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Electroencephalography and clinical neurophysiology, 1990
The interindividual distributions of EEG amplitudes were evaluated in 60 healthy subjects, aged 56-76. Skew and kurtosis were used to assess the normality of the amplitude distributions in 5 frequency bands (delta, theta, alpha and 2 beta ranges) and 28 scalp derivations while the subjects were awake and rested with their eyes closed and opened. Most of the interindividual EEG amplitude distributions were not normally distributed. Two transformations were applied to the EEG amplitudes: the square root and the natural logarithm. Evaluation of skew and kurtosis indicated that the natural logarithmic transformation was more effective than the square root in reducing the positive skew and leptokurtosis that characterized the untransformed interindividual EEG amplitude distributions. For all frequency bands except theta, the log transformation rendered the distributions approximately normal in form. Correlations between log transformed EEG amplitudes and age were not statistically signif...
Brain signals such as electroencephalogram (EEG) often show oscillations at various frequencies, which are represented as distinct “bumps” in the power spectral density (PSD) of these signals. In addition, the PSD also shows a distinct reduction in power with increasing frequency, which pertains to aperiodic activity and is often termed as the “1/f” component. While a change in periodic activity in brain signals with healthy aging and mental disorders has been reported, recent studies have shown a reduction in the slope of the aperiodic activity with these factors as well. However, these studies only analysed PSD slopes over a limited frequency range (<100 Hz). To test whether the PSD slope is affected over a wider frequency range with aging and mental disorder, we collected EEG data with high sampling rate (2500 Hz) from a large population of elderly subjects (>49 years) who were healthy (N=217) or had mild cognitive impairment (MCI; N=11) or Alzheimer’s Disease (AD; N=5), an...
Neuroscience Letters, 2010
International Journal of Psychophysiology, 1993
The Neurodiagnostic journal, 2012
When the article, "EEGs in Elderly Patients: Technical and Other Considerations" was published in the American Journal of EEG Technology (AJET) in March 1980, the US elderly population was only 10% of the total US population (Hansotia et al. 1980). By the year 2030, it is projected that the elderly will account for nearly 20% of the US population (US Census Bureau 2010). Elderly patients present with a very unique presentation, suggestive of many different differential diagnoses. Elderly patients are more susceptible to seizures than the general adult population. Technologists must be knowledgeable of the normal EEG patterns, normal variants, and unique abnormalities seen in the elderly population. "Geriatric EEG is special" (Klass and Brenner 1995).
Frontiers in Aging Neuroscience, 2021
Compared with healthy older adults, patients with Alzheimer's disease show decreased alpha and beta power as well as increased delta and theta power during resting state electroencephalography (rsEEG). Findings for mild cognitive impairment (MCI), a stage of increased risk of conversion to dementia, are less conclusive. Cognitive status of 213 non-demented high-agers (mean age, 82.5 years) was classified according to a neuropsychological screening and a cognitive test battery. RsEEG was measured with eyes closed and open, and absolute power in delta, theta, alpha, and beta bands were calculated for nine regions. Results indicate no rsEEG power differences between healthy individuals and those with MCI. There were also no differences present between groups in EEG reactivity, the change in power from eyes closed to eyes open, or the topographical pattern of each frequency band. Overall, EEG reactivity was preserved in 80+-year-olds without dementia, and topographical patterns were...
Human brain …, 2006
Culture, Medicine and Psychiatry, 1996
This paper points to a convergence of formal and rhetorical features in ancient Chinese cosmobiological theory, within which is developed a view of the inner life of human emotions. Inasmuch as there is an extensive classical tradition considering the emotions in conjunction with music, one can justify a structural analysis of medical texts treating disorder in emotional life, since emotions, musical interpretation and structural analysis all deal with systems interrelated in a transformational space largely independent of objective reference and propositional coordination. Following a section of ethnolinguistic sketches to provide grounds in some phenomenological worlds recognized by Chinese people, there is a textual analysis of a classical medical source for the treatment of emotional distress. Through close examination of the compositional schema of this text, it can be demonstrated that the standard categories of correlative cosmology are arrayed within a more comprehensive structural order.
El proceso de Urbanización por Luis Unikel, 2020
INTRODUCCIÓN El proceso de urbanización y el acelerado crecimiento de la población total constituyen, sin duda alguna, dos de los fenómenos a escala mun-dial de mayor importancia en el desarrollo de la sociedad humana y del medio en que ésta se desenvuelve. La urbanización es un proceso complejo que se manifiesta a través de dos grandes fenómenos: el primero y más patente de ellos corres-ponde a la creciente concentración de la población urbana, que opera a través del crecimiento de las localidades urbanas existentes y del surgimiento de nuevas localidades urbanas. 2 El segundo, más difícil de definir, consite en la evolución de la forma de vida de la pobla-ción, de un tipo tradicional-rural a otro moderno-urbano. 3
Basic & Clinical Pharmacology & Toxicology, 2014
Revista Colombiana de Nefrología, 2020
Revista Nexus Comunicación, 2015
Journal of global sport management, 2018
Proceedings of the AAAI Conference on Artificial Intelligence