Changes in Electroencephalographic Power Spectra Associated with Reproductive Status in Frog

Abstract

AbstractElectroencephalogram (EEG) waveforms reflect the summed slow potentials generated by cortical neurons and can therefore be used to infer functional processes. In many species, individuals in the reproductive stage are more active and sensitive to species-typical stimuli than those in the non-reproductive stage. In the present study, changes in EEG power spectra were examined with respect to reproductive status in the music frog, Babina daunchina. The results indicated that in the reproductive stage, (1) power spectra of all EEG oscillations except for theta were significantly higher than in the non-reproductive stage; (2) for delta, significant increase of the power spectrum only appeared in the right hemisphere; and (3) the brain exhibited left-dominance of EEG spectra in the telencephalon and right-dominance of EEG spectra in the mesencephalon, providing evidence of lateralization of function. It is likely that sex hormone differences in the reproductive stage mediate these phenomena, through expression of their receptors, transcriptional regulatory elements, in specific regions of the forebrain and midbrain.KeywordsEEGpower spectrumreproductive stagelateralization of function