Disproportionate frequency representation in the inferior colliculus of doppler-compensating Greater Horseshoe bats: Evidence for an acoustic fovea

@article{Schuller2004DisproportionateFR,
  title={Disproportionate frequency representation in the inferior colliculus of doppler-compensating Greater Horseshoe bats: Evidence for an acoustic fovea},
  author={Gerd Schuller and George D. Pollak},
  journal={Journal of comparative physiology},
  year={2004},
  volume={132},
  pages={47-54}
}
Summary1.The inferior colliculus of 8 Greater Horseshoe bats (Rhinolophus ferrumequinun) was systematically sampled with electrode penetrations covering the entire volume of the nucleus. The best frequencies and intensity thresholds for pure tones (Fig. 2) were determined for 591 neurons. The locations of the electrode penetrations within the inferior colliculus were histologically verified.2.About 50% of all neurons encountered had best frequencies (BF) in the frequency range between 78 and 88… 

Single unit responses to linear frequency-modulations in the inferior colliculus of the Greater horseshoe bat,Rhinolophus ferumequinum

  • M. Vater
  • Biology
    Journal of comparative physiology
  • 2005
The majority of single units studied had minimum thresholds that were either equal for CF- and FM-signals of the same duration or lower for the CF-stimulus, andhibition was frequently observed with FM-stimuli in spontaneously active neurons.

Frequency tuning and latency organization of responses in the inferior colliculus of Japanese house bat, Pipistrellus abramus.

Electrophysiological measures suggest the importance of a target distance within approximately 3 m, which is consistent with behavioral measures during foraging in this species.

Auditory properties of the superior colliculus in the horseshoe bat, Rhinolophus rouxi

  • K. Reimer
  • Biology
    Journal of Comparative Physiology A
  • 2004
The most striking finding in the horseshoe bat was an enormous overrepresentation of neurons with best frequencies in the range of the constant frequency component of the species specific echolocation call (72% of the auditory neurons).

Echolocation Calls and Neurophysiological Correlations with Auditory Response Properties in the Inferior Colliculus of Pipistrellus abramus (Microchiroptera: Vespertilionidae)

The study of echolocation calls and auditory response properties of IC neurons suggests that the IC of P. abramus can effectively process emitted pulses and echoes during hunting.

Ontogenesis of auditory fovea representation in the inferior colliculus of the Sri Lankan rufous horseshoe bat, Rhinolophus rouxi

The results confirm the hypothesis of developmental shifts in the frequency-place code for the foveal high frequency representation in the IC of the rufous horseshoe bat and follow a low-to-high frequency gradient.

Comparative collicular tonotopy in two bat species adapted to movement detection,Hipposideros speoris andMegaderma lyra

It is suggested that pure tone echolocation and auditory foveae are primarily adaptations to echo clutter rejection for species foraging on the wing close to vegetation.

Tonotopical organization and pure tone response characteristics of single units in the auditory cortex of the Greater Horseshoe Bat

  • J. Ostwald
  • Biology
    Journal of Comparative Physiology A
  • 2004
This finding is in contradiction to the current opinion that frequency representation in the auditory system of Horseshoe Bats is only determined by the mechanical tuning properties of the basilar membrane.

The nuclei of the lateral lemniscus in the rufous horseshoe bat,Rhinolophus rouxi

The ventral nucleus of the lateral lemniscus was characterized by a remarkably high proportion of neurons having best frequencies in the filter frequency range, and a tonotopic arrangement of units was found in the intermediate nucleus with units having high best frequencies located medially and those with low best frequencies laterally.

Coding of sinusoidally amplitude modulated acoustic stimuli in the inferior colliculus of the rufous horseshoe bat,Rhinolophus rouxi

  • K. Reimer
  • Biology
    Journal of Comparative Physiology A
  • 2004
The results did not reveal any significant specialization of the bat's auditory system for coding of amplitude modulations as compared to other mammals.
...

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  • Biology
    Journal of comparative physiology
  • 2004
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