Poster D94, Monday, March 27, 8:00 – 10:00 am, Pacific Concourse
The role of DLPFC in statistical learning: Evidence from Bilateral Transcranial Magnetic Stimulation
Dezso Nemeth1,2, Geza Ambrus3, Karolina Janacsek1,2, Anna Triborn3, Gyula Kovacs3; 1Eötvös Loránd University, Budapest, Hungary, 2Hungarian Academy of Sciences, Budapest, Hungary, 3Friedrich Schiller University, Jena, Germany
Human learning depends on multiple cognitive systems related to dissociable brain structures. These systems interact not only in cooperative but sometimes competitive ways in optimizing performance. Previous studies showed that manipulations reducing the engagement of frontal lobe-mediated explicit, attentional processes can lead to improved performance in striatum-related procedural learning. The aim of the present study was to investigate the role of the prefrontal cortex (PFC) in implicit statistical learning and its consolidation and to explore the competitive relationship between implicit statistical learning and frontal lobe functions. Healthy, young adults (n=22) were trained on a probabilistic sequence learning task. 1 Hz transcranial magnetic stimulation (TMS) or sham stimulation of both the left and right dorsolateral PFC (DLPFC) was applied right before the learning session and 4x during the learning session in order to disrupt frontal lobe functions. To assess the lasting effects of TMS on learning and consolidation, statistical learning performance (expressed as the faster reaction times for sequences with high as compared to low probabilities) was tested ten minutes, two hours, and 24 hours later. We found lower level of learning in the bilateral DLPFC as compared to the sham stimulation group ten minutes after learning. However, the DLPFC stimulation group showed significantly better performance compared to the sham group after the 24-hour consolidation period. Our results support a dynamic antagonist relationship between the brain networks of automatic and controlled processes.
Topic Area: LONG-TERM MEMORY: Skill learning