First described and named by Leo Kanner in 1944, the mysterious disability of autism is characterized by a peculiar emotional and intellectual detachment from other people and the common human world.
In autistic children, an impaired capacity for communication and human relationships and a severely restricted range of activities and interests become evident before the age of three. Although the symptoms vary in nature and severity, language and the capacity for a normal social life are always seriously affected. Two to four out of 10,000 children are autistic; 75% of them are boys (Chase et al. , 1993). The earliest signs may appear in the first months of life.
Autistic infants often shrink from touch. Instead of cuddling when picked up, they may go limp or stiffen, and they do not cling to parents who return after an absence (de Benedetti, 1993). Normally, infants will smile at the sound of their mothers voice when they are two or three months of age. Later, in the first year, they begin to reach with their hands, carry on wordless conversations and eventually progress to syllables like ma and pa. Before the end of the first year they are pointing out objects to others attention and looking sad when someone else looks sad or anxious.
Many autistic children never reach these stages or pass through them at a later age (Loesche, 1990). In infancy, the symptoms may be subtle and almost unnoticeable or optimistically disregarded by parents, but it is usually clear by age two or three that something is wrong (Baranek, 1999). Autistic infants have little interest in others or understanding of their needs and feelings. They do not maintain eye contact and seem barely able to distinguish their parents from strangers.
They ignore other children and prefer repetitious, solitary play, such as staring at revolving objects. Their air of detachment and drive for solitude sometimes create the impression that they come from or live in a world not ours, and it has been suggested that autism is the source of stories about children who are fairy changelings (Harrison, 1996). There are many questions as to what exactly causes autism. Prospective studies of young children (18-24 months) have highlighted the importance of social-communicative functions as early predictors of a later, more reliable diagnosis of autism (Baron-Cohen et al.
, 1996, as cited in Tustin, 1993), The absence of typically developing, pre-linguistic functions such as showing objects, joint affection, affective exchanges, pretend play and imitation have been successfully cited as markers of autism in young children and these are thought to be precursors of later appearing deficits in social relatedness and communication. However, the predictive validity of these behaviors appears questionable prior to about eighteen months of age. Perhaps some of these indicators may need to be considered (Tustin, 1993). Loeshe (1990) suggested that abnormal perceptual responses as well as social deficits may be likely indicators of autism during infancy. Although social cognition and communicative functions have been investigated widely, there is a lack of empirical information about the various qualitative aspects of sensory-motor behaviors that may be disrupted early in the development of children with autism. These types of difficulties are reported extensively in older children with autism as well as in retrospective accounts of the infancy period based on medical chart reviews and/or parental reports.
An empirical study of sensory-motor functions early in the development of autism could reveal potential markers of autism that, while subtle, may prove foundations to later evolving symptoms either within or outside of the sensory-motor domain. Sensory-motor processes are salient from birth and thus may be easily observable throughout infancy-prior to the development of abnormalities in many of the higher level representational capacities that currently have evoked much interest in research (Loesche, 1990). Another possible cause is genetics. Autism almost certainly has a strong genetic basis. Among brothers and sisters of autistic persons, the rate of both autism itself and milder related symptoms is 50 to 100 times higher than average.
The matching rate for autism in identical twins in 65-90%; for fraternal twins, it is close to the sibling average. A statewide survey undertaken in Utah in the 1980s found that among eleven families with an autistic father, .
