The following bioacoustics-related articles have been recently published
in the "Journal of Comparative Psychology", Vol. 120 (3), August 2006:
Relationship Between Paw Preference Strength and Noise Phobia in Canis
familiaris . Branson, N. J.; Rogers, L. J.; Journal of Comparative
Psychology. Vol. 120(3) August 2006. pp. 176-183.
The authors investigated the relationship between degree of lateralization
and noise phobia in 48 domestic dogs (Canis familiaris) by scoring paw
preference to hold a food object and relating it to reactivity to the
sounds of thunderstorms and fireworks, measured by playback and a
questionnaire. The dogs without a significant paw preference were
significantly more reactive to the sounds than the dogs with either a
left-paw or right-paw preference. Intense reactivity, therefore, is
associated with a weaker strength of cerebral lateralization. The authors
note the similarity between their finding and the weaker hand preferences
shown in humans suffering extreme levels of anxiety and suggest neural
mechanisms that may be involved.
Frequency-Range Discriminations and Absolute Pitch in Black-Capped
Chickadees (Poecile atricapillus), Mountain Chickadees (Poecile gambeli),
and Zebra Finches (Taeniopygia guttata) . Lee, Tiffany T. Y.; Charrier,
Isabelle; Bloomfield, Laurie L.; Weisman, Ronald G.; Sturdy, Christopher
B.; Journal of Comparative Psychology. Vol. 120(3) August 2006. pp.
217-228.
The acoustic frequency ranges in birdsongs provide important absolute
pitch cues for the recognition of conspecifics. Black-capped chickadees
(Poecile atricapillus), mountain chickadees (Poecile gambeli), and zebra
finches (Taeniopygia guttata) were trained to sort tones contiguous in
frequency into 8 ranges on the basis of associations between response to
the tones in each range and reward. All 3 species acquired accurate
frequency-range discriminations, but zebra finches acquired the
discrimination in fewer trials and to a higher standard than black-capped
or mountain chickadees, which did not differ appreciably in the
discrimination. Chickadees' relatively poorer accuracy was traced to
poorer discrimination of tones in the higher frequency ranges. During
transfer tests, the discrimination generalized to novel tones when the
training tones were included, but not when they were omitted.
The Discrimination of Temporal Fine Structure in Call-Like Harmonic Sounds
by Birds . Lohr, Bernard; Dooling, Robert J.; Bartone, Suzanne; Journal of
Comparative Psychology. Vol. 120(3) August 2006. pp. 239-251.
Thresholds for discriminating changes in the temporal fine structure of
call-like, harmonic sounds were measured in zebra finches (Taeniopygia
guttata) and budgerigars (Melopsittacus undulatus). Birds could detect
changes in periods as short as 1.225 ms at near 100% accuracy even when
spectral and envelope cues were identical, as in time-reversed stimuli.
Humans performed poorly on such stimuli, paralleling results from previous
studies. Bird thresholds were in the range of those reported in
neurophysiological studies of the songbird high vocal center (HVC) to
temporally modified conspecific songs. Taken together, these results show
that birds can hear differences in temporal fine structure in their
natural vocalizations that go beyond human capabilities, but whether these
abilities have communicative relevance remains to be seen.
With best regards,
Lidia Eva Wysocki
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Dr. Lidia Eva Wysocki
Department of Biology,
University of Maryland
20742 College Park, MD
USA
phone: ++1 301 405 6903
email:
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