Socio-affective behavior evaluation employing continuous real-time monitoring of ultrasonic vocalizations in freely moving rats in a semi-natural environment

Rats are very social creatures living in large social colonies in the wild. Some of their social features include maternal caregiving, juvenile play fighting, and even empathy-driven helping behavior. They also display vocal communicative signals called ultrasonic vocalizations (USV) that have been attributed to different behavioral connotations according to their characteristic differences. The evaluation of USV in rats makes them a great animal model for studying pathologies with impaired socio-affective behaviour, like autism spectrum disorder. Rodent models are in fact among the most employed methods for studying neuropsychiatric disorders and developing effective drug treatments. However, the lack of known molecular biomarkers for diagnosing neuropsychiatric disorders leads us to rely essentially on behavioral phenotypical readouts that sometimes may be subjective. Therefore it is crucial to apply robust and reproducible behavioural test paradigms developed with better and more standardized methodologies for improved translational research. In the doctoral dissertation project, I will first aim to establish and to validate a behavioral test paradigm for evaluating socio-affective behavior in rats living in a social colony in a semi-natural environment through continuous real-time monitoring of USV. An important aspect here will be to apply a method that allows to reliably identify the sender emitting USV in order to link their emission to the behavior displayed by the sender and potential recipients. Next, the established behavioral test paradigm will be applied in genetically-modified rat models with relevance to autism spectrum disorder. Finally, it will be combined with electrophysiological recording and/or stimulation in the brain. This dissertation project will provide a better understanding of socio-affective communication through USV in rodents and will help to develop better animal models for identifying novel and efficient therapeutic approaches for neuropsychiatric dysfunction.