Autobiographical Memory, Future Thought, and Eye Movements in Huntington's Disease

It will be assessed using the TEMPau specificity scale. This scale uses a Likert scale ranging from 0 to 4 points (0: no response or general information; 1: vague event without spatial-temporal context; 2: generic or specific event without spatial-temporal context; 3: specific event in a non-detailed spatial-temporal context; 4: specific event in a detailed spatial-temporal context). This scale allows two main scores to be collected for each period of life explored: 1) an overall autobiographical memory score counting all events, regardless of their nature (max.: 3 x 1 = 3) and 2) a strictly episodic score, counting only memories that meet all the criteria for episodicity, rated 4 (max.: 3 x 4 = 12). The scale also provides: 1) an overall autobiographical memory score for all four life periods explored (max.: 3 x 4 = 12) and an overall strictly episodic score, counting only memories that meet all the criteria for episodicity across all four periods, rated 4 (max.: 12 x 4 = 48).

self-questionnaire comprising eight items, measured on a Likert scale ranging from 1 to 4 points (1: no, that is completely untrue; 2: no, that is rather untrue; 3: yes, that is rather true; 4: yes, that is completely true). The 8 items are as follows: 1: I felt like I was reliving the original event; 2: I felt like I was travelling back in time to the moment when the event happened; 3: I don't just know that this event happened, I remember actually experiencing it; 4: I believe that the event in my memory actually happened as I remember it; 5: I can see and hear elements of the event in my mind; 6: I can now feel the emotions I felt when the event happened; 7: I can remember where the event took place; I can remember the time when the event occurred. This scale allows a phenomenological score to be obtained for each period of life explored (max.: 3 x 8 x 4 = 96) and an overall phenomenological score for all four periods of life explored (max.: 3 x 8 x 4 x 4 = 380).

Each memory is evaluated according to six empirically based dimensions:

• the specificity of the event (rated from 0 to 4 according to TEMPau criteria, with 0 = extended or semantic memory, 4 = unique event, situated in time and space),
• identity relevance ('This memory reflects an important part of who I am')
• the presence of a lasting personal conflict or theme ('This memory is linked to an important theme or conflict in my life')
• emotional intensity ('This memory expresses a very strong or striking emotion')
• reflective integration ('This memory has helped me learn a personal lesson')
• frequency of mental access ('This is a memory I often think back on or talk about regularly')

The last five dimensions are assessed by self-questionnaire, on a Likert scale ranging from 1 to 4 (1 = not at all, 4 = completely). This combination gives an overall SDM score ranging from 5 (weakly self-defined memory) to 24.

It will be assessed using the 'Then' and 'Now' scale, which consists of asking the subject to evaluate (self-questionnaire), for each memory, on a Likert scale ranging from -3 to 3, how they felt at the time the event occurred and how they feel when they recall it.

It will be assessed qualitatively using the definitions provided by Blagov and Singer (2004):

• Integrative memories: There is a shift away from narrative events and descriptions to make an additional statement about the importance or significance of the memory to the individual. A meaningful statement must go beyond simply saying that the memory is 'important', 'the most painful' or 'a memory I will never forget'. There must be an indication of why the memory is important and moving.
• Non-integrative memories: These are discussed in the manual and do not meet the requirements of integrative memories.

Measured in millimeters (between 1.5 to 8 mm) with Pupil Labs Core monocular device

number of fixation and saccades measured with Pupil Labs Core monocular device

duration of fixation and saccades measured with Pupil Labs Core monocular device

assessed using the ZTPI-short (Zimbardo Time Perspective Inventory - short version)

identity fluency task: through spontaneous verbal productions

It will be assessed using the TALE-15 (Thinking About Life Experiences) questionnaire

using Unified Huntington's Disease Rating Scale; This scale is divided into several subscales grouping together different tests assessing: motor difficulties (dysarthria, dystonia, choreic movements, bradykinesia, gait disorders, etc.), cognitive difficulties [flexibility (literal verbal fluency), processing speed (Symbol Digit Modalities Test), inhibition (Stroop task)], level of independence, and functional difficulties. The TFC (Total Functional Capacity) is a specific subscale of the UHDRS that assesses patients' functional independence. It takes into account five areas: occupational capacity, financial management, domestic management, independence in activities of daily living, and degree of care required. The overall score ranges from 0 (complete dependence) to 13 (complete independence). A high score indicates preserved independence, while a low score reflects a significant loss of independence. TFC is a benchmark indicator of disease severity and progression.

overall efficiency measured using Mini Mental Scale examination

flexibility measured using categorical fluency

flexibility measured using Trail making Test

Behaviour troubles measured with Problem Behaviours Assesment scale