Neurons in culture show a rich repertorie of activity patterns in which the entire network population particpates. Activity often takes the form of "network bursts", quasi-periodic events of highly coherent activity in which thousands of neurons fire together in a short time window (see MOVIE 1). The mechanisms, both at a neuron and network level, that regulate this activity are not well understood, and are by themselves a focus of strong debate in neuroscience.
In the lab we work with small sized cultures (typically of 3 mm in diameter) to record the spontaneous activity in neuronal cultures using a high-speed, high-resolution camera. We use fluorescence calcium imaging to monitor neuronal firing events across the network, to later understand and model collective behavior in the network.
We consider a different kind of network in which we culture the neurons forming tighly packed assemblies of neurons terned 'clusters' that connect to one another. These networks display a different activity compared to standard, homogeneous cultures (see MOVIE 3), with characteristic sequences of activitation that encompass a sub-set of the clusters' population. Using the time delays of activations within the sequences, we are able to build the functional connectivity of the network, extract its topological features, and compare the structural network (i.e. the actual physical connections between neurons) with the functional one.
- Teller et al., ""Emergence of assortative mixing between clusters of cultured neurons", PLoS Comput. Biol., in press (ArXiv: 1402.4824v2).
- Spontaneous activity in healthy and Sanfilippo's affected cultures.
- Modelling cocaine abuse in dopaminergic neuronal cultures.