Down Syndrome Adapted from Hallahan, D.P., J. M., & Pullen, P. C. (2012). Exceptional learners: An introduction to special education (12th ed.). New Jersey, NJ: Pearson Education, Inc.
Causes Down syndrome is usually not an inherited condition. Down syndrome is the most common form of intellectual disability that is present at birth. It involves an irregularity at the 21st pair of chromosomes. The common case of Down syndrome is when the 21st set of chromosomes is a triplet rather than a pair, which is commonly referred as trisomy 21. (Humans usually have 23 pairs of chromosomes.)
Prevalence According to the Health Promotion Board (2012), 1 out of every 700 babies is affected by the chromosomal disorder.
Down Syndrome Adapted from Hallahan, D.P., J. M., & Pullen, P. C. (2012). Exceptional learners: An introduction to special education (12th ed.). New Jersey, NJ: Pearson Education, Inc.
Psychological and Behavioral Characteristics: Physical characteristics •
May have thick eyelid folds in the corner of the eye (making eyes appear slant upwards slightly)
•
Have a small physique, decreased muscle tone (hypotonia) and flexibility of the joints
•
With a small oral cavity that can result to protruding tongue, short and broad hands with single palmar crease, heart defects and susceptibility to upper respiratory infections
Behavioural characteristics •
Often lacks of motivation and will tend to look for external form of motivation
•
May face difficulty making friends due to their inappropriate behaviour and the lack of awareness to respond to social situations.
Down Syndrome Adapted from Hallahan, D.P., J. M., & Pullen, P. C. (2012). Exceptional learners: An introduction to special education (12th ed.). New Jersey, NJ: Pearson Education, Inc.
Psychological and Behavioral Characteristics: Psychological characteristics •
Deficits in attention, memory, language, self-regulation, motivation and social development
•
Have difficulty allocating their attention properly
•
Widespread memory difficulties and often problem with working memory
•
Have limitations in language comprehension and production.