Elsevier

Current Opinion in Neurobiology

Volume 43, April 2017, Pages 110-118
Current Opinion in Neurobiology

Multisensory integration in C. elegans

https://doi.org/10.1016/j.conb.2017.01.005Get rights and content

Highlights

  • C. elegans performs multisensory integration.

  • C. elegans nervous system uses polymodal sensory neurons or combination of different sensory neurons to perceive multisensory cues.

  • C. elegans nervous system uses circuit motifs of defined properties, such as coincidence detector and hub-and-spoke circuits, to process multisensory integration.

  • C. elegans nervous system uses neuromodulators to regulate multisensory integration.

Multisensory integration is a neural process by which signals from two or more distinct sensory channels are simultaneously processed to form a more coherent representation of the environment. Multisensory integration, especially when combined with a survey of internal states, provides selective advantages for animals navigating complex environments. Despite appreciation of the importance of multisensory integration in behavior, the underlying molecular and cellular mechanisms remain poorly understood. Recent work looking at how Caenorhabditis elegans makes multisensory decisions has yielded mechanistic insights into how a relatively simple and well-defined nervous system employs circuit motifs of defined features, synaptic signals and extrasynaptic neurotransmission, as well as neuromodulators in processing and integrating multiple sensory inputs to generate flexible and adaptive behavioral outputs.

Section snippets

C. elegans performs multisensory integration

All animals navigate in complex natural environments that contain both dangers and valuable sources, such as predators and food. Many of these sources are represented by more than one sensory cue. Thus, animals need to process multiple sensory cues in order to make decisions that benefit survival and reproduction. Behavioral paradigms used to investigate multisensory integration in C. elegans have been developed by taking advantage of the sensitivity of the worms to an array of sensory

Polymodal sensory neurons

Sensory neurons in C. elegans have the capability to be what is referred to as ‘polymodal’ [28]. This has been demonstrated for many of the sensory neurons using optical imaging, laser/genetic ablation and behavioral analysis, such as the ASH sensory neurons that have been shown to respond to an array of aversive stimuli of different modalities, including mechanosensation, noxious stimuli, pH, quinine, and food odors to direct sensorimotor responses [13, 19, 20, 27•, 29, 30, 31, 32, 33, 34•, 35

Functional significance of multisensory integration

Overall, we have reviewed a number of multisensory integration behaviors and possible underlying mechanisms in C. elegans (Figure 1). Together, these studies suggest that multisensory integration can take place at different layers of the nervous system using synaptic and non-synaptic communication under various contexts. Here, we propose several important functional consequences of multisensory integration. First, integrating sensory cues of multiple modalities allows animals to better extract

Conflict of interest statement

Nothing declared.

References and recommended reading

Papers of particular interest, published within the period of review, have been highlighted as:

  • • of special interest

Acknowledgments

D.D.G. was supported by a National Institute of Neurological Disease and Stroke (NINDS) National Institutes of Health (NIH) Predoctoral Fellowship (F31NS080628). Work in the laboratory of M.N.N. was supported in part by NINDS, NIH (R01NS056443, R01NS091070) and National Institute of General Medical Sciences, NIH (R01GM098931). Work in the laboratory of Y.Z. is supported in part by The National Institute on Deafness and Other Communication Disorders, NIH (R01DC009852) and National Institute of

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    These authors contributed equally to this work.

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