A desensitization device includes an acquisition module for acquiring the current flight parameters of the aircraft, a generation module for generating a first image depicting flight symbology including at least one reference zero pitch line, a generation module for generating a second image depicting topography of terrain overflown by the aircraft, a generation module for generating a third image including at least two portions separated by a separating line, a generation module configured to generate a fourth image by superposing the first image, the second image and the third image in that order, the first image being placed in the foreground, and a transmission module configured to transmit, to a user device, a signal that is representative of the fourth image.