To date, neuropsychological assessment of deaf signing persons is complicated by a lack of resources, especially the absence of tools available in French Sign Language (LSF). This is due to perceptual and cultural differences, and in particular the linguistic differences between French and LSF.

This lack of resources significantly hinders access to care for deaf patients, as neuropsychological assessment is often a key clinical criterion in the diagnosis of certain neurological pathologies (Alzheimer's disease in particular) and enables coherent care plans to be drawn up, for example in the aftermath of strokes or traumatic brain injuries.

In particular, episodic memory (which refers to the ability to memorise information anchored in a specific context) is a cognitive domain that is sensitive to pathologies such as Alzheimer's disease, but it is not currently possible to assess it with deaf signing patients.

The aim of this study is to create a memory assessment test adapted to a deaf population that expresses in LSF and to normalize this test on this same population.

The aim is to provide a diagnosis assessment tool, which currently does not exist in France, to improve access to care for deaf people. This project could then be extended to the creation of tests for other cognitive domains (executive functions, attention, social cognition, etc.) and to prospects for cognitive remediation.

The 16-item Free and Cued Recall test (RL-RI 16) is the best choice because it is easy to use and accurate enough to assess each stage of episodic memory. These qualities make it a decisive tool in certain differential diagnosis.

In order to select the most relevant signs, lexical lists by frequency in LSF will be drawn up during a preliminary phase, during which the participants will have to give, in one minute, the maximum number of signs belonging to different categories (animals, vegetables, clothes...). These lists will be used to select the most relevant signs according to their frequency (neither too common nor too rare), based on the same principle as RL-RI 16.

It will then be standardised on deaf adults, for whom LSF is the main language, with no cognitive impairment, across France, via the various Deaf Care Units, with the help of French / LSF interpreters. Working with different centers in France will make it possible to recruit a larger and more representative number of participants, and to be more sensitive to any regional effects.

Inclusion Criteria:

• Person aged ≥ 18 yo
• with severe or profound deafness (hearing loss ≥ 70 decibels)
• whose main language is French Sign Language
• able to consent in writing after a clear explanation of the procedure
• affiliated to the French Healthcare system (Sécurité Sociale) through self or another person

Non-inclusion criteria:

• person with a medical history in neurology (stroke, traumatic brain injury, dementia) or psychiatry bipolar syndrom or schizophrenia that would not be medicated, severe depression)
• persons with medical developmental backgroung (e.g genetic syndrome)
• person with cancer history needing chemotherapy
• person with a diagnosed and untreated sleeping trouble
• person drinking > 10 glasses of alcohol per week or using drugs on a daily basis
• person with visual issues
• person under 18yo or unable to take decisions for self

Exclusion Criteria:

A score ≤ 20/28 or 17/28 at the MMS-LS test, depending on the schooling of the participant (20/28 for participants with a degree, 17/28 for participants without a degree)