Neurodevelopmental Disorders

Neurodevelopmental Disorders Overview

  • Covers various disorders including:

    • Intellectual Disabilities

    • Autism Spectrum Disorders

    • Elimination Disorders

    • Tic Disorders (Tourette’s Disorder)

    • Learning Disorders

    • Attention-Deficit Hyperactivity Disorder (ADHD)

    • Oppositional Defiant Disorder (ODD)

    • Conduct Disorder (CD)

Intellectual Disability

  • Defined as significantly below average intellectual functioning with an IQ of 70 or below.

  • Diagnosed when adapting to normal life demands is seriously impaired.

Main Features

  • Two Main Problems:

    • Fundamental deficit in cognitive abilities:

      • Abstract judgment

      • Planning

      • Problem solving

    • Impaired adaptive functioning in:

      • Conceptual skills (schooling)

      • Social skills (communication)

      • Practical skills (regulating behavior)

  • Most individuals will require special assistance to cope with daily challenges.

Prevalence

  • Mild Intellectual Disability:

    • 85% of ID Population

    • Able to learn skills up to the 3rd-6th grade level

    • May live independently with jobs.

  • Moderate Intellectual Disability:

    • 10% of ID Population

    • Can learn basic reading and writing; requires supervision.

  • Severe Intellectual Disability:

    • 5% of ID Population

    • Limited ability to read/write but may develop self-help skills with supervision.

  • Profound Intellectual Disability:

    • 1% of ID Population

    • Requires intensive support, may communicate non-verbally.

Onset and Behavioral Issues

  • Onset typically occurs in infancy with observable behavioral problems arising in childhood:

    • Aggression, dependency, impulsivity, stubbornness.

    • Gullibility increases vulnerability to exploitation.

  • Physical signs may include:

    • Short stature

    • Seizures

    • Malformations in eyes, ears, and face.

Causes of Intellectual Disability

  • Genetic Factors: 5% of cases.

  • Environmental Factors:

    • Toxins exposure: 25%

    • 30% have no identifiable cause.

Inherited Forms of Intellectual Disability

Phenylketonuria (PKU)

  • Enzyme deficiency leading to phenylalanine build-up.

  • 100% preventable with diet; screened at birth.

Tay-Sachs Disease

  • Metabolic disorder from absent hexosaminidase A enzyme.

  • Progressive loss of abilities, leads to death by age 5.

  • Most prevalent in individuals of Jewish descent.

Fragile X Syndrome

  • Linked to the fragile X gene on the X chromosome.

  • Most common in males; associated with mild to moderate ID and ADHD.

Down Syndrome

  • Caused by an extra 21st chromosome.

  • Exhibits characteristic facial features and typically requires institutional care early in life.

Environmental Causes of Intellectual Disability

  • Prenatal diseases (e.g., Rubella).

  • Difficult deliveries and premature births.

  • Substance abuse during prenatal periods.

  • Toxic exposure (e.g., lead).

Fetal Alcohol Syndrome (FAS)

  • 100% preventable; leading cause of intellectual disabilities.

  • Linked to maternal alcohol consumption.

  • Characteristic facial abnormalities and balance problems.

Interventions for Intellectual Disability

  • Currently no cure; some forms are preventable.

  • Behavioral interventions involving family can be effective.

Autism Spectrum Disorder (ASD)

  • A heterogeneous neurodevelopmental disorder exhibiting a wide range of symptoms.

  • Prevalence rates vary (e.g., 1 in 54 as of 2020).

Symptoms of Autism

  • Communication Deficits:

    • Limited use of speech

    • Lack of non-verbal communication cues.

  • Social Deficits:

    • Developmental lag in social interactions beginning around 6 months of age.

    • Lack of eye contact and reciprocal smiles.

  • Motor Behavior Deficits:

    • Presence of compulsive or ritualistic actions (stereotypies).

Classification of Autism Severity

  • High Functioning Autism (formerly Asperger’s Syndrome):

    • Good cognitive skills with significant social impairments.

  • Severe Autism

    • Profound disabilities requiring support.

Tic Disorders – Tourette’s Disorder

  • Characterized by motor tics (e.g., eye blinking) and verbal tics (e.g., grunting).

  • Treatment options include behavioral modification and medications.

Attention-Deficit Hyperactivity Disorder (ADHD)

  • Affects approximately 6% of children; more common in males.

  • Characterized by inattention, hyperactivity, and impulsivity.

Diagnostic Criteria for ADHD

  • Symptoms must persist for at least 6 months and show functional impairment.

  • Requires a minimum number of symptoms based on age of the individual:

    • 6 symptoms required for children under 17

    • 5 symptoms for adults.

Treatment Options for ADHD

  • Medication (e.g., stimulants like Ritalin).

  • Cognitive-Behavioral Therapy.

  • Early interventions yield the best outcomes.

Oppositional Defiant Disorder (ODD)

  • Characterized by hostility, stubbornness, and temper issues.

  • Early detection and treatment can prevent progression to conduct disorder.

Conduct Disorder (CD)

  • Often co-occurs with ODD.

  • Involves repeated violations of rights and social norms, leading to severe behavioral issues.