Modelling circadian cycles, jet-lag and social jet-lag in mammals

• Grant number: 18/22140-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: February 01, 2019
• End date: January 31, 2021
• Field of knowledge: Physical Sciences and Mathematics - Physics - General Physics
• Principal Investigator: Iberê Luiz Caldas
• Grantee: Flávia Mayumi Ruziska Hirata
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 18/03211-6 - Non linear dynamics, AP.TEM

Abstract

Circadian cycles exist in all phylogenetic scale. In mammals they are controlled mainly by the suprachiasmatic nucleus (SNC). Changes in the environment may generate misalignments between the natural circadian cycles and the external cues. For instance, this occurs in long trips over several time-zones (jet-lag) and in nocturnal shifts of work (social jet-lag). In this work, we aim to extend the knowledge about how changes in the coupling between the neurons can interfer on the recovery of jet-lag using techniques from Physics, more specifically from non-linear dynamics, complex systems and stochastic physics. We will work with models of low dimensionality , that can be either defined directely or deduced of high dimensional models using techiniques as the Ott-Antosen Ansatz. In these models the interpretations of the relevance of each part of the model will be clearer since the they are simpler. We also will work with models of high dimensionality considering the equations for the 10.000 neurons that form the SNC. The advantange in this case is that it's easier to associate the componetns of the model to the physiologic process, with the increase in the complexity will the results will be numerical and they will demand high computacional power. In a second stage we will consider stochastic fluctuations on the couplings between neurons. We will develop this research in colaboration with profª Drª Gisele Akemi Oda of Instituto de Biociências of USP.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

RUZISKA, FLAVIA M.; CALDAS, IBERE L.. Synchronization and attractors in a model simulating social jetlag. CHAOS SOLITONS & FRACTALS, v. 144, MAR 2021. (18/22140-2, 18/03211-6)