Bretigny Sur Orge

Many jobs require high attentional performances that are maintained over time, which imply safety issues. Just like physicial performances of top athletes, it is possible to use a set of innovative methods and technologies to improve cognitive performances (attention, working memory, decision making… ), in particular with the help of brain training programs such as neurofeedback protocoles. Although neurofeedback training efficiency has been evaluated in many context (either with patients or healthy subjects), it is still a subject of debate. More specifically, inter-individual variability is far from beeing understood. We hypothesize 1) that an electroencephalographic (EEG) based neurofeedback training may improve attentional performances of healthy subjects, and 2) inter-individual variability might be explained by factors such as body awarness, sleep parameters and genetics of individuals. 1. To demonstrate the efficiency of EEG neurofeedback (EEG-NFB) trainings versus a control group, we will compare the conflict monitoring score obtained with the Attentional Network Task (Reaction Times (RT) in ms of Incongruent trials minus Reaction Times of Congruent trials : RTincongruent - Rtcongruent). Our hypothesis is a reduction of the conflict monitoring scores after the EEG-NFB compared to baseline (before EEG-NFB), and a lower score for the EEG-NFB group compared to the control group. 2. To describe the different factors influencing EEG-NFB training efficacy, we will explore the inter-individual variability by assessing the body awarness (especially cardiac interoceptive accuracy with a counting task), sleep parameters (hypnogram, sleep power spectral activities) and genetic polymorphisms (DRD2, COMT, DAT1, PER3, ADA, ADORA2A, TNF-α). The study design will be a controlled interventional protocol, double-blinded with parralel-arms (EEG-NFB vs Control) in healthy volunteers. * Prior informations will be given to individuals expressing an interest in this study. * During the inclusion, an investigator or a member of the research team will verbally reiterate the informations and answer any additional questions. The volunteer will be reminded of his/her rights in the contexte of research involving the human person. * After verifying volunteer's eligibility criteria, he/she will be asked to sign the consent form. * Volunteers will have to fill out a sleep questionnaire.Sleep/wake cycles will be home monitored with a wearable headset during 14 days : 7 days before the start of EEG-NFB training, and 7 during the EEG-NFB training. * Cognitive tests will be done each day of EEG-NFB training (or control) : Psychomotor Vigilance Task, Attentional Network Test, AX-Continuous Performance Test and a Heartbit Counting task. The cognitive test period will last 30 minutes. * EEG-NFB training (or control) will be done for 5 consecutive days, each session lasts 35 min (10 blocs of 3 min, and short breaks of 30 s). Each session will be precedeed and followed by a resting-state recording. The control group will perform a SHAM EEG-NFB. * Before the first session and after the last (5th) session, cortisol and α-amylase concentrations will be evaluated by saliva tests. * Before the session and after the last session, questionnaires evaluating body awarness will be filled out by volunteers.

The EXPLO-MITO study is an ancillary study from the main EXPLO-CCE study (NCT04593316; IDRCB: 2020-A01967-32). The Heat Tolerance Test (HTT) is a physiological exploration that has several advantages for use in research and clinical settings. Unlike the walk-run test, it is performed under controlled conditions, both environmentally (temperature control, humidity, etc.) and in terms of effort intensity. In addition, there are published interpretation criteria for this test allowing to characterize thermoregulation profiles and to distinguish between Heat Intolerant (HI) and Heat Tolerant (HT) patients. The reproducibility of this test and its performance in a climatic chamber allows a true comparison of thermophysiological responses (heart rate, rectal and skin temperatures, skin blood flow and sweat loss), which was not possible with the run-walk test, which was more a field test validating a physical aptitude for recovery (so-called "occupational" test) than a physiological exploration evaluating a response to stress by comparing it with the expected response in a population of young, healthy, properly trained subjects. Moreover, the HTT is a much less physiologically demanding test than the 8-km run. The HTT, which corresponds to a 2-hour walk at 5 km/h with a 2% slope at 40°C and 40% relative humidity, is a so-called "compensable" thermal stress; that is, under these conditions of exercise and environment, when the individual has normal thermoregulatory capacities, a thermal equilibrium plateau is reached during the second hour, when the individual's thermolysis capacities make it possible to compensate for the production of heat by the exercise and the gain of heat related to the environment. On average, this plateau is between 38° and 39°C. This is clearly not the case with our experience of physiological monitoring of the 8-km walk-run which rarely allows a temperature plateau to be reached and is accompanied by a temperature rise constantly above 39°C. In addition to being performed in the laboratory, this test is therefore completely safe. For all these reasons (reproducibility, relevance, predictive value of recurrence), this test has been used for more than 30 years by the Israeli army for the assessment of these cases of exercise heat stroke before their return to work. There is therefore a fair amount of published data and hindsight on the use and interest of this test. The Israeli test has the highest level of recommendation (Grade A) of all the other published heat tolerance tests. Also, the availability of a climatic chamber means that this test can now be proposed as one of the explorations available to clinicians who have to decide on the fitness of soldiers after exercise heat stroke.