The same type of visual working memory limitations in humans and monkeys

Area of Science:

• Cognitive Neuroscience
• Comparative Psychology

Background:

• Rhesus monkeys are a common animal model for human memory.
• Understanding visual working memory (VWM) in non-human primates is crucial for comparative studies.

Purpose of the Study:

• To investigate whether the principles governing VWM are conserved between humans and rhesus monkeys.
• To compare established VWM limitation models using identical experimental paradigms.

Main Methods:

• Humans and rhesus monkeys performed nearly identical change-localization tasks.
• Five distinct models of VWM limitations were formally compared: item-limit, noise-based, and hybrid models.
• Change magnitude was varied alongside set size to differentiate model fits.

Main Results:

• The variable-precision model, a noise-based approach, provided the best fit for both species' data.
• Adding an item limit did not improve the explanatory power of the variable-precision model.
• Quantitative performance differences existed between species, but the underlying VWM principles were conserved.

Conclusions:

• VWM exhibits evolutionary continuity across primate species.
• The rhesus monkey serves as a valid model for studying the neural basis of multi-item VWM.
• Noise-based models, specifically variable precision, are superior to item-limit models for explaining VWM limitations.