25th Annual Computational Neuroscience Meeting: CNS-2016

Abstracts of the 25th Annual Computational Neuroscience Meeting: CNS-2016 Seogwipo City, Jeju-do, South Korea. 2–7 July 201

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

Influence of ship design and operational factors on human performance and evaluation of effects and sensitivity using risk models

This paper presents research results on the causes and effects of human errors in relation to typical ship design factors, such as noise, vibrations and ship motions. Following a review of the relevant literature, aimed to the identification and quantification of pertinent parameters and effects, a detailed questionnaire has been developed and answered by seafarers. The questionnaire results are presented in the form of quantitative risk models, using Bayesian networks with applications on two safety-critical ships, namely containerships and tankers. Finally, we present the generic collision and grounding causation probabilities for both ship types. The results are found to be in good agreement with current literature. Knowledge of the ship design factor effects on the human performance in quantitative form would be useful in the ship design and the development of new safety rules and regulations

Problems of human-computer interaction in cyberworlds

Created intentionally or spontaneously, cyberworlds are information spaces and communities that immensely augment the way we interact, participate in business and receive information throughout the world. This paper reports position statements presented at the plenary panel of the 2015th International Conference on Cyberworlds. First, the problems of enhancing creativity in cyberworlds using new interfaces are considered. It follows by the discussions on using biometric interfaces in on-line services. Finally, the challenges of using braincomputer interfaces and emotion recognition using electroencephalograms are considered

Towards a definition of virtual objects with Partial Differential Equations

NoWe propose an efficient alternative to commonly used parametric surfaces such as NURBS surfaces for definition of complex geometry in shared virtual spaces. Our mathematical model allows to define objects by only providing coordinates of the section curves in 3-space. The resulting parametric functions allow fast calculation of the coordinates of the points on the surface of the objects. We devise an algorithm which evaluates the coefficients of these functions in real time. Given the small size of the resulting formulas and interactive rates for their calculation, we are able to efficiently use such PDE-based models for making virtual objects in shared virtual spaces. We describe the modeling framework and illustrate the proposed theoretical concepts with our function-based extension of VRML and X3D