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Auditory feedback modulates development of kitten vocalizations.

Hubka P, Konerding W, Kral A - Cell Tissue Res. (2014)

Bottom Line: The voiced isolation calls ('meow') were further analyzed.The fundamental frequency decreased with age in all groups, most likely due to maturation of the vocal apparatus.Auditory feedback thus affects the acoustic structure of vocalizations and their ontogenetic development.

View Article: PubMed Central - PubMed

Affiliation: Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinics, Cluster of Excellence 'Hearing4all', Hannover Medical School, Feodor-Lynen-Str. 35, 30175, Hannover, Germany.

ABSTRACT
Effects of hearing loss on vocal behavior are species-specific. To study the impact of auditory feedback on feline vocal behavior, vocalizations of normal-hearing, hearing-impaired (white) and congenitally deaf (white) cats were analyzed at around weaning age. Eleven animals were placed in a soundproof booth for 30 min at different ages, from the first to the beginning of the fourth postnatal month, every 2 weeks of life. In total, 13,874 vocalizations were analyzed using an automated procedure. Firstly, vocalizations were detected and segmented, with voiced and unvoiced vocalizations being differentiated. The voiced isolation calls ('meow') were further analyzed. These vocalizations showed developmental changes affecting several parameters in hearing controls, whereas the developmental sequence was delayed in congenitally deaf cats. In hearing-impaired and deaf animals, we observed differences both in vocal behavior (loudness and duration) and in the calls' acoustic structure (fundamental frequency and higher harmonics). The fundamental frequency decreased with age in all groups, most likely due to maturation of the vocal apparatus. In deaf cats, however, other aspects of the acoustic structure of the vocalizations did not fully mature. The harmonic ratio (i.e., frequency of first harmonic divided by fundamental frequency) was higher and more variable in deaf cats than in the other study groups. Auditory feedback thus affects the acoustic structure of vocalizations and their ontogenetic development. The study suggests that both the vocal apparatus and its neuronal motor control are subject to maturational processes, whereas the latter is additionally dependent on auditory feedback in cats.

No MeSH data available.


Related in: MedlinePlus

Example spectrograms of isolation and combined calls. a–c Isolation calls are characterized by a harmonic structure. b The louder calls cover the entire frequency range accessible for analysis. c The isolation calls can vary in duration and in total may reach 2 s. Quantification of isolation calls was performed for F0, F1, their ratio and the maximum F0. d–f Combined calls were excluded from analysis; usually they started as an unvoiced call and, after a certain (varying) time, changed into a voiced call. g–i: Non-linear phenomena were often found in the calls. g A biphonation is characterized by a temporal breakdown of the harmonic structure of the call. h Frequency jumps were frequent in isolation calls (see also (a–c)). i Subharmonics are characterized by occurrence of additional components in the harmonic structure. j–l Examples of vocalizations from a congenitally deaf cat
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Fig1: Example spectrograms of isolation and combined calls. a–c Isolation calls are characterized by a harmonic structure. b The louder calls cover the entire frequency range accessible for analysis. c The isolation calls can vary in duration and in total may reach 2 s. Quantification of isolation calls was performed for F0, F1, their ratio and the maximum F0. d–f Combined calls were excluded from analysis; usually they started as an unvoiced call and, after a certain (varying) time, changed into a voiced call. g–i: Non-linear phenomena were often found in the calls. g A biphonation is characterized by a temporal breakdown of the harmonic structure of the call. h Frequency jumps were frequent in isolation calls (see also (a–c)). i Subharmonics are characterized by occurrence of additional components in the harmonic structure. j–l Examples of vocalizations from a congenitally deaf cat

Mentions: Vocalizations were first automatically classified as voiced and unvoiced, as described above. In all animal groups, the vast majority of the vocalizations were voiced, whereas hearing-impaired animals showed significantly fewer voiced vocalizations than did the other two groups of animals (hearing: 89 ± 6 %; deaf: 86.6 ± 9.8 %; impaired 69.7 ± 24.5 %; two-tailed t test, hearing vs. deaf: p = 0.442; hearing vs. impaired: p = 0.0096; impaired vs. deaf: p = 0.0025). This relation was similar across all age groups. The voiced vocalizations were identified as isolation calls based on the overall acoustic structure (Fig. 1a). The lowest frequency of the spectrogram, called the fundamental frequency (F0), was near 1 kHz. The spectrogram was further characterized by harmonically related frequency components, whereas for quantification purposes the first harmonic frequency was used, here denoted F1 (Fig. 1a). The maximum energy was observed either at the first or the second harmonic-frequency component. The isolation calls showed high intra-individual variability (Fig. 1a–i). The variability of the calls was expressed in several features including call durations – see Fig. 1a-c – and differently steep frequency increases at the onset (and thus the time at which the maximum F0 was reached). The frequency range of isolation calls, if of sufficient loudness, covered the whole frequency range available for analysis (500–22,000 Hz for fs = 44.1 kHz) in all experimental groups (Fig. 1b). The isolation calls were characterized as having the greatest energy at F1 or F2 and call durations of a few hundred ms up to ∼2 s (Fig. 1).Fig. 1


Auditory feedback modulates development of kitten vocalizations.

Hubka P, Konerding W, Kral A - Cell Tissue Res. (2014)

Example spectrograms of isolation and combined calls. a–c Isolation calls are characterized by a harmonic structure. b The louder calls cover the entire frequency range accessible for analysis. c The isolation calls can vary in duration and in total may reach 2 s. Quantification of isolation calls was performed for F0, F1, their ratio and the maximum F0. d–f Combined calls were excluded from analysis; usually they started as an unvoiced call and, after a certain (varying) time, changed into a voiced call. g–i: Non-linear phenomena were often found in the calls. g A biphonation is characterized by a temporal breakdown of the harmonic structure of the call. h Frequency jumps were frequent in isolation calls (see also (a–c)). i Subharmonics are characterized by occurrence of additional components in the harmonic structure. j–l Examples of vocalizations from a congenitally deaf cat
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4487352&req=5

Fig1: Example spectrograms of isolation and combined calls. a–c Isolation calls are characterized by a harmonic structure. b The louder calls cover the entire frequency range accessible for analysis. c The isolation calls can vary in duration and in total may reach 2 s. Quantification of isolation calls was performed for F0, F1, their ratio and the maximum F0. d–f Combined calls were excluded from analysis; usually they started as an unvoiced call and, after a certain (varying) time, changed into a voiced call. g–i: Non-linear phenomena were often found in the calls. g A biphonation is characterized by a temporal breakdown of the harmonic structure of the call. h Frequency jumps were frequent in isolation calls (see also (a–c)). i Subharmonics are characterized by occurrence of additional components in the harmonic structure. j–l Examples of vocalizations from a congenitally deaf cat
Mentions: Vocalizations were first automatically classified as voiced and unvoiced, as described above. In all animal groups, the vast majority of the vocalizations were voiced, whereas hearing-impaired animals showed significantly fewer voiced vocalizations than did the other two groups of animals (hearing: 89 ± 6 %; deaf: 86.6 ± 9.8 %; impaired 69.7 ± 24.5 %; two-tailed t test, hearing vs. deaf: p = 0.442; hearing vs. impaired: p = 0.0096; impaired vs. deaf: p = 0.0025). This relation was similar across all age groups. The voiced vocalizations were identified as isolation calls based on the overall acoustic structure (Fig. 1a). The lowest frequency of the spectrogram, called the fundamental frequency (F0), was near 1 kHz. The spectrogram was further characterized by harmonically related frequency components, whereas for quantification purposes the first harmonic frequency was used, here denoted F1 (Fig. 1a). The maximum energy was observed either at the first or the second harmonic-frequency component. The isolation calls showed high intra-individual variability (Fig. 1a–i). The variability of the calls was expressed in several features including call durations – see Fig. 1a-c – and differently steep frequency increases at the onset (and thus the time at which the maximum F0 was reached). The frequency range of isolation calls, if of sufficient loudness, covered the whole frequency range available for analysis (500–22,000 Hz for fs = 44.1 kHz) in all experimental groups (Fig. 1b). The isolation calls were characterized as having the greatest energy at F1 or F2 and call durations of a few hundred ms up to ∼2 s (Fig. 1).Fig. 1

Bottom Line: The voiced isolation calls ('meow') were further analyzed.The fundamental frequency decreased with age in all groups, most likely due to maturation of the vocal apparatus.Auditory feedback thus affects the acoustic structure of vocalizations and their ontogenetic development.

View Article: PubMed Central - PubMed

Affiliation: Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinics, Cluster of Excellence 'Hearing4all', Hannover Medical School, Feodor-Lynen-Str. 35, 30175, Hannover, Germany.

ABSTRACT
Effects of hearing loss on vocal behavior are species-specific. To study the impact of auditory feedback on feline vocal behavior, vocalizations of normal-hearing, hearing-impaired (white) and congenitally deaf (white) cats were analyzed at around weaning age. Eleven animals were placed in a soundproof booth for 30 min at different ages, from the first to the beginning of the fourth postnatal month, every 2 weeks of life. In total, 13,874 vocalizations were analyzed using an automated procedure. Firstly, vocalizations were detected and segmented, with voiced and unvoiced vocalizations being differentiated. The voiced isolation calls ('meow') were further analyzed. These vocalizations showed developmental changes affecting several parameters in hearing controls, whereas the developmental sequence was delayed in congenitally deaf cats. In hearing-impaired and deaf animals, we observed differences both in vocal behavior (loudness and duration) and in the calls' acoustic structure (fundamental frequency and higher harmonics). The fundamental frequency decreased with age in all groups, most likely due to maturation of the vocal apparatus. In deaf cats, however, other aspects of the acoustic structure of the vocalizations did not fully mature. The harmonic ratio (i.e., frequency of first harmonic divided by fundamental frequency) was higher and more variable in deaf cats than in the other study groups. Auditory feedback thus affects the acoustic structure of vocalizations and their ontogenetic development. The study suggests that both the vocal apparatus and its neuronal motor control are subject to maturational processes, whereas the latter is additionally dependent on auditory feedback in cats.

No MeSH data available.


Related in: MedlinePlus