The strings of the puppet master: how parasites change host behavior

Abstract

Parasites can alter a host's behaviour. How they induce such changes remains poorly understood. A neuroscientist trying to control an animal's behaviour typically targets specific neurons or neurotransmitter pathways. However, parasites do not selectively target specific neural circuits, although they may preferentially attack certain brain areas. Most parasitic manipulators induce a variety of neurochemical and neuroimmunological disturbances that are widely distributed across the host's central nervous system. Despite these broad effects, the change in host behaviour is often quite specific. This chapter reviews examples of parasitic manipulation of behaviour in both vertebrates and invertebrates, and concludes with a discussion of how these seemingly broad neurobiological effects might produce specific changes in behaviour.