Cognitive flexibility as it emerges over development and evolution: The case of two navigational tasks in humans

Humans and other mammals share many cognitive traits including similar memory systems and spatial cognition. The following experiments made use of humans' detailed similarities with other mammals in navigation and spatial memory to elucidate which cognitive traits give rise to the commonalities in and distinctive flexibility for two navigational processes in human adults, spatial reorientation and conjunctive moving object search. Human adults performed these two tasks in a manner similar to but more flexible than adult rats. In contrast, young children showed the same limitations as adult rats, even, for the case of spatial reorientation, when they had coded the information that adults used but they couldn't use and could use it to solve other memory tasks. Further experiments tested older children in the same reorientation and movable object search tasks, and found that children's ability to produce phrases that specify how to succeed at the task, but not their comprehension of such phrases or their IQ, age, working memory capacity, or oriented conjunctive memory, correlated with adultlike success at the spatial memory tasks. Finally, a series of interference tasks run with adults suggested that language production capacities cause adultlike performance on both types of task by allowing the conjunction of types of information not used by the older capacities to solve the tasks. These experiments suggest that human adults' distinctive cognitive flexibility arises through language's access to more types of information than is used by phylogenetically older mechanisms for solving important tasks, permitting the efficient construction of novel representations.