title: Decrease of delta oscillatory responses is associated with increased age in healthy elderly.
abstract: The purpose of this study was to investigate changes in delta event-related oscillations (EROs) in younger and older healthy elderly subjects. We hypothesized that delta EROs were affected by age-related changes, which could be reflected in a visual oddball paradigm.
  
  
  
  The study included two groups of subjects, 17 younger healthy elderly (mean age: 63.1±2.8years) and 17 gender- and education-matched older healthy elderly (mean age: 79.6±5.2years), who performed a visual oddball paradigm. EEG was recorded from F3, Fz, F4, C3, Cz, C4, P3, Pz, P4, O1, Oz and O2 locations. Peak-to-peak amplitudes of delta (0.5-3Hz) target ERO responses during the post-stimulus 0-800ms time window were measured. Repeated measures of ANOVA was used to analyze four locations (frontal, central, parietal, occipital), at three sagittal (left, midline, right) sites. Independent t-tests were applied for post-hoc analyses.
  
  
  
  The older healthy elderly group had 16-25% lower values for the maximum peak-to-peak amplitudes of delta ERO compared with the younger healthy elderly group over frontal (p<0.003), central (p<0.0001) and parietal (p<0.007) locations [F3.96=4.396, p=0.015]. Furthermore, there was a moderate negative correlation between age and Cz peak-to-peak amplitude of target delta responses [r=-0.401, p<0.02], indicating the notion that peak-to-peak amplitude of Cz decreases as age increases.
  
  
  
  In the present study younger healthy elderly showed significantly higher event-related delta responses than older healthy elderly at frontal, central and parietal locations. Moreover, delta ERO responses decreased in accordance with age.
authors: Department of Psychology, Dokuz Eylül University, Izmir 35160, Turkey; Department of Neurosciences, Dokuz Eylül University, Izmir 35340, Turkey; Brain Dynamics, Cognition and Complex Systems Research Center, Istanbul Kültür University, Istanbul 34156, Turkey.
authors: Derya Durusu
authors: DD
authors: Emek-Savaş
authors: Brain Dynamics, Cognition and Complex Systems Research Center, Istanbul Kültür University, Istanbul 34156, Turkey.
authors: Bahar
authors: B
authors: Güntekin
authors: Department of Neurosciences, Dokuz Eylül University, Izmir 35340, Turkey; Brain Dynamics, Cognition and Complex Systems Research Center, Istanbul Kültür University, Istanbul 34156, Turkey; Department of Neurology, Dokuz Eylül University Medical School, Izmir 35340, Turkey; Brain Dynamics Multidisciplinary Research Center, Dokuz Eylül University, Izmir 35340, Turkey.
authors: Görsev G
authors: GG
authors: Yener
authors: Brain Dynamics, Cognition and Complex Systems Research Center, Istanbul Kültür University, Istanbul 34156, Turkey. Electronic address: e.basar@iku.edu.tr.
authors: Erol
authors: E
authors: Başar
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001683:Biological Clocks / Q000502:physiology; D001921:Brain / Q000502:physiology*; D003700:Delta Rhythm / Q000502:physiology*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation
keywords: Aging; Delta; Event-related oscillations; Healthy elderly; P300