Relationship Between Breathing and Attention in Children With Ondine Syndrome

Congenital central hypoventilation syndrome (CCHS) is a rare genetic disorder caused by PHOX2B gene mutations. CCHS is characterized by hypoventilation and autonomic nervous system dysregulation and global dysautonomia necessitating artificial ventilation. CCHS increases the risk to develop neurocognitive deficiencies. Patients retain ventilatory activity when awake through a respiratory-related cortical network but the need to mobilise cortical resources to breathe lead to breathing-cognition interferences during cognitive tasks.

No study has focused on attentional abilities in CCHS pediatric population to highlight a specific attentional profile or to investigate the double task paradigm impact when attentional resources and management of spontaneous breathing are competing.

The aim of this study is to (i) Understand the link between spontaneous breathing and attentional functioning in CCHS children by comparing the evolution of breathing pattern relatively to the complexity of the attentionals tasks.

(ii) Characterize the attentional profil of CCHS patients by comparing attentional tasks performance of CCHS children versus control children (iii) Measure the impact of variables such as age and CO2 ventilatory response on attentional performances, by comparing attentional performances of the young patient group (< 50e p) to the attentional performances of older patient group (> 50e p) and studying the correlation between ventilatory response to CO2 and attentional performance (iv) Investigate the link between clinicals and behavioural tools regarding attentional and executive domains by studying the correlation between the cognitif test and inventories results Hypothese : attentional task could be link to a deficit in breathing function leading to hypoxemia and hypercapnia (alveolar hypoventilation).

Methode : compare CCHS patients performances and control group in neuropsychological tests used usually in clinical practice (TEA-ch, NEPSY, BRIEF) and research (Conners 3, K-CPT II or CPT III, Flankers Task).

Twenty children (age range : 6 to 16 years old) with CCHS and IQ > 70 and twenty control subjects in the same age range without neurodevelopmental disorder diagnosis will be enrolled.

Firstly, subjects of both groups will respond to a neuropsychological assessment including intellectual Wechsler scale (WISC V), instruction comprehension test (Nepsy II), a manual laterality test and attentional and executive assessment (TEA-ch + NEPSY II).

Secondarily, CCHS group assessment will be completed with a double task paradigm. Our protocol includes a simple task condition (the patient must remain still) and a double task condition (the patient respond to the flanker tasks and K-CPT II or CPT III).

Procedure : continuous recording of breathing parameters : oxygen saturation, exhaled PCO2 (PETCO2 with nasal cannula) and respiratory rate. Breathing respiratory parameters will be recorded during simple condition and double task condition. "