What Are The Biological Causes For Mental Retardation?

Can MRI detect mental retardation?

MRI allows detection of multiple minor morphological anomalies.

Most have classically been considered as normal variants but they may in fact be markers of cerebral dysgenesis and are currently the only anomaly detected in the work-up of patients with mental retardation..

What does it mean to have mild mental retardation?

Definition. Mild mental retardation is defined as significantly subaverage intellectual ability, which ranges between 50–55 and 70, and concurrent delays in adaptive functioning that present prior to the age of 18.

What is the common type of chromosomal abnormality associated with mental retardation?

X-linked forms of mental retardation are estimated to cause 10-20% of all inherited cases of mental retardation. The first gene to be identified was FMR1 that causes fragile X syndrome and still remains the commonest single gene abnormality to be identified.

Can mental retardation be reversed?

“The same mutation in animals produces learning disorders, which we were able to eliminate in adult mice. Our work and other recent studies suggest that some forms of mental retardation can be reversed, even in the adult brain.”

What is the life expectancy of someone with mental retardation?

As the table shows, children or adults with profound, severe, or suspected retardation who were immobile, not toilet-trained, and tube-fed had a very low life expectancy and usually died within four years.

Is mental retardation a genetic disorder?

Mental retardation is caused by a number of different factors. Among genetic disorders, Fragile X syndrome and Down syndrome are the commonest causes of mental retardation. Fragile X syndrome (FXS) is an inherited form of mental retardation. FXS is estimated to affect 1 in 2,500 males and 1 in 8,000 females.

Is ADHD an intellectual disability?

Some mental health, neurodevelopmental, medical and physical conditions frequently co-occur in individuals with intellectual disability, including cerebral palsy, epilepsy, ADHD, autism spectrum disorder and depression and anxiety disorders.

Does mental retardation get worse with age?

What mental changes occur, as adults with mental- retardation grow older? Like the general population after age 50, people with mental retardation, who do not have Down syndrome, experience a gradual decline in overall intellectual capacity, a decrease in their speed of recall, and slower general cognitive functioning.

Is Autism Genetic?

Autism has a strong genetic basis, although the genetics of autism are complex and it is unclear whether autism spectrum disorder (ASD) is explained more by multigene interactions or by rare mutations with major effects.

What are the genetic causes of mental retardation?

Specific examples of metabolic disorders with prominent MRDD include phenylketonuria, maternal phenylketonuria, Lesch-Nyhan, galactosemia, and adrenoleukodystrophy. o Down Syndrome is the leading genetic cause of mental retardation, occurring in about 1/800-1000 births.

What is the leading cause of mental retardation in newborns?

Fetal alcohol syndrome is now leading cause of mental retardation.

How can we prevent mental retardation?

7 Tips to Prevent Mental RetardationFind Out About Down Syndrome. … Promptly Treat Phenylketonuria (PKU) … Abstain From Alcohol During Pregnancy. … Help Your Kid Avoid Lead Poisoning. … Stay Healthy During Pregnancy. … Report Child Abuse and Neglect.

What are the 4 levels of mental retardation?

The DSM-IV classifies mental retardation into four stages based on severity: mild (IQ score of 50-55 to approximately 70), moderate (IQ score of 30-35 to 50-55), severe (IQ score of 20-25 to 35-40), and profound (IQ score of less than 20-25).

What are the types of mental retardation?

Mental retardation comprises five general categories: borderline, mild, moderate, severe and profound. Categories are based on scores obtained through use of age-standardized tests of cognitive ability (Table 1).

How can you tell if a baby has mental retardation?

Signs may appear during infancy, or they may not be noticeable until a child reaches school age. It often depends on the severity of the disability. Some of the most common signs of intellectual disability are: Rolling over, sitting up, crawling, or walking late.

What is the most common chromosomal abnormality?

aneuploidyThe most common type of chromosomal abnormality is known as aneuploidy, an abnormal chromosome number due to an extra or missing chromosome. Most people with aneuploidy have trisomy (three copies of a chromosome) instead of monosomy (single copy of a chromosome).

Is Autism considered an intellectual disability?

About 1% of the general population is thought to have intellectual disability, and about 10% of individuals with intellectual disability have Autism Spectrum Disorder (ASD) or autistic traits. However, a much higher percentage of individuals with ASD have intellectual disability3.

Why does phenylketonuria cause mental retardation?

Mutations in the PAH gene can cause phenylketonuria (PKU), a disorder that can change cells in the brain. The faulty protein allows dangerously high levels of phenylalanine to accumulate in the brain, poisoning the cells. If a person with PKU consumes too much phenylalanine, the build-up can cause mental retardation.

Does Klinefelter syndrome cause mental retardation?

Klinefelter syndrome (KS) has not typically been associated with mental retardation (MR), however, in recent years a growing body of evidence suggested that KS boys often experience language deficits and academic difficulties.

What is the most common cause of mental retardation?

Down’s syndrome is the most common specific cause of mental retardation, followed by the Fragile X syndrome, which mainly affects boys.

At what age is mental retardation diagnosed?

When is the diagnosis made? The onset of mental retardation is in childhood, before 18 years of age. The diagnosis is generally made after infancy, between the preschool and school-age periods. Sometimes the diagnosis may be made later, at the time when a thorough assessment is performed.