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

Becoming a grower: World view transformation among committed members of a mutual help group

This was a study of world view transformation among committed members of a 12 Step mental health mutual help group called GROW. The purpose of the study was to explore and further our understanding of the phenomenon of world view transformation by listening to the stories of committed members of a mutual help group. More specifically, the research question was: How do committed members of the mutual help group, GROW, describe their own world view transformation? I focused particularly on personal testimonies and epiphanies and how members incorporated the group's world view as their own.I used an interpretive, qualitative approach which involved participant observation in the group and interviewing group members. The interview was focused on hearing the personal testimonies of group members. Based on analysis of the interview transcripts I wrote personal stories for each group member.I performed an interpretive analysis across the stories and developed eight themes. Four of the themes deal with stages of affiliation with the group: lead up to GROW, first contact with GROW, leadership in GROW, and life beyond GROW. Four of the themes deal with changes in beliefs in specific domains: beliefs about self, beliefs about others, beliefs about spirituality, beliefs about mental health. Overall, group members described changes in their beliefs related to each of the stages of affiliation and in each of the domains. The Growers described that the alternative world view which GROW offered to them, particularly concerning the definition and resolution of their mental health problems, opened up a new life path for them which led to self-esteem through ordinariness, active participation in their own recovery, friendship with others, and a belief in a higher meaning in their lives in spite of and perhaps even through their problems.I concluded with a summary of the changes in world view transformation particularly as related to an alternative definition and resolution of the problem of mental illness. I discussed issues for further research including cross-group and cross-cultural studies, and the relationship between professionals and members of mutual help groups.U of I OnlyETDs are only available to UIUC Users without author permissio