Introduction to the Pervasive Developmental Disorders

Mental Retardation and Autism Spectrum Disorders

Pervasive developmental disorders were first introduced into the DSM III. Many refer to this diagnostic taxonomy as autism spectrum disorder (ASD) because both are depicted as disorders affecting a child’s social, communicative, emotional, and cognitive development; however, the current DSM-IV-TR strictly refers to them as Pervasive Developmental Disorder (PDD) (Hoffman, 2009). PDDs are classified as a group of conditions where there is a delay in the development of communication and social skills. Behavioral differences/problems are also present. Parents may notice that their children play with their toys differently than the other children do or that they make repetitive movements. Parents may also notice that their children are not “up to par” on the language level as they should be. The child may seem to lag behind others within their peer group in language production and comprehension. They might play alone instead of with the other children. This lack of socialism could be connected to the lack of communication. A child might just seem “shy” but in reality cannot produce language normally. Some children may talk a little or not at all, while others show only a small deficit in language skills. Individuals determined to have a PDD not only exhibit problems in social interaction and communication but may exhibit stereotyped behaviors, interests, and activities. The individual’s developmental level or mental age is considered to be deviant compared to that individual’s biological age. However, the individual’s intelligence may be difficult to gauge due to communication problems. Under PDD, the DSM-IV-TR holds five subtypes: autism, Asperger’s disorder, Rett’s disorder, childhood disintegrative disorder (CDD), and PDD-NOS (not otherwise specified). The key distinguishing features lie in how the domains are affected, the age of onset, gender differences, the course of the disorder, and prognosis (Hoffman, 2009).

  • High Prevalence of Pervasive Development Disorders
    • PDD, in children and adolescents, are among the most common and disabling disorders (Sasayama, 2009).
    • The high prevalence of these disorders have amplified the need to improve the management in children and adolescents (Sasayama, 2009).
    • New protocol guidelines have been implemented to assist primary care doctors to recognize the need for a mental health consultation if the PDD seems severe or if comorbities are present (Sasayama, 2009).
  • Comorbidity and Depression
    • Studies have shown emerging evidence that PDD patients are most likely to also carry depression with their disorder (Sasayama, 2009).
    • Children and adolescents who had such severe depression that it required medical treatment with antidepressants may be comorbid with PDD (Sasayama, 2009).
    • PDD symptoms must always be assessed when treating depression in children and adolescents (Sasayama, 2009).

Deficits in understanding the mental state of others or “mind-reading” have been well documented in individuals with pervasive developmental disorders. However, this deficit in social cognition differs between the subgroups of PDD defined by the Diagnostic and Statistical Manual of Mental disorder, Fourth Edition, Text Revision. PDD can be divided into high-functioning autistic disorder (HFA) and other PDD consisting of Asperger’s disorder and PDD-NOS. A recent study suggest that social cognition differs significantly between individuals with HFA and those with other PDD. Neither the auditory or visual modality was found to be dominant in subjects with PDD in the mind-reading task. Taken together, complex mind-reading tasks appear to be effective for distinguishing individuals with HFA from those with other PDD (Kuroda, Wakabayashi, Uchiyama, Yoshida, Koyama, & Kamio, 2011).

Treatments

There is no cure for Pervasive Developmental Disorders but there are treatments available to ease symptoms. Behavioral therapies are more common than medications due to the side effects of the drugs. There are some long-term adverse events caused by risperidone in children, adolescents, and adults with Pervasive Developmental Disorders and intellectual disability. One study examined the side effects of this treatment drug and found a range of significant neurological side effects had occurred: akathisia in 10%, 2 individuals developed tardive dyskinesia, 1 developed oculogyric crisis; withdrawal dyskinesia occurred in 2 of 9 individuals discontinuing risperidone. All children and adolescents in the study continued greater than 7% weight gain. Adults gained less weight, but 2 developed Type 2 diabetes. Movement side effects were also significant (Hellings, Cardona, & Schroeder, 2010).

Weighted vests are a specific form of Sensory Integration Therapy (SIT) (Honaker, 2005) that are intended to help individuals resolve sensory related issues thereby decreasing the symptoms (e.g., hyperness, lack of attention, etc.) of the sensory issue and are also often recommended as an intervention for problem behaviors exhibited by children with Pervasive Developmental Disorders (PDD). The effects of 5% and 10% total body weight vests on problem behaviors in children with PDD were investigated during functional analysis conditions (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994). Though results indicated there was no functional relationship between the SIT of 5% or 10% weighted vests and participants’ problem behaviors, a further analysis indicated there was a functional relationship between the problem behavior and the operant-based intervention of functional communication training. Thus, though the problem behaviors appeared to be unresponsive to SIT (i.e., weighted vests) these same problem behaviors could be altered with interventions that have been grounded in rigorous, empirical scientific research findings (Quigley, Peterson, Frieder, & Peterson, 2011).

Social skills deficits are a defining feature of individuals diagnosed with autism and other pervasive developmental disorders (PDD), which can impair functioning and put the individual at higher risk for developing problem behavior (e.g., self-injury, aggression). Adolescence with PDD often display inappropriate social behavior (inappropriate comments, social withdrawal, and touching others without their permission) during social interactions. An intervention using instructions, differential reinforcement, and corrective feedback has been shown to successfully reduced inappropriate social behaviors (Hagopian, Kuhn, & Strother, 2009).

Learning with Pervasive Developmental Disorders

Most Pervasive Developmental disorders contain learning deficits. The main problem with teaching children with Autism is accurate communication between the child and the instructor and maintaining the child’s attention. This is why most teaching techniques tend to be behaviorially focused instead of cognitive.

The Errorless Learning technique is a method of teaching focused on the reduction of incorrect answers. The examples of this are stimulus fading, stimulus shaping, delayed prompting, response prevention, superimposition with fading and superimposition with shaping. Stimulus fading is the gradual increasing the dimensions of the distracters (incorrect answers) to be similar to the target (correct answers). Stimulus shaping is making physical changes to the target and distracters over the trials such as gradually changing known letters into unknown letters over successive trials by changing their shape. Delayed prompting is the gradual delay of the onset of a prompt that identifies the target such as providing immediate indication of the target and then gradually delaying indication. Response prevention is physically preventing the learner from responding to the distracters such as physically blocking responses to the distracters until the learner responds independently to the target. Superimposition with fading is superimposing physical prompts and using stimulus fading such as adding pictures to accompany sight words cards and then gradually reducing the size until the pictures are no longer visible. Superimposition with shaping is superimposing physical prompts and using stimulus shaping such as teaching a child to respond to known pictures in the presence of unknown words and then changing the pictures gradually into the pictures of the unknown words.

The Competent Learner Model was developed to address the needs of teachers, administrators, and paraprofessional staff to enhance delivery of instructional programs and services for children and youth with pervasive developmental disabilities. The main focus of the Competent Learner Model is to teach learners to become competent observers, listeners, talkers, problem solvers, participators, readers, and writers. Simply put, it is a method that teaches learning-to-learn competencies. This method also has the common goals of behavioral interventions such as increasing attention, play, social, self-help, academic, and language skills and to decrease stereotypic, annoying, injurious, disruptive, and destructive behaviors. The Competent Learner Model is not only used in class rooms but is also suggested to be used by caretakers in the home. The seven parts of the Competent Learner Model that are focused on developing are skills in observing, listening, reading, writing, problem solving, and participating.

Visually cued instruction involves the use of pictographic and written language as instructional supports in both structured and natural learning contexts. People with Autism are known for their weaknesses in abstract thinking, social cognition, and communication. Visually cued instruction attempts to play on the strengths of people with Autism such as areas of concrete thinking, rote memory, and understanding of visuo-spatial relationships. Hermelin and O’Connor’s (1970) work on Autistic children’s ability to process visuo-spatial information and auditory-temporal information. They found that auditory-temporal information was much more difficult for Autistic children to process than visuo-spatial information. Experiments have shown that the more time a stimulus remained fixed in space improve the ability to encode and organize the information in children with Autism. Other works seem to agree with this finding by reveling that Autistic children perform best on tasks such as form discrimination, matching, copying exact duplications, and puzzle assembly, all of which involve visual stimuli that remain present at all times (DeMyer, 1975).

Durkin (2010) provided an accumulation of research from several studies that shed positive light on the advantages of learning via videogames for children diagnosed with Autism. Such studies “[exploit] the attraction of screen displays to children with autism, all the more notable given the difficulties with language development experienced by many children with this disorder” (Durkin, 2010). He pointed out that children with autism who took part in the experiments learned more words from a computerized game versus teacher instructions. Videogames may also provide a focus for peer discussion and the exchange of information amongst children with this disorder.