Multimodal Communication in the Human-Cat Relationship: A Pilot Study

Across all species, communication implies that an emitter sends signals to a receiver, through one or more channels. Cats can integrate visual and auditory signals sent by humans and modulate their behaviour according to the valence of the emotion perceived. However, the specific patterns and channels governing cat-to-human communication are poorly understood. This study addresses whether, in an extraspecific interaction, cats are sensitive to the communication channel used by their human interlocutor. We examined three types of interactions-vocal, visual, and bimodal-by coding video clips of 12 cats living in cat cafés. In a fourth (control) condition, the human interlocutor refrained from emitting any communication signal. We found that the modality of communication had a significant effect on the latency in the time taken for cats to approach the human experimenter. Cats interacted significantly faster to visual and bimodal communication compared to the "no communication" pattern, as well as to vocal communication. In addition, communication modality had a significant effect on tail-wagging behaviour. Cats displayed significantly more tail wagging when the experimenter engaged in no communication (control condition) compared to visual and bimodal communication modes, indicating that they were less comfortable in this control condition. Cats also displayed more tail wagging in response to vocal communication compared to the bimodal communication. Overall, our data suggest that cats display a marked preference for both visual and bimodal cues addressed by non-familiar humans compared to vocal cues only. Results arising from the present study may serve as a basis for practical recommendations to navigate the codes of human-cat interactions.

Discrimination of cat-directed speech from human-directed speech in a population of indoor companion cats (Felis catus)

In contemporary western cultures, most humans talk to their pet companions. Speech register addressed to companion animals shares common features with speech addressed to young children, which are distinct from the typical adult-directed speech (ADS). The way dogs respond to dog-directed speech (DDS) has raised scientists' interest. In contrast, much less is known about how cats perceive and respond to cat-directed speech (CDS). The primary aim of this study was to evaluate whether cats are more responsive to CDS than ADS. Secondarily, we seek to examine if the cats' responses to human vocal stimuli would differ when it was elicited by their owner or by a stranger. We performed playback experiments and tested a cohort of 16 companion cats in a habituation-dishabituation paradigm, which allows for the measurement of subjects' reactions without extensive training. Here, we report new findings that cats can discriminate speech specifically addressed to them from speech addressed to adult humans, when sentences are uttered by their owners. When hearing sentences uttered by strangers, cats did not appear to discriminate between ADS and CDS. These findings bring a new dimension to the consideration of human-cat relationship, as they imply the development of a particular communication into human-cat dyads, that relies upon experience. We discuss these new findings in the light of recent literature investigating cats' sociocognitive abilities and human-cat attachment. Our results highlight the importance of one-to-one relationships for cats, reinforcing recent literature regarding the ability for cats and humans to form strong bonds.

How's my kitty? Acoustic parameters of cat-directed speech in human-cat interactions

In Western cultures, humans tend to use a specific kind of speech when talking to their pets, characterised, from an acoustical point of view, by elevated pitch and greater pitch modulation. Pet-directed speech (PDS), which has been mainly studied in dogs, shares some acoustic features with infant-directed speech (IDS), used when talking to young children. The purpose of this study was to test the hypothesis that adult humans also modify characteristics of their voice when talking to a cat. We compared acoustic parameters of speech directed to cats (CDS) and speech directed to adult humans (ADS). In a first experiment, we compared ADS and CDS utterances of male and female participants, addressing cats through video recordings, under controlled laboratory conditions. Both men and women used a higher pitch (mean fundamental frequency, or mean F0) in CDS vs. ADS. The second experiment was conducted under conditions allowing direct cat-human interactions, in a cohort of women. Once again, mean F0 was significantly higher in CDS vs. ADS. Overall, these data confirm our hypothesis that humans change the way they speak when addressing a cat, mainly by increasing the pitch of their voice. Further research is needed to fully investigate specificities of this speech.

Association of Amine-Receptor DNA Sequence Variants with Associative Learning in the Honeybee

Octopamine- and dopamine-based neuromodulatory systems play a critical role in learning and learning-related behaviour in insects. To further our understanding of these systems and resulting phenotypes, we quantified DNA sequence variations at six loci coding octopamine-and dopamine-receptors and their association with aversive and appetitive learning traits in a population of honeybees. We identified 79 polymorphic sequence markers (mostly SNPs and a few insertions/deletions) located within or close to six candidate genes. Intriguingly, we found that levels of sequence variation in the protein-coding regions studied were low, indicating that sequence variation in the coding regions of receptor genes critical to learning and memory is strongly selected against. Non-coding and upstream regions of the same genes, however, were less conserved and sequence variations in these regions were weakly associated with between-individual differences in learning-related traits. While these associations do not directly imply a specific molecular mechanism, they suggest that the cross-talk between dopamine and octopamine signalling pathways may influence olfactory learning and memory in the honeybee.