Tamás Faragó

Eötvös Loránd University · Department of Ethology

Speech carries identity-diagnostic acoustic cues that help individuals recognize each other during vocal–social interactions. In humans, fundamental frequency, formant dispersion and harmonics-to-noise ratio serve as characteristics along which speakers can be reliably separated. The ability to infer a speaker’s identity is also adaptive for member...

Separation related disorder in dogs is a multi-faceted phenomenon. Dogs can react to the absence of their owner due to different inner states such as fear, panic or frustration. We hypothesized that dogs that are prone to frustration or fearfulness in other contexts would show a different behavioral response to separation from the owner. We investi...

Separation related problems (SRP) caused by distress associated with separation from the preferred member of the social group, can be characterised by their symptoms e.g., excessive vocalisation. In dogs’ separation whines, nonlinear phenomena (NLP) (abrupt changes in the resonance of the vocal folds) might occur, which could be adaptive in communi...

Dogs, similarly to infants, have been shown to be sensitive to human speech especially when it is directed to them. However, what essential acoustic, paralinguistic and lexical features of dog-directed speech are responsible for this preference in dogs is largely unknown. In the present study, generalized dog (DDS)-, infant (IDS)- and adult (ADS)-d...

During social interactions, acoustic parameters of tetrapods’ vocalisations reflect the emotional state of the caller. Higher levels of spectral noise and the occurrence of irregularities (non-linear phenomena NLP) might be negative arousal indicators in alarm calls, although less is known about other distress vocalisations. Family dogs experience...

Mental representations of one’s own body provide useful reference when negotiating physical environmental challenges. Body-awareness is a neuro-ontogenetic precursor for higher order self-representation, but there is a lack of an ecologically valid experimental approach to it among nonhuman species. We tested dogs (N = 32) in the ‘body as an obstac...

Dogs’ attachment towards humans might be the core of their social skillset, yet the origins of their ability to build such a bond are still unclear. Here we show that adult, hand-reared wolves, similarly to dogs, form individualized relationship with their handler. During separation from their handler, wolves, much like family dogs, showed signs of...

During separation, infants of various species often produce a special call type, the separation cry, which elicits instant response from the caregiver. Ignoring this stimulus might be costly; hence, adults have evolved a sensitivity to infant cries. As the acoustic structure and function of these vocalizations are conserved across mammals, adults m...

Dogs live in 45% of households, integrated into various human groups in various societies. This is certainly not true for wolves. We suggest that dogs' increased tractability (meant as individual dogs being easier to control, handle and direct by humans, in contrast to trainability defined as performance increase due to training) makes a crucial co...

Emotionally expressive non-verbal vocalizations can play a major role in human-robot interactions. Humans can assess the intensity and emotional valence of animal vocalizations based on simple acoustic features such as call length and fundamental frequency. These simple encoding rules are suggested to be general across terrestrial vertebrates. To t...

In the human speech signal, cues of speech sounds and voice identities are conflated, but they are processed separately in the human brain. The processing of speech sounds and voice identities is typically performed by non-primary auditory regions in humans and non-human primates. Additionally, these processes exhibit functional asymmetry in humans...

Dogs are looking at and gaining information from human faces in a variety of contexts. Next to behavioral studies investigating the topic, recent fMRI studies reported face sensitive brain areas in dogs' temporal cortex. However, these studies used whole heads as stimuli which contain both internal (eyes, nose, mouth) and external facial features (...

With very few exceptions, no coherent model of representing the self exists for nonhuman species. According to our hypothesis, understanding of the Self as an object’ can also be found in a wide range of animals including the dog, a fast-moving terrestrial predator/scavenger, with highly developed senses and complex cognitive capacity. We tested co...

When separated, young offsprings emit separation calls to draw their mother's attention, reduce distance between them, and recieve maternal care. Previous studies suggest that these calls arouse the caregiver's attention because of their special acoustic structure. Furthermore, under specific conditions separation calls evoke an approach response e...

Conspecific individual recognition using vocal cues has been shown in a wide range of species but there is no published evidence that dogs are able to recognize their owner based on his/her voice alone (interspecific individual recognition). In our test, dogs had to rely on vocal cues to find their hidden owner in a two-way choice task. From behind...

Dog barks represent a major source of noise pollution worldwide. However, the exact reasons why dog barks annoy people and why particular people show stronger reactions to dog barks than other noises, are poorly understood. In a sound playback study, we tested Hungarian participants (N= 153) from three age groups and three residential areas. Each p...

Companion cats often occupy the same anthropogenic niche as dogs in human families. Still, cat cognition remains an underrepresented research subject in ethology. Our goal was to examine whether two components that are crucial in dog-human communicative interactions (sensitivity to ostensive signals; gaze following) are also present in cats. In a t...

A special area of human-machine interaction, the expression of emotions gains importance with the continuous development of artificial agents such as social robots or interactive mobile applications. We developed a prototype version of an abstract emotion visualization agent to express five basic emotions and a neutral state. In contrast to well-kn...

There is growing evidence that dog-directed and infant-directed speech have similar acoustic characteristics, like high overall pitch, wide pitch range, and attention-getting devices. However, it is still unclear whether dog- and infant-directed speech have gender or context-dependent acoustic features. In the present study, we collected comparable...

Separation-related disorder (SRD) is one of the most common behavioral problems of companion dogs, causing inconvenience and stress for dog owners and others living close by, as well as being considered as a major contributor to poor animal welfare. Although excessive vocalization is considered as one of the typical symptoms of SRD, until now there...

Emotional contagion, a basic component of empathy defined as emotional state-matching between individuals, has previously been shown in dogs even upon solely hearing negative emotional sounds of humans or conspecifics. The current investigation further sheds light on this phenomenon by directly contrasting emotional sounds of both species (humans a...

Vocal expressions of emotions follow simple rules to encode the inner state of the caller into acoustic parameters, not just within species, but also in cross-species communication. Humans use these structural rules to attribute emotions to dog vocalizations, especially to barks, which match with their contexts. In contrast, humans were found to be...

The visual sense of dogs is in many aspects different than that of humans. Unfortunately, authors do not explicitly take into consideration dog-human differences in visual perception when designing their experiments. With an image manipulation program we altered stationary images, according to the present knowledge about dog-vision. Besides the eff...

Body size is an important feature that affects fighting ability; however, size-related parameters of agonistic vocalizations are difficult to manipulate because of anatomical constraints within the vocal production system. Rare examples of acoustic size modulation are due to specific features that enable the sender to steadily communicate exaggerat...

Excessive dog barking is among the leading sources of noise pollution worldwide; however, the reasons for the annoyance of barking to people remained uninvestigated. Our questions were: is the annoyance rating affected by the acoustic parameters of barks; does the attributed inner state of the dog and the nuisance caused by its barks correlate; doe...

During speech processing, human listeners can separately analyze lexical and intonational cues to arrive at a unified representation of communicative content. The evolution of this capacity can be best investigated by comparative studies. Using functional magnetic resonance imaging, we explored whether and how dog brains segregate and integrate lex...

Empathy covers a wide range of phenomena varying according to the degree of cognitive complexity involved; ranging from emotional contagion, defined as the sharing of others' emotional states, to sympathetic concern requiring animals to have an appraisal of the others' situation and showing concern-like behaviors. While most studies have investigat...

Supporting data. (XLSX)

A) Bird’s-eye view drawing of the recording room, B) Side view picture of the recording room. (DOCX)

Anova output of the best-fit models after reduction. For all models the only predictor that remained after reduction was the type of whine (familiar vs stranger). (DOCX)

Acoustic communication can play an important part in mother-young recognition in many mammals. This, however, has still only been investigated in a small range mainly of herd- or colony-living species. Here we report on the behavioral response of kittens of the domestic cat, a typically solitary carnivore, to playbacks of "greeting chirps" and "meo...

Family dogs successfully follow human-given cues in a two-object choice test. However, whether this ability has any roots in dog–dog visual communication, has been seldom investigated. We designed a test where a video-projected, life-sized dog 'demonstrator' provided directional cues for the subjects by turning its head toward one of the two plates...

Barking is perhaps the most characteristic form of vocalization in dogs; however, very little is known about its role in the intraspecific communication of this species. Besides the obvious need for ethological research, both in the field and in the laboratory, the possible information content of barks can also be explored by computerized acoustic...

It is essential for social robots to fit in the human society. In order to facilitate this process we propose to use the family dog’s social behaviour shown towards humans as an inspiration. In this study we explored dogs’ low level social monitoring in dog-human interactions and extracted individually consistent and context dependent behaviours in...

During the approximately 18–32 thousand years of domestication [1], dogs and humans have shared a similar social environment [2]. Dog and human vocalizations are thus familiar and relevant to both species [3], although they belong to evolutionarily distant taxa, as their lineages split approximately 90–100 million years ago [4]. In this first compa...

Humans excel at assessing conspecific emotional valence and intensity, based solely on non-verbal vocal bursts that are also common in other mammals. It is not known, however, whether human listeners rely on similar acoustic cues to assess emotional content in conspecific and heterospecific vocalizations, and which acoustical parameters affect thei...

Wolves have a remarkably complex social system: they breed, hunt and keep large territories cooperatively. To maintain such an elaborate system, a similarly complex and sophisticated communication system would also be expected. Based on this, studying the vocal communication of wolves and comparing it with other canids of different levels of social...

During autophagy, double-membrane autophagosomes deliver sequestered cytoplasmic content to late endosomes and lysosomes for degradation. The molecular mechanism of autophagosome maturation is still poorly characterized. The small GTPase Rab11 regulates endosomal traffic, and is thought to function at the level of recycling endosomes. Here we show...

Nonhuman animals often use specific signals to initiate playful interactions. There is evidence also for different forms of play-maintenance. Playful encounters include out-of-context and exaggerated behavioural sequences. Scientists have already collected knowledge about virtual size modification via acoustic signalling in particular animal specie...

The secure base and safe haven effects of the attachment figure are central features of the human attachment theory. Recently, conclusive evidence for human analogue attachment behaviours in dogs has been provided, however, the owner's security-providing role in danger has not been directly supported. We investigated the relationship between the be...

A number of species are considered to use functionally referential signals such as alarm calls or food-related vocalizations. However, this particular function of communicative interaction has not previously been found in canids. We provide the first experimental indication that domestic dogs, Canis familiaris, rely on context-dependent signals dur...

In this paper we propose the application of evolutionary principles in studying technological devices and processes. First we introduce the concepts of Darwinian evolution, which we use to draw an analogy with technology and show how human-made devices can be treated as evolving artificial agents. After explaining the methodology of reconstructing...