Antal Dóka

A comparative approach to dogs' (Canis familiaris) and human infants' comprehension of various forms of pointing gestures

We investigated whether dogs and 2-, and 3-year-old human infants living, in some respects, in very similar social environments are able to comprehend various forms of the human pointing gesture. In the first study, we looked at their ability to comprehend different arm pointing gestures (long cross-pointing, forward cross-pointing and elbow cross-pointing) to locate a hidden object. Three-year-olds successfully used all gestures as directional cues, while younger children and dogs could not understand the elbow cross-pointing. Dogs were also unsuccessful with the forward cross-pointing. In the second study, we used unfamiliar pointing gestures i.e. using a leg as indicator (pointing with leg, leg cross-pointing, pointing with knee). All subjects were successful with leg pointing gestures, but only older children were able to comprehend the pointing with knee. We suggest that 3-year-old children are able to rely on the direction of the index finger, and show the strongest ability to generalize to unfamiliar gestures. Although some capacity to generalize is also evident in younger children and dogs, especially the latter appear biased in the use of protruding body parts as directional signals.

Co-operative interactions between blind persons and their dogs

Abstract In two studies, we have investigated the co-operative behaviour between dogs and their owners. We supposed that co-operative behaviour is an inherited trait in dogs, and is a major contributing factor in the development of successful guide dog performance. According to our view, leading a blind person involves complex behaviour where success depends on the ability of the participants to synchronise their actions. In Study I, we observed both British and Hungarian blind owners taking a half-hour walk in their neighbourhood. In Study II, both guide dogs with their blind and pet dogs with their blind-folded owners had to master an obstacle course. Measuring the frequency of initiations of various actions during leading their owners, dogs did not keep the role of the initiator to themselves. However, both dogs and humans were found to initiate more often in some types of actions, for example, guide dogs initialised avoidance or stepping up more often than their owners. Further, the role of the initiator was kept only for short durations, longer sequences of initialising were rare. Despite many differences among groups studied, we observed some qualitative similarities in the co-operative behaviour of dogs. We assume that during domestication, dogs have been selected for the ability to change to-and-fro the role of the initiator that seems to be fundamental in this type of co-operation. In the case of leading the blind, information should not only be provided but also accepted by both parties in the course of the joint actions, therefore, the leadership (the role of the initiator) may vary form one action to the next.

Chapter 3 The Dog as a Model for Understanding Human Social Behavior

This chapter was originally published in the book Advances in The Study of Behavior, Vol. 39, published by Elsevier, and the attached copy is provided by Elsevier for the authors benefit and for the benefit of the authors institution, for non-commercial research and educational use including without limitation use in instruction at your institution, sending it to specific colleagues who know you, and providing a copy to your institution’s administrator.

Dogs discriminate between barks: The effect of context and identity of the caller

In the present study we explored whether dogs (Canis familiaris) are able to discriminate between conspecific barks emitted in different contexts recorded either from the same or different individuals. Playback experiments were conducted with dogs using barks as stimuli in a habituation-dishabituation paradigm. Barks were recorded in two contexts (stranger at the fence and when the dog was left alone) from different individuals. We found that dogs distinguished between barks emitted in these two contexts and were also able to discriminate between different individuals which were barking in the same context. These findings suggest that dog bark may carry context- and individual-specific information for the conspecifics.

Classification of dog barks: A machine learning approach

In this study we analyzed the possible context-specific and individual-specific features of dog barks using a new machine-learning algorithm. A pool containing more than 6,000 barks, which were recorded in six different communicative situations was used as the sound sample. The algorithm’s task was to learn which acoustic features of the barks, which were recorded in different contexts and from different individuals, could be distinguished from another. The program conducted this task by analyzing barks emitted in previously identified contexts by identified dogs. After the best feature set had been obtained (with which the highest identification rate was achieved), the efficiency of the algorithm was tested in a classification task in which unknown barks were analyzed. The recognition rates we found were highly above chance level: the algorithm could categorize the barks according to their recorded situation with an efficiency of 43% and with an efficiency of 52% of the barking individuals. These findings suggest that dog barks have context-specific and individual-specific acoustic features. In our opinion, this machine learning method may provide an efficient tool for analyzing acoustic data in various behavioral studies.

Opioid antagonism of electroschock-induced seizures

Abstract Morphine, β-endorphin and [D-Ala 2 , D-Leu 5 ] enkephalin administered intracerebroventricularly exterted a protective on electroconvulsive shock (ECS)-induced seizures in mice. This effect was reversed by intraperitoneal injections of naltrexone. The role of μ and δ receptors in ECS-induced convulsions is discussed.

An ethopharmacological analysis of morphine effects in fish (Macropodus Opercularis)

The behavioural effects of morphine on fish (Macropodus opercularis) were studied by an ethopharmacological analysis. For this purpose active and passive behavioural units were observed. The results show that morphine treatment had a stimulating effect. However, the treatment resulted not in a general enhancement of active behavioural units, but in a selective increase of some of them, such as swimming and erratic behaviour, or in stereotyped behaviours, such as circling. By contrast, high dosages of morphine resulted in a decrease of escape and of standing under the surface behaviours.

Effects of morphine in different strains of paradise fish (Macropodus opercularis L.): An ethopharmacological analysis

The behavioural effects of morphine on random bred Macropodus opercularis , five strains of this species of fish, and the closely related subspecies M. opercularis concolor , were assessed by an ethopharmacological analysis based on the study of different active and passive behavioural units. The results showed that morphine In general these findings stress out the importance of ethopharmacological studies for assessing qualitative behavioural differences which may be related to genetically-modulated neurobiological differences.