Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA.
J Intellect Disabil Res. 2010 Mar;54(3):246-65. doi: 10.1111/j.1365-2788.2010.01255.x. Epub 2010 Feb 8.
Approximately one-quarter of individuals with fragile X syndrome (FXS) meet diagnostic criteria for autism; however, it is unclear whether individuals with comorbid FXS and autism are simply more severely affected than their peers with only FXS or whether they have qualitatively different profiles of behavioural impairments. To address this issue, variation in the FXS linguistic phenotype was examined in males with FXS with and without autism. The syndrome-specificity of the expressive language impairment of both groups of those with FXS was assessed in relation to Down syndrome. The extent to which different language sampling contexts affected expressive language in each diagnostic group was also examined.
Spontaneous language samples were collected from male adolescents with FXS without autism (n = 20), comorbid FXS and autism (n = 8), and Down syndrome (n = 16). Syntactic complexity (indexed by mean length of utterance), expressive vocabulary (indexed by lexical diversity), talkativeness, fluency and intelligibility were assessed in two contexts: conversation and narration. Groups were matched on non-verbal IQ, non-verbal mental age and chronological age to allow the assessment of relative strengths and weaknesses across language variables.
Males with comorbid FXS and autism were less intelligible than males with only FXS; no other differences between these two groups were found. Participants' performance differed across contexts for syntactic complexity, lexical diversity, talkativeness and fluency.
These findings contribute to existing research on the behavioural profiles of individuals with FXS or FXS with autism who have low cognitive abilities. Although individuals with comorbid FXS and autism may be, as a group, more impaired than those with only FXS, data from this small sample of males with comorbid FXS and autism with low IQs suggest that their relative strengths and weaknesses in spontaneous expressive language are largely comparable and not differentially affected by the context in which their talk occurs.
大约四分之一的脆性 X 综合征 (FXS) 患者符合自闭症的诊断标准；然而，目前尚不清楚患有合并 FXS 和自闭症的个体仅仅是比仅患有 FXS 的同龄人受到更严重的影响，还是他们在行为障碍方面具有定性上不同的特征。为了解决这个问题，研究人员检查了患有 FXS 且伴有或不伴有自闭症的男性个体中 FXS 的语言表型变化。评估了这两组 FXS 患者的表达性语言障碍与唐氏综合征的关系，以确定 FXS 特异性。还研究了不同的语言取样环境对每个诊断组的表达性语言的影响程度。
从无自闭症的 FXS 男性青少年（n = 20）、合并 FXS 和自闭症的男性青少年（n = 8）和唐氏综合征男性青少年（n = 16）中收集自发语言样本。在两种情况下评估句法复杂性（以平均话语长度表示）、表达性词汇量（以词汇多样性表示）、健谈程度、流畅性和可理解性：对话和叙述。通过非言语智商、非言语心理年龄和实际年龄对各组进行匹配，以评估语言变量方面的相对优势和劣势。
患有合并 FXS 和自闭症的男性青少年的可理解性低于仅患有 FXS 的男性青少年；在这两组之间没有发现其他差异。参与者在句法复杂性、词汇多样性、健谈程度和流畅性方面的表现因情境而异。
这些发现为具有低认知能力的 FXS 或合并 FXS 和自闭症的个体的行为特征的现有研究做出了贡献。尽管患有合并 FXS 和自闭症的个体作为一个群体可能比仅患有 FXS 的个体受到更大的影响，但来自智商较低的合并 FXS 和自闭症男性青少年的小样本数据表明，他们在自发表达性语言方面的相对优势和劣势在很大程度上是可比的，并且不受其谈话发生的情境的影响。
