PHYSIOLOGICAL RESEARCH  ISSN 0862-8408 (print)  ISSN 1802-9973 (online) © 2012 Institute of Physiology v.v.i., Academy of Sciences of the Czech Republic, Prague, Czech Republic Fax +420 241 062 164, e-mail: physres@biomed.cas.cz, www.biomed.cas.cz/physiolres Physiol. Res. 61 (Suppl. 2): S119-S127, 2012 Gender Impact on Electrophysiological Activity of the Brain J. LANGROVÁ 1 , J. KREMLÁČEK 1 , M. KUBA 1 , Z. KUBOVÁ 1 , J. SZANYI 1 1 Department of Pathophysiology, Faculty of Medicine in Hradec Králové, Charles University in Prague, Hradec Králové, Czech Republic Received March 19, 2012 Accepted July 2, 2012 Summary Gender is presumed to be one of the factors causing interindividual variability in the brain’s electrophysiological parameters. Our aim was to characterize the role of gender in visual evoked potentials (VEPs), event-related potentials (ERPs), visual mismatch negativity (vMMN) and the spectral characteristics of the EEG. We examined 42 healthy volunteers (21 women and 21 men, aged 20-29 years). We measured VEPs in response to pattern-reversal and motion-onset stimulation, ERPs in an oddball paradigm and vMMN in response to a combination of motion directions presented in the visual periphery. P100 peak latency for 40’ reversal VEPs was significantly shorter in women than in men as determined using a non-parametric Wilcoxon signed-rank test. In addition, women showed higher relative EEG spectral power in the alpha band (p=0.023) and lower power in the theta band (p=0.004). Our results in this small but homogeneous group of subjects confirm previously reported gender influences on pattern-reversal VEPs and the EEG frequency spectrum. Gender should be taken into consideration in establishing norms on these measures. We found no statistically significant differences between women and men for any of the other stimuli presented. Key words Gender • Pattern-reversal VEPs • Motion VEPs • Event related potentials • Visual mismatch negativity Corresponding author Jana Langrová, Department of Pathophysiology, Charles University in Prague, Faculty of Medicine in Hradec Králové, Šimkova 870, 500 38 Hradec Králové, Czech Republic. E-mail: langrovaj@lfhk.cuni.cz Introduction Visual evoked potentials (VEPs) are used to interrogate the visual pathway from the retina up through high-level visual cortices. These responses can be measured noninvasively and at low cost. The stimulus most commonly used in VEP acquisition is a luminance- reversing high contrast checkerboard, which predominantly activates the primary visual cortex (V1) (Seki et al. 1996, Brecelj et al. 1998). Pattern-reversal VEPs (P-VEPs) P100 peak latency and amplitude depend heavily on the pattern’s contrast and the visual acuity of the tested subjects (Kubova et al. 1995). Onset of motion in the visual field activates the dorsal visual stream and evokes motion-onset VEPs (M-VEPs), which are relatively independent of contrast and visual acuity (Kubova et al. 1995). Detection of event-related potentials (ERPs) such as the visual mismatch negativity (vMMN) or the oddball P300 is an important step toward obtaining insight into higher-order cognitive functions. Combining information from these various types of visual evoked potentials can extend our understanding of brain function and elucidate the causes of many diseases that affect the central nervous system (CNS). Gender is presumed to be one of the factors causing interindividual variation in the electrophysiological parameters of the human brain. Many studies have examined gender effects on P-VEPs (e.g., Fenwick et al. 1981, Allison et al. 1984, Cohn et al. 1985, Malcolm et al. 2002, Gregori et al. 2006) and, more recently, on ERPs (Polich and Kok 1995, Hoffman and Polich 1999, Sangal and Sangal 1996, Steffensen et al. 2008). The effect of gender on P-VEP parameters is inconsistent across studies. While some studies have https://doi.org/10.33549/physiolres.932421