Autism Health Article

Definition

The term "autism" refers to a cluster of conditions appearing early in childhood. All involve severe impairments in social interaction, communication, imaginative abilities, and rigid, repetitive behaviors. To be considered an autistic disorder, some of these impairments must be manifest before the age of three.

The reference book used by mental health professionals to diagnose mental disorders is the Diagnostic and Statistical Manual of Mental Disorders, also known as the DSM. The 2000 edition of this reference book (the Fourth Edition Text Revision known as DSM-IV-TR) places autism in a category called pervasive developmental disorders. All of these disorders are characterized by ongoing problems with mutual social interaction and communication, or the presence of strange, repetitive behaviors, interests, and activities. People diagnosed with these disorders are affected in many ways for their entire lives.

Description

Each child diagnosed with an autistic disorder differs from every other, and so general descriptions of autistic behavior and characteristics do not apply equally to every child. Still, the common impairments in social interaction, communication and imagination, and rigid, repetitive behaviors make it possible to recognize children with these disorders, as they differ markedly from healthy children in many ways.

Many parents of autistic children sense that something is not quite right even when their children are infants. The infants may have feeding problems, dislike being changed or bathed, or fuss over any change in routine. They may hold their bodies rigid, making it difficult for parents to cuddle them. Or, they may fail to anticipate being lifted, lying passively while the parent reaches for them, rather than holding their arms up in return. Most parents of autistic children become aware of the strangeness of these and other behaviors only gradually.

Impairments in social interaction are usually among the earliest symptoms to develop. The most common social impairment is a kind of indifference to other people, or aloofness, even towards parents and close care-givers. The baby may fail to respond to his or her name being called and may show very little facial expression unless extremely angry, upset, or happy. Babies with autism may resist being touched, and appear to be lost in their own world, far from human interaction. Between seven and 10 months of age, most infants often resist being separated from a parent or well-known caregiver, but these infants may show no disturbance when picked up by a stranger.

Other children with autism may be very passive, although less resistant to efforts by others to interact. However, they do not initiate social interaction themselves. Still others may attempt to engage with adults and peers, but in ways that strike others as inappropriate, or odd.

In adolescence and adulthood, some of the higher-functioning individuals with autistic disorders may appear overly formal and polite. They may react with little spontaneity, as if social interaction doesn't come naturally or easily to them, and so they are trying to follow a pre-determined set of rules.

Some individuals with autism have normal intelligence, and many have special talents in areas such as music or memory. However, individuals with autism may have other mental or emotional problems that co-exist with their autism. Some of these other disorders may include impulse control disorders, obsessive-compulsive disorder, mood and anxiety disorders, and mental retardation.

Causes

PSYCHOLOGICAL AND FAMILY FACTORS.Although Henry Maudsley, in the late 1800s, was the first psychiatristto focus on very young children with mental disorders, it was the psychiatrist Leo Kanner who coined the phrase "early infantile autism" in 1943. Kanner believed that the parents of children with autistic behaviors were emotionally cold and intellectually distant. He coined the term "refrigerator parents" to describe them. His belief that parental personality and behavior played a powerful role in the development of autistic behaviors left a devastating legacy of guilt and self-blame among parents of autistic children that continues to this day. Recent studies are unequivocal, however, in demonstrating that parents of autistic children are no different from parents of healthy children in their personalities or parenting behaviors. In fact, many families with an autistic child also have one or more perfectly healthy children.

Because autistic children can be extremely sensitive to change, any change within the family situation can be potentially traumatic to the autistic child. A move, divorce, birth of a sibling or other stressors that occur in the lives of most families may evoke a more extreme reaction from an autistic child.

NEUROLOGICAL AND BIOLOGICAL FACTORS.While there is no single neurological abnormality found in children with autistic disorders, some research using non-invasive brain imaging techniques such as magnetic resonance imaging(MRI) suggests that certain areas of the brain may be involved. Several of the brain areas being researched are known to control emotion and the expression of emotion. These areas include the temporal lobe (large lobe of each side of the brain that contains a sensory area associated with hearing), the limbic system, the cerebellum, the frontal lobe, the amygdala, and the brain stem, which regulates homeostasis (body temperature and heart rate). Recent research has focused particularly on the temporal lobe because of the finding that previously healthy people who sustain temporal lobe damage may develop autistic-like symptoms. In animal research, when the temporal lobe is damaged, social behavior declines, and restless, repetitive motor behaviors are common. When measured by MRI, total brain volume appears to be greater for those with autistic disorders.

Other neurological factors include lesions to the brain, congenital rubella, undiagnosed and untreated phenylketonuria (PKU), tuberous sclerosis, and Rett's disorder(a related condition in which the baby develops in an apparently normal manner through age five months, and then begins to lose communicative and social interaction skills). There is also evidence of a higher proportion of perinatal complications (complications arising around the time of giving birth) among children with autistic symptoms. These complications include maternal bleeding after the first trimester and meconium in the amniotic fluid. (Meconium is a substance that accumulates in the bowel of the developing fetus and is discharged shortly after birth.) Some evidence suggests that the use of medications during pregnancy may be related to the development of autistic symptoms. As newborns, children with autistic behaviors show a higher rate of respiratory illness and anemia than healthy children.

ALLERGIES, INFECTIONS, AND IMMUNIZATIONS.Some professionals believe that autistic disorders may be caused by allergies to particular fungi, viral infections, and various foods. No controlled studies have supported these beliefs, but some parents and professionals report improvement when allergens and/or certain foods are eliminated from the diet.

Viral infections of the mother, such as rubella, or of the young child, such as encephalitis, mumps, and measles, occasionally appear to cause autistic disorders. The common childhood immunization series known as MMR (measles, mumps, rubella) has recently come under scrutiny as a possible cause of some autistic conditions.