Unique Cortical and Subcortical Activation Patterns for Different Conspecific Calls in Marmosets

Area of Science:

• Neuroscience
• Primate Communication
• Auditory Processing

Background:

• The common marmoset (Callithrix jacchus) exhibits a complex vocal repertoire.
• Previous studies show conspecific call processing activates fronto-temporal brain networks.
• Neural substrates differentiating marmoset vocalizations remain largely unexplored.

Purpose of the Study:

• To investigate the neural networks underlying the processing of distinct common marmoset vocalizations.
• To determine if different call types activate shared or unique brain pathways.
• To identify brain regions involved in discriminating between vocalizations.

Main Methods:

• Event-related functional magnetic resonance imaging (fMRI) at 9.4 Tesla was used.
• Nine adult marmosets were exposed to four distinct vocalizations: phee, chatter, trill, and twitter.
• A 3D convolutional neural network was employed to analyze brain activity patterns.

Main Results:

• Robust activation was observed in auditory cortices (core, belt, parabelt) and subcortical structures (inferior colliculus, medial geniculate nucleus, amygdala).
• Distinct neural activity patterns were identified for each vocalization type.
• The cerebellum and medial prefrontal cortex showed involvement in vocalization discrimination.

Conclusions:

• Common marmosets engage a shared neural network for processing vocalizations.
• Specific vocalizations elicit unique patterns of brain activation, indicating specialized processing.
• The findings contribute to understanding the neural basis of complex auditory perception and communication in primates.