This criticism implied a need, on the one hand for objective methods of parcellation and on the other for strategies that capture anatomical variations between individual brains. Long before Talairach and Paxinos, Brodmann and others' work had been criticized for its reliance on subjective classifica tion criteria, poor reproducibility and an inability to account for inter-individual variation. However, as time moved on, new exigencies resulted in a series of further developments. These works, published in print format, met a fundamental need. In 1982, George Paxinos published his famous atlas of ‘The Rat Brain in Stereotaxic Coordinates', which provided an equivalent framework for the rat, later going on to publish similar atlases for the rhesus monkey and the mouse. In 1967, Jean Talairach and Pierre Tournoux published the first edition of their atlas of the human brain, which became a basic reference for the anatomical identification of brain areas localized in human functional brain imaging studies with positron emission tomography (PET). This third dimension provided a vital tool for brain surgery in humans and experimental animals. But today, that model faces serious challenges.Īfter the pioneering work of Brodmann and many others who followed him, a key development in human brain mapping was the introduction of maps using stereotactic coordinates to identify brain regions in three-dimensional space. All our basic concepts have come from specialized investigations by scientists working within this traditional model. The results have been astounding in scope, quality, amount and breadth. Collaborative networks and consortia are forming, often as a result of changes in scientific funding policy, but culturally, even these new groupings remain in the world of the traditional hypothesis-led paradigm. Even today, the world's 100 000 or so neuroscientists work essentially on their own, each developing his or her interest, each using established or innovative methods to dig deeper into one particular corner of the brain. Focus was an essential element for success with grant applications. Neuroscience, basic and clinical, followed the same pattern. Although high-energy physics and astronomy had big teams and expensive instruments-particle accelerators, telescopes-most published research came from highly skilled scientists, working in small laboratories, mostly in the wealthier nations. Thirty years ago, most sciences were craft industries. The brain is an intrinsically multi-scale, multi-level organ operating across spatial scales ranging from nanometres (proteins) to metres (the human body) and temporal scales from picoseconds (atomic interactions) to years (the lifespan of a human being). The models will instantiate principles that govern how the brain is organized at different levels and how different spatio-temporal scales relate to each other in an organ-centred context. This strategy will capitalize on remarkable recent developments in informatics and computer science and on the existence of much existing, addressable data and prior, though fragmented, knowledge. These blueprints will result from analysis of large volumes of neuroscientific and clinical data, by a process of reconstruction, modelling and simulation. We propose that, in the next quarter century, advances in cartography will result in progressively more accurate drafts of a data-led, multi-scale model of human brain structure and function. However, even detailed cartographic data cannot generate knowledge without a multi-scale framework making it possible to relate individual observations and discoveries.
Cartographers continue to collect ever more precise data in the hope that general principles of organization will emerge.
Modern cerebral cartography is assimilating all these elements. Cartographic detail can also be correlated with normal or abnormal psychological or behavioural data. Selective tagging and imaging of molecules adds biochemical contributions.
Temporal information from electrical recordings contributes information on regional interactions adding a functional dimension. Cerebral cartography can be understood in a limited, static, neuroanatomical sense.
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