Neurodevelopmental Disorders

Neurodevelopmental Disorders

Overview

  • Neurodevelopmental disorders are a new combination of disorders in the DSM-5.
  • Understanding what is considered normal vs. abnormal behavior is crucial.
  • Psychopathology refers to the study of mental disorders.
  • Early skill impairments can have a significant developmental impact.
  • Developmental disorders are typically first diagnosed in infancy, childhood, or adolescence.
  • Examples include:
    • Attention Deficit Hyperactivity Disorder (ADHD)
    • Specific Learning Disorders
    • Autism Spectrum Disorder
    • Intellectual Disability

Attention Deficit/Hyperactivity Disorder (ADHD)

  • Central features:
    • Inattention
    • Hyperactivity
    • Impulsivity
  • DSM-5 differentiates two categories of symptoms:
    • Problems of inattention
    • Problems of hyperactivity and impulsivity
  • Impairments:
    • Behavioral
    • Cognitive
    • Social
    • Academic

Diagnostic Criteria (DSM-5)

A. A persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development, as characterized by (1) and/or (2):

  1. Inattention: Six (or more) of the following symptoms have persisted for at least 6 months to a degree that is inconsistent with developmental level and that negatively impacts directly on social and academic/occupational activities. For older adolescents and adults (age 17 and older), at least five symptoms are required.

    • a. Often fails to give close attention to details or makes careless mistakes in schoolwork, at work, or during other activities (e.g., overlooks or misses details, work is inaccurate).
    • b. Often has difficulty sustaining attention in tasks or play activities (e.g., has difficulty remaining focused during lectures, conversations, or lengthy reading).
    • c. Often does not seem to listen when spoken to directly (e.g., mind seems elsewhere, even in the absence of any obvious distraction).
    • d. Often does not follow through on instructions and fails to finish schoolwork, chores, or duties in the workplace (e.g., starts tasks but quickly loses focus and is easily sidetracked).
    • e. Often has difficulty organizing tasks and activities (e.g., difficulty managing sequential tasks; difficulty keeping materials and belongings in order; messy, disorganized, work; has poor time management; fails to meet deadlines).
    • f. Often avoids, dislikes, or is reluctant to engage in tasks that require sustained mental effort (e.g., schoolwork or homework; for older adolescents and adults, preparing reports, completing forms, reviewing lengthy papers).
    • g. Often loses things necessary for tasks or activities (e.g., school materials, pencils, books, tools, wallets, keys, paperwork, eyeglasses, or mobile telephones).
    • h. Is often easily distracted by extraneous stimuli (for older adolescents and adults, may include unrelated thoughts).
    • i. Is often forgetful in daily activities (e.g., chores, running errands; for older adolescents and adults, returning calls, paying bills, keeping appointments).

  2. Hyperactivity and Impulsivity: Six (or more) of the following symptoms have persisted for at least 6 months to a degree that is inconsistent with developmental level and that negatively impacts directly on social and academic/occupational activities. For older adolescents and adults (age 17 and older), at least five symptoms are required.

    • a. Often fidgets with or taps hands or feet or squirms in seat.
    • b. Often leaves seat in situations when remaining seated is expected (e.g., leaves his or her place in the classroom, in the office or other workplace, or in other situations that require remaining in place).
    • c. Often runs about or climbs in situations where it is inappropriate. (Note: In adolescents or adults, may be limited to feeling restless.)
    • d. Often unable to play or engage in leisure activities quietly.
    • e. Is often "on the go," acting as if "driven by a motor" (e.g., is unable to be or uncomfortable being still for an extended time, as in restaurants, meetings; may be experienced by others as being restless or difficult to keep up with).
    • f. Often talks excessively.
    • g. Often blurts out an answer before a question has been completed (e.g., completes people's sentences; cannot wait for turn in conversation).
    • h. Often has difficulty waiting his or her turn (e.g., while waiting in line).
    • i. Often interrupts or intrudes on others (e.g., butts into conversations, games, or activities; may start using other people's things without asking or receiving permission; for adolescents or adults, may intrude into or take over what others are doing).

B. Several inattentive or hyperactive-impulsive symptoms were present prior to age 12 years.

C. Several inattentive or hyperactive-impulsive symptoms are present in two or more settings (e.g., at home, school or work; with friends or relatives; in other activities).

D. There is clear evidence that the symptoms interfere with, or reduce the quality of, social, academic, or occupational functioning.

E. The symptoms do not occur exclusively during the course of schizophrenia or another psychotic disorder and are not better explained by another mental disorder (e.g., mood disorder, anxiety disorder, dissociative disorder, personality disorder, substance intoxication or withdrawal).

  • Specify whether:
    • Combined presentation: If both Criterion A1 (inattention) and Criterion A2 (hyperactivity-impulsivity) are met for the past 6 months.
    • Predominantly inattentive presentation: If Criterion A1 (inattention) is met but Criterion A2 (hyperactivity-impulsivity) is not met for the past 6 months.
    • Predominantly hyperactive/impulsive presentation: If Criterion A2 (hyperactivity-impulsivity) is met and Criterion A1 (inattention) is not met for the past 6 months.

ADHD: Statistics

  • Prevalence:
    • 3% to 9% worldwide
    • 11% of children in the U.S. aged 4 to 17
  • Onset: 3 or 4 years
  • Boys : Girls = 3:1
  • Possible cultural construct
  • Adults with ADHD:
    • Lower-level jobs
    • 2.5 fewer years of education
    • More likely to be divorced, have substance use problems, and antisocial personality disorder
    • High-risk behaviors
  • High comorbidity:
    • Oppositional Defiant Disorder (ODD)
    • Mood disorders

ADHD: Causes

  • Genetics:
    • Familial component
    • Copy number variants—CNVs
    • Dopamine:
      • DRD4, DAT1, DRD5 genes and Ritalin
    • Norepinephrine
    • GABA
    • Serotonin
  • Neurobiological contributions:
    • Smaller brain volume (3-4%)
    • The role of toxins
      • Allergens and food additives (no evidence)
    • Maternal smoking:
      • Increases risk
      • Interacts with genetic predisposition
  • Psychosocial and social factors:
    • Negative responses from:
      • Teachers
      • Peers
      • Adults
    • Peer rejection
    • Low self-esteem
    • Poor self-image

Treatment of ADHD

  • Treatment on two fronts:
    • Psychosocial intervention:
      • Improving academic performance, decreasing disruptive behavior, and improving social skills
      • Behavioral interventions before medication
      • Parent training
      • Social skills training
    • Biological intervention:
      • Goals:
        • Reduce impulsivity and hyperactivity
        • Improve attention
      • Stimulants (e.g., Ritalin)
      • Other Medications: Adderall, Strattera, Tenex, Clonidine
      • Effects of medications:
        • Improve compliance
        • Decrease negative behaviors
        • Do not affect learning and academic performance
        • Possible abuse issues
        • Side effects
      • Psychopharmacogenetics: The study of how your genetic makeup influences your response to certain drugs.
  • Combined treatments:
    • Behavioral and medication
    • Recommended
    • Superior to individual treatments? Controversy exists

Specific Learning Disorders

  • Specific learning disorder: Performance substantially below expected levels based on:
    • Age
    • IQ
    • Education
  • Actual vs. expected achievement (