Background
NEUROID is a technique that employ signals gathered from the operator to characterize Human Factors like Mental Workload, Stress, Vigilance, and Engagement from a neurophysiological perspective. NEUROID aims at providing information linked to the insights of the operators while interacting with the surrounding environments (e.g. aircraft cockpit, ship commands) and executing operative tasks without interfering with them, and it allows to adapting the system itself depending on the operators’ psychophysical states.
The NEUROID was developed by UNISAP and validated together with DBL and ENAC in several operational contexts like Automotive, Aviation, and ATM, to determine how the combination of the considered HFs can be used to define the Human Performance Envelope (HPE) of the operator, and consequently employed to monitor the operator while interacting with high-automated system and unexpected malfunctions, or under challenging and demanding situations.
image courtesy Stress project
Key Concepts
The NEUROID is based on data-mining and machine-learning algorithms to make the HFs neurophysiological models fitting each operator and minimize inter-user variability, therefore obtaining reliable operator’s assessment. More than 88% of all general aviation accidents are attributed to human error. Therefore, NEUROID generates an innovative and systematic approach to quantify and objectively measure HFs by taking into account, at the same time, the behaviours, emotions, and the mental reactions of the operators themselves, and integrating them with the data related to accidents and incidents investigations.
The general concept at the base of NEUROID is that brain, body, and operator’s experience are reciprocally coupled, and that accurate assessment of the operator’s can only be achieved through a well-defined combination of all the available data. Each biological activity is regulated by the human Nervous System, therefore variations of such biological activities correspond to internal reactions because of modification of external (environment) and internal (mental, motivations, emotions, etc.) factors. There are numerous types of neurophysiological measures, such as Electroencephalogram (EEG, related to brain activity), Electrocardiogram (ECG, hearth activity), Electrooculogram (EOG, ocular activity), Galvanic Skin Response (GSR, skin sweating), and so on. Such neurophysiological measures can be seen as the physical interface of the NEUROID technique that will enable to gather insights about all the aspects relating to HFs of the operator like Mental Workload, Stress, Vigilance, and Engagement. The key concept of NEUROID is the Human Performance Envelope (HPE) taxonomy: instead of considering one or two single human factors, the HPE investigates a set of interdependent factors, working alone or in combination, which allows to completely characterize the operator. In other words, these concepts are proposed as performance shaping factors, which can differentially and interactively affect successful completion of a task. The HPE theory explicitly declares that boundaries exist where performance can degrade in line with the theoretical underpinnings for the considered HFs.
Benefits
Traditional methods to catch information about the operators’ HFs are usually based on self-reports and interviews. However, it has been widely demonstrated how such kind of measures could suffer of poor resolution due to a high intra- and inter-user variability depending on the nature of the measure itself (i.e. subjective). In addition, the main limitation in using subjective and behavioural measures alone is due to the impossibility of quantifying ‘‘unconscious’’ phenomena and feelings underlying human behaviours, and most importantly it is not possible to measure such unconscious reactions experienced by operators while performing working activities. In fact, the execution of a task is generally interrupted to collect subjective evaluations.
On the contrary, neurophysiological measures exhibit an unobtrusive and implicit way to determine the operator’s affective and cognitive mental states on the basis of mind-body relations. Therefore, the benefit and advantage of the NEUROID technique is to use neurophysiological measures and machine-learning algorithms to overcome such limitations, especially to (1) objectively assess the operator’s mental states while dealing with operative tasks; (2) identify the most critical and complex conditions and correlated them with accident and incident investigations; and (3) create a closed-loop between the systems and operators (i.e. Joint Human Machine Cognitive system) to continuously and non-invasively monitor the operators themselves.
Finally, modern wearable technology can help in overcome the invasiveness (e.g. many cables, uncomfortable) of the equipment necessary to collect the neurophysiological signals from the operators.
How It Works
• NEUROID consists in 3 main phases as reported in the figure.
• The neurophysiological signals are gather from the operators by wearable technology while dealing with working tasks.
• Afterward, the neurophysiological data are processed through a series mathematical steps towards the machine-learning phase, in which each HF is classified.
• Finally, the considered HFs are combined to define the Operator’s HPE, and integrated with the operator’s behaviour, and data related to accidents and incidents (e.g. SHIELD database and HURID framework) for
a comprehensive operator’s assessment which can be employed for different applications, for example real-time mental states assessment, or triggering adaptive automations.
Illustrative Example
Aviation Domain
To see how the NEUROID technique can be implemented in practice we can consider the following scenario where an Air Traffic Controller (ATCO) is managing the air traffic and at the same time we are acquiring the ATCO’s EEG, ECG, and GSR neurophysiological signals. In the first phase of the scenario, the ATCO can rely on the support of high-automated systems to manage high traffic situation (High). Then, the traffic demand returns to a normal condition (Baseline), but at a certain moment the automations crash (Malfunction) and the ATCO will have to keep managing the traffic, and find out what is wrong with the automations.
In this context, we can use the NEUROID to measure how the ATCO’s HPE changes. In this regard, the neurophysiological data will be employed to estimate the ATCO’s Mental Workload, Stress, Attention, Vigilance, And Cognitive Control Behaviour based on the S-R-K model. Finally, those HFs will be combined to define the ATCO’s HPE on the three operational conditions as shown in the following figure. In particular, the values of the considered mental states have been normalized within the [0 ÷ 1] range: “0” means Low, while “1” mean High. Concerning the S-R-K aspect, “0” represent the S (Skill), “0.5” the R (Rule), and “1” the K (Knowledge) level.

The analysis of the HPE in the different scenario conditions exhibits interesting variations on the configuration of the mental states. In fact, the failure of the automations (red line) induced higher Vigilance, lower Attention, and shift from Skill to Rule level in the Cognitive Control Behaviour with respect to the HIGH (orange line) and BASELINE (blue line) conditions. Furthermore, considering the HPE changes over time throughout the ATM scenario allows to identify those moments, thus situations, corresponding to high (RICH) or low (POOR) performance. For example, for the considered ATCO, the HPE corresponding to RICH (green plot) and POOR (red plot) performance are reported in the following figure. Generally, in correspondence of RICH performance condition, the vigilance is higher and the stress is lower than during POOR performance. In conclusion, the NEUROID could be used, for example, to monitor the operators and warn them when they are working under low vigilance and high stress condition.

Maritime Domain
To see how the NEUROID technique can be implemented in Maritime practice we can consider the following scenario where the collision occurred between tanker ship and livestock ship during Dardanelle Strait passage at sea. The collision occurred during overtaking. The VTS (Vessel traffic services) was informed about the collision since it occurred during Dardanelle Strait passage. The weather was partly cloudy and sea state was calm at the time of collision. The time was early morning. The officer was keeping the navigational watch at the time of collision. It was early morning at the time of collision.
The HF analysis of the ship collision during Strait passage would highlight the following potential root causes:
• Mental Fatigue: Rather than physical fatigue, over alertness and overload (decision making, concentration, mental load). Watchkeeper Officers continuously working load can affect his/her decisions.
• Physical Fatigue: Rather than mental fatigue, physical fatigue can be seen due to intensive work load on-board ship.
• Inadequate Manning on Bridge: According to sailing zone, increase the number of watchmen on bridge may help perception of the dangers earlier.
• Inadequate Policy, Standards and Application: Increase of the inspections due to sailing rules and minimum CPA-TCPA values and activation of the existing rules may help avoiding dangerous situations and provide clearance from the plotted vessels.
• Inadequate / Lack of Communication: Necessary manoeuvre could not be applied due to inadequate communications between vessels. Lack of communications between vessels and VTS also caused vessels to sail in close range. Every communication methods on board must be managed in most efficient manner.
• Poor Risk Evaluation: Main reasons of the incident between vessels are the failure of the evaluation of risks for all vessels in the sailing area and unforeseen of the other vessel possible manoeuvres which were sailing in the outmost line of the separation.
• Inadequate Leadership and Supervision / Planning: Another root causes of the incident are improper planning of watch hours and not taking necessary measurements as a result of evaluations of inconveniences timely.
• External/Environmental Conditions: Sailing in narrow zone, congestion and poorness of the VTS stations in planning the traffic are the main effective reasons of the incident. To prevent such like incidents, environmental conditions must be evaluated sufficiently and proper speed and watch order must be planned according to congestion.
Some of those aspects are mainly linked to the management level (e.g. manoeuvres procedures, risk evaluation), but the ones coming from the evaluation of the operators’ status like the mental and physical fatigue can be monitored and measured via the NEUROID during the working activities.
In particular, along each phase of the considered scenario the neurophysiological measures can characterise the operators in terms of Mental Workload, Stress, Vigilance, and Engagement combination and those information can be consequently used to:
• interact and\or intervene in real-time on the system, for example depending on the Master's mental workload it could be possible to enable a warning during overload or low vigilance conditions to regain the proper operational status;
• post-doc analyse the incident\accident or simulation by combining the previous tasks analysis, and the operators' mental states profile along the scenario, for example to find out how the Mental Workload, Stress, Vigilance, and Engagement of the Master and C/O were right before the collision or during a specific phase which brought to the collision, and finally understand if the configuration of those mental states was not appropriate (e.g. distracted?) or, on the contrary, the operators were under too high demanding and stressing conditions due to the adopted procedure or situation.