Behavioral style of young boys with fragile X syndrome

To study the behavioral style or temperament of 45 boys, aged 47 to 88 mont hs, with full-mutation fragile X syndrome (FXS), 102 parent ratings on the Behavioral Style Questionnaire (MeDevitt and Carey 1978) were recorded. The se ratings were analysed with a variety of statistical techniques. Consider able variability was evident in temperament profiles; consequently, a chara cteristic profile was not identified for FXS. Boys with FXS differed signif icantly from the reference sample on five of nine temperament dimensions. T hey were more active and less intense, approachable, adaptable, and persist ent. No significant differences were found in distractibility, rhythmicity, mood, or sensory threshold. Only 16 of the 45 boys in the sample could be classified as easy, difficult, or slow to warm up. There was no link betwee n severity of developmental disability and temperament ratings. This suppor ts the theory that intelligence and temperament are separate constructs. Sc ores on temperament dimensions were stable over time. Our results suggest t hat many of the behaviors observed in boys with FXS may be related to tempe rament. Consequently, parent counseling and environmental modifications sho uld be considered as first line treatment. The question of whether the beha vior problems observed in boys with FXS are innate or whether they result f rom poorness of fit between child and environment is an important issue tha t needs further study.