Understanding the human brain’s structure and function requires standardized mapping. Scientists need consistent methods to compare findings across different studies and individuals. Brain atlases provide a common framework to navigate and analyze the brain’s detailed anatomy.
Understanding the Brain’s Blueprint
The Desikan-Killiany atlas is a common parcellation scheme that divides the cerebral cortex, the brain’s outer layer, into distinct regions. This atlas provides a standardized map by segmenting the cortex into “gyral-based regions of interest,” meaning it uses the brain’s natural folds and grooves, known as gyri and sulci, as boundaries for these subdivisions. A gyrus is a ridge on the brain’s surface, bordered by sulci, which are the grooves or fissures. The atlas includes 68 distinct cortical regions, offering a detailed yet manageable framework for analysis.
This standardized map is important because individual brains exhibit natural variations in shape and size. Without a consistent way to define brain areas, comparing data from different people or studies would be difficult. The Desikan-Killiany atlas helps ensure that when researchers refer to a specific brain region, they are all talking about the same anatomical area, promoting consistency and reproducibility in brain studies.
How the Atlas Guides Neuroimaging
The Desikan-Killiany atlas is used in neuroimaging research, especially with Magnetic Resonance Imaging (MRI) scans. It works with specialized software, such as FreeSurfer, to automatically identify and measure specific brain regions. FreeSurfer uses the atlas to segment the brain, dividing MRI images into predefined cortical areas.
Once the brain is segmented, researchers can extract quantitative information about each region. For instance, they can measure the volume, thickness, or surface area of specific cortical areas. Researchers also track how these measurements change over time, which is valuable for studying brain development, aging, or the progression of neurological conditions. This automated analysis provides objective data about brain structure for large-scale studies.
Impact on Brain Research
The Desikan-Killiany atlas has influenced the field of neuroscience by providing a standardized method for analyzing brain structure. This standardization allows for direct comparisons of brain imaging data across different research studies and diverse populations. Before such atlases were widely adopted, comparing findings from various research groups was often challenging due to inconsistencies in how brain regions were defined.
The consistent framework offered by the atlas has accelerated the understanding of various aspects of brain health and disease. Researchers have utilized it to investigate typical brain development trajectories, observe changes associated with aging, and explore structural abnormalities linked to neurological conditions such as Alzheimer’s disease or psychiatric conditions like major depressive disorder. This common reference point facilitates collaborative research and the pooling of data, leading to more robust and generalizable findings in brain research.
The Atlas’s Ongoing Development
The field of neuroimaging is evolving, and brain atlases continue to be refined to enhance their accuracy and utility. The Desikan-Killiany atlas has a successor, the Desikan-Killiany-Tourville (DKT) atlas, which is an advancement in this mapping effort. The DKT atlas aimed to improve upon the original by revising some boundaries and removing regions with unclear definitions, leading to greater anatomical consistency across individuals. These revisions often involved conforming to clearer anatomical landmarks, such as the deep parts of the brain’s grooves. Both the original Desikan-Killiany and its DKT successor remain important tools in neuroimaging, adapted and refined as technology and understanding of the human brain continue to advance.