Modelling the formation of neural circuits
Since the early days of Prof. Santiago Ramón y Cajal it is well known that the intricate branching structures that neurons display are a result of strictly curtailing wiring costs. Modern quantitative analyses have meanwhile strengthened the view that morphologies of axons and dendrites reflect optimal conditions in terms of wiring. However, the consequences of these wiring constraints on neural computation have not been studied in detail.
The goal of this proposal is to study the limitations of wiring onto dendrite and axonal computation as well as computation in defined microcircuits. A realm of novel techniques has recently emerged allowing the dissection of neural circuits at various levels to ultimately obtain the so-called connectome describing all connections in a given brain area. However, when these data will be available, the breadth of these data will render them at first hard to interpret. The studies suggested in this proposal will lead me to identify the features within the connectome data that are direct consequences from wiring constraints. I will uncover principles of wiring in the brain, i.e. what is the connection code? Then, I will study the resulting consequences for computation and function in the nervous system.
The aims of this proposal divide into four work packages studying the functional consequences of wiring costs at various levels:
- How does biology implement wiring optimisation of dendrite growth during development? Can we make sense of live imaging (time-lapse) data of dendrite growth?
- What are the effects of wiring constraints onto dendritic computation? What is the space of possible dendrite types and computational abilities?
- Which constraints lead to the formation of axon tracts and other arrangements of axonal connections? What are their functional limitations?
- What are the general physical limitations of microcircuits and the resulting arrangements? What are putative construction schemes in specific microcircuits such as the cerebellum, dentate gyrus and cerebral cortex?
Dr. Hermann Cuntz