Intellectual Disability: Meaning, Causes, Signs, Symptoms, Management


Intellectual disability is a health condition characterized by abnormal mental and psychological ability of a person that begins during infancy. These children have the potential of learning new skills, but at a slower rate than the normal children (Harris, 2010). Therefore, these children have a limited ability to reason, learn, make proper decisions, and solve problems in their lives. The children with intellectual disability also find it challenging to manage adaptive behavior skills such as communicating effectively and interacting with each other or even to take good care of themselves (Yen, Kung, Chiu, & Tsai, 2014). This research paper analyzes the meaning, the causes, the signs and symptoms, and the management of intellectual disability.

Meaning of Intellectual disability

According to Harris (2010), intellectual disability can be determined by factoring in the infant IQ levels. The average IQ of a normal child is 85 to 115 on the IQ test. However, the children suffering from intellectual disability usually score less than 75 on the IQ test. The other tests for intellectual disability are the Abnormal Denver developmental screening tests and the Adaptive behavior test (Goddard, Davidson, Daly, & Mackey, 2008). The adaptive behaviors are also analyzed by observing a child’s skills and comparing it with other children of the same age. About 1% of the population suffer from the intellectual disability. About 85% these few cases experience mild intellectual disability (Iocono et al, 2014). Therefore, they can learn new skills and live independently later in life if provided with appropriate support. Intellectual disability is caused by any condition or situation that may interfere with usual brain development. Most of the factors that cause intellectual disability by interfering with brain development are genetic conditions such as Down syndrome and complications associated with pregnancy. With proper care, the persons with intellectual disability can live the good life in the society. However, the persons with intellectual disability are also likely to be victimized due to several reasons as summarized by the chart shown below.

Causes of intellectual disability

Researchers have unearthed several possible causes of intellectual disability. These causes have been broadly categorized as genetic causes, problems during pregnancy, and problems during birth, problems after birth, and poverty and cultural deprivation (Harris, 2010).

In terms of genetic causes, researchers have established that it is possible to inherit the intellectual disability from the gene of the parents. The disease can also result from the disorders of the genes.  Other genetic diseases such as phenylketonuria are also associated with genetic disorders. These children with disorders cannot effectively process part of the protein known as phenylalanine within their brain, making them to develop intellectual disability. Chromosomal disorder such as the Down syndrome also causes intellectual disability when there are either too many or too few chromosomes (Tuffrey-Wijne et al, 2014).

According Harris (2014), intellectual disability can also be caused by problems during pregnancy. When the pregnant mother uses alcohol or drugs during pregnancy, the chemical composition of these products can distort the smooth brain development of the child and the subsequent intellectual disability. Currently, researchers estimate that alcohol consumption is the leading preventable cause of intellectual disability. Malnutrition of the mother, continued exposure to some environmental toxins, and sickness can also make a pregnant mother to conceive a child with intellectual disability. On the same note, the children who are born prematurely are also at high risk of intellectual disability. Children who have experienced difficulties during birth process such as temporary deprivation of oxygen are also at high risks of intellectual disability.

Even after birth, a child is still at risk of developing intellectual disability (Harris, 2014). The diseases that affect children like the chicken pox, whooping cough, measles, and meningitis among others have the potential of interfering with the brain development and causing intellectual disability. Children exposed to lead and mercury toxicities can also develop intellectual disability due to their damaged brain.

Signs and Symptoms

There are signs that are linked to intellectual disability. However, most of these signs may not be noticed until the child reaches the school going age. One of the most common signs and symptoms of intellectual disability in infants is associated with rolling over, crawling, sitting up, and walking and talking later than other normal kids (Goddard, Davidson, Daly, & Mackey, 2008). Such kids are also slow to master basic things like self-feeding, potty training, and dressing. Infants with intellectual disability also find it hard to comprehend the consequences of their actions. In most cases, these children portray the difficulty in logical thinking and seem to lack problem solving skills. On the other hand, the children with intellectual disability are also linked with behavioral problems such as explosive tantrums. Those infants with severe intellectual disability are also associated with other health problems such as mood orders, seizures, vision problems, motor skills impairment, and hearing problems.

Management of Intellectual disability

Advances in scientific research in the past 30 years have supported the management of intellectual disability. Treatment for intellectual disability involves developing the child’s potential to the fullest to enable him match with his peers. Therefore, special education is recommended for children with intellectual disability (Harris, 2014). However, this is done after the specialist has carefully evaluated the child’s physical and mental problems before being subjected to behavioral counseling. Therefore, management of intellectual disability is a long process that should be initiated before the infants are born, immediately the infants are born, and most parts of their early lives.

Prenatal care

Management of intellectual disability can perfectly be done during prenatal care, since the health of the infant is highly dependent on the health of the mother. Therefore, the mother should be updating immunizations to ensure that the fetus remains healthy (Goddard, Davidson, Daly, & Mackey, 2008). In addition, the mother should review the use of medications and consume a balanced diet and vitamins to enhance the health of the fetus. Also, the pregnant mother should cease to use tobacco, alcohol, cigarettes, and other forms of illegal drugs that are not prescribed by the doctor. Prenatal care should be observed immediately during pregnancy and the mother should ensure that she gets enough rest and sleep during the same period. The mother should consider genetic counseling of there are previous cases of intellectual disability within the family.

Post natal care

Intellectual disability can also be managed after the child birth. Immediately the child is born, the mother should take the child for newborn screening for early diagnosis and prevention of any possible genetic disease. The mother should constantly take the infant baby to undergo child immunizations to protect the infant from diseases that may interfere with brain development (Yen, Kung, Chui, & Tsai, 2014). The mother should also protect and monitor the child movement to prevent possible injury to the brain. In addition, the mother should constantly ensure that the infant is not exposed to environmental hazards such as mercury, lead, and other toxins that interfere with brain development.

Teaching methods for children with intellectual disability

One of the teaching methods for children with intellectual disability is to break the learning tasks into small groups. It is until students have mastered one step that the next step is introduced. This method of learning ensures that the children are introduced into new concepts in accordance with their pace. Another strategy that can be used for people with intellectual disabilities is modifying all the teaching approaches to ensure that the disabled persons get the right education. In this method, the teachers can work to explain concepts like gravitational pull by dropping something for the disabled students to understand better. On the same note, people with intellectual disability tend to perform much better in learning environments accompanied by visual aids. The visual aid materials make learning much simpler for persons with learning disabilities.

            Another teaching strategy for the persons with intellectual disability is by making sure that they are provided with direct as well as immediate feedback. In most cases, persons with intellectual disabilities require immediate feedback that helps them know and rectify their abnormal behaviors. It is through such feedback that such individuals are able to make a better connection between their behavior and the response they get from their teachers. Moreover, a delay in providing the required feedback makes it much difficult for such individuals to form a connection between the cause and effect of their learning, leading to a misinformation.


In conclusion, intellectual disability is a serious condition that interferes with the infants’ ability to live a normal life like their peers. The causes of intellectual disability have been broadly categorized as genetic causes, problems during pregnancy, and problems during birth, problems after birth, and poverty and cultural deprivation.  Treatment for intellectual disability involves developing the child’s potential to the fullest to enable him match with his peers. Therefore, special education is recommended for children with intellectual disability.


Goddard, L., Davidson, P. M., Daly, J., & Mackey, S. (2008). People with an intellectual disability in the discourse of chronic and complex conditions: An invisible group? Australian Health Review, 32(3), 405-14.

Harris, J.C. (2010), Intellectual Disability: A Guide for Families and Professionals. Oxford University Press; 1 edition

Iacono, T., Bigby, C., Unsworth, C., Douglas, J., & Fitzpatrick, P. (2014). A systematic review of hospital experiences of people with intellectual disability. BMC Health Services Research, 14, 505. doi:

Tuffrey-Wijne, I., Goulding, L., Gordon, V., Abraham, E., Giatras, N., Edwards, C., & Hollins, S. (2014). The challenges in monitoring and preventing patient safety incidents for people with intellectual disabilities in NHS acute hospitals: Evidence from a mixed-methods study. BMC Health Services Research, 14, 432. doi:

Yen, S., Kung, P., Chiu, L., & Tsai, W. (2014). Related factors and use of free preventive health services among adults with intellectual disabilities in Taiwan. BMC Health Services Research, 14, 248. doi:


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