Neurodevelopmental disorders are conditions that emerge early in life and affect brain development, shaping attention, behavior, learning, and social functioning. AP Psychology emphasizes ADHD and ASD, including core characteristics and major contributing factors.

Core Idea: Neurodevelopmental Disorders

Neurodevelopmental disorders begin during development and are marked by age-inappropriate behavior that interferes with academic, social, or everyday functioning. Typical onset is in childhood, though challenges may persist into adolescence and adulthood.

Key framing points for AP Psychology:

• Symptoms reflect differences in brain development and self-regulation

• Impairment must be evaluated relative to developmental expectations

• Causes are best understood as multifactorial: environmental, physiological, and genetic influences can interact

Attention-Deficit/Hyperactivity Disorder (ADHD)

ADHD involves a persistent pattern of inattention and/or hyperactivity-impulsivity that is inconsistent with developmental level and negatively affects functioning across settings (e.g., school and home).

Symptom Domains

Inattention commonly includes:

• Difficulty sustaining attention and following through on tasks

• Disorganisation; losing materials; forgetfulness

• Appearing not to listen; being easily distracted

Hyperactivity-impulsivity commonly includes:

• Fidgeting; difficulty remaining seated when expected

• Excessive talking; interrupting or intruding on others

• Difficulty waiting turn; acting without considering consequences

Developmental and Context Clues

AP-level interpretation stresses “age-inappropriate” and cross-situational impairment:

• Younger children: more visible motor activity and classroom disruption

• Adolescents/adults: more restlessness, poor time management, and sustained attention difficulties

• Symptoms should be present in more than one setting to support an ADHD interpretation (not just one class or one teacher)

Contributing Factors (Environmental, Physiological, Genetic)

ADHD is not explained by a single cause.

Diagram of major basal ganglia circuit pathways, with arrows and symbols indicating excitatory, inhibitory, and dopaminergic influences. This helps visualize the “striatal” side of frontostriatal circuitry often discussed in ADHD when introducing executive control, action selection, and regulation of behavior. Source

Commonly cited contributors include:

• Genetic influences: ADHD tends to run in families; heritable liability helps explain persistence across development

• Physiological influences: differences in executive functioning and attention regulation; involvement of frontal-striatal networks is often discussed in introductory psychology

• Environmental influences: prenatal/perinatal risks (e.g., exposure to toxins), early adversity, and chronic stress can increase risk or worsen symptom expression

Autism Spectrum Disorder (ASD)

ASD is defined by difficulties in social communication and social interaction alongside restricted, repetitive patterns of behavior or interests, with symptoms emerging early in development and varying in severity (“spectrum”).

A key AP focus is that challenges reflect developmental differences rather than deliberate noncompliance, and behaviors should be interpreted relative to developmental level and context.

Core Characteristics

Social communication/interaction differences may include:

• Difficulty with reciprocal conversation and social-emotional exchange

• Reduced use or understanding of nonverbal cues (e.g., eye contact, gestures)

• Challenges developing and maintaining peer relationships appropriate to developmental level

Restricted/repetitive behaviors or interests may include:

• Repetitive movements or speech; insistence on sameness and routines

• Highly focused interests that are intense or unusual in focus

• Sensory differences (over- or under-reactivity to sound, textures, lights)

Developmental Patterns and “Spectrum” Emphasis

ASD can look different across individuals and ages:

• Early childhood: delayed or atypical social attention, limited shared enjoyment, strong routine dependence

• School years: social misunderstandings, difficulty with pragmatic language, rigid thinking

• Adolescence/adulthood: social fatigue, need for predictability, variable independence depending on supports and co-occurring needs

Contributing Factors (Environmental, Physiological, Genetic)

ASD is also multifactorial:

• Genetic influences: strong evidence for inherited contributions and complex genetic architecture

• Physiological influences: atypical patterns of brain development and connectivity are commonly referenced at an introductory level

• Environmental influences: certain prenatal/perinatal factors may elevate likelihood; these influences are best viewed as shaping risk rather than acting as sole causes

Distinguishing ADHD and ASD (AP-Relevant Comparisons)

While comorbidity can occur, the core impairment patterns differ:

• ADHD: primary difficulties with attention regulation, impulse control, and activity level

• ASD: primary difficulties with social communication plus restricted/repetitive behaviors and/or sensory differences

• Overlap can appear as distractibility, social friction, or emotional dysregulation, but the reasons behind behaviors (impulsivity vs. social-pragmatic differences/rigidity) guide interpretation