An international research team built an atlas of the basal ganglia using studies of human, macaque, marmoset and mouse brains, profiling 25.5 million cells to help scientists study brain function and disease.
The findings were released November 12, 2026, in a collection of 26 papers involving hundreds of researchers at more than 50 institutions. The 25.5 million profiled cells include 21 million from humans, 3 million from macaques and 1.5 million from marmosets. The wider atlas also includes mouse research.
The basal ganglia are groups of brain structures connected to each other that are involved in movement, forming habits, making decisions and emotion. They have been linked to conditions including Parkinson’s disease, Huntington’s disease and schizophrenia. To make results comparable across research groups, the teams combined ways of classifying cells with information about their biology and locations in the brain.
This information included gene activity, how DNA is regulated and where cells are located in brain tissue. The shared framework is intended to help researchers identify which cell types and biological processes need more study across species. One reported finding was a previously unknown type of spiny projection neuron associated with genetic risk for schizophrenia.
The atlas is a research resource, not a treatment or proof of what causes any particular disorder. Its value will depend on how scientists use it in further studies. Researchers hope the cross-species reference will support future work on the basal ganglia.
They also hope it will contribute to efforts to map more of the brain.