Dataset Information

Unraveling nonlinear electrophysiologic processes in the human visual system with full dimension spectral analysis.

ABSTRACT: Natural sensory signals have nonlinear structures dynamically composed of the carrier frequencies and the variation of the amplitude (i.e., envelope). How the human brain processes the envelope information is still poorly understood, largely due to the conventional analysis failing to quantify it directly. Here, we used a recently developed method, Holo-Hilbert spectral analysis, and steady-state visually evoked potential collected using electroencephalography (EEG) recordings to investigate how the human visual system processes the envelope of amplitude-modulated signals, in this case with a 14?Hz carrier and a 2?Hz envelope. The EEG results demonstrated that in addition to the fundamental stimulus frequencies, 4?Hz amplitude modulation residing in 14?Hz carrier and a broad range of carrier frequencies covering from 8 to 32?Hz modulated by 2?Hz amplitude modulation are also found in the two-dimensional frequency spectrum, which have not yet been recognized before. The envelope of the stimulus is also found to dominantly modulate the response to the incoming signal. The findings thus reveal that the electrophysiological response to amplitude-modulated stimuli is more complex than could be revealed by, for example, Fourier analysis. This highlights the dynamics of neural processes in the visual system.

SUBMITTER: Nguyen KT

PROVIDER: S-EPMC6858326 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Unraveling nonlinear electrophysiologic processes in the human visual system with full dimension spectral analysis.

Nguyen Kien Trong KT Liang Wei-Kuang WK Lee Victor V Chang Wen-Sheng WS Muggleton Neil G NG Yeh Jia-Rong JR Huang Norden E NE Juan Chi-Hung CH

Scientific reports 20191115 1

Natural sensory signals have nonlinear structures dynamically composed of the carrier frequencies and the variation of the amplitude (i.e., envelope). How the human brain processes the envelope information is still poorly understood, largely due to the conventional analysis failing to quantify it directly. Here, we used a recently developed method, Holo-Hilbert spectral analysis, and steady-state visually evoked potential collected using electroencephalography (EEG) recordings to investigate how ...[more]

PMID: 31729410

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Unraveling nonlinear electrophysiologic processes in the human visual system with full dimension spectral analysis.

Publications

Unraveling nonlinear electrophysiologic processes in the human visual system with full dimension spectral analysis.

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