{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,6]],"date-time":"2025-11-06T00:59:50Z","timestamp":1762390790484,"version":"build-2065373602"},"reference-count":46,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,7,14]],"date-time":"2018-07-14T00:00:00Z","timestamp":1531526400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010198","name":"Ministerio de Econom\u00eda, Industria y Competitividad, Gobierno de Espa\u00f1a","doi-asserted-by":"publisher","award":["PSI2013-48260-C3-2-R"],"award-info":[{"award-number":["PSI2013-48260-C3-2-R"]}],"id":[{"id":"10.13039\/501100010198","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Neurofeedback is a self-regulation technique that can be applied to learn to voluntarily control cerebral activity in specific brain regions. In this work, a Transcranial Doppler-based configurable neurofeedback system is proposed and described. The hardware configuration is based on the Red Pitaya board, which gives great flexibility and processing power to the system. The parameter to be trained can be selected between several temporal, spectral, or complexity features from the cerebral blood flow velocity signal in different vessels. As previous studies have found alterations in these parameters in chronic pain patients, the system could be applied to help them to voluntarily control these parameters. Two protocols based on different temporal lengths of the training periods have been proposed and tested with six healthy subjects that were randomly assigned to one of the protocols at the beginning of the procedure. For the purposes of the testing, the trained parameter was the mean cerebral blood flow velocity in the aggregated data from the two anterior cerebral arteries. Results show that, using the proposed neurofeedback system, the two groups of healthy volunteers can learn to self-regulate a parameter from their brain activity in a reduced number of training sessions.<\/jats:p>","DOI":"10.3390\/s18072278","type":"journal-article","created":{"date-parts":[[2018,7,16]],"date-time":"2018-07-16T04:05:33Z","timestamp":1531713933000},"page":"2278","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Design and Validation of an FPGA-Based Configurable Transcranial Doppler Neurofeedback System for Chronic Pain Patients"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9213-1443","authenticated-orcid":false,"given":"Beatriz","family":"Rey","sequence":"first","affiliation":[{"name":"Departamento de Ingenier\u00eda Gr\u00e1fica, Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4781-6368","authenticated-orcid":false,"given":"Alejandro","family":"Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Gr\u00e1fica, Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Enrique","family":"Llor\u00e9ns-Bufort","sequence":"additional","affiliation":[{"name":"Instituto de Instrumentaci\u00f3n para Imagen Molecular (I3M), Centro Mixto CSIC\u2014Universitat Polit\u00e8cnica de Val\u00e8ncia\u2014CIEMAT, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jos\u00e9","family":"Tembl","sequence":"additional","affiliation":[{"name":"Departamento de Neurolog\u00eda, Hospital Universitari i Polit\u00e8cnic La Fe, 46026 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miguel \u00c1ngel","family":"Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"Departamento de Personalidad, Evaluaci\u00f3n y Tratamiento Psicol\u00f3gico, Universidad de Granada, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8652-948X","authenticated-orcid":false,"given":"Pedro","family":"Montoya","sequence":"additional","affiliation":[{"name":"Instituto Universitario de Investigaci\u00f3n en Ciencias de la Salud, Universitat Illes Balears, 07122 Palma, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vicente","family":"Herrero-Bosch","sequence":"additional","affiliation":[{"name":"Instituto de Instrumentaci\u00f3n para Imagen Molecular (I3M), Centro Mixto CSIC\u2014Universitat Polit\u00e8cnica de Val\u00e8ncia\u2014CIEMAT, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jose M.","family":"Monzo","sequence":"additional","affiliation":[{"name":"Instituto de Instrumentaci\u00f3n para Imagen Molecular (I3M), Centro Mixto CSIC\u2014Universitat Polit\u00e8cnica de Val\u00e8ncia\u2014CIEMAT, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,7,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1016\/S0074-7742(09)86008-X","article-title":"Neurofeedback and brain-computer interface clinical applications","volume":"86","author":"Birbaumer","year":"2009","journal-title":"Int. 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