@article{KoesslHechavarriaVossetal.2015, author = {K{\"o}ssl, Manfred and Hechavarria, Julio and Voss, Cornelia and Schaefer, Markus and Vater, Marianne}, title = {Bat auditory cortex - model for general mammalian auditory computation or special design solution for active time perception?}, series = {European journal of neuroscience}, volume = {41}, journal = {European journal of neuroscience}, number = {5}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0953-816X}, doi = {10.1111/ejn.12801}, pages = {518 -- 532}, year = {2015}, abstract = {Audition in bats serves passive orientation, alerting functions and communication as it does in other vertebrates. In addition, bats have evolved echolocation for orientation and prey detection and capture. This put a selective pressure on the auditory system in regard to echolocation-relevant temporal computation and frequency analysis. The present review attempts to evaluate in which respect the processing modules of bat auditory cortex (AC) are a model for typical mammalian AC function or are designed for echolocation-unique purposes. We conclude that, while cortical area arrangement and cortical frequency processing does not deviate greatly from that of other mammals, the echo delay time-sensitive dorsal cortex regions contain special designs for very powerful time perception. Different bat species have either a unique chronotopic cortex topography or a distributed salt-and-pepper representation of echo delay. The two designs seem to enable similar behavioural performance.}, language = {en} } @article{KoesslVossMoraetal.2012, author = {K{\"o}ssl, Manfred and Voss, Cornelia and Mora, Emanuel C. and Macias, Silvio and F{\"o}ller, Elisabeth and Vater, Marianne}, title = {Auditory cortex of newborn bats is prewired for echolocation}, series = {Nature Communications}, volume = {3}, journal = {Nature Communications}, number = {2}, publisher = {Nature Publ. Group}, address = {London}, issn = {2041-1723}, doi = {10.1038/ncomms1782}, pages = {7}, year = {2012}, abstract = {Neuronal computation of object distance from echo delay is an essential task that echolocating bats must master for spatial orientation and the capture of prey. In the dorsal auditory cortex of bats, neurons specifically respond to combinations of short frequency-modulated components of emitted call and delayed echo. These delay-tuned neurons are thought to serve in target range calculation. It is unknown whether neuronal correlates of active space perception are established by experience-dependent plasticity or by innate mechanisms. Here we demonstrate that in the first postnatal week, before onset of echolocation and flight, dorsal auditory cortex already contains functional circuits that calculate distance from the temporal separation of a simulated pulse and echo. This innate cortical implementation of a purely computational processing mechanism for sonar ranging should enhance survival of juvenile bats when they first engage in active echolocation behaviour and flight.}, language = {en} } @article{HechavarriaMaciasVateretal.2013, author = {Hechavarria, Julio C. and Macias, Silvio and Vater, Marianne and Mora, Emanuel C. and K{\"o}ssl, Manfred}, title = {Evolution of neuronal mechanisms for echolocation specializations for target-range computation in bats of the genus Pteronotus}, series = {The journal of the Acoustical Society of America}, volume = {133}, journal = {The journal of the Acoustical Society of America}, number = {1}, publisher = {American Institute of Physics}, address = {Melville}, issn = {0001-4966}, doi = {10.1121/1.4768794}, pages = {570 -- 578}, year = {2013}, abstract = {Delay tuning was studied in the auditory cortex of Pteronotus quadridens. All the 136 delay-tuned units that were studied responded strongly to heteroharmonic pulse-echo pairs presented at specific delays. In the heteroharmonic pairs, the first sonar call harmonic marks the timing of pulse emission while one of the higher harmonics (second or third) indicates the timing of the echo. Delay-tuned units are organized chronotopically along a rostrocaudal axis according to their characteristic delay. There is no obvious indication of multiple cortical axes specialized in the processing of different harmonic combinations of pulse and echo. Results of this study serve for a straight comparison of cortical delay-tuning between P. quadridens and the well-studied mustached bat, Pteronotus parnellii. These two species stem from the most recent and most basal nodes in the Pteronotus lineage, respectively. P. quadridens and P. parnellii use comparable heteroharmonic target-range computation strategies even though they do not use biosonar calls of a similar design. P. quadridens uses short constant-frequency (CF)/frequency-modulated (FM) echolocation calls, while P. parnellii uses long CF/FM calls. The ability to perform "heteroharmonic" target-range computations might be an ancestral neuronal specialization of the genus Pteronotus that was subjected to positive Darwinian selection in the evolution.}, language = {en} } @article{VaterFoellerMoraetal.2010, author = {Vater, Marianne and Foeller, Elisabeth and Mora, Emanuel C. and Coro, Frank and Russell, Ian J. and K{\"o}ssl, Manfred}, title = {Postnatal maturation of primary auditory cortex in the mustached bat, pteronotus parnellii}, issn = {0022-3077}, doi = {10.1152/jn.00517.2009}, year = {2010}, abstract = {The primary auditory cortex (AI) of adult Pteronotus parnellii features a foveal representation of the second harmonic constant frequency (CF2) echolocation call component. In the corresponding Doppler-shifted constant frequency (DSCF) area, the 61 kHz range is over-represented for extraction of frequency-shift information in CF2 echoes. To assess to which degree AI postnatal maturation depends on active echolocation or/and reflects ongoing cochlear maturation, cortical neurons were recorded in juveniles up to postnatal day P29, before the bats are capable of active foraging.At P1-2, neurons in posterior AI are tuned sensitively to low frequencies (22-45 dB SPL, 28-35 kHz). Within the prospective DSCF area, neurons had insensitive responses (>60 dB SPL) to frequencies <40 kHz and lacked sensitive tuning curve tips. Up to P10, when bats do not yet actively echolocate, tonotopy is further developed and DSCF neurons respond to frequencies of 51-57 kHz with maximum tuning sharpness (Q(10dB)) of 57. Between P11 and 20, the frequency representation in AI includes higher frequencies anterior and dorsal to the DSCF area. More multipeaked neurons (33\%) are found than at older age. In the oldest group, DSCF neurons are tuned to frequencies close to 61 kHz with Q(10dB) values <= 212, and threshold sensitivity, tuning sharpness and cortical latencies are adult-like. The data show that basic aspects of cortical tonotopy are established before the bats actively echolocate. Maturation of tonotopy, increase of tuning sharpness, and upward shift in the characteristic frequency of DSCF neurons appear to strongly reflect cochlear maturation.}, language = {en} } @article{KoesslMoraCoroetal.1999, author = {K{\"o}ssl, Manfred and Mora, Emanuel C. and Coro, Frank and Vater, Marianne}, title = {Two-toned echolocation calls from Molossus molossus in Cuba.}, issn = {0022-2372}, year = {1999}, language = {en} } @article{KoesslVater2000, author = {K{\"o}ssl, Manfred and Vater, Marianne}, title = {Consequences of outer hair cell damage for otoacoustic emissions and audiovocal feedback in the mustached bat}, issn = {1525-3961}, year = {2000}, language = {en} } @article{FoellerVaterKoessl2001, author = {Foeller, Elisabeth and Vater, Marianne and K{\"o}ssl, Manfred}, title = {Laminar analysis of inhibition in the gerbil primary auditory cortex.}, issn = {1525-3961}, year = {2001}, language = {en} }