERS) within the TFDs of single-trial laser-evoked EEG responses measured from Cz-nose, we performed a PCA decomposition with Varimax rotation (Bernat et al., 2005; Dien, 2010; Kayser and Tenke, 2003), as successfully implemented in several recent studies (Bernat et al., 2007; Bernat et al., 2005; Mayhew et al., 2010). This approach allows the separation of physiologically distinct EEG activities that are contained in the time-frequency plane. The procedure of PCA with Varimax rotation consists in the following five steps (summarized in Fig. 1) (Bernat et al., 2005; Mayhew et al., 2010).(1)


Multiple linear regression to estimate time-frequency electrophysiological responses in single trials.

Hu L, Zhang ZG, Mouraux A, Iannetti GD - Neuroimage (2015)

Time-frequency feature isolation using PCA decomposition with Varimax rotation.Left: Group-level TFDs of laser-elicited responses at electrode Cz. x-axis: latency (s); y-axis: frequency (Hz). Both TFDs (top: Magnitude; bottom: PLV) were averaged across all single-trial TFDs of all subjects, after subtracting the baseline. As compared to the baseline, significant differences in PLVs are outlined in white (bootstrapping test with FDR correction), which indicate that only the ERP response was phase-locked to stimulus onset, while the other TFD responses were not. Middle: The eigenvalue plot shows the variance explained by the first 30 extracted PCs. The first three PCs explained the largest amount of variance in the data (23.1%, 9.2% and 5.9%, corresponding to ERP, ERD and ERS responses), while the explained variance for any of the remaining PCs was less than 5%. Right: The first three PCs correspond to the ERP, ERD and ERS in the time-frequency plane, respectively. The thresholded TFDs were obtained by applying a two-SD cut-off. The amount of background EEG noise was remarkably reduced, while the regions corresponding to ERP/ERS/ERD responses were clearly preserved. The ERP region was located at 50–550 ms post-stimulus (in time) and 3–10 Hz (in frequency); the ERD region at 50–1000 ms and 9–12 Hz; the ERS region at 217–447 ms and 10–19 Hz in frequency.
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Related In: Results  -  Collection

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f0005: Time-frequency feature isolation using PCA decomposition with Varimax rotation.Left: Group-level TFDs of laser-elicited responses at electrode Cz. x-axis: latency (s); y-axis: frequency (Hz). Both TFDs (top: Magnitude; bottom: PLV) were averaged across all single-trial TFDs of all subjects, after subtracting the baseline. As compared to the baseline, significant differences in PLVs are outlined in white (bootstrapping test with FDR correction), which indicate that only the ERP response was phase-locked to stimulus onset, while the other TFD responses were not. Middle: The eigenvalue plot shows the variance explained by the first 30 extracted PCs. The first three PCs explained the largest amount of variance in the data (23.1%, 9.2% and 5.9%, corresponding to ERP, ERD and ERS responses), while the explained variance for any of the remaining PCs was less than 5%. Right: The first three PCs correspond to the ERP, ERD and ERS in the time-frequency plane, respectively. The thresholded TFDs were obtained by applying a two-SD cut-off. The amount of background EEG noise was remarkably reduced, while the regions corresponding to ERP/ERS/ERD responses were clearly preserved. The ERP region was located at 50–550 ms post-stimulus (in time) and 3–10 Hz (in frequency); the ERD region at 50–1000 ms and 9–12 Hz; the ERS region at 217–447 ms and 10–19 Hz in frequency.
Mentions: In order to separate physiologically relevant TF-features (i.e., ERP, ERD, and ERS) within the TFDs of single-trial laser-evoked EEG responses measured from Cz-nose, we performed a PCA decomposition with Varimax rotation (Bernat et al., 2005; Dien, 2010; Kayser and Tenke, 2003), as successfully implemented in several recent studies (Bernat et al., 2007; Bernat et al., 2005; Mayhew et al., 2010). This approach allows the separation of physiologically distinct EEG activities that are contained in the time-frequency plane. The procedure of PCA with Varimax rotation consists in the following five steps (summarized in Fig. 1) (Bernat et al., 2005; Mayhew et al., 2010).(1)

Bottom Line: Transient sensory, motor or cognitive event elicit not only phase-locked event-related potentials (ERPs) in the ongoing electroencephalogram (EEG), but also induce non-phase-locked modulations of ongoing EEG oscillations.ERD and ERS reflect changes in the parameters that control oscillations in neuronal networks and, depending on the frequency at which they occur, represent neuronal mechanisms involved in cortical activation, inhibition and binding.This permits within-subject statistical comparisons, correlation with pre-stimulus features, and integration of simultaneously-recorded EEG and fMRI.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Cognition and Personality (Ministry of Education) and Faculty of Psychology, Southwest University, Chongqing, China; Department of Neuroscience, Physiology and Pharmacology, University College London, UK. Electronic address: huli@swu.edu.cn.

No MeSH data available.


Related in: MedlinePlus