oasis

Open Access Series of Imaging Studies (OASIS)

Introduction

The Open Access Series of Imaging Studies (OASIS) is a project that provides neuroimaging data to the scientific community, making brain MRI datasets freely available for research on [Alzheimer's Disease](/diseases/alzheimers-disease) and brain aging. [@marcus2007] OASIS has become one of the most widely used neuroimaging datasets, with over 10,000 MRI scans from more than 1,500 subjects.

Datasets

OASIS-1 (Cross-sectional)

Open Access Series of Imaging Studies (OASIS)

Introduction

The Open Access Series of Imaging Studies (OASIS) is a project that provides neuroimaging data to the scientific community, making brain MRI datasets freely available for research on [Alzheimer's Disease](/diseases/alzheimers-disease) and brain aging. [@marcus2007] OASIS has become one of the most widely used neuroimaging datasets, with over 10,000 MRI scans from more than 1,500 subjects.

Datasets

OASIS-1 (Cross-sectional)

The initial OASIS dataset contains cross-sectional MRI data from 416 subjects aged 18 to 96 years, including both cognitively normal individuals and patients with [Alzheimer's Disease](/diseases/alzheimers-disease).[@marcus2007]

OASIS-2 (Longitudinal)

OASIS-2 contains longitudinal MRI data from 150 cognitively normal adults and 100 patients with Alzheimer's Disease, scanned at multiple time points over 2-3 years. [@marcus2010]

OASIS-3 (Longitudinal)

OASIS-3 is the most recent iteration, containing longitudinal data from over 600 subjects, including normal controls, individuals with mild cognitive impairment, and Alzheimer's patients, with up to 15 years of follow-up.

Key Features

Large Sample Size

OASIS provides neuroimaging data from hundreds of subjects, enabling robust statistical analyses of aging and disease effects. [@marcus2010]

Extensive Phenotyping

Each subject undergoes comprehensive clinical and neuropsychological assessments, including:

• Cognitive Testing: MMSE, CDR, and neuropsychological batteries
• Dementia Staging: Clinical Dementia Rating scale
• Demographic Information: Age, sex, education, and APOE genotype

Quality-controlled Data

All MRI data undergo rigorous quality control and preprocessing, including:

• Skull stripping and tissue segmentation
• Registration to standard space
• Automated labeling of brain structures

Data Collection

MRI Protocols

• T1-weighted MPRAGE: High-resolution anatomical images (1mm isotropic)
• Multiple Echoes: For improved segmentation
• Longitudinal Sessions: Multiple time points for each subject

Clinical Assessments

• Cognitive Measures: MMSE, logical memory, digit span
• Dementia Rating: CDR scores for staging
• APOE Genotyping: Genetic risk factor data

Major Findings

Brain Aging Patterns

OASIS data have demonstrated that normal aging is associated with progressive brain volume loss, with region-specific patterns[@koenig2011]

Alzheimer's Disease Signatures

The dataset has enabled identification of characteristic patterns of hippocampal atrophy and cortical thinning in AD[@buckner2005]

Cognitive Reserve

Studies using OASIS have shown that higher education and cognitive engagement provide resilience against brain pathology[@samieri2013]

Subjective Cognitive Impairment

OASIS has contributed to understanding the relationship between subjective cognitive complaints and objective brain changes[@pedersen2013]

Research Applications

OASIS has been used for numerous research applications:

Impact on the Field

OASIS has had significant impact by:[@marcus2010]

• Democratizing access to high-quality neuroimaging data
• Enabling methodological research on image analysis
• Supporting biomarker development and validation
• Facilitating machine learning applications in neuroimaging

Data Access

OASIS data are freely available to researchers:[@marcus2007]

• OASIS-1: https://www.oasis-brains.org/
• OASIS-2: https://www.oasis-brains.org/
• OASIS-3: https://www.oasis-brains.org/

Future Directions

OASIS continues to expand with:[@marcus2010]

• OASIS-4 with more diverse populations
• Integration with other clinical datasets
• Advanced multi-modal imaging
• Machine learning-ready datasets

See Also

• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [ADNI](/projects/adni)
• [MRI Biomarkers](/biomarkers/mri-atrophy-cbs-psp)
• [Mild Cognitive Impairment](/diseases/mild-cognitive-impairment)

External Links

• [OASIS Official Website](https://www.oasis-brains.org/)
• [OASIS Data Download](https://www.oasis-brains.org/#data)
• [OASIS Publications](https://www.oasis-brains.org/#publications)

Pathway Diagram

The following diagram shows the key molecular relationships involving oasis discovered through SciDEX knowledge graph analysis: