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Moving beyond Type I and Type II neuron types
1Toronto Western Research Institute, University Health Network, Toronto, ONT, Canada ; Departments of Medicine (Neurology) and Physiology, University of Toronto, Toronto, ONT, Canada.
Abstract:
In 1948, Hodgkin delineated different classes of axonal firing. This has been mathematically translated allowing insight and understanding to emerge. As such, the terminology of 'Type I' and 'Type II' neurons is commonplace in the Neuroscience literature today. Theoretical insights have helped us realize that, for example, network synchronization depends on whether neurons are Type I or Type II. Mathematical models are precise with analyses (considering Type I/II aspects), but experimentally, the distinction can be less clear. On the other hand, experiments are becoming more sophisticated in terms of distinguishing and manipulating particular cell types but are limited in terms of being able to consider network aspects simultaneously. Although there is much work going on mathematically and experimentally, in my opinion it is becoming common that models are either superficially linked with experiment or not described in enough detail to appreciate the biological context. Overall, we all suffer in terms of impeding our understanding of brain networks and applying our understanding to neurological disease. I suggest that more modelers become familiar with experimental details and that more experimentalists appreciate modeling assumptions. In other words, we need to move beyond our comfort zones.
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