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There are different such technologies, and electroencephalography (EEG) is an example. One of the most common EEG control methods is based on detecting changes in sensorimotor rhythms (SMRs) during motor imagery (MI). The aim of this study was to assess the laterality of cortical function when performing MI of the lower limb. Brain signals from five subjects were analyzed in two conditions, during exoskeleton-assisted gait and while static. Three different EEG electrode configurations were evaluated: covering both hemispheres, covering the non-dominant hemisphere and covering the dominant hemisphere. In addition, the evolution of performance and laterality with practice was assessed. Although sightly superior results were achieved with information from all electrodes, differences between electrode configurations were not statistically significant. Regarding the evolution during the experimental sessions, the performance of the BCI generally evolved positively the higher the experience was.<\/jats:p>","DOI":"10.3390\/sym13091746","type":"journal-article","created":{"date-parts":[[2021,9,21]],"date-time":"2021-09-21T22:35:20Z","timestamp":1632263720000},"page":"1746","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Brain Symmetry Analysis during the Use of a BCI Based on Motor Imagery for the Control of a Lower-Limb Exoskeleton"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2256-757X","authenticated-orcid":false,"given":"Laura","family":"Ferrero","sequence":"first","affiliation":[{"name":"Brain-Machine Interface System Lab, Miguel Hern\u00e1ndez University of Elche, 03202 Elche, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4269-1554","authenticated-orcid":false,"given":"Mario","family":"Ortiz","sequence":"additional","affiliation":[{"name":"Brain-Machine Interface System Lab, Miguel Hern\u00e1ndez University of Elche, 03202 Elche, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7000-5390","authenticated-orcid":false,"given":"Vicente","family":"Quiles","sequence":"additional","affiliation":[{"name":"Brain-Machine Interface System Lab, Miguel Hern\u00e1ndez University of Elche, 03202 Elche, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8057-5952","authenticated-orcid":false,"given":"Eduardo","family":"I\u00e1\u00f1ez","sequence":"additional","affiliation":[{"name":"Brain-Machine Interface System Lab, Miguel Hern\u00e1ndez University of Elche, 03202 Elche, Spain"}]},{"given":"Jos\u00e9 A.","family":"Flores","sequence":"additional","affiliation":[{"name":"Department of Engineering, Miguel Hern\u00e1ndez University of Elche, 03202 Elche, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5548-9657","authenticated-orcid":false,"given":"Jos\u00e9 M.","family":"Azor\u00edn","sequence":"additional","affiliation":[{"name":"Brain-Machine Interface System Lab, Miguel Hern\u00e1ndez University of Elche, 03202 Elche, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1265","DOI":"10.1007\/s00702-007-0763-z","article-title":"Motor imagery and action observation: Cognitive tools for rehabilitation","volume":"114","author":"Mulder","year":"2007","journal-title":"J. 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