Psychology Chapter: Intelligence and ADHD

Mental Retardation (MR)

• Mental retardation is replaced by the term intellectual developmental disorder.
• Intellectual disability is characterized by impaired cognitive and adaptive/social functioning.
• Severity level is based on adaptive functioning, indicating the degree of support required.
• The classical definition has 3 components:
  • Subaverage intellectual function
  • Resulting from an injury, disease or abnormality before age 18
  • Resulting in impaired ability to adapt to the environment
• Mental retardation is present in about 1% of the population.
• A single IQ score is not sufficient to determine intellectual disability severity.
• Intellectual disability severity is now determined using an IQ score of 70-75 or below and significant delays or lacks in least two areas of adaptive skills.
• IQ classification: (IQ -100; normal 90-110)
  • Borderline (IQ 70-80)
  • Mild (IQ 55-70)
  • Moderate (IQ 40-55)
  • Severe (IQ 25-40)
  • Profound (IQ below 25)

Etiology

• Unknown causes account for 30-40% of cases.
• Genetic causes account for approximately 5% of cases.
• Early embryonic (prenatal) causes account for 30% of cases.
• Perinatal causes (prematurity, IUGR) account for 10% of cases.
• Acquired medical conditions (trauma, infection) account for approximately 5% of cases.
• Environmental factors account for 5-20% of cases.

Cause Examples

• Genetic: Down syndrome (1/700 births), Fragile X syndrome, Phenylketonuria, Prader-Willi syndrome, Williams syndrome, Angelman syndrome, and tuberous sclerosis
• Prenatal: Toxoplasmosis, other infections (syphilis, AIDS), alcohol, illicit drugs, rubella, cytomegalovirus (CMV), and herpes simplex
• Perinatal: anoxia, prematurity, birth trauma and meningitis
• Postnatal: Hypothyroidism, malnutrition, toxin exposure and trauma

History

• Complete systemic review
• Surgical history (trauma, accidents)
• Medical history (illnesses, hospitalizations, pregnancies)
• Pregnancy history (maternal age, parity, infections)
• Birth history (type, weight, gestational age)
• Postnatal history (incubation, ventilator use, complications)
• Drug history (mother and child)
• Developmental history (milestones, speech/language, educational background)
• Behavioral history (skills, attention, activities, educational background)
• Family history (consanguinity, inherited disorders)
• Social history

Examination

• Growth parameters
• Dysmorphic features
• Central Nervous System (CNS) examination
• Examination of other systems and skin
• IQ tests
• Developmental testing

Diagnosis

• Deficits in intellectual functioning (reasoning, problem-solving, planning, abstract thinking, etc)
• Deficits in adaptive functioning (communication, social participation, independent living, etc)

Investigations

• Chromosomal study
• Amino-acid analysis in urine
• Mucopolysaccharide disorders evaluation
• Evaluation for reducing substances in urine (Galactosemia)
• Urine test for ferric chloride (phenylketonuria)
• Free T3, Free T4, TSH tests (hypothyroidism)
• Blood lead level
• Skull X-rays, brain CT, brain MRI, EEG
• Ammonia blood level
• Serum copper analysis
• Fundus examination
• Serological investigations
• Urine examination for ketoacids
• Neuro-enzymes evaluation
• Psychological studies
• Audiometry

Most Common Causes of MR

• Mongolism
• Cretinism
• Phenylketonuria
• Prenatal anoxia
• Post-encephaletic and post-meningitic conditions
• Congenital CP
• Hydrocephalus
• Microcephaly

Clinical Picture (Developmental, Educational, and Social)

• Delayed achievement of developmental milestones
• Infancy: delayed social development (social smile, delayed recognition of mother)
• Early Childhood: delayed speech, sphincteric control issues
• Late Childhood: school failure, underachievement, and learning difficulties

Differential Diagnosis

• Cerebral palsy (a motor handicap)
• Deafness
• Emotional deprivation
• Childhood autism

Management of Mental Retardation

• Treatable conditions: specific therapy to prevent further impairment
  • Congenital hypothyroidism: lifelong thyroid hormone
  • Galactosemia: eliminate galactose from diet
  • Phenylketonuria: eliminate phenylalanine from diet
• Intreatable conditions: supportive management
  • Treat associated problems (epilepsy, hearing defects)
  • Education & training based on the degree of mental retardation
  • Emotional & family support
  • Counseling for parents
  • Institutionalization for profoundly retarded children

Down Syndrome

• Genetic condition (Trisomy 21)
• Causes delays in physical and intellectual development
• Individuals with Down syndrome have 47 chromosomes instead of the typical 46

Clinical Features of Down Syndrome

• Round, flat face
• Almond-shaped eyes
• Slanting eyes with epicanthal folds
• Protruding tongue
• High-arched palate
• Malocclusion of teeth
• Small oral cavity
• Rough, dry skin
• Poor muscle tone
• Hyperflexibility of joints
• Short, broad hands with a single palmar crease (Simian crease)
• Clinodactyly (curvature of a finger)
• Broad feet with short toes, wide gap between the big and second toes
• Flat bridge of the nose
• Short, low-set ears
• Short neck and small head
• Brushfield spots (small white spots in the iris of the eye)

Associated Abnormalities of DS

• Congenital heart disease
• Gastrointestinal malformations (duodenal atresia, Hirschsprung disease)
• Ophthalmic problems (cataracts, nystagmus)
• Hearing defects
• Retarded linear growth with slow developmental progress
• Malignancies (leukemia)

Diagnostic Evaluation

• History and physical examination
• Chromosomal study and radiographic examination
• Antenatal examination (amniocentesis) for chromosomal abnormalities and alpha-fetoprotein estimation. Ultrasound (USG)

Treatment of Down Syndrome

• No specific management exists
• Treat associated conditions (infections, nutritional deficiencies, congenital malformations)
• Daily supportive care to prevent acquired health hazards
• Training in self-care or daily routine care based on the IQ level
• Early intervention and educational therapy
• Physical, speech, and occupational therapies
• Emotional and behavioral therapy
• Parent counseling

Mucopolysaccharidosis (MPS)

• Genetic disorders affecting the metabolism of glycosaminoglycans, leading to their accumulation in tissues.
• Clinical characteristics can vary among MPS types but typically involve Coarse facial features, skeletal deformities, short stature, and cognitive impairment
• Treatment options vary depending on the specific MPS type and range from enzyme replacement therapy (ERT) to hematopoietic stem cell transplantation (HSCT)

Phenylketonuria (PKU)

• Autosomal recessive metabolic disorder characterized by a deficiency in the enzyme phenylalanine hydroxylase.
• Accumulation of phenylalanine leads to neurological damage.
• Symptoms include mental retardation, hypopigmentation (lighter skin and hair), mousy odor, seizures, and eczema Elevated phenyl ketones in urine
• Diet restriction of phenylalanine is crucial in management

Autism

• Neurodevelopmental disorder characterized by difficulties in social communication and interaction, and restricted, repetitive patterns of behavior, interests, or activities.
• Symptoms typically appear during early childhood.
• Core symptoms:
  • Impaired social interaction (eye contact, response to others)
  • Impaired communication (language development)
  • Restricted repetitive behavior (preoccupation with hands, repetitive behaviors)
• Diagnostic criteria involve core symptoms, persistence of symptoms, onset before 3 years of age, and significant impairment in social, occupational or other areas

Prevalence & Etiology of Autism

• Male to female ratio is 4:1
• Prevalence is about 1 in 160 children
• Etiology is complex, with strong genetic basis, and environmental factors (maternal nutrition, infections such as rubella, alcohol, environmental exposure) may contribute to risk

Diagnostic Assessment

• Autism diagnostic interview revised (ADIR)
• Autism diagnostic observation schedule (ADOS)
• Screening with M-charts
• Child autism rating scale (CARS)

Prognosis of Autism

• No known cure but some may recover depending on early intervention
• Treatment goals include: lessen deficits and family stress, improved quality of life and functional independence, individualized and early interventions, family involvement, behavioral therapy and educational systems.

Prevention of Autism

• Early diagnosis and intervention may improve behaviors, language, and cognitive skills.
• Avoid exposure to toxins, alcohol, and tobacco during pregnancy, may reduce risk.

Treatment of Autism

• Early Start Denver Model (ESDM)
• Occupational, behavioral, communication, or speech therapy
• Relationship development intervention
• Structured teaching (TEACCH method or SCERTS model) for visual processing, fine motor skills, self-regulation, self-care skills (handwriting)
• Cognitive behavioral therapy
• Medications (antipsychotics)

Attention-Deficit/Hyperactivity Disorder (ADHD)

• Neurodevelopmental disorder affecting attention, impulsivity, and hyperactivity
• Generally diagnosed in children, progresses into adulthood
• Difficulty focusing on a single task
• About 1 in 10 children aged 5-17 years are diagnosed.
• Boys are more likely to be diagnosed than girls.
• Girls may exhibit primarily inattentive behaviors such as daydreaming, rather than hyperactivity.

Causes of ADHD

• Brain damage
• Exposure to environmental toxins (lead) during pregnancy
• Overuse of alcohol and tobacco during pregnancy
• Low birth weight
• Premature birth
• Low level of dopamine in the brain

Brain Differences in ADHD

• Structural differences in the brain, minimal grey matter volume in brain areas responsible for speech, self-control, decision making and muscle control.

How ADHD Affects The Brain

• Prefrontal cortex: organization, cognitive flexibility, self-control, and attention maintenance are affected.
• Reticular activating system: arousal and consciousness are affected
• Basal ganglia: motor control and movement inhibition are affected
• Limbic system: emotional regulation can be affected

Possible Signs of ADHD

• Lots of energy
• Difficulty following directions
• Difficulty waiting
• Disorganized
• Frequent fidgeting
• Can't sit still
• Interrupts
• Excessive talking
• Easily distracted
• Loses things frequently

Types of ADHD

• Predominantly inattentive type: problems with concentration and following instructions.
• Predominantly hyperactive-impulsive type: excessive fidgeting, restlessness, impulsive behaviors such as interrupting or not waiting for their turn.
• Combined type: showing symptoms of both inattentive and hyperactive-impulsive types

Diagnosis of ADHD

• Assessment of symptoms over the past six months
• Information gathering from teachers and family members
• Using rating scales to review symptoms
• Complete physical examination to rule out other conditions
• DSM-5-TR guidelines: symptoms must occur in two or more settings, impair daily activities, and start before age 12

Prevention of ADHD

• Avoiding environmental toxins (lead, alcohol, tobacco, drugs) during pregnancy.

Prognosis of ADHD

• With behavioral therapy and/or medication, children may live healthy lives.
• Without treatment, poorer outcomes and lifelong complications are probable

Is ADHD a Disability?

• Yes, the Americans with Disabilities Act (ADA) views ADHD as a developmental disability that can impact performance of tasks and daily living making education or school accommodations necessary.
• Learning difficulties such as dyslexia and dyscalculia are also disabilities requiring special education requirements and services.

Advantages of ADHD

• Hyperfocus, nonlinear thinking and problem-solving, resiliency, creativity, conversational skills, spontaneity, and ample energy

Health behaviors for ADHD

• Healthy eating habits (fruits, vegetables, lean protein, whole grains)
• Regular physical activity
• Limit screen time
• Sufficient sleep

Test your knowledge on key concepts in psychology related to intelligence, mental retardation, and ADHD. This quiz explores diagnostic criteria, symptoms, and treatment options for various conditions. Challenge yourself to see how well you understand these important topics in mental health.