General spectral characteristics of human activity and its inherent scale-free fluctuations
Abstract The scale-free nature of daily human activity has been observed in different aspects; however, the description of its spectral characteristics is incomplete. General findings are complicated by the fact that—although actigraphy is commonly used in many research areas—the activity calculatio...
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2024-01-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-024-52905-8 |
| _version_ | 1797274875810807808 |
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| author | Bálint Maczák Zoltán Gingl Gergely Vadai |
| author_facet | Bálint Maczák Zoltán Gingl Gergely Vadai |
| author_sort | Bálint Maczák |
| collection | DOAJ |
| description | Abstract The scale-free nature of daily human activity has been observed in different aspects; however, the description of its spectral characteristics is incomplete. General findings are complicated by the fact that—although actigraphy is commonly used in many research areas—the activity calculation methods are not standardized; therefore, activity signals can be different. The presence of 1/f noise in activity or acceleration signals was mostly analysed for short time windows, and the complete spectral characteristic has only been examined in the case of certain types of them. To explore the general spectral nature of human activity in greater detail, we have performed Power Spectral Density (PSD) based examination and Detrended Fluctuation Analysis (DFA) on several-day-long, triaxial actigraphic acceleration signals of 42 healthy, free-living individuals. We generated different types of activity signals from these, using different acceleration preprocessing techniques and activity metrics. We revealed that the spectra of different types of activity signals generally follow a universal characteristic including 1/f noise over frequencies above the circadian rhythmicity. Moreover, we discovered that the PSD of the raw acceleration signal has the same characteristic. Our findings prove that the spectral scale-free nature is generally inherent to the motor activity of healthy, free-living humans, and is not limited to any particular activity calculation method. |
| first_indexed | 2024-03-07T15:04:25Z |
| format | Article |
| id | doaj.art-8448f46b9dcd469cb21384840817a243 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-03-07T15:04:25Z |
| publishDate | 2024-01-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-8448f46b9dcd469cb21384840817a2432024-03-05T18:57:46ZengNature PortfolioScientific Reports2045-23222024-01-0114111710.1038/s41598-024-52905-8General spectral characteristics of human activity and its inherent scale-free fluctuationsBálint Maczák0Zoltán Gingl1Gergely Vadai2Department of Technical Informatics, University of SzegedDepartment of Technical Informatics, University of SzegedDepartment of Technical Informatics, University of SzegedAbstract The scale-free nature of daily human activity has been observed in different aspects; however, the description of its spectral characteristics is incomplete. General findings are complicated by the fact that—although actigraphy is commonly used in many research areas—the activity calculation methods are not standardized; therefore, activity signals can be different. The presence of 1/f noise in activity or acceleration signals was mostly analysed for short time windows, and the complete spectral characteristic has only been examined in the case of certain types of them. To explore the general spectral nature of human activity in greater detail, we have performed Power Spectral Density (PSD) based examination and Detrended Fluctuation Analysis (DFA) on several-day-long, triaxial actigraphic acceleration signals of 42 healthy, free-living individuals. We generated different types of activity signals from these, using different acceleration preprocessing techniques and activity metrics. We revealed that the spectra of different types of activity signals generally follow a universal characteristic including 1/f noise over frequencies above the circadian rhythmicity. Moreover, we discovered that the PSD of the raw acceleration signal has the same characteristic. Our findings prove that the spectral scale-free nature is generally inherent to the motor activity of healthy, free-living humans, and is not limited to any particular activity calculation method.https://doi.org/10.1038/s41598-024-52905-8 |
| spellingShingle | Bálint Maczák Zoltán Gingl Gergely Vadai General spectral characteristics of human activity and its inherent scale-free fluctuations Scientific Reports |
| title | General spectral characteristics of human activity and its inherent scale-free fluctuations |
| title_full | General spectral characteristics of human activity and its inherent scale-free fluctuations |
| title_fullStr | General spectral characteristics of human activity and its inherent scale-free fluctuations |
| title_full_unstemmed | General spectral characteristics of human activity and its inherent scale-free fluctuations |
| title_short | General spectral characteristics of human activity and its inherent scale-free fluctuations |
| title_sort | general spectral characteristics of human activity and its inherent scale free fluctuations |
| url | https://doi.org/10.1038/s41598-024-52905-8 |
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