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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The prevalence, in children aged under 15, of severe impairments of social interaction, language abnormalities, and repetitive stereotyped behaviors was investigated in an area of London. A "socially impaired" group (more than half of whom were severely retarded) and a comparison group of "sociable severely mentally retarded" children were identified. Mutism or echolalia, and repetitive stereotyped behaviors were found in almost all the socially impaired children, but to a less marked extent in a minority of the sociable severely retarded. Certain organic conditions were found more often in the socially impaired group. A subgroup with a history of Kanner's early childhood autism could be identified reliably but shared many abnormalities with other socially impaired children. The relationships between mental retardation, typical autism, and other conditions involving social impairment were discussed, and a system of classification based on quality of social interaction was considered.
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PMID:Severe impairments of social interaction and associated abnormalities in children: epidemiology and classification. 15 84

Echolalia, the parroting of the speech of others, is a severe communication disorder frequently associated with childhood schizophrenia and mental retardation. Two echolalic children, one schizophrenic and one retarded, were treated in a multiple-baseline design across subjects. Each child was taught to make an appropriate, non-echolalic verbal response (i.e., "I don't know") to a small set of previously echoed questions. After such training, this response generalized across a broad set of untrained questions that had formerly been echoed. The results obtained were the same irrespective of the specific experimenter who presented the questions. Further, each child discriminated appropriately between those questions that had previously been echoed and those that had not. Followup probes showed that treatment gains were maintained one month later. The procedure is economical, in that it produces a rapid and widespread cessation of echolalic responding.
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PMID:Elimination of echolalic responding to questions through the training of a generalized verbal response. 73 Jun 31

Fragile X syndrome is the second most common chromosomal cause of mental retardation (MR). The calculated incidence is 1/1000, making accurate and early diagnosis important for specific preventive, pharmacologic, and cognitive treatment. The timely diagnosis in males is facilitated by the characteristic phenotype and an association with autism. In contrast, in females heterozygous for fragile X, the characteristic phenotype and infantile autism are rarely reported. We present two females with cytogenetic expression of the fragile X chromosome for whom the studies were performed because of the presence of autism or prominent autistic features and a behavioral and physical phenotype consistent with fragile X syndrome. The first female, age three years, has autism, hyperactivity, echolalia, language delay, hand stereotypies, and mild MR. The characteristic phenotype was not present nor was there a family history of X-linked MR. Fragile X expression was 6% in the proband, 3% in the mother and 1% (normal) in the father. The second child, seven years old, has prominent autistic features, hyperactivity, mild MR, mild language disorder, and a family history consistent with X-linked MR. Fragile X expression was 3% in the proband and 0% in the mother. These cases support the occurrence of fragile X in autistic females and emphasize the importance of cytogenetic screening for fragile X in this high risk population. Early diagnosis of fragile X allows precise genetic counseling and more specific cognitive and pharmacologic treatment.
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PMID:Autism in association with fragile X syndrome in females: implications for diagnosis and treatment in children. 320 May 5

Fragile X syndrome is a recently identified form of mental retardation that is associated with a chromosomal abnormality and inherited in an X-linked manner. Previous studies have suggested that distinctive speech and language characteristics are associated with the syndrome. Twelve adult male residents of an institution for the retarded (aged 23 to 51 years) were compared on a series of speech and language measures to 12 adult males with nonspecific forms of MR who were residents of the same institution and were matched on age and IQ. A second contrast group consisted of similarly matched autistic men. Results revealed that there were no significant differences among the groups' performance, with the exception of increased rates of echolalia in the autistic group. A nonsignificant trend toward poorer performance on expressive measures on the part of the fragile X group was noted. The implications of these findings for further research on the syndrome are discussed.
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PMID:A comparison of language characteristics of mentally retarded adults with fragile X syndrome and those with nonspecific mental retardation and autism. 347 23

There are reports of sex chromosomal abnormalities including XXY, XYY, and fragile X karyotypes in autistic individuals, but structural autosomal defects have rarely been reported. This paper presents four patients with autism, mental retardation, minor dysmorphic features, and structural autosomal defects. These patients shared autistic features including fascination with inanimate objects, catastrophic reactions to changes in their environment or their daily routine, echolalia, and poor relatedness; IQ scores indicate mild to severe retardation. Their autosomal abnormalities included inversion/duplications of 3p and 16q, 5p+, and 17p-. Parental chromosomes were all normal. Chromosomal analysis should be performed on mentally retarded, autistic individuals, especially those with minor physical anomalies and no specific etiology for their retardation.
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PMID:Autism, mental retardation, and chromosomal abnormalities. 354 57

Inadequate language is a defining feature of the autism spectrum disorders (autism). Autism is a behaviorally and dimensionally defined developmental disorder of the immature brain that has a broad range of severity and many etiologies, with multiple genes involved. Early studies, which focused on the language of verbal children on the autistic spectrum, emphasized aberrant features of their speech such as unusual word choices, pronoun reversal, echolalia, incoherent discourse, unresponsiveness to questions, aberrant prosody, and lack of drive to communicate. Persistent lack of speech of some individuals was attributed to the severity of their autism and attendant mental retardation rather than possible inability to decode auditory language. Clinical study of unselected children with autism indicated that the language deficits of preschoolers fall into two broad types, perhaps with subtypes, those that involve reception and production of phonology (sounds of speech) and syntax (grammar), and those that do not but involve semantics (meaning) and pragmatics (communicative use of language, processing, and production of discourse). Except for the preschoolers' universally deficient pragmatics and comprehension of speech, many of their language deficits parallel those of non-autistic preschoolers with developmental language disorders. There is now biological support for the clinical observation that young autistic children are language disordered as well as autistic. Recent electrophysiological studies disclose auditory input abnormalities in lateral temporal cortex even in verbal individuals on the autistic spectrum. Severe receptive deficits for phonology enhance the risk for epilepsy. Genetic studies indicate that linkage to chromosome 7q31-33 is limited to families with evidence for phonologic impairment as well as autism. Clearly, social and cognitive disorders alone provide an inadequate explanation for the range of language deficits in autism.
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PMID:Update on the language disorders of individuals on the autistic spectrum. 1268 94

The fragile X syndrome (FRAX) is the most common familial form of mental retardation. The incidence is estimated at 1 in 4000 males. The leading symptom of the syndrome is mental retardation, with accompanying behavioural problems. About 25-35% of affected persons meet the criteria of autism. The behavioural problems involve attention problems, hyperactivity, tactile defensiveness, speech problems (echolalia), aggression, emotional problems, depression, anxiety, and stereotypic movements. There is no causal treatment and management is mainly symptomatic. Many specialists should be involved in this process. Behavioural and educational therapy is indicated. The basic step is identification of the child's problems. Its goal is to promote development of the child's abilities. Pharmacological intervention should be accompanied by supporting methods. The diagnosis of FRAX involves the entire family. The family members should be offered genetic counselling and the possibility of diagnostic DNA analysis.
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PMID:[Advances in treatment of fragile X syndrome]. 2108 95