Emotions play a crucial part in the quality of life, interpersonal relationships and mental health in general. In adults presenting with intellectual developmental disorder (IDD), emotional abilities may be hindered, thus leading to more challenging behaviors. A better understanding of emotional processes of adults with IDD may help improve the efficiency of behavioral interventions and better improve their quality of life.

The primary goal of this study is to better characterize the abilities and weaknesses of adults with IDD concerning their emotional processes, in comparison to a healthy population. The secondary goals are :

• to determine if these difficulties are underlined by oculomotor and attention (auditory and visual) processes
• to determine if behavioral difficulties, as reported by the families of adults with IDD, are underlined by specific difficulties in facial emotion recognition, emotion identification in context and/or identification of vocal emotions.

The study will be carried out in 3 steps :

Step 1: All participants will undergo tests to evaluate their intellectual abilities, and auditory and visual screening tests.

Step 2 : All participants will undergo neuropsychological tests assessing attentional and oculomotor abilities (1 hour). During this time, the participant's family member will complete the questionnaires assessing behavior.

Step 3 : All participants will undergo the experimental ACQUISS protocol (task 1 : faces; task 2 : faces in context; task 3 : prosody) (1 hour).

Detailed Description:

Step 1 :

During this first step, all participants (both groups), will undergo the Raven Progressive Matrices (John and Raven 2003) to assess their intellectual abilities. They will then undergo an auditory screening test (tonality test) and a visual screening task (the Rossano-Weiss scale and the Palettes de Léa Grattins task).

Step 2 :

During this second step, all participants (both groups) will undergo :

1. - the tangled lines test (Rey, 1964) : in this task, the participant must follow by gaze entangled lines to determine the beginning and end of each line.

2. - the NSUCO oculomotor test (Maillet, 2015) : the orthoptist will evaluate the ability of the participant to carry out ocular saccades and movement pursuit.

3. - the Auditory attention task of the NEPSY-II battery (Korkman et al., 2012)

4. - 2 cancellation tests from the EVA battery (Chokron, 2010):

   • the TeddyBear Cancellation test
   • the single-letter cancellation test

Step 3:

During this step, all participants from both groups will undergo the ACQUISS protocol.

Inclusion Criteria:

IDD group :

• Diagnosis of IDD according to DSM-V criteria
• aged between 18 and 3 years
• French speaking
• Membership or entitlement to a social security plan
• informed consent, or that of the tutor, to take part in the study
• presence of a caregiver to complete the questionnaires at V2.

Control group :

• aged between 18 and 35 years
• French speaking
• Membership or entitlement to a social security plan
• Informed written consent to take part in the study.

Exclusion Criteria:

IDD group :

• visual or auditory impairments, evaluated at V1
• non stabilized epilepsy
• undergoing treatments that can impact brain or psychological functioning
• major motor disorders
• breastfeeding or pregnant woman

Control group :

• neurodevelopmental or psychiatric disorder
• history of brain trauma (TBI, stroke, etc…) or non-stabilized epilepsy
• visual or auditory impairments, evaluated at V1
• non stabilized epilepsy
• undergoing treatments that can impact brain or psychological functioning
• major motor disorders
• breastfeeding or pregnant woman