{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:47:23Z","timestamp":1760240843083,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2019,10,2]],"date-time":"2019-10-02T00:00:00Z","timestamp":1569974400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Sun Yat-sen University, Taiwan","award":["CMRPG8I0371"],"award-info":[{"award-number":["CMRPG8I0371"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Mobile electroencephalogram (EEG)-sensing technologies have rapidly progressed and made the access of neuroelectrical brain activity outside the laboratory in everyday life more realistic. However, most existing EEG headsets exhibit a fixed design, whereby its immobile montage in terms of electrode density and coverage inevitably poses a great challenge with applicability and generalizability to the fundamental study and application of the brain-computer interface (BCI). In this study, a cost-efficient, custom EEG-electrode holder infrastructure was designed through the assembly of primary components, including the sensor-positioning ring, inter-ring bridge, and bridge shield. It allows a user to (re)assemble a compact holder grid to accommodate a desired number of electrodes only to the regions of interest of the brain and iteratively adapt it to a given head size for optimal electrode-scalp contact and signal quality. This study empirically demonstrated its easy-to-fabricate nature by a low-end fused deposition modeling (FDM) 3D printer and proved its practicability of capturing event-related potential (ERP) and steady-state visual-evoked potential (SSVEP) signatures over 15 subjects. This paper highlights the possibilities for a cost-efficient electrode-holder assembly infrastructure with replaceable montage, flexibly retrofitted in an unlimited fashion, for an individual for distinctive fundamental EEG studies and BCI applications.<\/jats:p>","DOI":"10.3390\/s19194273","type":"journal-article","created":{"date-parts":[[2019,10,2]],"date-time":"2019-10-02T08:17:54Z","timestamp":1570004274000},"page":"4273","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Cost-efficient and Custom Electrode-holder Assembly Infrastructure for EEG Recordings"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3434-9118","authenticated-orcid":false,"given":"Yuan-Pin","family":"Lin","sequence":"first","affiliation":[{"name":"Laboratory for Neuroergonomics, Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan"}]},{"given":"Ting-Yu","family":"Chen","sequence":"additional","affiliation":[{"name":"Laboratory for Neuroergonomics, Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6034-8944","authenticated-orcid":false,"given":"Wei-Jen","family":"Chen","sequence":"additional","affiliation":[{"name":"Laboratory for Neuroergonomics, Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan"},{"name":"Department of Computer Science and Engineering, National Sun Yat-sen University, Kaohsiung 80424, Taiwan"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"150","DOI":"10.3389\/fnhum.2017.00150","article-title":"Systems, Subjects, Sessions: To What Extent Do These Factors Influence EEG Data?","volume":"11","author":"Melnik","year":"2017","journal-title":"Front. 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