Cognitive Deficits

Cognitive deficits (intellectual disability) are a condition beginning in childhood showing significant limitations in the ability to learn and function.

Cognitive deficits, also called intellectual disability, are a condition beginning in childhood in which people show significant limitations in their ability to learn and function.

• The two systems most commonly used to categorize individuals with intellectual disabilities are those adopted by the American Association on Intellectual and Developmental Disabilities (AAIDD) and the American Psychiatric Association (DSM-IV-TR).
• The DSM-IV subdivides individuals with intellectual disability into degrees of severity based on their level of impairment (mild, moderate, severe, or profound) in intellectual functioning, while the AAMR classifies individuals on their ability to function in an inclusive environment and defines the degree of severity (intermittent, limited, extensive, or pervasive) based on the patterns and intensity of support needed.

• About 5% of the population has cognitive deficits, and most of these individuals fall into the mild range deficit category.
• Sometimes, children with attention deficits, learning disabilities, communication disorders, or pervasive developmental disorders may be thought to have an intellectual disabilities.
• To make a correct diagnosis, all children with a pattern of delayed or abnormal development or learning should undergo comprehensive psychoeducational testing.
• Psychologist diagnoses a cognitive deficit through several tests including the IQ test, the Bayley scales of infant development, the Stanfor-Binet Intelligence scale, and the Wechsler Intelligence Scale for Children.

• Genetic counseling might be useful in family planning and in identifying hereditary conditions that may cause cognitive deficits.

• Early in childhood, a parent or other caregiver might notice that a child has a global developmental delay (delays in all areas of development, including language, walking, self-care skills, and/or imitative play). Children with more severe impairments or those with obvious dysmorphic features are often identified in the first year of life.
• Some parents may only notice a delay in their child after a younger sibling catches up developmentally to the child with the developmental delay.
• In other instances, the child might first demonstrate behavioral issues (such as difficulty toilet training), that may ultimately come to the attention of a medical professional and be found to be related to delays in development.
• With less significant impairments, the first sign of a cognitive deficit might be difficulties in school. For example, the child might have trouble learning to read and do the math.

Cognitive deficits do not have an identifiable cause in many people. However, with comprehensive evaluation, the specific cause of about a majority of cases of severe deficits can be identified.

The causes of cognitive disabilities are generally divided into prenatal, perinatal, and postnatal factors.

• Prenatal causes (those that occur before birth) may include genetic abnormalities, infections, exposures to substances that cause birth defects, and central nervous system malformations, Down syndrome and fragile X syndrome are among the most common genetic causes of intellectual disability.
• Perinatal causes (those occurring around the time of birth) may include fetal malnutrition, prematurity, and decreased oxygen to the brain.
• Postnatal or acquired causes (those after the newborn period) may include trauma (accidental and nonaccidental), suffocation, infections, toxic digestions, brain damage, central nervous system tumors or cancer, degenerative disorders, and environmental influences (psychosocial deprivation, severe malnutrition).

Developmental delays

A child should be evaluated as soon as a developmental delay is suspected. The Individuals with Disabilities Education Act (IDEA) mandates that all children have the right to an appropriate education regardless of any disabilities they might have.

Thus, for children aged birth to three years of age with a developmental delay, each state has a program that evaluates and treats them for free. For children older than three years of age, the individual school districts are responsible for the child's evaluation and treatment. Children may be evaluated in the following skill areas:

• Social-emotional
• Adaptive (ability to adjust to changes)
• Cognitive (awareness and judgment)
• Language
• Gross motor (control of large movements)
• Fine motor (control of small movements)

Early evaluations can detect developmental delays and lead to the provision of intervention services. These services are designed to assist children in building skills during this time of greatest brain development.

In addition to a psychoeducational evaluation, the child with developmental delays should have a medical evaluation. In some cases, a specific cause for cognitive impairment may be identified. If a cause is found, there may be health implications for the child, family planning issues, or both.

For example, fragile X syndrome is a condition that usually develops in boys and is associated with cognitive deficits that are inherited from the child's mother. Girls can also be affected, but they are usually carriers, meaning that they could pass on the condition to their children.

Behavioral issues

Both children and adults with cognitive deficits have a higher risk of both psychiatric disorders and behavioral problems than people in the general population. Treatment may be necessary for behavioral issues. For example, a child might have problems with the following:

• Attention
• Sleep
• Aggression
• Self-harming behaviors

Psychologists and other therapists can address some of these issues through behavioral modification. Other children might benefit from medications that may allow therapeutic and behavioral strategies to be more effective.

Children with cognitive deficits go through puberty at a similar age as their peers without cognitive deficits. During puberty, physiologic and emotional changes occur that are similar in both children with cognitive deficits and those without cognitive deficits.

However, a child with cognitive deficits has increased difficulty in coping with the social and emotional demands of puberty.

At this time, children with cognitive deficits may become more aggressive or oppositional. With girls, hormonal methods to manage menstruation and ease hygiene issues may be considered.

• Is my child's condition inherited? What is the risk that if I have another child, he or she will have the same condition?
• How can my child achieve his or her greatest potential?
• Where can I go to get my child started with early intervention services?
• Where can I go for additional information and assistance?

A psychologist can diagnose a cognitive deficit by conducting a series of tests that assess the cognitive development of the child.

• IQ (intelligence quotient) test: IQ tests typically include an assessment of memory, language development, problem-solving, spatial ability, visual-motor skills, and mathematic reasoning. A test of intelligence does not produce a stable result until a child is six to eight years of age; cognitive tests can be administered before this time, but the scores should be interpreted with caution as the scores may change with age.
• Bayley Scales of Infant Development: This test might be used to assess development in infants.
• Stanford-Binet Intelligence Scale or the revised Wechsler Preschool and Primary Scale of Intelligence (WPPSI-R): These tests may be used to assess cognitive ability in preschoolers.
• Wechsler Intelligence Scale for Children (WISC-IV): This intelligence test is most commonly used to assess cognitive development in school-aged children.

In addition to cognitive testing, an assessment of adaptive function is necessary. The Vineland Adaptive Behavior Scales measure a child's level of independent functioning, providing a percentile score that compares the child to other children of similar age.

In addition to cognitive and adaptive function tests, a doctor might recommend a medical evaluation. This may include hearing and vision tests and lab tests, such as a blood lead level test, a screening for thyroid function, a high-resolution chromosome analysis, a DNA probe for fragile X syndrome, or all of the above.

An MRI of the brain may be necessary to look for differences in the brain that might help explain a cognitive deficit. Sometimes, a consultation with a geneticist might be helpful to determine if the child has a genetic syndrome and, if so, to help in family planning.

• Some children and adults with cognitive deficits might need only minimal support at home, while others with more significant deficits may need more help.
• A parent or caregiver should focus early on helping a child to develop skills to care for himself or herself.
• Knowing the developmental abilities of a child is helpful to ensure that learning and adaptive demands are reasonable and that appropriate supports are in place to help the child be successful.

No medical treatment exists for cognitive deficits; however, the following may be indicated:

• Nutritional interventions may be required for some individuals with specific disorders, including phenylketonuria, galactosemia, and maple syrup urine disease.
• Medications are commonly used in children and adults with intellectual disabilities to treat psychiatric disorders and behavior problems.
• A doctor may pay special attention to the common medical complications associated with specific disabilities (for example, cardiac, ophthalmologic, endocrine, orthopedic, and hematologic complications in Down syndrome).
• Some children with cognitive deficits have an increased risk of other medical problems including seizure disorders, sensory impairments (particularly visual deficits), cerebral palsy, feeding problems, and failure to thrive.

Symptoms of cognitive deficits such as aggression, sleep problems, attention deficits, and anxiety can be treated with medication in addition to behavioral approaches.

Medication is commonly used in children and adults with cognitive deficits for the treatment of psychiatric disorders as well as behavior problems. In general, medication therapy is used in combination with behavioral treatments and is considered to be only one component of a broad treatment plan.

Examples of such medications include the following:

• Attentional deficits: Stimulants such as methylphenidate (Ritalin) or dextroamphetamine
• Aggression, irritability, stereotypy: Clonidine, guanfacine, and antipsychotics such as risperidone
• Anxiety: BuSpar, bupropion (Wellbutrin), and SSRIs such as fluoxetine (Prozac) or sertraline (Zoloft) (SSRIs have recently received a black box warning from the US Food and Drug Administration. These medications may increase the risk of suicidal thinking and behavior in children and should be used with caution.)
• Sleep: Melatonin, clonidine

• A variety of therapists and services, including nursing services, occupational therapy, physical therapy, the use of adaptive equipment, speech-language therapy, nutritional counseling, audiology services, psychological intervention, recreation therapy, and social work services, can be used to treat the associated impairments sometimes seen with cognitive disabilities.
• Regular and special education teachers provide educational services. As adolescents and adults, individuals with cognitive disabilities may require employment services and work/vocational programs; access to social, recreational, and leisure activities (for example, Special Olympics); skills training; and assisted living services.
• Some of these services might be provided as a medical benefit or through the school system if an educational need is determined.

If a child has or may have a genetic syndrome, a periodic evaluation with a geneticist is useful to see if new syndromes or treatments have been discovered.

If a child is diagnosed with a developmental delay as a toddler or preschooler, a cognitive assessment is important when the child reaches school age to obtain an accurate IQ score.

• Genetic counseling might be useful in family planning and in identifying hereditary conditions that may cause cognitive deficits.
• Early and frequent prenatal care helps to ensure that fetal malnutrition does not occur. Prenatal care also helps to identify certain factors that might increase the risk of subsequent cognitive impairment such as prematurity and spina bifida.
• Ethanol-related birth defects represent the most common preventable form of intellectual disability for children in developed countries. Two to 5% of children in the United States have an FASD as a result of prenatal exposure to alcohol.

• The prognosis or outlook for a child with cognitive disabilities is highly individual and is influenced by a variety of psychological, medical, environmental, and cultural factors.
• Intellectual disability is not necessarily a life-long disorder. Some children with cognitive disabilities revealed by academic difficulties may, with appropriate services and interventions, develop adequate adaptive skills in other areas of functioning and no longer demonstrate the level of impairment required for a diagnosis of intellectual disability when they are an adult.
• The public continues to gain a greater awareness of cognitive disabilities and those affected by them. In 2005, the Individuals with Disabilities Education Act (IDEA) was reauthorized by Congress.
• Parents of children with cognitive deficits are often strong advocates for their children.

Parenting a child with a cognitive deficit can be emotionally challenging. The time of diagnosis, as well as transitional times, such as beginning school and graduating from high school, can be particularly difficult.

• Support groups, such as Families Together, can be useful. Families Together is an in-home social work program and an informational and training program. "The program provides training and information to enable individuals with disabilities, and their parents, family members, guardians, advocates, or other authorized representatives, to participate more effectively in meeting their vocational, independent living, and rehabilitation needs." Contact information may be obtained from each state's department of education or the Web site.
• Respite care is also important so that parents can spend time away from their children child and recuperate. Good respite care allows parents to feel confident that their child is being cared for appropriately in their absence.