Rickye S. Heffner

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The behavioral audiogram of the hooded Norway rat was determined for frequencies from 250 Hz to 70 kHz. The resulting audiogram is virtually identical to the albino rat audiogram obtained by Kelly and Masterton (1977), indicating that there is no detectable effect of albinism on the audiogram of the Norway rat. The two audiograms also indicate the degree of(More)
The audiograms of three big brown bats (Eptesicus fuscus) were determined using a conditioned avoidance procedure. The average audiogram ranged from 0.850 kHz at 106 dB to 120 kHz at 83 dB SPL, with a best threshold of 7 dB at 20 kHz and a distinct decrease in sensitivity at 45 kHz. The results confirm those of a previous study by Dalland (1965a) that the(More)
A young Indian elephant was tested to determine its absolute sensitivity, frequency-discrimination thresholds, and sound-localization thresholds. The elephant was found to have an audibility curve similar to that of other mammals but one that is more sensitive to low frequencies and less sensitive to high frequencies than any other mammalian audiogram(More)
We determined the audiogram of Phyllostomus hastatus (the greater spear-nosed bat), a large, omnivorous American leaf-nosed bat native to Central and South America. A conditioned suppression/avoidance procedure with a fruit juice reward was used for testing. At an intensity of 60 dB sound pressure level (SPL re 20 microN/m(2)), the hearing range of P.(More)
1. The ability of four Japanese macaques (Macaca fuscata) to localize sound was determined after bilateral ablation of auditory cortex. The animals were given two tests: a "midline" test in which they had to discriminate noise bursts presented from a loudspeaker located to the left from identical noise bursts presented from a loudspeaker located to the(More)
Behavioral audiograms were determined for five species of rodents: groundhog (Marmota monax), chipmunk (Tamias striatus), Darwin's leaf-eared mouse (Phyllotis darwinii), golden hamster (Mesocricetus auratus), and Egyptian spiny mouse (Acomys cahirinus). The high-frequency hearing of these animals was found to vary inversely with interaural distance, a(More)
Behavioral tests of absolute sensitivity and sound localization in African naked mole rats show that, despite their communal social structure and large vocal repertoire, their hearing has degenerated much like that of other subterranean species. First, their ability to detect sound is limited, with their maximum sensitivity being only 35 dB (occurring at 4(More)
We determined the audiograms of two short-tailed fruit bats (Carollia perspicillata), 18-g phyllostomids from Central and South America. For testing, we used a conditioned suppression/avoidance procedure with a fruit juice reward. At an intensity of 60 dB SPL, the hearing of C. perspicillata extends from 5.2 to 150 kHz, showing a best sensitivity of 0 dB at(More)
Potential auditory compensation in neonatally bilaterally enucleated Syrian hamsters was explored anatomically, electrophysiologically and behaviourally. Gross morphology of the visual cortex appeared normal and no obvious cytoarchitectural malformation was discerned. However, enucleation induced a significant increase in the spontaneous firing rate of(More)