Acta Medica Iranica 2017. 55(8):502-506.

Index of Theta/Alpha Ratio of the Quantitative Electroencephalogram in Alzheimer's Disease: A Case-Control Study
Golshan Fahimi, Seyed Mahmoud Tabatabaei, Elnaz Fahimi, Hamid Rajebi


Alzheimer's disease (AD) is a devastating neurodegenerative disorder in human beings associated with cognitive, behavioral and motor impairments. The main symptom of AD is dementia, which causes difficulties in carrying out daily practices. Brain waves are altered in people with AD. Relative indices of brain waves can be beneficial in the diagnosis of AD. In this case-control study, 50 patients with AD and 50 matched healthy individuals were enrolled in case and control groups respectively. With recording and analyzing of brain waves with the utilization of quantitative electroencephalogram (QEEG), index of theta/alpha ratio was assessed in both groups. The index of theta/alpha ratio was significantly higher in patients with AD in comparison to healthy individuals (P<0.05). Index of theta/alpha ratio obtained by QEEG provides a non-invasive diagnostic marker of AD, which may be helpful in identification of non-advanced disease in susceptible individuals.


Alzheimer's disease; Theta wave; Alpha wave; Theta/alpha ratio

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