{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,19]],"date-time":"2025-11-19T14:55:51Z","timestamp":1763564151507,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,30]],"date-time":"2021-01-30T00:00:00Z","timestamp":1611964800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010661","name":"Horizon 2020","doi-asserted-by":"publisher","award":["824162"],"award-info":[{"award-number":["824162"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Digital"],"abstract":"<jats:p>Numerous experiments require low latencies in the detection and processing of the neural brain activity to be feasible, in the order of a few milliseconds from action to reaction. In this paper, a design for sub-millisecond detection and communication of the spiking activity detected by an array of 32 intracortical microelectrodes is presented, exploiting the real-time processing provided by Field Programmable Gate Array (FPGA). The design is embedded in the commercially available RHS stimulation\/recording controller from Intan Technologies, that allows recording intracortical signals and performing IntraCortical MicroStimulation (ICMS). The Spike Detector (SD) is based on the Smoothed Nonlinear Energy Operator (SNEO) and includes a novel approach to estimate an RMS-based firing-rate-independent threshold, that can be tuned to fine detect both the single Action Potential (AP) and Multi Unit Activity (MUA). A low-latency SD together with the ICMS capability, creates a powerful tool for Brain-Computer-Interface (BCI) closed-loop experiments relying on the neuronal activity-dependent stimulation. The design also includes: A third order Butterworth high-pass IIR filter and a Savitzky-Golay polynomial fitting; a privileged fast USB connection to stream the detected spikes to a host computer and a sub-milliseconds latency Universal Asynchronous Receiver-Transmitter (UART) protocol communication to send detections and receive ICMS triggers. The source code and the instruction of the project can be found on GitHub.<\/jats:p>","DOI":"10.3390\/digital1010003","type":"journal-article","created":{"date-parts":[[2021,1,30]],"date-time":"2021-01-30T21:15:51Z","timestamp":1612041351000},"page":"34-53","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["FPGA Design Integration of a 32-Microelectrodes Low-Latency Spike Detector in a Commercial System for Intracortical Recordings"],"prefix":"10.3390","volume":"1","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7593-5084","authenticated-orcid":false,"given":"Mattia","family":"Tambaro","sequence":"first","affiliation":[{"name":"Padova Neuroscience Center, University of Padua, 35131 Padua, Italy"},{"name":"Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marta","family":"Bisio","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marta","family":"Maschietto","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9110-1055","authenticated-orcid":false,"given":"Alessandro","family":"Leparulo","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0389-8023","authenticated-orcid":false,"given":"Stefano","family":"Vassanelli","sequence":"additional","affiliation":[{"name":"Padova Neuroscience Center, University of Padua, 35131 Padua, Italy"},{"name":"Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kim, G.H., Kim, K., Lee, E., An, T., Choi, W., Lim, G., and Shin, J.H. 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