On Episode Sensitization in Recurrent Affective Disorders: The Role of Noise

Department of Psychiatry and Psychotherapy, University of Marburg, Rudolf-Bultmannstrasse 8, D-35033 Marburg, Germany.
Neuropsychopharmacology (Impact Factor: 7.05). 08/2003; 28 Suppl 1(7):S13-20. DOI: 10.1038/sj.npp.1300141
Source: PubMed


Episode sensitization is postulated as a key mechanism underlying the long-term course of recurrent affective disorders. Functionally, episode sensitization represents positive feedback between a disease process and its disease episodes resulting in a transition from externally triggered to autonomous episode generation. Recently, we introduced computational approaches to elucidate the functional properties of sensitization. Specifically, we considered the dynamics of episode sensitization with a simple computational model. The present study extends this work by investigating how naturally occurring, internal or external, random influences ("noise") affect episode sensitization. Our simulations demonstrate that actions of noise differ qualitatively in dependence on both the model's activity state as well as the noise intensity. Thereby induction as well as suppression of sensitization can be observed. Most interestingly, externally triggered sensitization development can be minimized by tuning the noise to intermediate intensities. Our findings contribute to the conceptual understanding of the clinical kindling model for affective disorders and also indicate interesting roles for random fluctuations in kindling and sensitization at the neuronal level.

Download full-text


Available from: Hans Albert Braun,
18 Reads
  • Source
    • "Networks of synchronous neurons (Pereira et al., 2007; Batista et al., 2013; Wu et al., 2013; Shi et al., 2009; Torrealdea et al., 2009) in particular, have become of great interest due to a multitude of related neurological pathologies. These include Parkinson's disease (Park et al., 2011), epilepsy (Heilman and Quattrochi, 2004; Huber et al., 2003), seizures (Takeshita and Bahar, 7506), depression (Johnstone, 2007), schizophrenia (Brenner et al., 2003) and sleep disorders (Fulcher et al., 2014). In addition, neural firing regime transitions in the context of synchronization are ubiquitous and of relevance to a number of physiological functions. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Central pattern generators are neuron networks that produce vital rhythmic motor outputs such as those observed in mastication, walking and breathing. Their activity patterns depend on the tuning of their intrinsic ionic conductances, their synaptic interconnectivity and entrainment by extrinsic neurons. The influence of two commonly found synaptic connectivities - reciprocal inhibition and electrical coupling - are investigated here using a neuron model with subthreshold oscillation capability, in different firing and entrainment regimes. We study the dynamics displayed by a network of a pair of neurons with various firing regimes, coupled by either (i) only reciprocal inhibition or by (ii) electrical coupling first and then reciprocal inhibition. In both scenarios a range of coupling strengths for the reciprocal inhibition is tested, and in general the neuron with the lower firing rate stops spiking for strong enough inhibitory coupling, while the faster neuron remains active. However, in scenario (ii) the originally slower neuron stops spiking at weaker inhibitory coupling strength, suggesting that the electrical coupling introduces an element of instability to the two-neuron network.
    Biosystems 11/2014; 127:73-83. DOI:10.1016/j.biosystems.2014.11.002 · 1.55 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Affective disorders tend to be recurrent and progressive and illness patterns typically evolve from isolated episodes at the beginning to more rapid, rhythmic and finally irregular "chaotic" mood patterns. Chararacteristic timecourse and disease patterns have prompted the consideration of nonlinear dynamics and chaos. In this paper we review some of our recent work where we addressed the relevance of nonlinear, stochastic and resulting cooperative dynamics for disease patterns and temporal course of affective disorders by use of a computational approach.
    International Journal of Bifurcation and Chaos 02/2004; 14(2):635-652. DOI:10.1142/S021812740400934X · 1.08 Impact Factor
  • Journal of Critical Care 12/2005; 20(4):384-384. DOI:10.1016/j.jcrc.2005.09.021 · 2.00 Impact Factor
Show more