Mental Retardation

Types, Causes and Symptoms

Mental retardation is a condition in which a person’s ability to learn and function is limited than others of the same age group. The child may be considered a bit slow during infancy and the early years of childhood although the delays in development, language and motor skills may be apparent.

The emergence of this type of disorder is made only when the child faces problems with academic skills. Mental retardation is the condition that is diagnosed before the age of 18 years and includes below-average intellectual capacity and a lack of skills needed for everyday living.

Mental Retardation is nowadays termed as Intellectual Disability. There are various types such as Down’s syndrome, Phenylketonuria, Cretinism, Cranial Anomalies, Microcephaly and Hydrocephalus. Down’s syndrome is the most common form of mental retardation which is caused due to chromosomal anomalies. It is a genetic disorder and can affect anyone.

The physical characteristics of a person with Down’s syndrome is very visible such as almond shaped slanting eyes, thick skin on eyelids, flat and broad face and nose, large head and tongue, short neck, stubby fingers and speckled iris of the eyes. Phenylketonuria is a rare metabolic disorder where brain damage occurs along with moderate to severe intellectual functioning. In cretinism, the thyroid fails to develop and may occur due to birth injuries.

Cranial anomalies include macrocephaly, where there is an increase in size of head and brain; microcephaly, resulting from impaired brain development and failure to attain normal size; and hydrocephalus where damage occurs to the brain tissues and enlargement of the skull.

The degree of impairment from mental retardation varies from profoundly impaired to mild to borderline retardation. Some of the causes for this condition are present and occurs at or after birth. Most of them are chromosomal abnormalities while others are genetic abnormalities and inherited metabolic disorders. Some rare causes of mental retardation are nutritional in nature such as malnutrition; toxic in nature such as lead poisoning or exposure to drugs; trauma, such as head injury, etc.

The most common symptoms of mental disorder are continued infant-like behavior, decreased learning ability, failure to meet the markers of intellectual development, inability to meet educational demands at school, lack of curiosity, delays in achieving developmental, academic and social milestones, etc.

People with mild mental retardation develop social and communication skills during pre-school years and have limited impairment in sensorimotor skills. They are capable of achieving social and vocational skills required for minimal self-support but may need supervision, guidance and assistance.

In moderate mental retardation, people acquire basic communication skills but they profit from vocational training and moderate supervision for personal care. They can benefit from training in social and occupational skills but are unable to progress beyond second grade academics. They can perform unskilled work under supervision yet adapt well to community life in supervised settings.

Those with severe mental retardation acquire little or no communicative speech but may learn to talk and trained in self-care skills. Their academic skills are limited and may perform little tasks with supervision. Profound mental retardation is a neurological condition where there is slight impairment in sensorimotor functioning and development occurs with constant aid in a highly structured environment with continuous supervision and individualized relationship with a caregiver.