Dissociation between seeing and acting: insights from common marmosets (Callithrix jacchus)

Area of Science:

• Cognitive Science
• Primate Behavior
• Comparative Psychology

Background:

• Perception-based assessments often uncover earlier cognitive abilities than action-based methods.
• This discrepancy is known as 'knowledge dissociation' in developmental and comparative psychology.

Purpose of the Study:

• To investigate 'knowledge dissociation' in common marmoset monkeys (Callithrix jacchus).
• To compare performance in action-based versus perception-based tasks involving object permanence and physical intuition.

Main Methods:

• Utilized a tube task paradigm with 28 common marmosets.
• Assessed gravity bias and object localization in action-based experiments (Experiments 1-2).
• Evaluated performance in an action-free perception task observing falling objects (Experiments 3-4).

Main Results:

• Common marmosets exhibited a gravity bias in action-based search tasks.
• In perception-based tasks, marmosets showed an intuition for continuity and solidity constraints.
• Performance improved in the action-free context compared to action-based scenarios.

Conclusions:

• Common marmosets display knowledge dissociation, understanding physical principles perceptually but not behaviorally.
• Perception-based measures reveal earlier cognitive competencies in marmosets than action-based tasks.
• Findings contribute to understanding the development of physical reasoning in non-human primates.