Autism Spectrum Disorder


Mabel Lopez, Ph.D.

Autism is a pervasive developmental disorder characterized by three core features: (1) social impairment, (2) communication deficits, and (3) restricted activities and interests (American Psychiatric Association, 1994). Autism affects all races and social classes. Onset is during infancy or childhood and is usually associated with global cognitive deficits. Autism is a relatively rare disorder, with a prevalence of approximately 4-13 children per 10,000 (Stone, MacLean, and Hogan, 1995). Autism appears to be more common in boys than girls by a ratio of 3 to 4:1, but girls may be under diagnosed because of fewer behavior problems and better language and social skills (Edwards and Bristol, 1991).

Diagnosis of autism is complicated by a lack of biological marker and a wide range of behavioral manifestations seen among individuals afflicted with the disorder (Stone et al, 1995). Consequently, treatment must often be tailored to the individual needs of the autistic individual. This paper will provide a brief and general overview of diagnostic and treatment issues in the field of autism. In addition, some of the problems inherent in the diagnosis and treatment of autism will be discussed.


Correct diagnosis depends on an accurate developmental history focused on types of behavior typical of autism and on the evaluation of current functional skills. Cognitive and behavioral evaluation should include an assessment of the following areas:

(1)  sociability — an interest in persons rather than objects and the ability to engage joyfully in an activity initiated by someone else and, in young children, in imaginative play with representational toys.

(2)  language–comprehension, production and conversational use of speech, and voice quality).

(3)  the patient’s choice of activities–including the presence of stereotypic and pointless activities.

The use of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) (see Appendix A for a list of autism disorder criteria) and any of the other several autism-specific diagnostic inventories (e.g., Autism Diagnostic Interview and the Parent Interview for Autism) substantially increases diagnostic reliability (Stone et al, 1995).

Differential Diagnosis. There are no clear biological indications or medical tests that can unequivocally detect autism. In fact, there is great variability among individuals afflicted by autism. Moreover, there seems to be a great deal of overlap between other disabilities and autism (Stone et al, 1995). Consequently, the differential diagnosis of autism is often complicated. For instance, Asperger’s syndrome, pervasive developmental disorder not otherwise specified, Heller’s syndrome, and Rett’s disorder are pervasive developmental disorders that should be considered before a diagnosis of autism is reached.

Asperger’s syndrome is the disorder in non-retarded, often clumsy children without speech delay who have deficit sociability and a narrow range of interests. “Pervasive developmental disorder not otherwise specified” is the disorder in the children with autistic behavior who do not fulfill the criteria for any of the other disorders on the spectrum. Disintegrative disorder (Heller’s syndrome) is the disorder in previously completely normal children who undergo a massive regression between the ages of 2 and 10 years, resulting in severe acquired autism, usually with loss of cognitive skills. By definition, it does not occur in the context of a degenerative disease of the brain or schizophrenia. Rett’s disorder is a specific disorder limited to girls with acquired microcephaly, infantile regression, lack of hand use, striking stereotypic hand movements, severe retardation, and other neurological problems (American Psychiatric Association, 1994).


The approach that works best for the child with autism is the one that is the most specific to a given child’s needs. Specificity in planning an individualized education program is most likely to determine the success or failure of an intervention and education program. Specificity is achieved by considering the developmental strengths, needs, and excesses for each child. Children with autism demonstrate highly individualized learning styles both across and within students (Schreibman, Koegel, Charlop, & Egel, 1990). The learning style of each child with autism is unique. One child may require a higher level of intrusive instruction, whereas another may be overstimulated by that same level of stimulation. For example, the reaction, tolerance, or sensitivity of the teacher’s voice volume or the duration and intensity of touching may vary considerably among children with autism. Other factors, such as stimulus over-selectivity, the child’s motivation for a particular form of stimulation, capacity for sequential learning, and propensity for self-stimulation, contribute to the success or failure of the child’s program whether in the classroom or at home. Functional patterns of communication, self-injurious behavior, and social awareness need to be assessed for each child to achieve an optimal educational outcome. All of these differences must be considered while selecting an approach to educating the child with autism (Dunlap, Koegel, & Burke, 1981).

The child with autism benefits most from learning opportunities that occur across all environments. The ultimate learning environment is one that integrates learning opportunities in the child’s home, community, and school. An intervention and educational program that occurs primarily in one environment is necessarily limited. Moreover, children with autism benefit most when intervention is planned, systematic, individualized, and implemented at home, school, and the community. Intervention programming across environments is possible through a network of support services. A network of support services is formed and maintained by the efforts of service providers from regional centers, parent organizations, nonprofit helping organizations, advocacy groups, informed professionals in the community, and the school district. Services designed to support the effective learning environment, especially generalization of mastered skills, should be implemented at home, at school, and in the community. Such support services include behavioral parent training, respite care, medical intervention for treatment of hyperactivity and sleep disorder, counseling, and behavior management for aggression or self-injurious behavior (Berkell, 1992).

School districts provide specific special education services related to the student’s individualized education program when the instruction and services are necessary for the pupil to benefit educationally from his or her instructional program. These may include psychological services, occupational therapy, physical therapy, speech and language therapy, and others which may be provided directly by the school district or through contractual agreements with community agencies (Berkell, 1992).

The following is a brief summary of several different approaches to intervention programming. Discussion about these different approaches serves only as a brief overview of some of the recommended best practices. The particular combination of approaches selected will ultimately be determined by a number of factors specific to the child, family, school district, and community. Most often, these factors include the availability of qualified specialists, the philosophy and values of the family, the internal strength and resilience of the family, and the child’s developmental strengths and needs. No single approach is optimally effective. Furthermore, each approach involves aspects of the others.

Developmental Approach. Developmental concepts can be applied to the diagnosis and treatment of children with autistic spectrum disorders. For example, Bryna Siegel, an advocate of the developmental approach (Siegel, 1991), relates what is known about the symptoms of Autistic Disorder to what is known about the developmental level at which each of the child’s symptoms can appear. Siegel discusses the use of a developmental level as a way of organizing observations and accurately diagnosing autism. When there are differences between mental- and chronological-age levels, consideration must be given to whether or not the behavior is atypical (i.e., deviant or typical for that developmental level).

Proponents of a developmental approach to treatment (Greenspan, 1992) emphasize the child’s “ability to relate to others with warmth, pleasure, empathy, and growing emotional flexibility” as legitimate goals. The challenge in a strictly developmental approach is to help the child with autism to learn to “attend, relate, interact, experience a range of feelings, and, ultimately, think and relate in an organized and logical manner.” Design of the treatment program takes the child’s ability to process sensations into account. Treatment is relationship-based, is focused on opportunities for spontaneous relating, and relies on affect cueing to achieve results.

Applied Behavior Analysis. The behavior-analytic approach holds that “autism is a syndrome of behavioral deficits and excesses that have a neurological basis, but are nonetheless amenable to change in response to specific, carefully programmed constructive interactions with the environment” (Green, 1996). The emphasis on well-sequenced, structured teaching and on evaluation methods characteristic of applied behavior analysis make it uniquely well suited to the goal of effective instruction. A large body of research has shown that children with autism do not learn naturally from typical environments, but most can learn a great deal given appropriate instruction (Harris & Handleman, 1994; Koegel & Koegel, 1995).

Intervention programming that uses a behavior-analytic approach attempts to systematically teach small, observable steps that define a skill. Skills for which the child demonstrates readiness to learn are broken down into small steps. Each step is taught by presenting an external stimulus or instruction. If the child responds correctly, his or her response is followed by a predetermined positive consequence. If a reinforcement assessment has been conducted and a potent reinforcer is discovered for a given child, then that reinforcer functions effectively to strengthen the response. Research has shown that intervention and educational programming based on the principles and practices of applied behavior analysis can produce rapid, complex, and durable improvements in cognitive, social-communication, play, and self-help skills. Application of behavior-analytic principles are very effective in replacing and/or reducing maladaptive behavior (Siegel, 1996).

Biological and Medical Approaches. Children with autism vary greatly in their degree of need for medical intervention. They may be healthy, energetic, and have a normal sleep pattern or they may have one or more medical problems. The DSM-IV (American Psychiatry Association, 1994) recognizes that neurological abnormalities are reported in a significant percentage of children with autism.  The existence of a large literature describing a wide variety of neural abnormalities in autism has led to much speculation about the disease (Cohen and Volmar, 1997). However, a coherent anatomical or pathophysiologic theory of autism nor a biologic diagnostic test has yet been developed.

Neuropathological studies of a fewer then 35 brains of patients with autism are available; none were done with state-of-the-art methods (Bauman and Kemper, 1994) Preliminary findings from these studies include a paucity of Purkinje cells and granular cells in parts of the cerebellar cortex and smaller than normal, more tightly packed cells in some cerebellar nuclei and limbic structures, including the amygdala and hippocampus, suggesting prenatal dysgenesis. On average, the studied brains tend to be large.

EEGs are helpful when they reveal epileptiform activity. Brain-stem auditory evoked potentials are normal in the absence of hearing loss or diffuse brain damage (Klin, 1993).  Evidence of delays in the early negative components of auditory event-related potentials and abnormalities in late components associated with word classification supports the idea that there is aberrant processing of auditory language skills in autism (Klin, Kurtzberg, Brattson, 1995).

Guided in part by empirical neuropharmacologic studies, neurochemical research on autism has focused on neurotransmitters and neuromodulators (Cohen and Volmar, 1997): first the mesolimbic dopamine system; then, endogenous opioid systems and oxytocin; and, in current research, serotonin, examined because of an identified link between autism and affective disorders (DeLong, 1994) and the discovery of some favorable behavioral effects of serotonergic drugs (Chamberlain, and Herman, 1990).

In summary, there are a large variety of reported neurological abnormalities in autism but no unifying theory or explanation. Because of the latter medical problems medical interventions are being sought out as adjunctive treatments for children with autism (Anderson & Hershino, 1987). However, no drug or other treatment cures autism, and many patients do not require medication. However, psychotropic drugs that target specific symptoms may help substantially (see Table 1 for a summary of some medications used to treat autism).


Table 1: Medications Used in Patients with Autism. Data are from Cohen and Volkmar.

Type of Drug Examples Indications Principal Undesirable Effects
Stimulants Methylphenidate,
Attention deficit – hyperavtivity Irritability, aggressiveness,
stereotypies, tics,
sleeplessness; in rare cases,
hepatotoxicity of pemoline
Noradrenergic agents
(beta-blockers and
Propranolol, clonidine
(e.g., patch)
Explosive behavior, aggressiveness Depression, nightmares,
sleepiness, hypotension,
dry mouth
inhibitors and agonists,
Fluoxetine, clomipramine,
sertraline, fluvoxamine
Perseveration, obsessions, rigidity
aggressiveness, depression
Dry mouth, sleep disturbances,
constipation, agitation,
Haloperidol, thoridazine,
chlorpromazine, pimozide
Aggressiveness, destructiveness,
Sedation, affective blunting, dystonia,
parkinsonism, tardive and withdrawal
Anxiolytics Buspirone Anxiety Sedation, restlessness (rarely),
gastrointestinal symptoms

Sensorimotor Therapies Sensory approaches include auditory integration training (AIT) (Rimland & Edelson, 1995) and sensorimotor integration training (Ayers, 1979). Cook (1990) reviewed sensory integration theory and explained how it can be used to help children with autism. Cook discussed how children with autism process sensory information, how it affects their behavior, and how activities that incorporate their sensory needs assist in moving the children toward more self-directed behaviors. There are two basic approaches to the use of activities with children with autism: the task model or skills-sequence approach and the component model or the modality- processing model. Suggestions are given by Cook on setting up activity programs and documenting change.

Ray, King, and Grandin (1988) tested a nine-year-old boy with autism for 17 days over a four-week period by allowing five minutes of stimulation using a swing and sensory integration therapy. Data showed the percentage of vocalizations was significantly greater during the time the child used the swing and that the child acquired 13 new words during the study period.

Play. Play can be an intervention method to promote skills or an evaluation tool to aid in developmental assessment or diagnosis (Wulff, 1985). Children with autism often choose play activities that are self-stimulating, repetitive, or both. Play has a role in facilitating language and cognition. Play groups should be designed to facilitate positive social interactions, either verbal or nonverbal. Play group design allows the clinician to structure activities to accommodate the child’s level of functioning and create unique opportunities for new skills.

Wolfberg and Schuler (1993) describe a multifaceted model to promote peer play. They evaluate the impact of the model on the social and cognitive dimensions of play in three males with autism (ages seven years). Their model demonstrated decreases in isolated play, collateral gains in more social forms of play, decreases in stereotyped object play and collateral gains in functional object play. While no symbolic play was observed in any of the children during a baseline period prior to intervention, two children demonstrated symbolic play in the final condition. Measures of generalization and social validation indicated advances in play behavior that were not limited to the play groups but were observed in other contexts and were accompanied by language gains.

The appropriateness of play therapy has been questioned. Nevertheless, there are a number of case studies of play therapy used to treat autism. Lowery (1985) reported two cases of children with autism treated in weekly play therapy for one year. The children, a male and a female, were both six years old when they began treatment. Both appeared to function in the moderate range of mental retardation. Attachment behavior was an issue in both cases. Lowery’s approach demonstrated that these children’s capacity to form relationships developed in play therapy.


Autism is a developmental disorder that is usually diagnosed in early childhood. Although associated with organic factors, it is typically characterized and diagnosed by behavioral disturbances. Due to shared/similar features with other pervasive developmental disorders, autism is often difficult to diagnose. Moreover, due to the variety of symptoms encountered by individuals afflicted with autism, treatment is not universal and must be tailored to each individual’s need.

The most important intervention in autism is early and intensive remedial education that addresses both behavioral and communication disorders. The effective approaches use a highly structured environment with intensive individual instruction and a high teacher-to-student ratio. Occupational and physical therapy should address specific deficits. Moreover, parents need specific instruction in how to deal with the tantrums and destructive behavior and in useful techniques for keeping their children organized and occupied so as to minimize detrimental effects on the family.

Although, most of the research is geared at improving the quality of life and symptoms of the autistic individual, parents require ongoing counseling and support as well. First, they must understand that they are not responsible for their child’s condition. Desperate parents may need explicit counseling about the questionable value of unconventional, and often expensive, dietary, medical, and other therapies that, despite being without proved efficacy, are widely used. Parents must be given information about appropriate schools, respite facilities, parent groups, and other community-based support systems.

Adolescents and adults with autism often require assistance in securing meaningful work and living arrangements in group homes when their families are no longer able to provide shelter. Patients capable of living independently may need help in finding an appropriate and supportive school and job. One hopes that in the future only a minority of adults with autism will live out empty lives in institutions.

In essence, autism is a life-long disorder that has proven to be a true challenge in the field of pediatric psychology. Due to the complications inherent in diagnosis and treatment, individuals with autism do not always get the quality of service that they need. One way to circumvent this problem is to raise the awareness of health care providers and educators. More research in the areas of behavioral and pharmalogical interventions are necessary. In addition, the etiology of autism still needs to be established. The issues affecting the family members of autistic individuals must also be explored and addressed.





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Anderson, G.M., & Hirshino, Y. (1987). Neurochemical studies of autism. In D.J. Cohen, & A. Donnellan (Eds.), Handbook of autism and pervasive developmental disorders (pp. 166- 191). New York: Wiley.

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Appendix A

Critera for Autism Disorder:

 DSM-IV Criteria

A total of six or more manifestations from 1, 2, and 3 below:


1. Qualitative impairment of social interaction (at least two manifestations)
a. Marked impairment in the use of multiple types of nonverbal behavior such as
eye to eye gaze, facial expression, body postures, and gestures to regulate social interactions;
b. Failure to develop peer relationships appropriate to developmental level;
c. Lack of spontaneous seeking to share enjoyment, interests, or achievements
with other people (e.g., by lack of showing, bringing, or pointing out objects of interest); and
d. Lack of social or emotional reciprocity.


2. Qualitative impairment of communication (at least one manifestation)
a. Delay in, or lack of, development of spoken language (not accompanied by an attempt to
compensate through alternative modes of communication such as gestures or mime);
b. In individuals with adequate speech, marked impairment in the ability to
initiate or sustain a conversation with others;
c. Stereotyped and repetitive use of language or idiosyncratic language; and
d. Lack of varied, spontaneous make-believe play or social imitative play appropriate
to developmental level.


3. Restrictive and stereotyped patterns of behavior, interests, and activities (at least one behavioral manifestation)
a. Encompassing preoccupation with one or more restricted, repetitive, and stereotyped
patterns of interest that is abnormal either in intensity or focus;
b. Apparently inflexible adherence to specific, nonfunctional routines or rituals;
c. Stereotyped and repetitive motor mannerisms (e.g., hand or finger flapping or twisting,
or complex whole-body movements); and
d. Persistent preoccupation with parts of objects.


Delays or abnormal functioning, with onset before the age of 3 years, in at least one of the following areas:
Social interaction;
Language as used in social communication; and
Symbolic or imaginative play.

A determination that Rett’s disorder or childhood disintegrative disorder does not account better for the observed symptoms

 DSM-5 Criteria:

Autism Spectrum Disorder           299.00 (F84.0)

Diagnostic Criteria

A.      Persistent deficits in social communication and social interaction across multiple contexts, as manifested by the following, currently or by history (examples are illustrative, not exhaustive, see text):

1.       Deficits in social-emotional reciprocity, ranging, for example, from abnormal social approach and failure of normal back-and-forth conversation; to reduced sharing of interests, emotions, or affect; to failure to initiate or respond to social interactions.

2.       Deficits in nonverbal communicative behaviors used for social interaction, ranging, for example, from poorly integrated verbal and nonverbal communication; to abnormalities in eye contact and body language or deficits in understanding and use of gestures; to a total lack of facial expressions and nonverbal communication.

3.       Deficits in developing, maintaining, and understanding relationships, ranging, for example, from difficulties adjusting behavior to suit various social contexts; to difficulties in sharing imaginative paly or in making friends; to absence of interest in peers.

Specify current severity:

Severity is based on social communication impairments and restricted repetitive patterns of behavior (see Table 2).

B.      Restricted, repetitive patterns of behavior, interests, or activities, as manifested by at least two of the following, currently or by history (examples are illustrative, not exhaustive; see text):

1.       Stereotyped or repetitive motor movements, use of objects, or speech (e.g., simple motor stereotypies, lining up toys or flipping objects, echolalia, idiosyncratic phrases).

2.       Insistence on sameness, inflexible adherence to routines, or ritualized patterns or verbal nonverbal behavior (e.g., extreme distress at small changes, difficulties with transitions, rigid thinking patterns, greeting rituals, need to take same route or eat food every day).

3.       Highly restricted, fixated interests that are abnormal in intensity or focus (e.g, strong attachment to or preoccupation with unusual objects, excessively circumscribed or perseverative interest).

4.       Hyper- or hyporeactivity to sensory input or unusual interests in sensory aspects of the environment (e.g., apparent indifference to pain/temperature, adverse response to specific sounds or textures, excessive smelling or touching of objects, visual fascination with lights or movement).

Specify current severity:

Severity is based on social communication impairments and restricted, repetitive patterns of behavior (see Table 2).

C.      Symptoms must be present in the early developmental period (but may not become fully manifest until social demands exceed limited capacities, or may be masked by learned strategies in later life).

D.      Symptoms cause clinically significant impairment in social, occupational, or other important areas of current functioning.

E.       These disturbances are not better explained by intellectual disability (intellectual developmental disorder) or global developmental delay. Intellectual disability and autism spectrum disorder frequently co-occur; to make comorbid diagnoses of autism spectrum disorder and intellectual disability, social communication should be below that expected for general developmental level.

Note: Individuals with a well-established DSM-IV diagnosis of autistic disorder, Asperger’s disorder, or pervasive developmental disorder not otherwise specified should be given the diagnosis of autism spectrum disorder. Individuals who have marked deficits in social communication, but whose symptoms do not otherwise meet criteria for autism spectrum disorder, should be evaluated for social (pragmatic) communication disorder.

Specify if:
With or without accompanying intellectual impairment
With or without accompanying language impairment
Associated with a known medical or genetic condition or environmental factor
(Coding note: Use additional code to identify the associated medical or genetic condition.)
Associated with another neurodevelopmental, mental, or behavioral disorder
(Coding note: Use additional code[s] to identify the associated neurodevelopmental, mental, or behavioral disorder[s].)
With catatonia (refer to the criteria for catatonia associated with another mental disorder, pp. 119-120, for definition) (Coding note: Use additional code 293.89 [F06.1] catatonia associated with autism spectrum disorder to indicate the presence of the comorbid catatonia.)

Table 2  Severity levels for autism spectrum disorder

Severity level Social communication Restricted, repetitive behaviors
Level 3
“Requiring very substantial support”
Severe deficits in verbal and nonverbal social communication skills cause severe impairments in functioning, very limited initiation of social interactions, and minimal response to social overtures from others. For example, a person with few words of intelligible speech who rarely initiates interaction and, when he or she does, makes unusual approaches to meet needs only and responds to only very direct social approaches
Inflexibility of behavior, extreme difficulty coping with change, or other restricted/repetitive behaviors markedly interfere with functioning in all spheres. Great distress/difficulty changing focus or action.
Level 2
“Requiring substantial support”
Marked deficits in verbal and nonverbal social communication skills; social impairments apparent even with supports in place; limited initiation of social interactions; and reduced or  abnormal responses to social overtures from others. For example, a person who speaks simple sentences, whose interaction is limited  to narrow special interests, and how has markedly odd nonverbal communication.
Inflexibility of behavior, difficulty coping with change, or other restricted/repetitive behaviors appear frequently enough to be obvious to the casual observer and interfere with functioning in  a variety of contexts. Distress and/or difficulty changing focus or action.
Level 1
“Requiring support”
Without supports in place, deficits in social communication cause noticeable impairments. Difficulty initiating social interactions, and clear examples of atypical or unsuccessful response to social overtures of others. May appear to have decreased interest in social interactions. For example, a person who is able to speak in full sentences and engages in communication but whose to- and-fro conversation with others fails, and whose attempts to make friends are odd and typically unsuccessful.
Inflexibility of behavior causes significant interference with functioning in one or more contexts. Difficulty switching between activities. Problems of organization and planning hamper independence.