Exploration Strategies in Night Vision Sensors

The main objective of this clinical trial is to identify a variation in visual strategy characterized by both head movements and eye movements of healthy volunteers during a target detection task when images simulating night vision goggles (NVG) are presented, compared to a situation in which the images simulate a natural environment.

To highlight changes in environmental scanning with simulated images from NVG, objective measurements will be collected:

* eye movements characterized by saccades (speed, latency, and number) for each stimulus * head movements (horizontal angle of the participant's head) for each stimulus and throughout the exposure

Participants sit facing a screen (9.90 m x 2.10 m) onto which a virtual scene is projected. The objective is to correctly identify, as quickly as possible, a target stimulus (represented by a tank) that may appear in the scene. They must use the directional arrows on a game controller to indicate whether the tank is moving to the left or to the right.

There are four visits involving four viewing conditions in which the task remains the same:

* With restricted field of view and a normal scene. * Without restricted field of view and a scene simulating the vision obtained by NVGs. * With restricted field of view and a scene simulating the vision obtained by NVGs. * Without restricted field of view and a normal scene. Regarding the content of the scene, half of the tests in each visit involve a so-called poor scene when fog is simulated, or an enriched scene when there is no fog. Each visit lasts approximately one hour and thirty minutes.