Longitudinal Sleep EEG Power Spectral Analysis Studies in Adolescents with Minor Head Injury

Fractals are self-similar patterns that repeat at different scales, the complexity of which are expressed as a fractional Euclidean dimension D between 0 (a point) and 2 (a filled plane). The drip paintings of American painter Jackson Pollock (JP) are fractal in nature, and Pollock’s most illustrious works are of the high-D (~1.7) category. This would imply that people prefer more complex fractal patterns, but some research has instead suggested people prefer lower-D fractals. Furthermore, research has suggested that parietal and frontal brain activity tracks the complexity of fractal patterns, but previous research has artificially binned fractals depending on fractal dimension, rather than treating fractal dimension as a parametrically varying value. We used white layers extracted from JP artwork as stimuli, and constructed statistically matched 2-dimensional random Cantor sets as control stimuli. We recorded the electroencephalogram (EEG) while participants viewed the JP and matched random Cantor fractal patterns. Participants then rated their subjective preference for each pattern. We used a single-trial analysis to construct within-subject models relating subjective preference to fractal dimension D, as well as relating D and subjective preference to single-trial EEG power spectra. Results indicated that participants preferred higher-D images for both JP and Cantor stimuli. Power spectral analysis showed that, for artistic fractal images, parietal alpha and beta power parametrically tracked complexity of fractal patterns, while for matched mathematical fractals, parietal power tracked complexity of patterns over a range of frequencies, but most prominently in alpha band. Furthermore, parietal alpha power parametrically tracked aesthetic preference for both artistic and matched Cantor patterns. Overall, our results suggest that perception of complexity for artistic and computer-generated fractal images is reflected in parietal-occipital alpha and beta activity, and neural substrates of preference for complex stimuli are reflected in parietal alpha band activity.

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A comparison of period amplitude and power spectral analysis of sleep EEG in normal adults and depressed outpatients

Psychiatry Research ◽

10.1016/0165-1781(95)02615-4 ◽

1995 ◽

Vol 56 (3) ◽

pp. 245-256 ◽

Cited By ~ 16

Author(s):

Roseanne Armitage ◽

Robert Hoffmann ◽

Thomas Fitch ◽

Christine Morel ◽

Richard Bonato

Keyword(s):

Spectral Analysis ◽

Power Spectral Analysis ◽

Sleep Eeg ◽

Power Spectral ◽

Normal Adults

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Assessing traumatic brain injuries using EEG power spectral analysis and instantaneous phase

2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society ◽

10.1109/embc.2012.6347014 ◽

2012 ◽

Cited By ~ 2

Author(s):

A. Napoli ◽

M. Barbe ◽

K. Darvish ◽

I. Obeid

Keyword(s):

Spectral Analysis ◽

Brain Injuries ◽

Power Spectral Analysis ◽

Traumatic Brain Injuries ◽

Instantaneous Phase ◽

Power Spectral ◽

Eeg Power

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EEG Power Spectral Analysis of Abnormal Cortical Activations During REM/NREM Sleep in Obstructive Sleep Apnea

Frontiers in Neurology ◽

10.3389/fneur.2021.643855 ◽

2021 ◽

Vol 12 ◽

Author(s):

Shuling Liu ◽

Jiucheng Shen ◽

Yezhou Li ◽

Jing Wang ◽

Jianhua Wang ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Spectral Analysis ◽

Power Spectral Analysis ◽

Nrem Sleep ◽

The Other ◽

Frequency Bands ◽

Delta Band ◽

Power Spectral ◽

Obstructive Sleep ◽

Eeg Power

Objective: To characterize electroencephalogram (EEG) power in different frequency bands during rapid eye movement (REM) sleep and non-rapid eye movement (NREM) sleep in patients with obstructive sleep apnea (OSA).Methods: Retrospective data on 151 patients were collected and divided into three groups: primary snoring group (AHI < 5/h), mild-moderate OSA group (6 ≤ AHI < 30/h), and severe OSA group (AHI ≥ 30/h). EEG recordings in the frontal, central, and occipital regions were extracted from both REM and NREM sleep, to compute the normalized spectral power densities in the delta, theta, alpha, sigma, beta, and gamma frequency bands, using Fast Fourier Transform. Correlations between the computed EEG power and PSG parameters were analyzed.Results: In NREM sleep, elevated normalized power spectral density (PSD) in the delta band was observed in the severe OSA group compared to the other two groups. In contrast, the PSD of the other frequency bands showed a corresponding decrease in the severe OSA group. In REM sleep, similar changes were observed in the frontal region. Delta band PSD was positively correlated with Apnea Hypopnea Index (AHI) (r = 0.33), longest time of apnea, oxygen desaturation index (ODI) (r = 0.34), percent sleep time below 90% SaO2 (T90%) (r = 0.30), Arousal Index (ArI) (r = 0.29), and negatively correlated with N3%, minimum oxygen saturation (minSaO2).Conclusion: Our findings provide neurophysiological evidence for pathological cortical activation during REM/NREM sleep, which may be associated with the arousals and cognitive impairments in OSA. The technique of power spectral analysis could prove a potentially useful tool in complementing traditional PSG parameters in assessing disease burden to guide therapeutic decisions.

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