Slow oscillating population activity in developing cortical networks: models and experimental results

Thomas Baltz, Andreas Herzog, Thomas Voigt
2011 Journal of Neurophysiology  
During early development neuronal networks express slow oscillating synchronized activity. The activity can be driven by several, not necessarily mutually exclusive, mechanisms. Each mechanism might have distinctive consequences for the phenomenology, formation, or sustainment of the early activity pattern. Here we study the emergence of the oscillatory activity in three computational models and multisite extracellular recordings that we obtained from developing cortical networks in vitro. The
more » ... odeled networks consist of leaky integrate-and-fire neurons with adaptation coupled via depressing synapses, which were driven by neurons that are intrinsically bursting, intrinsically random spiking, or driven by spontaneous synaptic activity. The activity of model networks driven by intrinsically bursting cells best matched the phenomenology of 1-wk-old cultures, in which early oscillatory activity has just begun. Intrinsically bursting neurons were present in cortical cultures, but we found them only in those cultures that were younger than 3 wk in vitro. On the other hand, synaptically dependent random spiking was highest after 3 wk in vitro. In conclusion, model networks driven by intrinsically bursting cells show a good approximation of the emergent recurrent population activity in young networks, whereas the activity of more mature networks seems to be better explained by spontaneous synaptic activity. Moreover, similar to previous experimental observations, distributed stimulation in the model was more effective in suppressing population bursts than repeated stimulation of the same neurons. This observation can be explained by an effective depression of a larger fraction of synapses by distributed stimulation. cell culture; development; pacemaker; simulation DURING A LIMITED DEVELOPMENTAL period the electrical activity of neuronal networks is characterized by slow synchronous oscillatory activity, which is widely regarded to play a fundamental role in the establishment of a functional network (Ben-Ari 2001; Feller 1999; Katz and Shatz 1996; O'Donovan 1999) . This activity pattern robustly emerges during the development of various neuronal tissues and in vitro preparations, including the cerebral cortex and hippocampus in vivo (Chiu
doi:10.1152/jn.00889.2010 pmid:21697440 fatcat:sxg7cqwvvbhtfbgumtk5ujhhce