Estudo eletroencefalográfico dos ritmos observados nas áreas corticais sensoriomotoras durante as fases do ciclo menstrual

Abstract

Motor imagery (IM) has been applied to improve performance in sports activities and rehabilitation of motor sequelae resulting from neurological diseases, such as stroke and Parkinson's disease. Studies suggest that the fluctuation of female sex steroids (FSS) throughout the menstrual cycle may be involved in the performance of motor and spatial abilities observed in motor tests. In this context, the present study aimed to investigate the influence of FSS on sensorimotor cognitive processes during the practice of kinesthetic motor imagery (KMI) in 30 healthy women, aged between 18 and 30 years, right-handed, in regular menstrual cycle and that they did not use hormonal contraceptives. During the research, KMI was applied in 3 different phases of the menstrual cycle (menstrual, follicular and luteal). Cortical activity was monitored using electroencephalography (EEG), and event-related desynchronization (ERD) data were recorded for normal distribution for mu and beta rhythms, for the left and right hemispheres (C3 and C4, respectively). In the analysis, it was not possible to find a significant difference between the phases of the cycle for the mu-ERD (p = 0.08) or between the cerebral hemispheres (p = 0.22). The follicular phase showed a higher beta-ERD than the menstrual phase (p = 0.013) and the luteal phase (p = 0.026). No association was observed between estradiol and progesterone and beta-ERD activity. In the complementary analysis with data from the late follicular phase of 21 participants, beta-ERD was higher at electrode C3 when compared to electrode C4. These results allow us to suggest that hormonal variations during the menstrual cycle influence motor imaging, since there was a facilitation in the sensorimotor cortical areas involved in the generation of beta rhythm during the follicular phase. As motor imaging is a tool used for the treatment and rehabilitation of patients with motor disabilities, the relevance of considering the intensification of this therapeutic modality in the follicular phase, as well as for the training of motor skills in female athletes may be recommended.