@article {57891,
	title = {Processing of simple and complex acoustic signals in a tonotopically organized ear},
	year = {2014},
	abstract = {<p>Processing of complex signals in the hearing organ remains poorly understood. This paper aims to contribute to this topic by presenting investigations on the mechanical and neuronal response of the hearing organ of the tropical bushcricket species Mecopoda elongata to simple pure tone signals as well as to the conspecific song as a complex acoustic signal. The high-frequency hearing organ of bushcrickets, the crista acustica (CA), is tonotopically tuned to frequencies between about 4 and 70 kHz. Laser Doppler vibrometer measurements revealed a strong and dominant low-frequency-induced motion of the CA when stimulated with either pure tone or complex stimuli. Consequently, the high-frequency distal area of the CA is more strongly deflected by low-frequency-induced waves than by high-frequency-induced waves. This low-frequency dominance will have strong effects on the processing of complex signals. Therefore, we additionally studied the neuronal response of the CA to native and frequency-manipulated chirps. Again, we found a dominant influence of low-frequency components within the conspecific song, indicating that the mechanical vibration pattern highly determines the neuronal response of the sensory cells. Thus, we conclude that the encoding of communication signals is modulated by ear mechanics.</p>
},
	keywords = {bushcricket, crista acustica, Electrophysiology, insect hearing, laser Doppler vibrometry, Tettigoniidae},
	doi = {10.1098/rspb.2014.1872},
	url = {https://royalsocietypublishing.org/doi/10.1098/rspb.2014.1872https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2014.1872},
	author = {Hummel, Jennifer and Wolf, Konstantin and K{\"o}ssl, Manfred and Nowotny, Manuela}
}
@article {51480,
	title = {Chamber music: an unusual Helmholtz resonator for song amplification in a Neotropical bush-cricket (Orthoptera, Tettigoniidae)},
	journal = {The Journal of Experimental Biology},
	volume = {220},
	year = {2017},
	month = {Sep-15-20172153},
	pages = {2900 - 2907},
	abstract = {<p>Animals use sound for communication, with high-amplitude signals being selected for attracting mates or deterring rivals. High amplitudes are attained by employing primary resonators in sound producing structures to amplify the signal (e.g., avian syrinx). Some species actively exploit acoustic properties of natural structures to enhance signal transmission by using these as secondary resonators (e.g., tree-hole frogs). Male bush-crickets produce sound by tegminal stridulation and often use specialised wing areas as primary resonators. Interestingly, Acanthacara acuta, a Neotropical bush-cricket, exhibits an unusual pronotal inflation, forming a chamber covering the wings. It has been suggested that such pronotal chambers enhance amplitude and tuning of the signal by constituting a (secondary) Helmholtz resonator. If true, the intact system \&ndash; when stimulated sympathetically with broadband sound \&ndash; should show clear resonance around the song carrier frequency which should be largely independent of pronotum material, and change when the system is destroyed. Using laser Doppler vibrometry on living and preserved specimens, micro computed tomography, 3D printed models, and finite element modelling, we show that the pronotal chamber not only functions as a Helmholtz resonator due to its intact morphology but also resonates at frequencies of the calling song on itself, making song production a three-resonator system.</p>
},
	keywords = {acoustic resonator, bioacoustics, bush-cricket, finite element modelling, laser Doppler vibrometry, micro computed tomography},
	issn = {0022-0949},
	doi = {10.1242/jeb.160234},
	url = {http://jeb.biologists.org/lookup/doi/10.1242/jeb.160234},
	author = {Jonsson, Thorin and Robson Brown, Kate and Sarria-S, Fabio A. and Walker, Matthew and Montealegre-Z, Fernando}
}
