{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T23:46:57Z","timestamp":1780444017166,"version":"3.54.1"},"reference-count":40,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,14]],"date-time":"2022-12-14T00:00:00Z","timestamp":1670976000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000781","name":"European Research Council","doi-asserted-by":"publisher","award":["842243"],"award-info":[{"award-number":["842243"]}],"id":[{"id":"10.13039\/501100000781","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Recent studies show that the integrity of core perceptual and cognitive functions may be tested in a short time with Steady-State Visual Evoked Potentials (SSVEP) with low stimulation frequencies, between 1 and 10 Hz. Wearable EEG systems provide unique opportunities to test these brain functions on diverse populations in out-of-the-lab conditions. However, they also pose significant challenges as the number of EEG channels is typically limited, and the recording conditions might induce high noise levels, particularly for low frequencies. Here we tested the performance of Normalized Canonical Correlation Analysis (NCCA), a frequency-normalized version of CCA, to quantify SSVEP from wearable EEG data with stimulation frequencies ranging from 1 to 10 Hz. We validated NCCA on data collected with an 8-channel wearable wireless EEG system based on BioWolf, a compact, ultra-light, ultra-low-power recording platform. The results show that NCCA correctly and rapidly detects SSVEP at the stimulation frequency within a few cycles of stimulation, even at the lowest frequency (4 s recordings are sufficient for a stimulation frequency of 1 Hz), outperforming a state-of-the-art normalized power spectral measure. Importantly, no preliminary artifact correction or channel selection was required. Potential applications of these results to research and clinical studies are discussed.<\/jats:p>","DOI":"10.3390\/s22249803","type":"journal-article","created":{"date-parts":[[2022,12,14]],"date-time":"2022-12-14T03:21:52Z","timestamp":1670988112000},"page":"9803","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Efficient Low-Frequency SSVEP Detection with Wearable EEG Using Normalized Canonical Correlation Analysis"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3325-6347","authenticated-orcid":false,"given":"Victor Javier","family":"Kartsch","sequence":"first","affiliation":[{"name":"Department of Electrical, Electronic, and Information Engineering \u201cGuglielmo Marconi\u201d, University of Bologna, 40136 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9286-4687","authenticated-orcid":false,"given":"Velu Prabhakar","family":"Kumaravel","sequence":"additional","affiliation":[{"name":"Digital Society Center, Fondazione Bruno Kessler, 38123 Trento, Italy"},{"name":"Center for Mind\/Brain Sciences (CIMeC), University of Trento, 38068 Rovereto, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2807-3618","authenticated-orcid":false,"given":"Simone","family":"Benatti","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronic, and Information Engineering \u201cGuglielmo Marconi\u201d, University of Bologna, 40136 Bologna, Italy"},{"name":"Department of Sciences and Methods for Engineering, University of Modena and Reggio Emilia, 41123 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8192-9062","authenticated-orcid":false,"given":"Giorgio","family":"Vallortigara","sequence":"additional","affiliation":[{"name":"Center for Mind\/Brain Sciences (CIMeC), University of Trento, 38068 Rovereto, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8068-3806","authenticated-orcid":false,"given":"Luca","family":"Benini","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronic, and Information Engineering \u201cGuglielmo Marconi\u201d, University of Bologna, 40136 Bologna, Italy"},{"name":"Department of Information Technology and Electrical Engineering at ETH Zurich, 8092 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9047-9868","authenticated-orcid":false,"given":"Elisabetta","family":"Farella","sequence":"additional","affiliation":[{"name":"Digital Society Center, Fondazione Bruno Kessler, 38123 Trento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2362-7853","authenticated-orcid":false,"given":"Marco","family":"Buiatti","sequence":"additional","affiliation":[{"name":"Center for Mind\/Brain Sciences (CIMeC), University of Trento, 38068 Rovereto, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,14]]},"reference":[{"key":"ref_1","unstructured":"Niedermeyer, E., and da Silva, F.L. 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