Neurodevelopmental disorders

Criterion A – Social Communication & Interaction Deficits

Persistent deficits in social communication and social interaction across contexts, shown by all of the following (currently or by history):

1. Social-emotional reciprocity:

   • Abnormal social approach

   • Poor back-and-forth conversation

   • Reduced sharing of interests, emotions, or affect

   • Failure to start or respond to social interactions

2. Nonverbal communication:

   • Poor integration of verbal and nonverbal cues

   • Abnormal eye contact or body language

   • Difficulty understanding or using gestures

   • Little or no facial expressions or other nonverbal communication

3. Relationships:

   • Trouble adjusting behavior to different social contexts

   • Difficulty sharing imaginative play or making friends

   • Little or no interest in peers

Criterion B – Restricted & Repetitive Behaviors

Restricted, repetitive patterns of behavior, interests, or activities, with at least two of the following (currently or by history):

1. Repetitive movements/speech/use of objects:

   • Stereotyped motor movements

   • Lining up or flipping objects

   • Echolalia or idiosyncratic phrases

2. Insistence on sameness/routines:

   • Extreme distress at small changes

   • Difficulty with transitions

   • Rigid thinking, greeting rituals

   • Need to take same route or eat same food daily

3. Highly restricted, fixated interests:

   • Abnormally intense or focused interests

   • Strong attachment to unusual objects

   • Excessively narrow, perseverative interests

4. Sensory hyper- or hyporeactivity / unusual sensory interest:

   • Indifference to pain or temperature

   • Adverse responses to sounds or textures

   • Excessive smelling/touching objects

   • Visual fascination with lights or movement

Severity Specifier – Level 3 (Requiring very substantial support)

• Social communication:

  • Severe deficits in verbal and nonverbal skills

  • Very limited initiation of social interaction

  • Minimal response to social approaches

  • Example: few understandable words; rarely initiates; approaches others only to meet basic needs in unusual ways

• Restricted/repetitive behaviors:

  • Extreme inflexibility and difficulty with change

  • RRBs interfere with functioning in all areas

  • Very high distress/difficulty changing focus or action

Severity Specifier – Level 2 (Requiring substantial support)

• Social communication:

  • Marked deficits even with support

  • Limited initiation of social interaction

  • Reduced or abnormal responses to social overtures

  • Example: simple sentences; interaction limited to narrow interests; noticeably odd nonverbal communication

• Restricted/repetitive behaviors:

  • Clear inflexibility and difficulty with change

  • RRBs obvious to casual observer

  • Interfere with functioning in multiple contexts

  • Distress/difficulty changing focus or action

Severity Specifier – Level 1 (Requiring support)

• Social communication (without support):

  • Noticeable impairments

  • Difficulty initiating social interactions

  • Atypical or unsuccessful responses to social overtures

  • May seem less interested in social interaction

  • Example: speaks in full sentences, but conversations break down; odd, usually unsuccessful attempts to make friends

• Restricted/repetitive behaviors:

  • Inflexibility interferes with functioning in one or more contexts

  • Difficulty switching between activities

  • Organizational/planning problems limit independence

Criterion A – ADHD: Core Requirement

Persistent pattern of inattention and/or hyperactivity-impulsivity that:

• Lasts ≥ 6 months

• Is inconsistent with developmental level

• Directly impairs social and academic/occupational functioning

• Not better explained by oppositionality, defiance, hostility, or not understanding tasks

Criterion A1 – Inattention: Symptom Threshold

• Children/adolescents (<17): ≥ 6 inattention symptoms

• Older adolescents/adults (≥17): ≥ 5 inattention symptoms

• Present for ≥ 6 months

• Inconsistent with developmental level

• Directly impairs social and academic/occupational functioning

Criterion A1 – Inattention: Symptom List (a–i)

Often:
a. Fails to pay close attention; makes careless mistakes (school, work, other tasks)
b. Has difficulty sustaining attention (tasks, play, lectures, conversations, reading)
c. Does not seem to listen when spoken to directly (mind seems elsewhere)
d. Starts tasks but does not follow through; loses focus; easily sidetracked
e. Has difficulty organizing tasks/activities (messy, poor time management, missed deadlines)
f. Avoids/dislikes tasks needing sustained mental effort (schoolwork, reports, forms)
g. Loses items needed for tasks (books, tools, keys, paperwork, glasses, phone, etc.)
h. Is easily distracted by external stimuli (or unrelated thoughts in older individuals)
i. Is forgetful in daily activities (chores, errands, calls, bills, appointments)

Criterion A2 – Hyperactivity/Impulsivity: Symptom Threshold

• Children/adolescents (<17): ≥ 6 hyperactivity/impulsivity symptoms

• Older adolescents/adults (≥17): ≥ 5 symptoms

• Present for ≥ 6 months

• Inconsistent with developmental level

• Directly impairs social and academic/occupational functioning

• Not just oppositionality, defiance, hostility, or misunderstanding instructions

Criterion A2 – Hyperactivity/Impulsivity: Symptom List (a–i)

Often:
a. Fidgets, taps hands/feet, or squirms in seat
b. Leaves seat when staying seated is expected (class, office, etc.)
c. Runs about or climbs in inappropriate situations (or feels very restless in teens/adults)
d. Cannot play or engage in leisure activities quietly
e. Is “on the go,” acts as if “driven by a motor”; hard for others to keep up
f. Talks excessively
g. Blurts out answers; completes others’ sentences; cannot wait in conversation
h. Has difficulty waiting turn (e.g., in lines)
i. Interrupts or intrudes on others (butts into conversations/games; uses others’ things; takes over activities)

HiTOP – ADHD as Disinhibited Externalizing

• HiTOP: dimensional model grouping disorders by underlying traits.

• ADHD (especially hyperactive–impulsive type) loads on the Disinhibited Externalizing spectrum.

• Core traits: impulsivity, poor inhibitory control, rule-breaking/novelty seeking, disorganization.

• Shares this spectrum with ODD, conduct disorder, substance use disorders.

• ADHD is seen as an extreme of disinhibited/externalizing traits, not an isolated category.