Correlations of Cellular Activities in the Nervous System: Physiological and Methodological Considerations

  • Jose Luis Perez Velazquez
  • Ramon Guevara Erra
  • Richard Wennberg
  • Luis Garcia Dominguez
Part of the Springer Series in Computational Neuroscience book series (NEUROSCI, volume 2)


Rhythms (cycles, oscillations) and synchronization processes pervade all aspects of the living and nonliving, from circadian rhythms to individual habits and traits (Glass, 2001; Pikovsky et al., 2001). The distributed nature of cognition implies that distinct brain areas must somehow coordinate their activity: cognition, whether in the form of perception or motor actions, results from the integrated spatiotemporal coordinated activity of cell populations in the nervous system, including both glial and neuronal elements. Because the system’s collective behavior is difficult, if not impossible, to deduce from its individual components, the determination of brain-coordinated activity at adequate levels of description becomes fundamental to the understanding of nervous system function and its relation to behavior. Some questions arise: what variables are best suited to measure these correlations in activity? What order parameters should be used to characterize coordinated activity among cellular populations and how do these activity patterns relate to behavioral responses? What level of description should be used? This chapter summarizes some physiological and methodological considerations to aid the science practitioner in the study of correlated activity patterns in nervous systems.


Phase Difference Functional Connectivity Phase Synchronization Local Field Potential Synaptic Potential 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Our research is supported by the Natural Science and Engineering Research Council of Canada (NSERC), the Hospital for Sick Children Foundation, and the Bial Foundation.


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Jose Luis Perez Velazquez
    • 1
  • Ramon Guevara Erra
    • 2
  • Richard Wennberg
    • 3
  • Luis Garcia Dominguez
    • 2
  1. 1.Neurosciences and Mental Health Program, Division of Neurology, Department of Paediatrics and Institute of Medical Science, Brain and Behaviour Centre, Hospital for Sick ChildrenUniversity of TorontoTorontoCanada
  2. 2.Hospital for Sick ChildrenUniversity of TorontoTorontoCanada
  3. 3.Clinical Neurophysiology Laboratory, Krembil Neuroscience Centre, Toronto Western HospitalUniversity Health Network, University of TorontoTorontoCanada

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