AIM Difficulties in neurocognition and social interaction are the most prominent causes of morbidity and long-term disability in children with neurofibromatosis type 1 (NF1). Symptoms of attention-deficit-hyperactivity disorder (ADHD) have also been extensively recognized in NF1. However, systematic evaluation of symptoms of autism spectrum disorder (ASD) in children with NF1 has been limited. METHODWe present a retrospective, cross-sectional study of the prevalence of symptoms of ASD and ADHD and their relationship in a consecutive series of 66 patients from our NF1 clinic. The Social Responsiveness Scale and the Vanderbilt ADHD Diagnostic Parent Rating Scale were used to assess symptoms of ASD and ADHD.RESULTS Sixty-six participants (42 males, 24 females) were included in this study. Mean age at assessment was 10 years 11 months (SD 5y 4mo). Forty percent of our NF1 sample had raised symptom levels reaching clinical significance on the Social Responsiveness Scale (T ‡ 60), and 14% reached levels consistent with those seen in children with ASDs (T ‡ 75). These raised levels were not explained by NF1 disease severity or externalizing ⁄ internalizing behavioral disorders. There was a statistically significant relationship between symptoms of ADHD and ASD (v 2 =9.11, df=1, p=0.003, /=0.56). Particularly salient were the relationships between attention and hyperactivity deficits, with impairments in social awareness and social motivation. INTERPRETATIONWe found that symptoms of ASD in our NF1 population were raised, consistent with previous reports. Further characterization of the specific ASD symptoms and their impact on daily function is fundamental to the development and implementation of effective interventions in this population, which will probably include a combination of medical and behavioral approaches.Neurocognitive and learning-related deficits in pediatric neurofibromatosis type 1 (NF1) are associated with the greatest level of disease morbidity. [1][2][3] In addition to neurocognitive deficits, extensively described elsewhere, 3,4 upwards of 50% of the population with NF1 meets DSM-IV-TR 5 diagnostic criteria for attention-deficit-hyperactivity disorder (ADHD), and the associated attention and executive function deficits are particularly problematical and functionally limiting in this population. [1][2][3]6 Such neurocognitive impairments are related to disruptions in academic functioning 1,7 and socialization. 4 It is well accepted that social deficits occur in individuals with NF1. 4,8,9 Barton and North reported that nearly 40% of their population with NF1 had social interaction problems in the borderline ⁄ clinical range. They also noted the significant role of comorbid ADHD in poor social outcomes. 4 In addition, associations between neurocognitive deficits commonly seen in NF1 and poor social functioning have been described.Huijbregts and de Sonneville showed that cognitive control (i.e. a combination of processing speed, working memory, inhibitory control, and emotional processing function...

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In the Neurofibromatosis type 1 (NF1) mouse model, lovastatin, used clinically for hypercholesterolemia, improves cognitive dysfunction. While such impairment has been studied in NF1, the neural substrates remain unclear. The aim of this imaging add-on to a phase-1 open-label trial was to examine the effect of lovastatin on Default Network (DN) resting state functional connectivity (RSFC). Seven children with NF1 (aged 11.9±2.2; 1 female) were treated with lovastatin once daily for 12 weeks. A 7-minute 3-Tesla echo-planar-imaging scan was collected one day before beginning treatment (off-drug) and the last day of treatment (on-drug) while performing a Flanker task. After regressing-out task-associated variance, we used the residual time series as “continuous resting-state data” for RSFC analyses using 11 DN regions of interest. For qualitative comparisons, we included a group of 19 typically developing children (TDC) collected elsewhere. In the on-drug condition, lovastatin increased long-range positive RSFC within DN core regions (i.e., anterior medial prefrontal cortex and posterior cingulate cortex, PCC). In addition, lovastatin produced less diffuse local RSFC in the dorsomedial prefrontal cortex and PCC. The pattern of RSFC observed in the NF1 participants when on-drug closely resembled the RSFC patterns exhibited by the TDC. Lovastatin administration in this open trial regulated anterior-posterior long-range and local RSFC within the DN. These preliminary results are consistent with a role for lovastatin in normalization of developmental processes and with apparent benefits in a mouse NF1 model.

Objective: This study investigated psychological influences on drug withdrawal symptomatology using a caffeine-based model. Methods:Using the 2 × 2 balanced placebo design caffeine dose (given caffeinated vs decaffeinated coffee) was crossed with dose expectancy (told caffeine vs. decaf) among 87 (16-hr abstinent) regular coffee consumers in a 2-day study.Results: There were effects of expectancy and pharmacology that differed depending on the measure. Those told decaf reported greater caffeine cravings than those told caffeine 45 min and 8 hr postmanipulation. There were no expectancy effects on withdrawal symptoms or cognitive performance. There were pharmacological effects on all measures. Those given decaf reported greater withdrawal symptoms and showed poorer cognitive performance 45 min and 8 hr postmanipulation, with effects for headache and flu-like symptoms first emerging 8 hr postmanipulation (i.e., 24 hr abstinence in given decaf conditions). Caffeine readministration alleviated all withdrawal symptoms and cognitive decrements within 45 min. No drug by expectancy interactions were observed. Conclusions: These findings confirm a strong pharmacological basis for caffeine withdrawal and an important role of cognition in drug craving. Future research should investigate the role of expectancy in drug withdrawal and craving and the potential use of expectancy manipulations in symptom prevention and management. KEYWORDS balanced placebo design, caffeine, drug withdrawal, expectancy, nocebo effect

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