# Biosignals Monitoring of First Responders for Cognitive Load Estimation in Real-Time Operation
## 6 Conclusions  
This manuscript has addressed the definition of a monitoring architecture for real time biosignals acquisition and CL correlation for FRs to be used in future emergency and disaster situations. The hardware selection, software integration, and database creation have been implemented to obtain a fully functional monitoring framework that has been tested both in-lab and in field exercises. For the biosignals hardware acquisition systems, connectivity and accuracy were the two main goals of the design. It was mandatory to obtain real-time measurements than can be acquired in isolated scenarios without connection to any cloud or server, given emergency and disaster requirements. Moreover, all elements provided different connection protocols (e.g., WiFi, Bluetooth, and USB) based on dockerized applications. However, all these applications converge to a common point, a dockerized database that stores all real-time measurements, both for its future communication to command center and FRs CL estimation. For the cognitive load estimation, a set of in-lab and practice scenarios were planned. The trials allowed testing of the correct functioning of the biosignals monitoring hardware, software, and integration. Together with the biosignals monitoring, a set of NASA-TLX questionnaires were requested from the users. Upon technical validation, several tendencies were found between the NASA-TLX questionnaires provided by the FRs and some biosignals, especially respiration rate and eye gaze. However, this relationship does not show any statistical difference, provided the reduced number of samples in each FRs' group. Nonetheless, this tendency envisions the usage of the framework proposed for a longer clinical trial to extract more information of FRs in operation and analyze whether CL quantification can be inferred. Moreover, the need to stop performing the primary activity in the real practice scenario should be an important input variable for CL estimation. This variable should be acquired by the accelerometer included in the wristband or the inertial movement estimation included in the RESCUER framework, which will surely provide new lines of research. Given the framework acquisition rate of the biosignals provided to the framework (see Table 1), it is estimated that a software running every 15 s could handle CL inference where at least five samples of the slower biosignals acquisition are collected (i.e., E4 wristband) and once the eye gaze batch is received (i.e., 10 s). Therefore, no computation problems are expected to extract the data, process it, and provide feedback to the FR to reduce the amount of information provided. Nonetheless, a longitudinal study must be planned to obtain a bigger amount of data from in-lab and real operation, where cognitive load is increased to infer a real-time model that could help modulate the information provided to FRs in operation. This modulation will allow increasing or decreasing the augmented senses (i.e., AR, augmented hearing, etc.) information that is provided to the FRs in operation, with the aim of adjusting its cognitive capabilities. Conceptualization, A.G. and P.B. ; methodology, A.G., P.B., M.A. and M.F. ; software, V.R., C.C., X.O., I.A. and P.K. ; validation, P.B., S.N., M.A., G.I., A.G. and V.R. ; formal analysis, A.G., P.B., S.N. and M.A. ; investigation, A.G., P.B., V.R., C.C., X.O., M.A., S.N., M.F., I.A., G.I., B.L.-G., P.K., I.G.O. and F.A. ; resources, F.A., I.G.O., P.B. and M.F. ; data curation, V.R. and A.G.; writing--original draft preparation, A.G., B.L.-G. and P.B. ; writing--review and editing, A.G., P.B., V.R., C.C., X.O., M.A., S.N., M.F., I.A., G.I., B.L.-G., P.K., I.G.O. and F.A. ; visualization, V.R., A.G., I.A. and X.O. ; supervision, A.G., P.B., M.F. and I.G.O. ; project administration, F.A. and A.G.; funding acquisition, F.A., P.B., I.G.O. and M.F. All authors have read and agreed to the published version of the manuscript.