Personality and lateralization in common marmosets (Callithrix jacchus)

Area of Science:

• Primate behavior and cognition
• Neuroscience and behavioral genetics
• Comparative psychology

Background:

• Hemispheric specialization influences behavior and personality.
• Individual differences in personality and hand preference are well-documented.
• Common marmosets exhibit stable hand preferences, making them suitable for research.

Purpose of the Study:

• To investigate the relationship between personality traits and hand preference in common marmosets (Callithrix jacchus).
• To identify major personality factors in marmosets and their association with behavioral lateralization.
• To establish the common marmoset as a primate model for studying personality-lateralization links.

Main Methods:

• Behavioral data from 56 species-specific behaviors were collected across 10 lab tests and social observations.
• 16 adult marmosets were studied, with data aggregated into 13 personality traits.
• Exploratory Factor Analysis (EFA) and multiple regression were used to analyze personality factors and hand preference, controlling for sex and age.

Main Results:

• Common marmosets display stable and distinct personality profiles.
• A single significant personality factor, termed "Inquisitiveness," emerged, explaining 38% of the variance.
• Inquisitiveness, characterized by interest in novelty, significantly predicted the strength of hand preference.

Conclusions:

• The study confirms stable personality structures in common marmosets.
• "Inquisitiveness" is identified as a key personality trait linked to behavioral lateralization.
• Common marmosets serve as a robust model for exploring the interplay between personality and brain lateralization in primates.