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Physiological bases for parasite-induced alterations of host behaviour

Published online by Cambridge University Press:  16 March 2011

S. N. Thompson  and
M. Kavaliers
S. N. Thompson
Affiliation:
Department of Entomology, University of California, Riverside, California, 92521, U.S.A.
M. Kavaliers
Affiliation:
Division of Oral Biology, Faculty of Dentistry and Department of Psychology, University of Western Ontario, London, Ontario, N6A 5C1, Canada
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Summary

Parasitism is defined in various ways as an intimate relationship in which one partner, the parasite, lives on or in another, the host, generally at the expense of the latter. Parasitism commonly results in a unique array of host physiological responses and adaptations. Most studies of the physiological effects of parasitism have focused on the pathological consequence of infection and disease. While many physiological changes contribute to pathogenesis, it is now recognized that parasitic infections at sub-clinical levels also produce physiological effects that either ameliorate or may not contribute to the disease process. Moreover, these physiological changes are often manifested by altered host behaviour. Behavioural studies have enabled an ecological- and evolutionary-oriented evaluation of host responses. In this fashion, physiological effects may be assessed as to whether they affect fitness and confer benefit or harm to one or both of the symbionts involved. We briefly examine how these physiological responses, specifically neural, endocrine, neuromodulatory, and immunomodulatory components, may interact to modify host behaviours. We consider the adaptiveness of these responses and how the behavioural patterns elicited may simultaneously appear adaptive for the parasite as well as the host. In addition, we address how parasite-host physiological and behavioural interactions may be altered during the course of parasitism.

Keywords

Parasiteparasitismbehaviourparasitic castrationsexual selectionpathologyadaptationsexual behaviourhormoneendocrineneuralopioidneuromodulationimmune response
Type
Research Article
Information
Parasitology , Volume 109 , supplement S1: Parasites and behaviour , 1994 , pp. S119 - S138
Copyright
Copyright © Cambridge University Press 1994

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