The Chimp Challenge: Working memory in chimps and humans

Matsuzawa (2012) presented work at Evolang demonstrating the working memory abilities of chimpanzees. (Inoue & Matsuzawa, 2007) found that chimpanzees can correctly remember the location of 9 randomly arranged numerals displayed for 210ms - shorter than an average human eye saccade. Humans, however, perform poorly at this task. Matsuzawa suggests a semantic link hypothesis: while chimps have good visual, eidetic memory, humans are good at symbolic associations. The extra information in the semantic, linguistic links that humans possess increase the load on working memory and make this task difficult for them. We were interested to see if a wider search could find humans that matched the performance of the chimpanzees. We created an online version of the experiment and challenged people to play. We also attempted to run a non-semantic version of the task to see if this made the task easier. We found that, while humans can perform better than Inoue and Matsuzawa (2007) suggest, chimpanzees can perform better still. We also found no evidence to support the semantic link hypothesis