Marin-Garcia, E. 1, 2, 3 , Mattfeld, A. T. . 1 , Candon, K. C. 1 & Gabrieli, J. D. E. . 1
1 Massachusetts Institute of Technology
2 Basque Center on Cognition, Brain and Language
3 Ikerbasque
Retrieval practice compared to study alone increases memory performance, which is known as the testing effect. The neurobiological bases of the testing effect are not clear. In the present study participants were instructed to learn Swahili-English vocabulary word-pairs. During training outside of the scanner, participants were assigned randomly to the study group, which only studied the word-pairs, or to the test group, which both studied and tested the word-pairs. After a week delay, all participants returned for the same final cued-recall test in the scanner. The test group compared to the study group showed enhanced activation for correct > forget trials in left putamen and left supramarginal gyrus. This reflects an enriched representation of the items that facilitate its retrieval. These areas were functionally connected with right putamen and bilateral precentral gyrus, which are areas related with the onset of the verbal answer. In contrast, for the study group compared to the test group, activation was greater in regions throughout the frontal cortex for correct > forget trials. There was an increased functional connectivity of these areas with the bilateral inferior parietal lobe and middle frontal gyrus. The activity and connectivity of these regions are typically related to successful retrieval. These activity pattern differences between groups may be the base of the memory benefit associated with testing effect.