Neuroethological Role of Dynamic Traits of Excitable Cells: A Proposal for the Physiological Basis of Slothfulness in the Sloth

  • Theodore Holmes Bullock


The question I pose in the context of this book is whether the dynamic properties of excitable cells, amply illustrated elsewhere in this volume and in the corpus of work of Susumu Hagiwara, can be of direct neuroethological significance at the level of gross features of vertebrate behavior, for example in causing the slothfulness of the sloth (Bradypus, Edentata), or whether such behavioral anomalies must be explained in terms of system properties, that is emergent properties of constellations of cells. The answer I will come to is affirmative, in the form of a proposition that, for a class of behavioral differences between species, such as the obligate sluggishness of the sloth, cellular properties of large numbers of central neurons do play a large role, but that other mechanisms at several levels of integration also play their roles, for example the balance of modulator substances in local brain regions that exert pervading influences.


Behavioral Difference Excitable Cell Cellular Property Modulator Substance Cell Excitability 
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List of References

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Copyright information

© Springer Science+Business Media New York 1983

Authors and Affiliations

  • Theodore Holmes Bullock
    • 1
  1. 1.Neurobiol. Unit, Scripps Inst. of Oceanography, Dept. of Neurosciences, School of MedicineUniv. of Calif.San Diego, La JollaUSA

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