For decades, electroencephalography (EEG) has been a useful tool for investigating the neural mechanisms underlying human psychological processes. However, the amount of time needed to gather EEG data means that most laboratory studies use relatively small sample sizes. Using the Muse, a portable and wireless 4-channel EEG headband, we obtained EEG recordings from 6029 subjects who ranged from 18-88 years in age while they completed a category exemplar task followed by a meditation exercise. Here, we report age-related changes in EEG power at a fine chronological scale for delta, theta, alpha, and beta bands, as well as peak alpha frequency and alpha asymmetry measures for both frontal and temporoparietal sites. We found that EEG power changed as a function of age, and that the age-related changes depended on sex and frequency band. We found an overall age-related shift in band power from lower to higher frequencies, especially for females. We also found a gradual, year-by-year slowing of the peak alpha frequency with increasing age. Finally, our analysis of alpha asymmetry revealed greater relative right frontal activity. Our results replicate several previous age- and sex-related findings, and show how some previously-observed changes during childhood extend throughout the lifespan. Unlike previous age-related EEG studies which have been limited by sample size and restricted age ranges, our work highlights the advantage of using large, representative samples to address questions about developmental brain changes. We discuss our findings in terms of their relevance to attentional processes, and brain-based models of emotional well-being and aging.
Significance Statement We collected over 6000 participants’ EEG data during two different tasks in uncontrolled environments, and identified subtle but robust sex differences in several EEG measures, as well as age-related shifts in EEG activity on a year-by-year scale. Our large sample size provided us with the power to highlight gradual age-related changes in several EEG measures, and how those changes differ between males and females, in a representative population of individuals completing the tasks in uncontrolled, natural environments.
The authors AH, KJM, PJB, LAS, and ABS declare no competing financial interests. Authors LJP, GM, and CA are current employees of InteraXon, the creators of the Muse.
Natural Sciences and Engineering Research Council of Canada (Conseil de Recherches en Sciences Naturelles et en Génie du Canada).