Short answer: NO
Explanation: The triune brain or three-brain theory was an evolutionary model proposed by the physician Paul D. MacLean in the mid 1960’s. This model was acclaimed as the first sustainable theory that explained from an evolutional perspective the development of the human mind. However, as every scientific postulate, it was always subject to refutation as the coming of new knowledge and explanations of the evolution and architecture of the human brain.
Three major current discoveries are incompatible with the triune brain, positioning it as a superseded theory:
1. First, the fact that it is based on the idea of the human linear evolution, idea which was abandoned by evolutionary biologists since the early 1980’s in favor of the ramified model of evolution. Under the old model, it sounded quite logical that the human brain ontogenetic structure was the replication of its phylogenetic origin. However, now we know that the Homo sapiens were not the result of such linear development, but of a much more complex system.
2. Second, the decoding of the human genome on the early 2000’s gave us a molecular-based framework for demonstrating the linkage between species as we never could before. Under this new approach, we discovered that the genetic of the human brain share much more with the mice, and that the basal ganglia, named under the triune model as the “reptilian complex”, is genetically bounded to modern vertebrates rather than reptiles genes.
3. Finally, the cytoarchitecture of the “human neocortex” as named by the triune model is present in several non-mammals. Whether not presented in the same structure as in the human brain, pallial areas are identified in birds, and are responsible of the same functions of the human neocortex such as learning and probem-solving.
In summary, the triune brain was popular and scientifically accurate at the moment it was published (50 years ago), but as science has advanced, the knowledge that supported its conception has been outdated by more new and accurate advancements in the understanding of human brain.