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1.
PLoS Biol ; 17(11): e3000476, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31721761

RESUMO

Learning of most motor skills is constrained in a species-specific manner. However, the proximate mechanisms underlying species-specific learned behaviors remain poorly understood. Songbirds acquire species-specific songs through learning, which is hypothesized to depend on species-specific patterns of gene expression in functionally specialized brain regions for vocal learning and production, called song nuclei. Here, we leveraged two closely related songbird species, zebra finch, owl finch, and their interspecific first-generation (F1) hybrids, to relate transcriptional regulatory divergence between species with the production of species-specific songs. We quantified genome-wide gene expression in both species and compared this with allele-specific expression in F1 hybrids to identify genes whose expression in song nuclei is regulated by species divergence in either cis- or trans-regulation. We found that divergence in transcriptional regulation altered the expression of approximately 10% of total transcribed genes and was linked to differential gene expression between the two species. Furthermore, trans-regulatory changes were more prevalent than cis-regulatory and were associated with synaptic formation and transmission in song nucleus RA, the avian analog of the mammalian laryngeal motor cortex. We identified brain-derived neurotrophic factor (BDNF) as an upstream mediator of trans-regulated genes in RA, with a significant correlation between individual variation in BDNF expression level and species-specific song phenotypes in F1 hybrids. This was supported by the fact that the pharmacological overactivation of BDNF receptors altered the expression of its trans-regulated genes in the RA, thus disrupting the learned song structures of adult zebra finch songs at the acoustic and sequence levels. These results demonstrate functional neurogenetic associations between divergence in region-specific transcriptional regulation and species-specific learned behaviors.


Assuntos
Tentilhões/genética , Fatores de Transcrição/fisiologia , Vocalização Animal/fisiologia , Animais , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Tentilhões/fisiologia , Regulação da Expressão Gênica/genética , Variação Genética/genética , Aprendizagem/fisiologia , Neurônios/metabolismo , Aves Canoras/genética , Aves Canoras/fisiologia , Especificidade da Espécie , Fatores de Transcrição/genética , Transcriptoma
2.
Nat Neurosci ; 22(12): 2040-2049, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31768056

RESUMO

Internal states shape stimulus responses and decision-making, but we lack methods to identify them. To address this gap, we developed an unsupervised method to identify internal states from behavioral data and applied it to a dynamic social interaction. During courtship, Drosophila melanogaster males pattern their songs using feedback cues from their partner. Our model uncovers three latent states underlying this behavior and is able to predict moment-to-moment variation in song-patterning decisions. These states correspond to different sensorimotor strategies, each of which is characterized by different mappings from feedback cues to song modes. We show that a pair of neurons previously thought to be command neurons for song production are sufficient to drive switching between states. Our results reveal how animals compose behavior from previously unidentified internal states, which is a necessary step for quantitative descriptions of animal behavior that link environmental cues, internal needs, neuronal activity and motor outputs.


Assuntos
Corte , Modelos Psicológicos , Neurônios/fisiologia , Animais , Sinais (Psicologia) , Drosophila melanogaster , Retroalimentação , Feminino , Masculino , Optogenética , Vocalização Animal/fisiologia
3.
Acta Neurobiol Exp (Wars) ; 79(3): 309-317, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31587023

RESUMO

We determined CA1 hippocampal field to be involved in self-exposure, a type of novelty­seeking behaviour that has also been associated with short 22 kHz and flat 50 kHz ultrasonic vocalizations (USV) in adult male Long-Evans rats. Rats were habituated for three days to a self-exposure cage with two nose-poke holes. On day four, the animals from the experimental group were allowed to turn the cage light off for 5 s with a nose­poke (test/self­exposure session), while rats from control-yoked group had changing light conditions coupled and identical to the experimental animals. The experimental rats performed more nose-pokes during self-exposure session than animals from the control group. This effect was accompanied by a higher density of c-Fos-positive nuclei in the hippocampal CA1. There were no significant group differences in c-Fos expression in other brain regions analysed. However, possible involvement of several other structures in self-exposure (i.e., CA3, the dentate gyrus, amygdala, prefrontal cortex, and nucleus accumbens) is also discussed, as their correlational activity, reflected by c-Fos immunoactivity, was observed in the experimental rats. During test sessions, there were more nose-pokes accompanied by short 22 kHz calls and 50 kHz calls performed by the rats of the experimental group than of the control group. The CA1 region has previously been associated with novelty; short 22 kHz USV and flat 50 kHz USV could be associated with self-exposure, also they appear to be emitted correlatively.


Assuntos
Comportamento Exploratório/fisiologia , Hipocampo/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Vocalização Animal/fisiologia , Tonsila do Cerebelo/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/metabolismo , Masculino , Núcleo Accumbens/metabolismo , Ratos Long-Evans
4.
Nat Commun ; 10(1): 4592, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31597928

RESUMO

Across vertebrates, progressive changes in vocal behavior during postnatal development are typically attributed solely to developing neural circuits. How the changing body influences vocal development remains unknown. Here we show that state changes in the contact vocalizations of infant marmoset monkeys, which transition from noisy, low frequency cries to tonal, higher pitched vocalizations in adults, are caused partially by laryngeal development. Combining analyses of natural vocalizations, motorized excised larynx experiments, tensile material tests and high-speed imaging, we show that vocal state transition occurs via a sound source switch from vocal folds to apical vocal membranes, producing louder vocalizations with higher efficiency. We show with an empirically based model of descending motor control how neural circuits could interact with changing laryngeal dynamics, leading to adaptive vocal development. Our results emphasize the importance of embodied approaches to vocal development, where exploiting biomechanical consequences of changing material properties can simplify motor control, reducing the computational load on the developing brain.


Assuntos
Callithrix/fisiologia , Laringe/fisiologia , Prega Vocal/fisiologia , Vocalização Animal/fisiologia , Algoritmos , Animais , Animais Recém-Nascidos , Callithrix/crescimento & desenvolvimento , Feminino , Laringe/crescimento & desenvolvimento , Masculino , Modelos Biológicos , Ruído , Som , Prega Vocal/crescimento & desenvolvimento
5.
PLoS Biol ; 17(10): e3000478, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31639139

RESUMO

Genetic data indicate differences in speciation rate across latitudes, but underlying causes have been difficult to assess because a critical phase of the speciation process is initiated in allopatry, in which, by definition, individuals from different taxa do not interact. We conducted song playback experiments between 109 related pairs of mostly allopatric bird species or subspecies in Amazonia and North America to compare the rate of evolution of male discrimination of songs. Relative to local controls, the number of flyovers and approach to the speaker were higher in Amazonia. We estimate that responses to songs of relatives are being lost about 6 times more slowly in Amazonia than in North America. The slow loss of response holds even after accounting for differences in song frequency and song length. Amazonian species with year-round territories are losing aggressive responses especially slowly. We suggest the presence of many species and extensive interspecific territoriality favors recognition of songs sung by sympatric heterospecifics, which results in a broader window of recognition and hence an ongoing response to novel similar songs. These aggressive responses should slow the establishment of sympatry between recently diverged forms. If male responses to novel allopatric taxa reflect female responses, then premating reproductive isolation is also evolving more slowly in Amazonia. The findings are consistent with previously demonstrated slower recent rates of expansion of sister taxa into sympatry, slower rates of evolution of traits important for premating isolation, and slower rates of speciation in general in Amazonia than in temperate North America.


Assuntos
Especiação Genética , Filogenia , Reprodução/genética , Aves Canoras/classificação , Vocalização Animal/fisiologia , Animais , Brasil , Canadá , Feminino , Masculino , Peru , Filogeografia , Aves Canoras/genética , Simpatria , Estados Unidos , Gravação em Vídeo
6.
PLoS Comput Biol ; 15(9): e1006698, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31557151

RESUMO

Although information theoretic approaches have been used extensively in the analysis of the neural code, they have yet to be used to describe how information is accumulated in time while sensory systems are categorizing dynamic sensory stimuli such as speech sounds or visual objects. Here, we present a novel method to estimate the cumulative information for stimuli or categories. We further define a time-varying categorical information index that, by comparing the information obtained for stimuli versus categories of these same stimuli, quantifies invariant neural representations. We use these methods to investigate the dynamic properties of avian cortical auditory neurons recorded in zebra finches that were listening to a large set of call stimuli sampled from the complete vocal repertoire of this species. We found that the time-varying rates carry 5 times more information than the mean firing rates even in the first 100 ms. We also found that cumulative information has slow time constants (100-600 ms) relative to the typical integration time of single neurons, reflecting the fact that the behaviorally informative features of auditory objects are time-varying sound patterns. When we correlated firing rates and information values, we found that average information correlates with average firing rate but that higher-rates found at the onset response yielded similar information values as the lower-rates found in the sustained response: the onset and sustained response of avian cortical auditory neurons provide similar levels of independent information about call identity and call-type. Finally, our information measures allowed us to rigorously define categorical neurons; these categorical neurons show a high degree of invariance for vocalizations within a call-type. Peak invariance is found around 150 ms after stimulus onset. Surprisingly, call-type invariant neurons were found in both primary and secondary avian auditory areas.


Assuntos
Córtex Auditivo , Modelos Neurológicos , Neurônios/fisiologia , Vocalização Animal/fisiologia , Estimulação Acústica , Animais , Córtex Auditivo/citologia , Córtex Auditivo/fisiologia , Biologia Computacional , Feminino , Tentilhões/fisiologia , Masculino
7.
BMC Genomics ; 20(1): 629, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375088

RESUMO

BACKGROUND: Vocal learning, the ability to learn to produce vocalizations through imitation, relies on specialized brain circuitry known in songbirds as the song system. While the connectivity and various physiological properties of this system have been characterized, the molecular genetic basis of neuronal excitability in song nuclei remains understudied. We have focused our efforts on examining voltage-gated ion channels to gain insight into electrophysiological and functional features of vocal nuclei. A previous investigation of potassium channel genes in zebra finches (Taeniopygia guttata) revealed evolutionary modifications unique to songbirds, as well as transcriptional specializations in the song system [Lovell PV, Carleton JB, Mello CV. BMC Genomics 14:470 2013]. Here, we expand this approach to sodium, calcium, and chloride channels along with their modulatory subunits using comparative genomics and gene expression analysis encompassing microarrays and in situ hybridization. RESULTS: We found 23 sodium, 38 calcium, and 33 chloride channel genes (HGNC-based classification) in the zebra finch genome, several of which were previously unannotated. We determined 15 genes are missing relative to mammals, including several genes (CLCAs, BEST2) linked to olfactory transduction. The majority of sodium and calcium but few chloride channels showed differential expression in the song system, among them SCN8A and CACNA1E in the direct motor pathway, and CACNG4 and RYR2 in the anterior forebrain pathway. In several cases, we noted a seemingly coordinated pattern across multiple nuclei (SCN1B, SCN3B, SCN4B, CACNB4) or sparse expression (SCN1A, CACNG5, CACNA1B). CONCLUSION: The gene families examined are highly conserved between avian and mammalian lineages. Several cases of differential expression likely support high-frequency and burst firing in specific song nuclei, whereas cases of sparse patterns of expression may contribute to the unique electrophysiological signatures of distinct cell populations. These observations lay the groundwork for manipulations to determine how ion channels contribute to the neuronal excitability properties of vocal learning systems.


Assuntos
Tentilhões/genética , Tentilhões/fisiologia , Genômica , Aprendizagem , Neurônios/citologia , Vocalização Animal/fisiologia , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/fisiologia , Canais Iônicos/genética , Família Multigênica/genética , Sintenia
8.
Nat Commun ; 10(1): 3636, 2019 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-31406118

RESUMO

Human speech possesses a rich hierarchical structure that allows for meaning to be altered by words spaced far apart in time. Conversely, the sequential structure of nonhuman communication is thought to follow non-hierarchical Markovian dynamics operating over only short distances. Here, we show that human speech and birdsong share a similar sequential structure indicative of both hierarchical and Markovian organization. We analyze the sequential dynamics of song from multiple songbird species and speech from multiple languages by modeling the information content of signals as a function of the sequential distance between vocal elements. Across short sequence-distances, an exponential decay dominates the information in speech and birdsong, consistent with underlying Markovian processes. At longer sequence-distances, the decay in information follows a power law, consistent with underlying hierarchical processes. Thus, the sequential organization of acoustic elements in two learned vocal communication signals (speech and birdsong) shows functionally equivalent dynamics, governed by similar processes.


Assuntos
Acústica , Tentilhões/fisiologia , Fala/fisiologia , Vocalização Animal/fisiologia , Animais , Humanos , Linguagem , Linguística
9.
Nat Neurosci ; 22(9): 1469-1476, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31406364

RESUMO

Vocal learners use early social experience to develop auditory skills specialized for communication. However, it is unknown where in the auditory pathway neural responses become selective for vocalizations or how the underlying encoding mechanisms change with experience. We used a vocal tutoring manipulation in two species of songbird to reveal that tuning for conspecific song arises within the primary auditory cortical circuit. Neurons in the deep region of primary auditory cortex responded more to conspecific songs than to other species' songs and more to species-typical spectrotemporal modulations, but neurons in the intermediate (thalamorecipient) region did not. Moreover, birds that learned song from another species exhibited parallel shifts in selectivity and tuning toward the tutor species' songs in the deep but not the intermediate region. Our results locate a region in the auditory processing hierarchy where an experience-dependent coding mechanism aligns auditory responses with the output of a learned vocal motor behavior.


Assuntos
Córtex Auditivo/fisiologia , Vias Auditivas/fisiologia , Aprendizagem/fisiologia , Vocalização Animal/fisiologia , Animais , Percepção Auditiva/fisiologia , Tentilhões/fisiologia , Neurônios/fisiologia
10.
PLoS Biol ; 17(8): e3000375, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31454343

RESUMO

Songbirds are renowned for their acoustically elaborate songs. However, it is unclear whether songbirds can cognitively control their vocal output. Here, we show that crows, songbirds of the corvid family, can be trained to exert control over their vocalizations. In a detection task, three male carrion crows rapidly learned to emit vocalizations in response to a visual cue with no inherent meaning (go trials) and to withhold vocalizations in response to another cue (catch trials). Two of these crows were then trained on a go/nogo task, with the cue colors reversed, in addition to being rewarded for withholding vocalizations to yet another cue (nogo trials). Vocalizations in response to the detection of the go cue were temporally precise and highly reliable in all three crows. Crows also quickly learned to withhold vocal output in nogo trials, showing that vocalizations were not produced by an anticipation of a food reward in correct trials. The results demonstrate that corvids can volitionally control the release and onset of their vocalizations, suggesting that songbird vocalizations are under cognitive control and can be decoupled from affective states.


Assuntos
Corvos/fisiologia , Vocalização Animal/fisiologia , Volição/fisiologia , Acústica , Animais , Cognição/fisiologia , Aprendizagem/fisiologia , Masculino , Neurônios/fisiologia , Aves Canoras/fisiologia
11.
Nat Commun ; 10(1): 3796, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31439849

RESUMO

Marmosets have attracted significant interest in the life sciences. Similarities with human brain anatomy and physiology, such as the granular frontal cortex, as well as the development of transgenic lines and potential for transferring rodent neuroscientific techniques to small primates make them a promising neurodegenerative and neuropsychiatric model system. However, whether marmosets can exhibit complex motor tasks in highly controlled experimental designs-one of the prerequisites for investigating higher-order control mechanisms underlying cognitive motor behavior-has not been demonstrated. We show that marmosets can be trained to perform vocal behavior in response to arbitrary visual cues in controlled operant conditioning tasks. Our results emphasize the marmoset as a suitable model to study complex motor behavior and the evolution of cognitive control underlying speech.


Assuntos
Encéfalo/fisiologia , Callithrix/fisiologia , Condicionamento Operante/fisiologia , Vocalização Animal/fisiologia , Animais , Cognição , Feminino , Masculino , Modelos Animais
12.
Behav Processes ; 166: 103901, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31276743

RESUMO

Tonic Immobility (TI) functions as anti-predator defense. Its duration depends on cues signaling predator proximity. One such cue includes alarm calls from conspecifics and non-conspecifics. This study aimed to determine the cue within alarm calls that controls TI duration. We induced TI in chicks (Gallus gallus) and found that their TI durations increased in the presence of adult conspecific alarm calls, non-conspecific alarm calls, and synthetic sounds made of white noise set to the repetition rate found in natural alarm calls. Moreover, chicks did not increase their TI durations when exposed to conspecific attraction calls, synthetic sounds made of white noise set to the repetition rate found in natural attraction calls, and derived sounds made of a natural alarm call lacking an internote interval. We then created: 1) sounds with white noise set to the internote interval found in natural alarm calls and the note duration found in natural attraction calls, and 2) sounds with white noise set to the internote interval found in natural attraction calls and the note duration found in natural alarm calls. Neither affected TI duration. We conclude that repetition rate acts as a salient cue that lengthens TI duration.


Assuntos
Comportamento Animal/fisiologia , Resposta de Imobilidade Tônica/fisiologia , Som , Vocalização Animal/fisiologia , Animais , Galinhas
13.
Nat Commun ; 10(1): 3372, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358755

RESUMO

Bats exhibit a diverse and complex vocabulary of social communication calls some of which are believed to be learned during development. This ability to produce learned, species-specific vocalizations - a rare trait in the animal kingdom - requires a high-degree of vocal plasticity. Bats live extremely long lives in highly complex and dynamic social environments, which suggests that they might also retain a high degree of vocal plasticity in adulthood, much as humans do. Here, we report persistent vocal plasticity in adult bats (Rousettus aegyptiacus) following exposure to broad-band, acoustic perturbation. Our results show that adult bats can not only modify distinct parameters of their vocalizations, but that these changes persist even after noise cessation - in some cases lasting several weeks or months. Combined, these findings underscore the potential importance of bats as a model organism for studies of vocal plasticity, including in adulthood.


Assuntos
Acústica , Quirópteros/fisiologia , Ecolocação/fisiologia , Ruído , Vocalização Animal/fisiologia , Animais , Quirópteros/classificação , Aprendizagem/fisiologia , Meio Social , Especificidade da Espécie
14.
PLoS One ; 14(7): e0219749, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31356642

RESUMO

Ultrasonic vocalizations (USVs) of laboratory rodents indicate animal emotional arousal and may serve as models of human disorders. We analysed spectrographically USV calls of pup and adult fat-tailed gerbils Pachyuromys duprasi during 420-s tests, including isolation, touch and handling. Based on combination of six different USV syllable contour shapes and six different note compositions, we classified 782 USV syllables of 24 pups aged 5-10 days to 18 types and 232 syllables of 7 adults to 24 types. Pups and adults shared 16 of these 26 USV types. Percentages of USV syllables with certain contour shapes differed between pups and adults. The contour shape and note composition significantly affected most acoustic variables of USV syllables in either pups or adults. The 1-note USV syllables were most common in either pups or adults. Pup USV syllables were overall longer and higher-frequency than adult ones, reminiscent of the USV ontogenetic pathway of bats and distinctive to rats and mice. We discuss that the USV syllable types of fat-tailed gerbils were generally similar in contour shapes and note compositions with USV syllable types of mice and rats, what means that software developed for automated classifying of mice ultrasound might be easily adapted or re-tuned to gerbil USV calls. However, using fat-tailed gerbils as model for biomedical research including control of USV vocalization is only possible since 6th day of pup life, because of the delayed emergence of USV calls in ontogeny of this species.


Assuntos
Envelhecimento/fisiologia , Gerbillinae/fisiologia , Ultrassom , Vocalização Animal/fisiologia , Acústica , Análise de Variância , Animais , Animais Recém-Nascidos , Feminino , Masculino
15.
Neuron ; 103(3): 459-472.e4, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31204083

RESUMO

Vocalizations are fundamental to mammalian communication, but the underlying neural circuits await detailed characterization. Here, we used an intersectional genetic method to label and manipulate neurons in the midbrain periaqueductal gray (PAG) that are transiently active in male mice when they produce ultrasonic courtship vocalizations (USVs). Genetic silencing of PAG-USV neurons rendered males unable to produce USVs and impaired their ability to attract females. Conversely, activating PAG-USV neurons selectively triggered USV production, even in the absence of any female cues. Optogenetic stimulation combined with axonal tracing indicates that PAG-USV neurons gate downstream vocal-patterning circuits. Indeed, activating PAG neurons that innervate the nucleus retroambiguus, but not those innervating the parabrachial nucleus, elicited USVs in both male and female mice. These experiments establish that a dedicated population of PAG neurons gives rise to a descending circuit necessary and sufficient for USV production while also demonstrating the communicative salience of male USVs. VIDEO ABSTRACT.


Assuntos
Corte , Rede Nervosa/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , Vocalização Animal/fisiologia , Animais , Sinais (Psicologia) , Vias Eferentes/fisiologia , Feminino , Genes Reporter , Vetores Genéticos/genética , Lentivirus/genética , Masculino , Camundongos , Neurônios/fisiologia , Neurotransmissores/metabolismo , Optogenética , Centro Respiratório/fisiologia
16.
Nat Commun ; 10(1): 2577, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189912

RESUMO

Many organisms coordinate rhythmic motor actions with those of a partner to generate cooperative social behavior such as duet singing. The neural mechanisms that enable rhythmic interindividual coordination of motor actions are unknown. Here we investigate the neural basis of vocal duetting behavior by using an approach that enables simultaneous recordings of individual vocalizations and multiunit vocal premotor activity in songbird pairs ranging freely in their natural habitat. We find that in the duet-initiating bird, the onset of the partner's contribution to the duet triggers a change in rhythm in the periodic neural discharges that are exclusively locked to the initiating bird's own vocalizations. The resulting interindividually synchronized neural activity pattern elicits vocalizations that perfectly alternate between partners in the ongoing song. We suggest that rhythmic cooperative behavior requires exact interindividual coordination of premotor neural activity, which might be achieved by integration of sensory information originating from the interacting partner.


Assuntos
Comportamento Animal/fisiologia , Comportamento Cooperativo , Córtex Motor/fisiologia , Aves Canoras/fisiologia , Vocalização Animal/fisiologia , Animais , Feminino , Aprendizagem , Masculino
17.
PLoS One ; 14(6): e0217977, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31170251

RESUMO

This study presents an integrative bioacoustics approach to discriminate eight species of odontocetes found on the outer continental shelf and slope of the western South Atlantic Ocean. Spinner, Atlantic spotted, rough-toothed, Risso's, bottlenose, short-beaked common dolphins, killer and long-finned pilot whales were visually confirmed during recordings with a 3-element omnidirectional hydrophone array. Spectral and time parameters of whistles and echolocation clicks were used in a discriminant function analysis and a classification tree model. As a first step, whistles and clicks were analysed separately; a further analysis consisted of both vocalisations jointly classified. All species showed species-specific properties in their vocalisations. Whistles had greater misclassification rates when compared to clicks. The correct classification was enhanced by the joint step, given the 5.8% error in the discriminant function analysis and a misclassification rate of 18.8% in the tree model. In addition, Receiver Operating Characteristic curves resulting from the tree algorithm analysis exhibited better model efficiency for all species in the joint classification. These findings on acoustical discrimination of such abundant and cosmopolitan species contribute to delphinid classification systems.


Assuntos
Acústica , Golfinhos/fisiologia , Vocalização Animal/fisiologia , Algoritmos , Animais , Oceano Atlântico , Análise Discriminante , Geografia , Análise Multivariada , Curva ROC , Espectrografia do Som , Especificidade da Espécie , Fatores de Tempo
18.
PLoS One ; 14(5): e0214640, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31042731

RESUMO

Screams are acoustically distinct, high-pitched and high-amplitude calls, produced by many social species. Despite a wide range of production contexts, screams are characterised by an acoustic structure that appears to serve in altering the behaviour of targeted receivers during agonistic encounters. In chimpanzees, this can be achieved by callers producing acoustic variants that correlate with their identity, social role, relationship with the targeted recipient, the composition of the audience and the nature of the event. Although vervet monkeys (Chlorocebus pygerythrus) have been studied for decades, not much is known about their agonistic screams. Here, we examined agonistic screams produced by wild vervet monkeys to investigate the degree to which caller identity, social role and conflict severity affected call structure. We found that screams were both individually distinctive and dependent of the agonistic events. In particular, victim screams were longer and higher-pitched than aggressor screams, while screams produced in severe conflicts (chases, physical contact) had higher entropy than those in mild conflicts. We discuss these findings in terms of their evolutionary significance and suggest that acoustic variation might serve to reduce the aggression level of opponents, while simultaneously attracting potential helpers.


Assuntos
Comportamento Agonístico/fisiologia , Vocalização Animal/fisiologia , Animais , Evolução Biológica , Feminino , Masculino , Variações Dependentes do Observador , Comportamento Social
19.
Acta Neurobiol Exp (Wars) ; 79(1): 1-12, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038481

RESUMO

This study examined low-frequency ultrasonic vocalizations (lUSVs) in rats during two types of sexual interactions; postejaculatory interval (PEI) and barrier - noncontact (NC) test. We report distinct classes of lUSVs that can be assigned to different emotional states; relaxation vs. frustration. Totally flat, 22-kHz calls (Class A), were observed during the relaxation state following ejaculation; characterized by immobilization or grooming during the PEI. On the other hand, two-three component lUSVs (Class B) that start at a higher frequency (45-kHz: flat, upward or short signal) and then shift to 35-23-kHz (mostly to 28-23-kHz), correspond as we assume, to arousal and frustration - active states associated with sniffing a hole or exploration during the NC test. We suggest that momentary, abrupt decreases of arousal during the frustration state correspond to Class B lUSVs. The detailed spectral analysis of the high-frequency component of two-component lUSVs is crucial for establishing the relationship between such lUSVs and the corresponding behavior and emotional states. Our studies indicate that while the two-component Class B 22-kHz lUSVs may relate to the frustration state, a single component, flat, Class A lUSV relates to the relaxation state. The results of these studies support a notion that rats emit distinct vocalization patterns, reflecting their emotional states.


Assuntos
Emoções/fisiologia , Caracteres Sexuais , Comportamento Sexual Animal/fisiologia , Ultrassom , Vocalização Animal/fisiologia , Animais , Comportamento Exploratório/fisiologia , Feminino , Asseio Animal/fisiologia , Resposta de Imobilidade Tônica/fisiologia , Masculino , Ratos , Ratos Long-Evans
20.
eNeuro ; 6(2)2019.
Artigo em Inglês | MEDLINE | ID: mdl-31068363

RESUMO

In male songbirds, the motivation to sing is largely regulated by testosterone (T) action in the medial preoptic area, whereas T acts on song control nuclei to modulate aspects of song quality. Stereotaxic implantation of T in the medial preoptic nucleus (POM) of castrated male canaries activates a high rate of singing activity, albeit with a longer latency than after systemic T treatment. Systemic T also increases the occurrence of male-like song in female canaries. We hypothesized that this effect is also mediated by T action in the POM. Females were stereotaxically implanted with either T or with 17ß-estradiol (E2) targeted at the POM and their singing activity was recorded daily during 2 h for 28 d until brains were collected for histological analyses. Following identification of implant localizations, three groups of subjects were constituted that had either T or E2 implanted in the POM or had an implant that had missed the POM (Out). T and E2 in POM significantly increased the number of songs produced and the percentage of time spent singing as compared with the Out group. The songs produced were in general of a short duration and of poor quality. This effect was not associated with an increase in HVC volume as observed in males, but T in POM enhanced neurogenesis in HVC, as reflected by an increased density of doublecortin-immunoreactive (DCX-ir) multipolar neurons. These data indicate that, in female canaries, T acting in the POM plays a significant role in hormone-induced increases in the motivation to sing.


Assuntos
Estradiol/fisiologia , Motivação/fisiologia , Neurogênese/fisiologia , Área Pré-Óptica/metabolismo , Telencéfalo/metabolismo , Testosterona/fisiologia , Vocalização Animal/fisiologia , Animais , Canários , Estradiol/farmacologia , Feminino , Motivação/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Área Pré-Óptica/efeitos dos fármacos , Telencéfalo/efeitos dos fármacos , Testosterona/farmacologia , Vocalização Animal/efeitos dos fármacos
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