NEUROSYNC Protocol: Multimodal Auditory Stimulation Under Chromatic Ambient Lighting

Puneet Tomar; Anna Laura Pisello

Apr 09, 2026

NEUROSYNC Protocol: Multimodal Auditory Stimulation Under Chromatic Ambient Lighting

DOI

https://dx.doi.org/10.17504/protocols.io.rm7vz4e52lx1/v1

Puneet Tomar¹,
Anna Laura Pisello^1,2

¹EAPLAB at CIRIAF “Interuniversity research center on pollution and environment Mauro Felli”, University of Perugia, Italy;
²Department of Engineering, University of Perugia, Italy

MuSIC

Puneet Tomar

La Rochelle Université

DOI: https://dx.doi.org/10.17504/protocols.io.rm7vz4e52lx1/v1

Protocol Citation: Puneet Tomar, Anna Laura Pisello 2026. NEUROSYNC Protocol: Multimodal Auditory Stimulation Under Chromatic Ambient Lighting. protocols.io https://dx.doi.org/10.17504/protocols.io.rm7vz4e52lx1/v1

License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Protocol status: Working

We use this protocol and it's working

Created: March 31, 2026

Last Modified: April 09, 2026

Protocol Integer ID: 314174

Keywords: NEUROSYNC, chromatic ambient lighting, auditory stimulation, binaural beats, EEG, electrodermal activity, blood volume pulse, wearable physiology, participant-facing video, verbal-semantic task, visuospatial task, static experiment runner, multimodal protocol, multimodal auditory stimulation under chromatic ambient lighting neurosync, chromatic ambient lighting neurosync, multimodal auditory stimulation, wearable neurophysiology, hz auditory stimulation, responses to auditory stimulation, neurosync protocol, multimodal acquisition, blue lighting group, dependent cognitive engagement, baseline recording, participant instruction, visuospatial illusion task, session task order, study around prefrontal laterality, facing video recording, baseline survey, session, subject protocol, participant

Funders Acknowledgements:

European Union’s Horizon Europe research and innovation programme under the Marie Skłodowska-Curie Doctoral Networks

Grant ID: 101073357

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Abstract

NEUROSYNC is a single-session multimodal human-subject protocol designed to examine responses to auditory stimulation under chromatic ambient lighting. The study combines red and blue lighting groups with a fixed within-session task order consisting of a baseline survey, acclimation, eyes-open baseline recording, a verbal-semantic task delivered with 10 Hz auditory stimulation, a post-task survey, a visuospatial illusion task delivered with 40 Hz auditory stimulation, and a final post-task survey. Multimodal acquisition includes wearable neurophysiology and autonomic physiology, repeated self-report, and participant-facing video recording. The original scientific draft framed the study around prefrontal laterality, autonomic regulation, and task-dependent cognitive engagement; the implemented platform provides the exact stage order, timing, and participant instructions used during data collection. This protocol preserves both layers so that the study can be understood, reproduced, and cited accurately.

Guidelines

Use this protocol for one participant per session under one assigned lighting condition, red or blue. Start external physiology and video recordings before the Neurosync platform begins. Treat the platform application as a participant-facing static experiment runner only. It does not store trial-level task responses and it does not provide hardware-trigger synchronization.
Interpret task-block contrasts conservatively because task order is fixed. Task block 1 is verbal-semantic with continuous 10 Hz auditory stimulation. Task block 2 is visuospatial with continuous 40 Hz auditory stimulation. 

Materials

Facility and Lighting
controlled indoor test room such as NEXT.ROOM
four 60 × 60 cm LED panels 
two RGB reflectors
artificial lighting as the primary visual manipulation
daylight control such as window shading

Participant-Facing Hardware and Software
desktop or laptop computer for the NEUROSYNC browser workflow
Firefox browser on Windows 11 in the collected implementation
internet access for embedded Google Forms
Sony WH-1000XM4 headphones

Stimuli
10 Hz auditory stimulus for task block 1
40 Hz auditory stimulus for task block 2
verbal-semantic audio set with 10 items
visuospatial illusion image set with 10 items

Recording Systems
Muse S EEG device 
Empatica EmbracePlus wearable for peripheral physiology
CZUR Halo webcam positioned in front of the participant

Recorded Streams
EEG
electrodermal activity
blood volume pulse
skin temperature
accelerometry
participant-facing video
baseline survey responses
repeated post-task survey responses
session timestamps and operator notes

Archived Lighting Measurements
White + Blue: approximately 216.8 lx, CCT 4359 K
White + Red: approximately 221.3 lx, CCT 3750 K

Troubleshooting

Problem

Embedded survey does not load or submit

Solution

Possible cause: Internet connection is unavailable or Google Forms is delayed. Action: Confirm internet access, reload the survey page, and record the delay or restart in the session log.

Problem

No audio or poor headphone playback

Solution

Possible cause: Headphones are disconnected, muted, or incorrectly selected as the audio output. Action: Check the headphone connection, system volume, and browser audio output before continuing.

Problem

EEG signal quality is poor

Solution

Possible cause: Sensor contact is unstable, headset fit is incorrect, or movement is excessive. Action: Refit the Muse S device, check electrode contact, minimize participant movement, and record any restart or channel-quality issue in the session log.

Problem

Peripheral wearable is not recording correctly

Solution

Possible cause: Loose fit, poor skin contact, or recording start failure. Action: Refit the Empatica EmbracePlus wearable, confirm recording status, and document any interruption or restart.

Problem

Participant does not complete a survey within the expected time

Solution

Possible cause: Delayed response, confusion, or external interruption. Action: Allow completion when appropriate, record the delay, and preserve the actual survey timestamp for later alignment.

Problem

Acclimation or baseline period is shortened

Solution

Possible cause: Operator interruption, participant discomfort, or platform restart. Action: Continue the session if safe to do so, but record the shortened interval clearly in the session log.

Problem

Session timing no longer matches nominal platform timing

Solution

Possible cause: Manual pauses, restarts, survey delays, or recording interruptions. Action: Preserve actual start and end timestamps, retain survey timestamps, and document all deviations for retrospective synchronization.

Problem

One modality is incomplete while others continue

Solution

Possible cause: Device-specific stop event or restart during acquisition. Action: Do not assume the entire session is invalid. Record the affected modality, preserve the remaining data streams, and apply modality-specific quality control during analysis.

Safety warnings

Do not describe the browser application as a full acquisition system. Survey responses are collected externally through Google Forms, and physiology and video are recorded outside the browser application. Recruitment source, explicit eligibility thresholds, compensation details, exact device sampling rates, firmware versions, exact LED model identifiers, audio calibration procedure, and webcam frame-rate details are not fully preserved in the current archive and should not be invented.

Ethics statement

This study was conducted under approval from the University of Perugia Ethical Board dated 2024-03-15 (Protocol 11/2024, No. 91356). All participants provided informed consent before participation. Consent was obtained electronically and explicitly included consent for video recording. Participants were debriefed after completion, and confidentiality and anonymity were safeguarded by excluding personal identifiers from the dataset.

Before start

Confirm the assigned lighting condition. Prepare the room, participant-facing computer, headphones, EEG system, peripheral wearable, webcam, and survey connectivity. Confirm that all external recording systems are ready. Prepare a session log for start times, stop times, restarts, interruptions, survey delays, shortened acclimation, and signal-quality notes. 

Synopsis

The study was run as an in-person laboratory session series between 2025-02-26 and 2025-03-17 in the NEXT.ROOM facility described by Vittori et al. The archive supports:
40 single-participant sessions
20 red-light sessions
20 blue-light sessions
complete survey, video, accelerometry, temperature, EDA, and BVP source coverage across all 40 sessions
EEG source coverage for 39 of 40 sessions

The room was maintained near standard indoor laboratory conditions around 22 ± 1 º C, so the experiment should be described as having been performed under normal indoor thermal-comfort conditions for a seated laboratory session rather than under a separate thermal manipulation. The nominal Neurosync platform protocol is ~50 minutes long, excluding manual transitions. 

Stage 1. Session Preparation

25m

Step 1.2 Prepare the participant station
Open the NEUROSYNC start page, confirm internet access for embedded Google Forms, and verify headphone playback.

Step 1.3 Prepare the recording systems
Prepare the Muse S EEG device, Empatica EmbracePlus wearable, and CZUR Halo webcam. Confirm that the webcam faces the seated participant.

Step 1.1 Prepare the environment
Set the room to the assigned chromatic ambient lighting condition, red or blue. Confirm that artificial lighting is the dominant visual exposure.

10m

Step 1.4 Prepare the session log
Open the session log and be ready to record start times, stop times, restarts, interruptions, survey delays, shortened acclimation, and sensor-quality notes.

Stage 2. Participant Intake and Setup

10m

Step 2.1 Confirm consent and session identity
Confirm electronic consent, including consent for video recording. Confirm the participant identifier and assigned lighting condition.

Step 2.2 Seat and fit the participant
Seat the participant at the test station and fit the wearable devices.

Step 2.3 Start external recordings
Start EEG, peripheral physiology, and participant-facing video recording before the browser-guided sequence begins.

Stage 3. Launch the Neurosync Platform → Acclimation

10m

Step 3.1 Open the welcome page
Display platform homepage and confirm readiness with the participant.

Step 3.2 Run the instructions and guidelines 
Open instructions and guidelines page on the platform

Step 3.3 Run the general survey form
Continue running the acclimation period

Stage 4. Acclimated → Baseline Recording

Step 4.1  Acclimation under chromatic ambient lighting
Settle into a comfortable posture, look forward, and allow the session environment to stabilize before baseline recording begins.

Step 4.2 Run the resting baseline
Open baseline and run the eyes-open resting baseline for 300 seconds while external recordings continue.

Stage 5. Task Block 1: Verbal-Semantic Processing with 10 Hz Auditory Stimulation

11m 10s

Step 5.1 Launch the task introduction
Open Verbal-semantic task under 10 Hz stimulation and present the manual introduction page.

Step 5.2 Begin the task block
Start task block 1 and allow the continuous 10 Hz auditory stimulation to play during the block.

10s

Step 5.3 Complete the 10 task items
Run the 10 verbal-semantic items at 60 seconds each. Participants respond using one of three selections:
there was an inconsistency in the sentence
there was no inconsistency in the sentence
there was an inconsistency in the sentence but it was corrected

10m

Stage 6. Post-Task Survey 1

Step 6.1 Show the post-task survey introduction
Open first post task survey and present the post-task survey introduction

30s

Step 6.2 Run the post-task survey form
Keep survey open for the embedded post-task survey form until submitted

Step 6.3 Survey content note
The repeated post-task survey includes task difficulty, alertness or relaxation, emotional stability, engagement, focus, cognitive load, emotional valence and arousal, and indoor-environment perception and satisfaction items.

30s

Stage 7. Task Block 2: Visuospatial Illusion Processing with 40 Hz Auditory Stimulation

11m 10s

Step 7.1 Launch the task introduction
Open Visuospatial illusion task under 40 Hz stimulation and present the manual introduction page

Step 7.2 Begin the task block
Start task block 2 and allow the continuous 40 Hz auditory stimulation to play during the block.

10s

Step 7.3 Complete the 10 task items
Run the 10 visuospatial illusion items at 60 seconds each. Participants respond using one of three selections:
I solved the puzzle
I could not solve the puzzle
I am not sure whether there is a solution

10m

Stage 8. Post-Task Survey 2 → Session Close

Step 8.1 Show the second post-task survey introduction
Open second post task survey and present the post-task survey introduction

30s

Step 8.2 Run the second post-task survey form
Keep survey open for the embedded post-task survey form until submitted. 

Step 8.3 Close the session
Display finish page, stop the external recordings, and hand the session back to the operator for completion and debriefing.

30s

Stage 9. After the Session

10m

Step 9.1 Secure the recorded files
Confirm that survey timestamps, EEG, peripheral physiology, and participant-facing video files were captured.

Step 9.2 Record deviations and quality issues
Log any restarts, shortened acclimation, delayed surveys, platform crashes, incomplete recordings, or channel-quality issues.

Step 9.3 Preserve synchronization anchors
Preserve the actual session start and end timestamps and any operator notes needed for later retrospective alignment of browser stages, survey timestamps, and recorded modalities.

Protocol references

Xia T, Song L, Wang TT, Tan L, Mo L. Exploring the Effect of Red and Blue on Cognitive Task Performances. Front Psychol. 2016;7:784. doi:10.3389/fpsyg.2016.00784.
Alkozei A, Smith R, Pisner DA, Vanuk JR, Berryhill SM, Fridman A, Shane BR, Knight SA, Killgore WDS. Exposure to Blue Light Increases Subsequent Functional Activation of the Prefrontal Cortex During Performance of a Working Memory Task. Sleep. 2016;39(9):1671-1680. doi:10.5665/sleep.6090.
Cai Q, Van der Haegen L, Brysbaert M. Complementary hemispheric specialization for language production and visuospatial attention. Proc Natl Acad Sci U S A. 2013;110(4):E322-E330. doi:10.1073/pnas.1212956110.
Ross B, Lopez MD. 40-Hz Binaural beats enhance training to mitigate the attentional blink. Sci Rep. 2020;10:7002. doi:10.1038/s41598-020-63980-y.
Schwarz DWF, Taylor P. Human auditory steady state responses to binaural and monaural beats. Clin Neurophysiol. 2005;116(3):658-668. doi:10.1016/j.clinph.2004.09.014.
Smith EE, Reznik SJ, Stewart JL, Allen JJB. Assessing and Conceptualizing Frontal EEG Asymmetry: An Updated Primer on Recording, Processing, Analyzing, and Interpreting Frontal Alpha Asymmetry. Int J Psychophysiol. 2017;111:98-114. doi:10.1016/j.ijpsycho.2016.11.005.
Boffet A, Arsac LM, Ibanez V, Sauvet F, Deschodt-Arsac V. Detection of Cognitive Load Modulation by EDA and HRV. Sensors (Basel). 2025;25(8):2343. doi:10.3390/s25082343.
Stuldreher IV, Thammasan N, van Erp JBF, Brouwer AM. Physiological Synchrony in EEG, Electrodermal Activity and Heart Rate Detects Attentionally Relevant Events in Time. Front Neurosci. 2020;14:575521. doi:10.3389/fnins.2020.575521.
Vittori F, Chiatti C, Pigliautile I, Pisello AL. The NEXT.ROOM: Design principles and systems trials of a novel test room aimed at deepening our knowledge on human comfort. Build Environ. 2022;211:108744. doi:10.1016/j.buildenv.2021.108744. 

Acknowledgements

This project has received funding from the European Union's Horizon Europe research and innovation programme under the Marie Sklodowska-Curie Doctoral Networks Grant Agreement No. 101073357.