Wait, I will look it up! And you see the other person grabbing for his or her cell phone. Lately, there has been a lot of buzz on the extended mind, in part because of the book by Annie Murphy Paul. This study by Siler et al. published in May, examines the effect of cell phones on our memory and on the perception of where we got our memories. The results of the different experiments are interesting:

The experiments herein examined item and source memory for material that was either initially searched for in memory or on a smartphone. From Experiments 1a and 1b, participants exhibited better memory for the answers retrieved via smartphone but poorer source memory for that information. Experiment 2 was conducted to clarify the recall finding and found evidence of no difference for question modality. This finding is interesting and suggests that, though there are no additional benefits to looking up information, there is also not a cost compared to initially trying to retrieve information on your own. This finding contrasts with the broad claims in the literature that retrieval of knowledge from one’s own memory is the best means of enhancing later memory for that information (e.g., Benjamin & Pashler, 2015). Perhaps a more direct test of these possible memory benefits would include an extremely passive condition, similar to restudy conditions in the testing effect literature.

Abstract of the study:

It is difficult to monitor whether information was originally retrieved internally, from our own memory, or externally, from another person or a device. We report two experiments that examined whether people were more likely to confuse prior access to information on a smartphone with accessing their own knowledge. Participants were experimentally assigned to either attempt to answer questions from memory or with a smartphone. One week later, we tested memory for the answers and source memory for the modality of the original attempt to retrieve the answer. Participants exhibited poorer source memory for answers retrieved from a smartphone than for answers they initially attempted to retrieve from memory. Experiment 2 demonstrated that memory for the information was equivalent across conditions. These results demonstrate that we are prone to confusing information retrieved from internal and external memory stores, and we have a cognitive bias to appropriate external knowledge as our own.