Focal laser energy illuminates strain sensing in insect wings


Meeting Abstract

P2-165  Friday, Jan. 6 15:30 – 17:30  Focal laser energy illuminates strain sensing in insect wings PRATT, B*; MOHREN, T; DEORA, T; NJONGE, A; DANIEL, T; Univ. of Washington, Seattle danielt@uw.edu http://faculty.washington.edu/danielt/index.html

Animals rely on multiple sensory modalities to accomplish challenging sensorimotor tasks. Insects use a combination of vision, olfaction, and mechanosensation to control their rapid and complex flight maneuvers. While flight control largely depends on visual feedback, visual processing speeds are often too slow to support rapid flight responses. As such, flying insects use the faster mechanosensory modes to facilitate rapid and dynamic responses to perturbations. In particular, insect wings serve this mechanosensory function. They are richly imbued with patches of bell shaped strain sensors called campaniform sensilla. How campaniform sensilla extract and process strain information remains an open question. To address this question, we focused on campaniform sensilla on the wings of the hawk moth, Manduca sexta. We recorded the neural response to band-limited white noise mechanical stimuli and identified single neural units via spike sorting methods. Simultaneously, we recorded the wing motion using multi-camera high speed videography and reconstructed the spatial and temporal patterns of strain associated with the mechanical stimulus. Using the thermosensitive property of the mechanosensors, we applied local laser heating to map the receptive region on the wing for each identified neuron. This novel technique allowed us to compute the local strains experienced by each sensillum. We found that these strain sensors encode mechanical information rapidly (spike timing precision of between 2 and 10 ms) and with high selectivity (preferentially encoding stimuli closely resembling particular stimulus features) This suggests wing strain sensing is a critical component of the control system in flying insects.

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