25th annual computational neuroscience meeting: CNS-2016

The same neuron may play different functional roles in the neural circuits to which it belongs. For example, neurons in the Tritonia pedal ganglia may participate in variable phases of the swim motor rhythms [1]. While such neuronal functional variability is likely to play a major role the delivery of the functionality of neural systems, it is difficult to study it in most nervous systems. We work on the pyloric rhythm network of the crustacean stomatogastric ganglion (STG) [2]. Typically network models of the STG treat neurons of the same functional type as a single model neuron (e.g. PD neurons), assuming the same conductance parameters for these neurons and implying their synchronous firing [3, 4]. However, simultaneous recording of PD neurons shows differences between the timings of spikes of these neurons. This may indicate functional variability of these neurons. Here we modelled separately the two PD neurons of the STG in a multi-neuron model of the pyloric network. Our neuron models comply with known correlations between conductance parameters of ionic currents. Our results reproduce the experimental finding of increasing spike time distance between spikes originating from the two model PD neurons during their synchronised burst phase. The PD neuron with the larger calcium conductance generates its spikes before the other PD neuron. Larger potassium conductance values in the follower neuron imply longer delays between spikes, see Fig. 17.Neuromodulators change the conductance parameters of neurons and maintain the ratios of these parameters [5]. Our results show that such changes may shift the individual contribution of two PD neurons to the PD-phase of the pyloric rhythm altering their functionality within this rhythm. Our work paves the way towards an accessible experimental and computational framework for the analysis of the mechanisms and impact of functional variability of neurons within the neural circuits to which they belong

26th Annual Computational Neuroscience Meeting (CNS*2017): Part 3 - Meeting Abstracts - Antwerp, Belgium. 15–20 July 2017

This work was produced as part of the activities of FAPESP Research,\ud Disseminations and Innovation Center for Neuromathematics (grant\ud 2013/07699-0, S. Paulo Research Foundation). NLK is supported by a\ud FAPESP postdoctoral fellowship (grant 2016/03855-5). ACR is partially\ud supported by a CNPq fellowship (grant 306251/2014-0)

Ancient Near Eastern Passports: Two Stamp Seals from Khirbet Qeiyafa; Martin G. Klingbeil, DLitt; February 15, 2012

In the ancient world, stamp seals served as a tool for identification, a symbol of socioeconomic status, and a venue for personal expression. They were a platform for communication and diversification. Throughout the excavations at Khirbet Qeiyafa, several stamp seals have been found. If these seals could talk, what would they say? Which stories would they share about the people who lived long ago? Could these seals help illuminate gaps of ambiguity within the archaeological record? In this lecture, Martin G. Klingbeil, PhD, invites viewers into the processes used to uncover the meaning of stamp seals. In doing so, he applies his research to the latest stamp seal findings at Qeiyafa and how possible interpretations of the stamp seals impact research. Martin Klingbeil (DLitt 1995, Stellenbosch University) is a professor of Biblical Studies and Archaeology at Southern, as well as the associate director of its Institute of Archaeology. He is currently co-director for The Fourth Expedition to Lachish.https://knowledge.e.southern.edu/arch_museum_lectures/1017/thumbnail.jp