Infant crying and the 'cry circuit' in marmoset monkeys
Friday, September 18, 2015 — Poster Session V
- JD Newman
When an infant human or other mammal becomes distressed, it produces vocalizations that we refer to as ‘crying.’ Cry sounds across a wide range of mammalian species share similar acoustic properties, and produce similar reactions on the part of the mother or other care-giver. The ubiquitous nature of this behavior suggests that it has had a long and conservative evolutionary history. It also suggests that the neural pathways underlying its production and appropriate response likewise are shared across mammals. Despite the importance of this behavior, little is known about the neural circuitry, hereafter the ‘cry circuit,’ underlying this behavior. In some mammals, cry sounds are produced throughout life, typically in adulthood when an individual becomes lost or separated from its social group. In the best-studied species, these ‘isolation calls’ are acoustically very similar, although less variable, to the sounds made in infancy. Some progress has been made to define the neural circuitry underlying cry sound production in the adults of several non-human primates. Here, I present current results from a study of the common marmoset monkey, Callithrix jacchus, in which Fos immunocytochemistry is used to identify neurons activated in the crying infant. Reactive cells can be found in the anterior cingulate gyrus and periventricular gray, structures already shown to be involved in isolation call production in adults. This study shows that brain areas important for production of calls in adult primates are functionally involved in producing the same vocalizations in infancy.