A Theoretical Framework for Human and Nonhuman Vocal Interaction

Abstract

Vocal communication is a critical feature of social interaction across species; however, the relation between such behavior in humans and nonhumans remains unclear. To enable comparative investigation of this topic, we review the literature pertinent to interactive language use and identify the superset of cognitive operations involved in generating communicative action. We posit these functions comprise three intersecting multistep pathways: (a) the Content Pathway, which selects the movements constituting a response; (b) the Timing Pathway, which temporally structures responses; and (c) the Affect Pathway, which modulates response parameters according to internal state. These processing streams form the basis of the Convergent Pathways for Interaction framework, which provides a conceptual model for investigating the cognitive and neural computations underlying vocal communication across species.

Keywords: animal vocalization; language; nonverbal communication; social interaction; speech.

Figure 1

Diagram of the Convergent Pathways for Interaction framework, which depicts the set of cognitive processes involved in interactive vocal behaviors. The sensory information generated by a vocal partner or the environment is processed in a Sensory Comprehension module, and the generation of motor action is modeled as discrete Motor Processing modules. Between the sensory and motor components of the framework are three parallel pathways that shape an organism’s response (i.e., the Timing, Content, and Affect Pathways). Each pathway is composed of multiple discrete processing modules, and links between modules are labeled with numbers to facilitate discussion within the text.

Figure 2

Using the Convergent Pathways for Interaction Framework to investigate vocal communication in nonhuman species. Behaviors across four organisms are highlighted: (a) house mouse, (b) zebra finch, (c) singing mouse, and (d) vervet monkey. An example sonogram depicting the vocal behavior of each species is shown at the top of each panel. Below the sonograms, the aspects of the framework we hypothesize to be recruited by each vocal behavior are highlighted. The audio data in panel a was collected by Gregg Castellucci and in panels b and c by Michael Long. The finch and singing mouse images were adapted from artwork created by Julia Kuhl. The vervet monkey image and sonogram in panel d were provided by Julia Fischer (German Primate Center). The framework shown below each sonogram is illustrated in greater detail in Figure 1.