Chapter 13: Neurodevelopmental and Neurocognitive Disorders

Neurodevelopmental disorders emerge during childhood and continue affecting individuals throughout adulthood, disrupting the typical progression of cognitive, social, and behavioral development. Attention-deficit/hyperactivity disorder manifests through persistent difficulties with sustained focus, excessive motor activity, and impulsive decision-making, with evidence pointing to dopamine system irregularities and structural brain variations as underlying mechanisms, while treatment typically combines psychostimulant medications with behavioral supports and parental coaching. Specific learning disorders involve significant gaps between intellectual capability and academic performance in areas such as reading, mathematics, or written expression, stemming from neurobiological variations in language-processing and mathematical reasoning brain regions. Autism spectrum disorder presents with core deficits in social reciprocity and communication alongside restricted or repetitive behavioral patterns, involving genetic vulnerability and atypical development of social brain networks, though vaccines have no causal relationship. Intellectual disability encompasses both below-average cognitive functioning and adaptive behavior deficiencies, arising from genetic syndromes, prenatal factors, birth trauma, or environmental deprivation. Additional neurodevelopmental conditions affect communication fluency and motor control. In contrast, neurocognitive disorders typically emerge in later adulthood, characterized by acquired declines in memory, executive functioning, and reasoning. Delirium represents an acute confusional state with rapid onset and fluctuating severity, often resulting from medical complications or substance effects. Major and mild neurocognitive disorders involve progressive cognitive deterioration through various disease mechanisms, including Alzheimer's pathology with amyloid accumulation and tau tangles, vascular injury from cerebral infarcts, frontotemporal degeneration affecting personality and language, and neurodegenerative conditions like Parkinson's and Huntington's disease. Interventions span pharmacological approaches targeting neurotransmitter deficiency, behavioral and cognitive strategies, and comprehensive caregiver support systems designed to optimize functioning and quality of life across these conditions.