Resumen

Introduction: Berger related the EEG with cognition, and we are still trying to identify which rhythms and circuits participate in learning, such as habituation. Variations in membrane potentials generate absolute power (AP) of these rhythms in direct relation to the number of involved neurons. Objective: To characterize habituation, analyzing the AP of EEG rhythms in lateral regions of both hemispheres (BH), proposing that their diminution, desynchronization (D), means activation whereas their increase, synchronization (S), means inhibition. Material and methods: The study was performed in 81 College students. The EEG was recorded with a Nicolet according to the 10/20 international system. Subjects in the waking state, with closed eyes, were photostimulated (5 Hz for 2 s, 20 times, RPh). The used UAMI/Yañez software identifies the RPh signals, selects and takes samples of 2 s before (Pre) and during RPh; it instruments the Welch periodogram, which integrates the AP of δ, θ, α, and β. We calculated the average AP (AAP) in Pre and RPh per frequency in fronto-frontal (FF), fronto-temporal (FT), temporo-temporal (TT), and temporo-occipital (TO) leads per hemisphere. AAP differences were evaluated with non-parametric tests and with the linear regression model we plotted the AAP of each Pre and RPh period, and calculated the D/S percentage change. Results: RPh increased the AAP of all four frequencies in FF, the increase in δ persisted in FT and TO and that of β was kept in all leads. The APP of θ and α did not change in FT and decreased in TT and TO. In Pre, the APP of the four frequencies diminished yielding negative slopes, particularly in α. The δ AAP increased with the first stimulations and remained high (S). AAP of β increased (S), yielding a significant positive slope in three leads of BH. AAP of θ and a decreased (D) to increase with further stimulation, yielding a D to S slope, greater in TO. Percentages of D/S change were significant for θ and α with greater intensities in three RH leads, but the same in TT. Conclusions: The D/S of θ and α indicates their participation in the recognition, and memorization of information; the S of δ and β reflects hyperpolarization of the membrane resulting from the syntonization of inhibitory interneurons and producing decreased responses, habituation.

Palabras clave: Linear regression in habituation spectral EEG power in habituation synchronization/desynchronization of δ θ α and β.

2013-12-18   |   658 visitas   |   Evalua este artículo 0 valoraciones

Vol. 65 Núm.5. Septiembre-Octubre 2013 Pags. 436-444 Rev Invest Clin 2013; 65(5-ENGLISH)