E. V. Korneeva, L. I. Aleksandrov, T. B. Golubeva and V. V. Raevskii (2006):
Development of the auditory sensitivity and formation of the acoustically
guided defensive behavior in nestlings of the pied flycatcher Ficedula
hypoleuca. Journal Of Evolutionary Biochemistry And Physiology, 42/6,
691-698
Abstract: Age dynamics of generation of the evoked potentials (EP) in the
field L of caudal nidopallium (the higher integrative center of the avian
auditory system) and development of the auditory-guided defensive behavior
were studied in control and visually deprived pied flycatcher Ficedula
hypoleuca nestlings. It was shown that the rhythmically organized
monofrequency signals with sound frequency 3.5 kHz and higher produced the
defensive behavior as the auditory sensitivity to these frequencies matured.
After 9 days, the species-specific alarm signal produced more effectively
the defensive behavior than the tonal signals. The rhythmically organized
sound with filling frequency 0.5 kHz, occupying the less low-frequency
diapason than the feeding signal, produced the effect opposite to the alarm
signal to increase the nestling mobility. At the initial stage of the
defensive behavior development the auditory threshold fell markedly in the
frequency diapason corresponding to the frequency diapason of the alarm
signal (5-6 kHz), which seemed to facilitate involvement of this diapason
signals in the defensive integration. The auditory EP generation thresholds
in the whole studied diapason were lower in the visually deprived nestlings
than in the normally developing one; however, the ability of the acoustic
signals to suppress alimentary reactions fell significantly.
Kind regards
Sonja Amoser
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University of Vienna, Dept. of Behavioural Biology
Sonja Amoser
PhD Student, Research Associate
Althanstrasse 14
1090 Vienna
Austria
tel: +43 (1) 4277 54467
fax: +43 (1) 4277 54506
mobile: +43 (664) 500 61 06
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