The modulation of repetition effects by the lag between first and second presentations of a visual object during a speeded semantic judgment task was examined using both scalp event-related potentials (ERPs) and event-related functional magnetic resonance imaging (efMRI). Four levels of lag were used within a single session, from zero to one, to tens of intervening stimuli, and which allowed partial separation of the effects of interference from the effects of time. Reaction times (RTs) showed that the magnitude of repetition priming decreased as lag increased. The ERP data showed two distinct effects of repetition, one between 150 and 300 ms post stimulus and another between 400 and 600 ms. The magnitude of both effects, particularly the earlier one, decreased as lag increased. The fMRI data showed a decrease in the haemodynamic response associated with repetition in several inferior occipitotemporal regions, the magnitude of which also typically decreased as lag increased. In general, and contrary to expectations, lag appeared to have mainly quantitative effects on the three types of dependent variable: there was little evidence for qualitative differences in the neural correlates of repetition effects at different lags.

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Background X-linked hypophosphatemia (XLH) is a rare, genetic phosphate-wasting disease resulting in bone, muscular and dental problems, beginning in childhood and increasing in adulthood. This qualitative analysis aimed to explore patient-reported symptoms, complications and experiences of XLH over the life-course, using data from a large multinational online survey. Methods Responses to two open-ended questions from 209 adults and 86 children/adolescents (proxy report) with self-reported XLH were analyzed in eight age groups. Two researchers independently coded and analyzed the responses, using thematic analysis, with differences settled among a multi-disciplinary group. Six themes were identified, with age sub-group analysis conducted on the three most common, according to coding frequency. Results Within theme 1, ‘Clinical Signs and Symptoms of XLH’, ‘Pain’ was a dominant sub-theme across the life-course, but ‘Skeletal Pathology’ dominated the responses of children/adolescents. Within theme 2, ‘Impacts of Clinical Signs and Symptoms’, interference with ‘Physical Exertion’ and ‘Emotional Wellbeing’ (comprising depression/anxiety in adults and lack of self-esteem in children/adolescents) was reported across all ages. For theme 3, ‘Negative Treatment Experiences’, ‘Medication’ was problematic for children, with adults reporting lack of ‘Access to Appropriate Treatment’. Three further themes were identified: ‘Resilience’, ‘Positive Treatment Experiences’, and ‘Information Needs.’ Conclusion The multiple burdens imposed on people with XLH throughout their lifetime encompassed the physical, emotional and social, although the most challenging symptoms or complications differed between ages. Burden was further exacerbated by adult’s lack of access to appropriate treatment, illustrating the need for age-appropriate multidisciplinary care.

Purpose To describe the burden of musculoskeletal features and associated surgeries across the lifespan of adults with X-linked hypophosphatemia (XLH). Methods Three groups of adults were analyzed: subjects of a clinical trial, participants in an online survey, and a subgroup of the online survey participants considered comparable to the clinical trial subjects (according to Brief Pain Inventory worst pain scores of ≥4). In each group, the adults were categorized by age: 18–29, 30–39, 40–49, 50–59, and ≥60 years old. Rates of five prespecified musculoskeletal features and associated surgeries were investigated across these age bands for the three groups. Results Data from 336 adults were analyzed. In all three groups, 43–47% had a history of fracture, with the proportions increasing with age. The overall prevalence of osteoarthritis was >50% in all three groups, with a rate of 23–37% in the 18–29-year-old group, increasing with age. Similar patterns were observed for osteophytes and enthesopathy. Hip and knee arthroplasty was reported even in adults in their 30s. Spinal stenosis was present at a low prevalence, increasing with age. The proportion of adults with ≥2 musculoskeletal features was 59.1%, 55.0%, and 61.3% in the clinical trial group, survey group, and survey pain subgroup, respectively. Conclusions This analysis confirmed high rates of multiple musculoskeletal features beginning as early as age 20 years among adults with XLH and gradually accumulating with age.