Sleep and Psychosocial Characteristics of Children with Narcolepsy According to Their Intellectual Profile: A Case-Control Study.

Adequate intellectual abilities are a protective factor for psychosocial adjustments in chronic disorders. The main objective of this study was to assess the cognitive abilities, sleep, and psychosocial characteristics of children with narcolepsy compared to controls, according to their intellectual profile. Children underwent a polysomnography, completed an intellectual ability assessment, and filled out standardized questionnaires. The group with an intelligence quotient (IQ) in the area of high intellectual potential (high IQ, HIQ) consisted of 25 children with narcolepsy (HIQ-N, 40% boys, median age 11.5 years, 48% with obesity, 60% under treatment) and 25 controls (HIQ-C, 68% boys, median age 11.7 years). Compared to HIQ-C, HIQ-N had a lower perceptual reasoning index and fewer conduct disorders. The group with an IQ in the normal range (NIQ) consisted of 22 children with narcolepsy (NIQ-N, 55% boys, median age 12.1 years, 59% with obesity, 64% under treatment) and 21 controls (NIQ-C, 68% boys, median age 10 years). NIQ-N presented the same intellectual profile as NIQ-C but reported more school difficulties. In children with HIQ, those with narcolepsy appear to have a different cognitive profile than controls. NIQ seems to predict a greater impact of narcolepsy on daily-life functioning.

Intellectual Abilities of Children with Narcolepsy.

High cognitive functioning could be a protective factor for school difficulties, behavioral and mood impairments in children with narcolepsy. To investigate this factor, we studied the intellectual abilities of 74 children with narcolepsy (43 boys, 11.7 years old at diagnosis, 91% of cataplexies, 64% obese, 100% HLA positive for DR-DQB1*06:02). All children underwent a one-night polysomnography followed by Multiple Sleep Latency Tests, an evaluation of intelligence quotient (IQ), and filled standardized questionnaires. Thirty-eight percent had high potentialities (HP defined by IQ > 130) and 48% had school difficulties. Using non-parametric tests, we found that HP children reported less difficulties at school and tended to have less impulsivity, conduct, and learning disorders than those without HP. They also tended to be less obese and had less desaturation. Using a multivariate regression analysis, we found an association between the REM sleep percentage and the IQ. REM sleep could be involved in the dynamic changes contributing to the equilibrium of intellectual functioning. This study highlights that despite their frequent school difficulties, narcolepsy per se is unlikely to be a cause of intellectual disability in children. Prompt diagnosis and management of comorbidities such as obesity and obstructive sleep apnea (OSA) could improve cognitive and school performances in these children.

A combined forced-attention dichotic listening - Go/Nogo task to assess response inhibition and interference suppression: An auditory event-related potential investigation.

OBJECTIVE: Interference suppression and response inhibition are distinct effortful inhibitory processes. Yet they rely on partly overlapping neural substrates. Their independence was studied using an auditory paradigm. METHOD: Continuous EEG was recorded in 16 adults and event-related potentials (ERPs) were analyzed in a new dichotic listening - Go/Nogo task. Attention was directed either to the right dominant ear (forced-right blocks [FR]) or to the left ear (forced-left blocks [FL]). The Go/Nogo task required a motor response only to the standard word played to the selected ear; the nonselected ear was simultaneously presented with the same word (Go condition) or with a deviant (Incongruent Go condition). In the Nogo condition, a deviant was presented to the selected ear while the standard was played to the nonselected ear. Effortful interference suppression was expected only in the FL blocks to override the automatic processing of distractors in the dominant ear. RESULTS: When no effortful interference suppression was necessary (FR blocks) in the Nogo condition, the N2 and P3 increase probably reflected two subcomponents of response inhibition (response restraint and response cancellation) and the P2 decrease probably reflected an early inhibitory mechanism (sensory gating). When effortful interference suppression was necessary (FL blocks), there was no Nogo-N2 (i.e., no response restraint). Interference suppression (Incongruent Go condition minus Go condition) also increased the N2 and P3, but did not modulate the P2. CONCLUSIONS: This new paradigm confirms the partial overlap between response inhibition and effortful interference suppression and points out specific features of their subcomponents. (PsycINFO Database Record (c) 2019 APA, all rights reserved).