We did a comprehensive MEDLINE search with the MeSH terms “learning disability” and “mental retardation” from 2000 until August 2002. Only articles published in English were retrieved. Additionally, we undertook a hand search of abstracts published in J Intellect Disabil Res, Ment Retard, Am J Ment Retard, Ment Retard, Ment Retard Dev Disabil Res, Autism, and J Autism Dev Disord during the same period. Only papers deemed to provide important insights or that had further reading value have been
SeminarLearning disability
Section snippets
Definitions and demographics
Learning disability and mental retardation are administrative labels applied to individuals who consistently test below a certain IQ level (usually 70) and who show functional impairment as a consequence of low IQ (panel).1, 2 While there is no generally accepted definition of intelligence, good evidence exists that the concept of so-called general intelligence has good validity.5 Additionally, there is mounting support for the notion that individual IQ differences are linked to differences in
Causes and pathogenesis
The link between a specific agent and a particular level of IQ is not known. Both genetic and environmental factors contribute to a wide variety of neurodevelopmental and neuropsychiatric disorders, including autism and learning disability.15 Some heritable disorders approach 100% penetrance, but even here the clinical presentation may be affected by environmental factors.16 Data showing a high rate of abnormal dermatoglyphics in people with learning disability suggested that environmental
Behavioural phenotypes
The so-called behavioural phenotype syndromes39 have recently come to the forefront as an important area of research and development of clinical services. Behavioural phenotypes are conditions with a known, usually genetic, cause, and a characteristic behavioural presentation. Down's, 22q11-deletion, fragile X, Prader-Willi, Angelman's, Rett's, and Smith-Magenis syndromes, and the fetal alcohol syndrome are some of the best known examples. Each of these syndromes is rare (occurring in one in
Forensic issues
The risk of conviction for violent offences is increased in people with learning disability.116 Low IQ, especially low verbal IQ, is common among violent offenders.117, 118, 119, 120, 121, 122 This association has not been accounted for by socioeconomic or educational status.123 The most common types of crime are sexual child-abuse (ranging from childlike mutual exploration to very dangerous crimes) and arson.124 Special needs are probably not met for the learning disability population in
Neuropsychology
Many studies are published every year about the neuropsychology of specific behavioural phenotype syndromes, but not enough is known about the neuropsychological profile of learning disability in general. People with learning disability are often assumed to have an overall equally depressed amount of intellectual function, which would show up as generally poor scores on all neuropsychological tests. The available evidence does not support such a notion. For instance, special location memory is
Psychosocial issues
200 years ago, children with learning disability were often abandonded to die. The eugenics movement during the earlier part of the 20th century reified prejudices about people with learning disability, including the stance that they should be sterilised to avoid spreading their genes to future generations. In the last 25 years or so, people with learning disability have come to be regarded with increased respect. Their right to sexual self-expression is now openly discussed.126 Furthermore, we
Mortality
Mortality is increased among individuals with learning disability.130 Cause-specific mortality also differs from that of the general population; deaths from cancer and external causes are less frequent. Non-mobile children and those incapable of feeding themselves may be at particular risk of short life expectancy.131 Both the scope and pattern of disease mortality and cause-specific mortality tend to become increasingly similar to those of the general population after age 40 years.
Outcome
The long-term outlook for individuals with low IQ has been neglected. The severity of childhood learning disability is probably the most powerful predictor of adult adaptive functioning,131 regardless of the underlying cause. However, prognosis will usually be more reliable if the underlying cause is known. Most adults with learning disability have very limited economic resources.132 The outcome of autism has been more frequently assessed than that of learning disability. The autism studies
Treatment and intervention
Diagnostic work-up should be undertaken by professionals well trained in learning disability. The table outlines a minimum level of work-up.
No single pharmacological, psychological, or educational treatment is available for learning disability. However, claims have been made that nootropic drugs may enhance cognitive performance,135 and findings of at least one study136 suggest a substantial increase in IQ after 15 months of treatment with amphetamine for attention-deficit hyperactivity
Society's attitudes
Negative attitudes to people with learning disability can be changed through so-called attitude training.152 Adolescent girls and people who have frequent contact with individuals with learning disability have more positive attitudes than men and those who rarely meet people with learning disability.153 A most important aspect of negative or ignorant attitudes towards people with learning disability is reflected in the tendency—clinically and in research—to produce acquiescence in interviews
Search strategy and selection criteria
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Adolescent psychosis and transdiagnostic delimitations to other clinical syndromes
2023, Adolescent Psychosis: Clinical and Scientific PerspectivesAuditory processing disorder evaluations and cognitive profiles of children with specific learning disorder
2019, Clinical Neurophysiology PracticeCitation Excerpt :At least one symptom among comprehending difficulties in reading, writing, and academic skills must be present for a definite diagnosis. SLD affects 1–2.5% of the occidental population and encompasses different conditions that lead to functional disorders; it requires monitoring and interventions throughout life, including regular medical follow-ups and health-care interventions (Gillberg and Soderstrom, 2003). There are different factors that may interfere with the identification of SLD, such as temporal processing alterations, auditory processing disorders (APD), eye movement alterations during reading, and attention deficit and hyperactivity disorder (ADHD), among other comorbidities, which contributes to the complexity of the assessment and to the necessity of designing effective interventions.
Neurodevelopmental disorders in young violent offenders: Overlap and background characteristics
2017, Psychiatry ResearchPhysical activity during school and after school among youth with and without intellectual disability
2016, Research in Developmental DisabilitiesCitation Excerpt :First, the low number of girl participants with ID reduced the statistical power of the study. This low number was due to the fact that fewer girls are diagnosed with ID than boys (Gillberg & Soderstrom, 2003), resulting in fewer potential participants, making it hard to overcome this limitation. Second, as mentioned, the cut-off used for MVPA was established and validated on TDI children and adolescents, which may exaggerate the differences between the groups, but to the best of our knowledge, no cut-offs have been established or validated for individuals with ID.
Infant Motor Delay and Early Symptomatic Syndromes Eliciting Neurodevelopmental Clinical Examinations in Japan
2016, Pediatric NeurologyCitation Excerpt :More recently, there has been a report showing motor delays at age 6 months to be associated with autism spectrum disorder (ASD) at age 36 months.4 For a quarter of a century, it has been well established that several of the groups of disorders included under the umbrella term of Early Symptomatic Syndromes Eliciting Neurodevelopmental Clinical Examinations (ESSENCE)5—including attention-deficit/hyperactivity disorder (ADHD), ASD, speech and language disorder (SLD), intellectual developmental disorder (IDD), and epilepsy—are associated with abnormalities of early motor development, such as early-onset motor control problems, ranging from general clumsiness and reduced fine motor skills to coordination difficulties and visuomotor or visuoperceptual function disruption.6-12 The motor control problems are nowadays increasingly diagnosed separately as developmental coordination disorder (DCD), which, in itself, is a category also subsumed under the ESSENCE concept.
Diabetes in people with intellectual disabilities: A systematic review of the literature
2015, Research in Developmental DisabilitiesCitation Excerpt :ID remains the most widespread, universally recognised term and will be utilised throughout this paper. People with ID constitute 1–2.5% of the population in the Western world (Gillberg & Soderstrom, 2003). Studies from England (Emerson et al., 2012) and Australia (Wen, 2004) report similar prevalence rates of 2% and 2–3% respectively.