Attention Deficit Hyperactivity Disorder:
Overview with Implications for Residential Treatment and
Therapeutic Schools

Jay J. Jones
Fresno, California

Etiology

Many causal explanations have been given for the cluster of symptoms we now call ADHD. The DSM-III-R reports that children are predisposed to developing ADHD if they have central nervous system abnormalities, come from chaotic environments, or were exposed to child abuse. Although the DSM-III-R claims to give minimal consideration to causes, these statements about predisposition do imply etiological origins.

Neurological

Neurological causes for ADHD have been among the earliest speculations about the etiology of the disorder. Yet Quay and Werry (1986) believe there are few hard data to support the speculation that ADHD comes from neurological causes. It has been a popular belief that ADHD children have some undetectable brain damage, more recently described as brain dysfunction (Barkley, 1981; Ross & Ross, 1976). It is also speculated that maturational delays are causal factors in the disorder (Ross & Ross, 1976). Some theorize that a condition of "under arousal" of the central nervous system is responsible for most of the ADHD symptoms. Competing theories of both under arousal and over arousal have been presented (Quay & Werry, 1986).

Environmental

Environmental factors are believed to play an important role in the development of the ADHD disorder. Various researchers have hypothesized that lead exposure, food allergies, or allergies to food additives and dyes (Barkley, 1981; Garfinkel & Wender, 1989; Quay & Werry, 1986; Ross & Ross, 1976) may cause the disorder. Yet recent research has suggested that such environmental "toxins" account for only a small percentage of the ADHD etiological explanation (Barkley, 1981; Quay & Werry, 1986). This seems particularly evident considering that diminishing the degree of exposure to environmental toxins only has a significant therapeutic effect on a small number of the ADHD children (Barkley, 1981; Garfinkel & Wender, 1989).

Other environmental factors, such as family environment, have also been thought to play a role in the development of ADHD. In particular it has been noted that children are vulnerable to ADHD who come from chaotic home environments (Barkley, 1981). Children are also vulnerable who come from homes where there has been family loss, family breakdown, or disruption in early bonding (Ross & Ross, 1976). Attention has also been focused on the high incidence of ADHD inchildren of tobacco smoking mothers (Ross & Ross, 1976). It has been a common finding that ADHD children come from families where mothers have consumed or abused alcohol during pregnancy (Barkley, 1981; Ross & Ross, 1976). There seems to be a very high rate of alcohol abusive family members in the ADHD population (Hamden-Allen, Stewart & Beeghly, 1989; Lambert, 1988; Manshadi & Lippman, 1983). This, in turn, relates to a high rate of alcohol abuse in the older ADHD (Gittelman & Manuzza; Lambert, 1988).

Unfortunately, correlations such as maternal tobacco use, parental and familial alcohol abuse, and drug abuse--although associated with ADHD families--prove difficult for researchers to show a cause and effect relationship to ADHD. This impedes understanding whether these are truly environmental issues or genetic issues.

Genetic

Genetic factors are thought to have a role in the development of the ADHD syndrome. Early biological characteristics have been observed in children who later develop ADHD. This supports the genetic cause hypothesis (Lambert, 1988). It has been observed by various clinicians and researchers that ADHD is found in higher rates in some families than in others (Garfinkel & Wender, 1989; Ross & Ross, 1976). Strong evidence of the genetic link has been found in studies of twins, and in adoption studies. These studies seem to present evidence that limits the speculation that the higher incidence of ADHD in first degree relatives is because of environmental or psychosocial considerations alone (Garfinkel & Wender, 1989; Manshadi & Lippman, 1983; Quay & Werry, 1986; Ross & Ross, 1976).

Genetic issues include the presence of a higher rate of psychiatric problems in the families of ADHD children than in the general population. There is a higher incidence of other family members with ADHD symptoms in particular families (Barkley, 1981; Ross & Ross, 1976). There is an unusually high rate of alcohol abuse and alcoholism in the family members of ADHD children (Manshadi & Lippman, 1983). There are frequent findings that these families have a higher incidence of hysteria, depression, and psychopathy (Barkley, 1981).

Again, some researchers postulate that ADHD symptoms are caused by exposure to family members with pathological conditions. Yet adoption and twin studies strengthen the argument that genetically related causal factors contribute to the development of ADHD, despite whether the child has ever been exposed to the parent directly.

Last Modified: Tuesday, November 11, 1997 9:07:44 PM