MENTAL RETARDATION DR SEDDIGH

Pre test Custodial MR ???? Severe MR ???? % Sex >>>>>> ???? Peer bahavior ???? Intellectual disability ????

HISTORY Mental retardation recognized perhaps longer than any other currently studied in psychology Written documents from ancient Egypt made oblique reference to the condition as early as about 1500 BC was often viewed as part of mental illness relatively common

Historical Treatment of MR Egypt 1500 B.C. Ancient Greece 200 A.D. Rome Middle Ages Reformation

Features of Mental Retardation DSM-IV Criteria significantly subaverage IQ (<70) concurrent deficits or impairments in adaptive functioning characteristics evident prior to age 18

Mental Retardation defined in the Diagnostic and Statistical Manual of Mental Disorders-IV as: significantly subaverage intellectual functioning: an IQ of approximately 70 or below concurrent deficits or impairments in present adaptive functioning in at least two of the following areas:communication, self-care, home living, social/interpersonal skills, use of community resources, self-direction, functional academic skills, work, leisure, health, and safety; and onset before age 18 years.   

Describing and Classifying Mental Retardation 5 DSM-IV-TR severity classifications for mental retardation

Mild – IQ of 50-55 to about 70 (Educable) Moderate – IQ of 35-40 to 50-55 (Trainable) Severe – IQ of 20-25 to 35-40 (Custodial) Profound – IQ below 20 or 25 (Custodial) Unspecified – presumption of mental retardation but intelligence not testable with standardized instruments

Mild Retardation Some 85% of all people with mental retardation fall into the category of mild retardation (IQ 50–70) They are sometimes called “educably retarded” because they can benefit from schooling typically not identified until elementary school years People with mild retardation typically need assistance but can work in unskilled or semiskilled jobs Intellectual performance seems to improve with age

Mild Retardation Research has linked mild mental retardation mainly to sociocultural and psychological causes, particularly: Poor and unstimulating environments Inadequate parent-child interactions Insufficient early learning experiences

Mild Retardation Although these factors seem to be the leading causes of mild mental retardation, at least some biological factors may also be operating Studies have linked mothers’ moderate drinking, drug use, or malnutrition during pregnancy to cases of mild retardation

Moderate, Severe, and Profound Retardation Approximately 10% of persons with mental retardation function at a level of moderate retardation (IQ 35–49) They can care for themselves and benefit from vocational training About 4% of persons with mental retardation display severe retardation (IQ 20–34) They usually require careful supervision and can perform only basic work tasks

Moderate, Severe, and Profound Retardation About 1% of persons with mental retardation fall into the category of profound retardation (IQ below 20) With training they may learn or improve basic skills but they need a very structured environment Severe and profound levels of mental retardation often appear as part of larger syndromes that include severe physical handicaps

Prevalence 1-3% of population (depending on cutoff) Slightly more males than females More prevalent in lower SES and in minority groups, especially for mild MR; no differences for more severe levels

Developmental Course Often children with mental retardation experience helplessness and frustration in their learning environments, which leads to low expectations and limited success With appropriate training and opportunities, children who have mild mental retardation may develop good adaptive skills in other domains

Language and Social Development Expressive language development may be weak in children with Down syndrome Fewer signals of distress or desire for proximity with primary caregiver, which can influence attachment Self-recognition often delayed, but positive Problems in the development of self-other understanding Deficits in social skills and social-cognitive ability; can lead to rejection by peers

Emotional and Behavioral Problems Emotional and behavioral disturbances four times greater than the general population Impulse control problems, anxiety problems, and mood problems common ADHD-related symptoms also common Pica and self-injurious behavior also common among those with severe and profound MR

Other Disabilities Associated with MR Can be associated with other pervasive physical and developmental disabilities, including sensory impairments, cerebral palsy, and epilepsy Chance of other disability increases as degree of intellectual impairment increases

Other Disabilities Associated with MR (cont.)

Etiology The causes of mental retardation are many and varied In some cases, pathology of a physiological or biological nature can be identified for as many as 30–40% of those with mental retardation, causation is unknown

Causes of MR Genetic Causes (65%) Chromosomal defects; Structural anomalies;Inborn errors of metabolism   Intrauterine Risk Factors (15%) Asphyxia; Developmental defects; Malnutrition/ Intrauterine growth retardation Maternal infections or diseases; Maternal substance abuse  Perinatal Risk Factors (10%):Anoxia; Birth trauma;Low birth weight;Prematurity Neonatal and Postnatal Causes (10%):Childhood infections and diseases; Environmental toxins; Severe malnutrition, Trauma 

Causes of Mental Retardation Many organic causes have been discovered but majority of cases cannot be explained, especially for mild mental retardation The two-group approach: organic mental retardation- includes chromosome abnormalities, single gene conditions, and neurobiological influences cultural-familial mental retardation- includes family history of mental retardation, economic deprivation, inadequate child care, poor nutrition, and parental psychopathology

Causes of Mental Retardation (cont.) Inheritance and the Role of the Environment heritability of intelligence is approximately 50% prenatal influences may be mistaken for genetic when they are actually environmental

Causes of Mental Retardation (cont.)

Causes of Mental Retardation Genetic and Constitutional Factors chromosomal abnormalities are the most common cause of severe MR Down syndrome due to an additional 21st chromosome Fragile-X syndrome, the most common cause of inherited MR, is associated with the FMR-1 gene Prader-Willi and Angelman syndromes both associated with abnormality of chromosome 15; believed to be spontaneous genetic birth defects occurring around the time of conception inborn errors of metabolism (referred to as single-gene conditions) can result in syndromes such as PKU

Causes of Mental Retardation (cont.) Neurobiological influences adverse biological conditions (e.g., malnutrition, exposure to toxins, Rubella, prenatal and perinatal stressors) infections, traumas, and accidental poisonings during infancy and childhood prenatal alcohol exposure can lead to a Fetal Alcohol Spectrum Disorder (FASD) Social and Psychological influences deprivation of physical and emotional care and social stimulation particularly influential

Genetic Factors Down syndrome three types of Down syndrome, each resulting from a different type of chromosomal error. Nondisjunction Translocation Mosaicism

Mental Retardation: Trisomy 21 Distinctive facial features Mild MR Parental age Medical complications

Mental Retardation: Fragile X Physical characteristics Females vs. Males Autism

Genetic Factors phenylketonuria (PKU), an inherited metabolic disorder that occurs in about 1 of every 10,000 live births Affected infants lack the ability to process phenylalanine, severely damages the central nervous system

Mental Retardation: PKU (genetic) Phenylalanine metabolizing deficiency MR Restricted diet

Genetic Factors Maple syrup urine disease Affected infants tend to excrete urine that has a distinctive odor of maple syrup may cause severe intellectual impairment, although more often than not the condition is fatal cause of this condition has been linked to metabolic deficiencies of three separate amino acids causing extreme CNS damage in the newborn Untreated maple syrup urine disease is fatal; few untreated infants survive more than a few weeks

Genetic Factors Galactosemia involves difficulty in carbohydrate (sugar) metabolism, rather than amino acid metabolism Infants with galactosemia are unable to properly process certain sugar components in milk Results are toxic damage to the infant’s liver, brain, and other tissues

Prevention, Education, Treatment Child’s overall adjustment is a function of parental participation, family resources, social supports, level of intellectual deficit, temperament, and other specific deficits Treatment involves a multi-component, integrated strategy that considers children’s needs within the context of their individual development, family and institutional setting, and community Prenatal education and screening may prevent some cases of MR

Treatment of children with mental retardation Three types of prenatal intervention Chromosomal analysis for Down Syndrome or other genetic abnormalities may result decision to abort fetus Treatment for Rh blood incompatibility between mother and fetus may prevent fetal damage. Prenatal identification of a PKU problem may result in maternal dietary restrictions

Prevention, Education, Treatment (cont.) Risk and protective factors affecting the psychological adjustment of intellectually disabled children

Prevention, Education, Treatment (cont.) Psychosocial treatments intensive, child-focused, early intervention efforts are very promising (particularly for disadvantaged children) optimal timing for intervention is in the preschool years behavioral techniques include shaping, modeling, graduated guidance, and social skills training cognitive-behavioral techniques, such as self-instructional training and metacognitive training family oriented interventions help families cope with the demands of raising a child with MR

Postnatal Interventions Infant stimulation programs provide positive developmental environment for very young children who are at risk because of prenatal or later environmental circumstances Specific instruction for young children in language skills appears promising and probably should be implemented as early as possible Inclusion of young children of school age in classrooms with non disabled peers

“Intellectual Disabilities” adopted by Continuous name shift “Mental Retardation” and “Learning Disabilities” are outdated and unacceptable for users “Intellectual Disabilities” adopted by IASSID / AAMR US President´s Commission DSM-IVTR 2005

Post test Custodial MR ???? Severe MR ???? % Sex >>>>>> ???? Peer bahavior ???? Intellectual disability ????

WITH THANKS DR SEDDIGH