ABCD Study (Adolescent Brain Cognitive Development)

The Adolescent Brain Cognitive Development (ABCD) Study is the largest long-term study of brain development and child health in the United States. It is a multisite longitudinal cohort study following ~11,800 children from ages 9-10 through adolescence, with repeated neuroimaging, cognitive testing, biospecimen collection, and behavioural assessments.

Study Design

• Sponsor: NIH (NIDA, NIAAA, NIMH, NCI, and others)
• Coordinating Center (CC): UC San Diego (Sandra Brown, Ph.D.)
• Data Analysis, Informatics & Resource Center (DAIRC): Provides data curation, analysis tools, and open access
• Sites: 21 research sites across the United States
• Cohort: ~11,800 children enrolled at ages 9-10, followed for 10+ years
• Data release: Curated, anonymised data released annually since 2018 via the NIMH Data Archive (NDA); current release is ABCD 7.0

Assessment Domains

The ABCD protocol is organised into standardised, harmonised domains assessed at varying intervals:

Neurocognition

• Attention and memory — including delayed-match-to-sample (DMTS) and delayed-response-tasks-working-memory paradigms
• Executive function — including intradimensional-extradimensional-shift (ID/ED) set-shifting, one-touch-stockings-cambridge (OTS) spatial planning
• Neurocognition — NIH Toolbox Cognitive Battery (flanker, list sorting, picture sequence, pattern comparison, oral reading, dimensional change card sort)
• Assessed annually

Brain Imaging

• sMRI — 3D T1-weighted MPRAGE for cortical/subcortical segmentation
• DTI/dMRI — HARDI with multiple b-values for white matter tract segmentation
• fMRI — resting state and task-based (high spatial and temporal resolution)
• T2-weighted — variable flip angle FSE for white matter lesions and CSF
• Harmonised across Siemens, GE, and Philips scanners
• Conducted every other year
• Protocol details: github.com/nih-fmrif/abcd_protocols

Mental Health

• Clinical interview (KSADS-5)
• Self-report measures of depression, anxiety, psychosis spectrum
• Family history of psychopathology
• Assessed annually

Substance Use

• Self-report and toxicology (urine, oral fluid)
• Alcohol, tobacco, cannabis, and other substances
• Peer and family substance use
• Assessed semi-annually

Physical Health and Biospecimens

• Blood (A1C, lipids), genetics, epigenetics
• Pubertal hormones (hair, urine)
• Sleep and nutrition
• Physical health measures
• Collected every other year

Social, Cultural, and Environmental

• Cultural values, discrimination experiences
• Family, friends, and community
• Community involvement
• Education context (linked school data)
• Environmental exposures and policy data
• Assessed annually

Technology and Passive Sensing

• Social media use
• Smartphone passive sensing
• Fitbit wearable data
• Novel technology assessments

Data Access

ABCD follows an open science model — curated, anonymised data is released annually to the research community worldwide.

• NDA: data-archive.nimh.nih.gov/abcd
• ABCD Documentation: docs.abcdstudy.org
• DEAP (Data Exploration and Analysis Portal): docs.deapscience.com
• NBDC Data Hub: nbdc-datahub.org
• Data is controlled-access; requires NIH-approved user account and institutional IT security compliance

Relevance

The ABCD Study is a major resource for:

• Normative brain development trajectories across adolescence
• Cognitive test batteries validated in large adolescent samples — directly relevant to delayed-match-to-sample, intradimensional-extradimensional-shift, and other tasks in this wiki
• Risk and resilience factors for psychopathology, substance use, and cognitive impairment
• Open data for secondary analysis — one of the largest neuroimaging + cognition datasets available

Related Pages

delayed-match-to-sample | delayed-response-tasks-working-memory | intradimensional-extradimensional-shift | one-touch-stockings-cambridge | cantab | nonverbal-cognitive-tasks