Internal states and extrinsic factors both determine monkey vocal production

Internal states and extrinsic factors both determine monkey vocal production.

A key question for understanding speech evolution is whether or not the vocalizations of our closest living relatives-nonhuman primates-represent the precursors to speech. Some believe that primate vocalizations are not volitional but are instead inextricably linked to internal states like arousal and thus bear little resemblance to human speech. Others disagree and believe that since many prim...

LANGUAGE DEVELOPMENT. The developmental dynamics of marmoset monkey vocal production.

Human vocal development occurs through two parallel interactive processes that transform infant cries into more mature vocalizations, such as cooing sounds and babbling. First, natural categories of sounds change as the vocal apparatus matures. Second, parental vocal feedback sensitizes infants to certain features of those sounds, and the sounds are modified accordingly. Paradoxically, our clos...

The developmental dynamics of marmoset monkey vocal production

striatal function, and, therefore, they may participate in its dysfunction in brain disorders. Our results demonstrate the existence of functional astro-neuronal networks that comprise subpopulations of astrocytes, neurons, and synapses belonging to specific brain circuits, which may differentially control specific circuit activity through selective signaling between particular astrocytes and n...

Monkey vocal tracts are speech-ready

For four decades, the inability of nonhuman primates to produce human speech sounds has been claimed to stem from limitations in their vocal tract anatomy, a conclusion based on plaster casts made from the vocal tract of a monkey cadaver. We used x-ray videos to quantify vocal tract dynamics in living macaques during vocalization, facial displays, and feeding. We demonstrate that the macaque vo...

Regression Modeling of a Physiological Parameter Affected by Both Intrinsic and Extrinsic Factors