Dataset title: Bimodal EEG–fNIRS Dataset for Objective Auditory Assessment Using ASSR-like and Frequent–Rare Cortical Auditory Paradigms DOI: tvw4-am97 Principal Investigator Contact Information Name: Jhon Jairo Castañeda Gonzalez Email: jhon.castaned@postgrad.curtin.edu.au Institution: Curtin University ORCID: 0000-0003-2407-4859 Associate or Co-investigator Contact Information Name: Anjula De Silva Email: anjula.desilva@curtin.edu.au Institution: Curtin University ORCID: 0000-0001-8685-2076 Associate or Co-investigator Contact Information Name: Hanieh Bakhshayesh Email: hanieh.bakhshayesh@curtin.edu.au Institution: Curtin University ORCID: 0000-0003-2751-5496 Associate or Co-investigator Contact Information Name: Tele Tan Email: t.tan@curtin.edu.au Institution: Curtin University ORCID: 0000-0003-3195-3480 Associate or Co-investigator Contact Information Name: Dona Jayakody Email: dona.jayakody@uwa.edu.au Institution: University of Western Australia ORCID: 0000-0001-5814-4355 Date of dataset collection: 3 July 2024 – 18 October 2025 Date of dataset publication: August 2026 Keywords: EEG, fNIRS, auditory evoked responses, hearing assessment, auditory steady-state response, multimodal neuroimaging Primary dataset contact: Castañeda González, Jhon Jairo; jhon.castaned@postgrad.curtin.edu.au If necessary, further information or contact details may be found by emailing researchdata@curtin.edu.au +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ DATA INFORMATION Data description: This dataset contains simultaneous electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) recordings acquired from normal-hearing adults as part of a research study investigating multimodal neurophysiological responses to auditory stimulation. Participants underwent otoscopic examination and pure-tone air-conduction audiometric screening before data acquisition. The experimental protocol comprised two passive auditory paradigms and a resting-state condition. The first was an auditory steady-state response (ASSR)-like paradigm using simultaneous amplitude-modulated tones at carrier frequencies of 0.5, 1, 2, and 4 kHz across participant-specific Low, Medium, and High stimulus-intensity conditions. The second was a frequent–rare cortical auditory paradigm using 1- and 2-kHz tones presented in blocks with an 80:20 frequent-to-rare probability and subsequent reversal of stimulus probabilities. EEG and fNIRS were acquired simultaneously and synchronised using Lab Streaming Layer (LSL)-based event markers. The curated dataset contains data from 39 participants and has been de-identified and organised according to the Brain Imaging Data Structure (BIDS). EEG recordings are provided in a BIDS-compatible electrophysiological format and fNIRS recordings in the Shared Near Infrared Spectroscopy Format (SNIRF), together with event information and supporting JSON/TSV metadata describing the experimental conditions and recordings. Variable definitions, event coding, units, channel information and acquisition metadata are documented within the corresponding BIDS sidecar files and dataset documentation. Data collection time details: 3 July 2024 – 18 October 2025 Number of files & types: The PUBLIC_BIDS_DATASET folder contains 3,136 files recursively: 1,228 .json files, 995 .tsv files, 232 .snirf files, 226 .eeg files, 226 .vhdr files, 226 .vmrk files, two .png files, and one file without an extension (README). The top level contains 39 participant directories (sub-001 to sub-039), a sourcedata directory containing two files, and the root files dataset_description.json, participants.json, participants.tsv, and README. Special software required to open files: No proprietary software is required. The dataset follows the Brain Imaging Data Structure (BIDS). EEG recordings are provided in BrainVision-compatible format and fNIRS recordings in SNIRF format. The data can be accessed using standard BIDS- and SNIRF-compatible research software, including MNE-Python/MNE-BIDS and other compatible neuroimaging analysis packages. JSON and TSV metadata can be opened using standard text or tabular-data software. Geographic information (if relevant): Perth, Western Australia, Australia +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ REUSE INFORMATION Recommended citation: Castañeda Gonzalez, J. J., De Silva, A., Bakhshayesh, H., Tan, T., & Jayakody, D. (2026). Bimodal EEG–fNIRS Dataset for Objective Auditory Assessment Using ASSR-like and Frequent–Rare Cortical Auditory Paradigms [Dataset]. Curtin University. https://doi.org/10.25917/TVW4-AM97 This dataset is provided under a CC BY 4.0 license. More details can be found at https://creativecommons.org/licenses/by/4.0/