Autism

A neurodevelopmental condition nowadays conceptualized as a spectrum, involving difficulties in social development, verbal and non-verbal communication, absence of imaginative play, and a focus on unusually strong and narrow interests.  In classic autism, about half of all afflicted individuals are mute or speak intelligibly only once or twice in their lifetimes, and about 80 percent of persons with autism are classified as being mentally retarded.  What distinguishes them from others with mental retardation is their detachment from the world around them and a lack of understanding of others’ feelings and emotions, together with a greater likelihood of a cluster of strange behaviors (e.g., odd postures, rocking, hand-flapping, unusual food preferences, avoidance of eye contact, insensitivity to pain, head-banging, and other forms of self-injurious behaviour).  Apart from Asperger’s syndrome, other disorders sharing some of the behavioral features of autism are the fragile X syndrome and Rett’s syndrome.  The birth prevalence of autism is 4.5 for every 10,000 live births, but when all pervasive developmental disorders are considered (including Asperger’s syndrome) the figure becomes 15-20 per 10,000 live births.  As with developmental dyslexia, there are data reporting that that three or four times as many boys as girls have autism, but that figure is disputed by some who argue that too few girls are diagnosed with the disorder due to different expectations about what constitutes sex-typical patterns of behavior.  Recent research into the biological markers and possible determinants of autism has resulted in a plethora of findings.  Inevitably, chromosome 15 and the region known as chromosome 15q11-q13 deletion has been implicated, as it has in Angelman and Prader-Willi syndromes.  Another region on chromosome 15 that includes three GABA receptor sub-unit genes (GABRB3, GABRA5, GABRG3 that together form GABA receptors) may also contribute to the development of autism, with the GABRB3 and GABRG3 genes, but not GABRA5, being the leading candidates.  Other considerations involve, for example, some sort of autoimmune disorder, high levels of testosterone in the amniotic fluid during pregnancy, Vitamin A deficiency, white matter disorders in the brain, and abnormalities in the cerebellum as revealed by brain imaging (e.g., deficiency of cells in the vermis, reductions in the size and number of Purkinje cells).  The latter findings suggest that autistic children may have problems in motor development and motor learning.  Despite claims to the contrary, there is no proven treatment for autism.  Some form of behavior modification therapy has been tried, but findings are inconclusive, as is the case for the administration of large doses of vitamin B together with magnesium.  What is worrying is a seemingly widespread tendency to prescribe pharmaceutical agents as a means of treating autism in both children and adults, which include antidepressants, lithium, and Ritalin.  Perhaps the first person to describe behavior resembling that of an autistic child was the physician Jean Marc Gaspard Itard (1774-1838) in 1801, with his account of the ‘wild boy of Aveyron’, a feral child who lived in a forest and who Itard called Victor.  It appears that the psychiatrist Eugene Bleuler (1857-1940) came up with the term ‘autism’, meaning ‘aloneness’, to refer to the mental state of ‘schizophrenia’, previously known as dementia praecox.  It was borrowed by the child psychiatrist Leo Kanner (1894-1981) who is generally acknowledged as providing the first clinical description of the disorder in 1943.  He referred to it as early infantile autism and it became known as Kanner’s syndrome. Those children fitting Kanner’s description appear to constitute about 10% of all individuals classified as having autism, and display behavioral phenotypes noted to a lesser degree in other autistic children (e.g., exceptional memory, fascination with mechanical objects, insistence on uniformity in the environment such as having the furniture always placed in a specific order, and unusual skills in music, art, or computation).  Finally, regressive autism in which children appear to attaining developmental milestones at appropriate ages, but then suddenly stop progressing and begin to regress into the classical pattern of autistic behavior, has since 1998 attracted increasing attention due to a British study reporting an association with the MMR vaccine in a sample of 12 children.  As yet, there seems to be no end to the controversy engendered by this study, although large-scale studies, especially one in Japan, are beginning to refute the association.

See Amygdala, Angelman syndrome, Asperger’s syndrome, Auditory rote memory, Autism Diagnostic Observation Schedule (ADOS), Behavior modification, Birth prevalence, Configural perception, Central coherence, Chromosome, Configural processing, Developmental delay, Developmental disorders, Display rules, Echolalia, Embedded Figures Test (EFT), Empathizing/empathy, Endorphins, Fragile X syndrome, Human Connectome Project (HCP), Joint attention, Medial (pre-) frontal cortex, Mind-blindness theory, Mind reading, Mirror neurons, Motor inhibition, Obsessive compulsive disorder (OCD), Oligogenic mode of inheritance, Orbitofrontal frontal cortex, Other mind problem, Oxytocin, Prader-Willi syndrome, Purkinje cells, Rett’s syndrome, Selective (or elective) mutism, Surrogate endpoint, Sympathy, Systemizing, Testosterone, Theory of the child’s mind (ToM), Tower test