Functional Connectivity of the Interoceptive Network in RLS

Summary

Restless Legs Syndrome (RLS) is a sensorimotor disorder primarily characterized by an irresistible urge to move the legs while at rest. A key hypothesis suggests that RLS symptoms are linked to abnormal brain function in processing internally generated stimuli, particularly interoception. This distorted perception of the internal bodily state leads to maladaptive behaviors, which may manifest across a wide range of medical and psychiatric disorders. Here, the investigators hypothesize that dysfunction in the insular cortex (IC) may result in a failure of behavioral adaptation, primarily expressed as an urge to move the legs and hyperarousal, even when the body and mind need rest. This project aims to assess the relationship between interoceptive abilities and diurnal fluctuations in IC functional connectivity (FC) in patients with RLS compared to healthy controls. The investigators will also examine correlations between the FC of the interoceptive network, measured in the morning and evening on the same day, using multilayer network analysis, daily fluctuations in RLS symptom severity, and objective measurements of the sleep/wake cycle, gathered through a two-week ambulatory assessment using mobile technologies such as Ecological Momentary Assessment (EMA) and actigraphy, along with scores from self-reported questionnaires. The findings may provide strong evidence to support or refute the hypothesis of interoceptive dysfunction in RLS patients.

Conditions

• Restless Legs Syndrome

Interventions

OTHER

Clinical assessment

RLS history, RLS treatments, and International Restless Legs Syndrome Rating Scale (IRLSRS) will be recorded

BEHAVIORAL

auto-questionnaires (PSQI, ISI, ESS and HADS)

To evaluate sleep quality, daytime somnolence and mood disorders (Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS) and Hospital Anxiety and Depression Scale (HADS)).

DEVICE

Ecological Momentary Assessment (EMA)

4 electronic interviews administered per day during 14 days by a study-dedicated Android OS smartphone

DEVICE

activity-rest cycle

To further investigate the mutual influence of sleep quality on RLS symptoms and mood, the activity-rest cycle will be monitored by wearable actigraph to be placed on the non-dominant wrist during a period of 13 days and 14 nights.

BEHAVIORAL

auto-questionnaires (ASRS, PSAS, APS, MAIA-2)

Interoceptive awareness and accuracy estimation : Adult ADHD Self-Report Scale (ASRS), Pre-Sleep Arousal Scale (PSAS), Arousal Predisposition Scale (APS) et Multidimensional Assessment of Interoceptive Awareness version 2 (MAIA-2)

DEVICE

MRI

Morning and evening functional brain imaging

Sponsors & Collaborators

• Restless Legs Syndrome Foundation

  collaborator UNKNOWN

• University Hospital, Bordeaux

  lead OTHER

Principal Investigators

• Imad Marc Antoine GHORAYEB, MD, PhD · University Hospital, Bordeaux

• Gwénaëlle CATHELINE, PhD · Université de Bordeaux - INCIA

Study Design

Allocation

NON_RANDOMIZED

Purpose

OTHER

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

70 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-09-16

Primary Completion

2026-10-31

Completion

2026-10-31

Countries

• France

Study Locations