Forgetting what is taught in the classroom, difficulty in following the teacher’s instructions and difficulty in attending to a specific task can suggest a diagnosis of Intellectual Developmental Disorder (IDD), formerly known as Mental Retardation. It is a disorder in which the child’s intellectual/mental functioning is impaired (along with other symptoms).
How is IDD defined?
Intellectual Developmental Disorder (IDD) is a neuro-developmental disorder originating during an individual’s developmental phase. It is characterized by significant limitations in:
Intellectual functioning (general mental capacity such as learning, reasoning, problem solving, judgment, academic learning, and abstract thinking)
Adaptive behavior (social and practical adaptive skills). For instance, the individual may have difficulty in learning a new skill, planning future tasks, or judging appropriate social behavior. Deficits in these abilities lead to impairment in social functioning such as interpersonal communication, social engagement. It also leads to impairment in activities of daily living such as dressing oneself, cooking, and money management.
IDD is classified under the Neuro-developmental Disorders section of the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) (Johns Hopkins Psychiatry Guide http://www.hopkinsguides.com/hopkins). The DSM-5 classifies IDD according to varying degrees (mild, moderate, severe, profound) in the following domains:
Conceptual (academic skills involving reading, writing, mathematics, time, money; executive function involving planning, strategizing, priority setting; short-term memory; and functional use of academic skills for instance, reading, telling the time).
Social (understanding social cues, social interaction, social judgment, social communication).
Practical (ability to perform daily living tasks, household tasks, vocational skills).
The term ‘Intellectual Disability’ is an equivalent for the diagnosis of ‘Intellectual Developmental Disorder’ and is more commonly used (Diagnostic and Statistical Manual of Mental Disorders, 5th Edition)
What does it mean?
Children with IDD have below-average intelligence. Children with IDD learn more slowly than typically developing children. This learning deficit applies to learning across developmental phases and across many skills. For instance, children with IDD may learn to sit up, crawl, walk, and talk later than typically developing children. Most children with IDD also face deficits in their communication skills, and their ability to interpret and apply new information – they find it difficult to communicate their wants and needs. As a result, such children often find it hard to keep up with their peers in school (Child Mind Institute http://childmind.org/guide/intellectual-development-disorder/).
Older children with IDD may show deficits in memory, social and problem-solving skills. Some children may also show a lack of social inhibitions – that is, he/she may act inappropriately or say socially inappropriate things in public. They are not able to understand what behaviors are socially appropriate/acceptable in a given situation and hence might say or do things that come across as inappropriate, rude, or rebellious (Child Mind Institute http://childmind.org/guide/intellectual-development-disorder/).
Children with IDD also often have difficulty with adaptive skills – they are unable to perform tasks necessary for day-to-day living (activities of daily living) independently. They struggle with taking care of themselves. In most cases, individuals with IDD require assistance with activities of daily living.
Standardized tests such as an IQ test can be used to determine a child’s intellectual development. A score below 70 on a standardized IQ test would indicate that the child may have IDD. A key area to be observed before officially diagnosing a child is his/her adaptive behavior such as his/her interpersonal skills, communication skills, and daily living skills such as grooming, using the bathroom independently (Child Mind Institute http://childmind.org/guide/intellectual-development-disorder/)
IDD is not a disease and hence cannot be ‘cured’ but early diagnosis and intervention can improve adaptive functioning (Millcreek Behavioral Health Treatment Center http://www.millcreekofmagee.com/). IDD can be tackled through the intervention programs including Special Education, Speech Therapy, Occupational Therapy, and family counseling aimed specifically at helping children learn adaptive skills so that they can live independent lives.