Poster F42, Tuesday, March 28, 8:00 – 10:00 am, Pacific Concourse
Learning of Adjacent and Non-adjacent Regularities in a Visuo-Syllabic Sequential Learning Task Using Event-Related fMRI
Leyla Eghbalzad1, Joanne Deocampo1, Gretchen Smith1, Gerardo Valdez1, Sabrina Na1, Tricia King1, Christopher Conway1; 1Georgia State University
The ability to learn sequential dependencies from the environment is important for language acquisition and skill development. Recent studies suggest there may be separate cognitive processes involved in learning adjacent versus non-adjacent dependencies, but the underlying neural correlates accompanying such learning are under-specified. We developed a novel visuo-syllabic sequential learning task, in which printed nonsense syllables were presented sequentially on the screen, generated from an artificial grammar that dictated adjacent and non-adjacent dependencies. Following exposure to grammatical sequences, sixteen healthy adults (age M=22.5, 9 females) used a keyboard to reproduce novel grammatical as well as ungrammatical sequences containing violations of the adjacent or non-adjacent dependencies. We used fMRI with a 3T scanner to evaluate BOLD activity while participants performed a familiarity judgment task in the scanner. The imaging analyses revealed significant bilateral activation of middle frontal gyrus (Brodmann areas [BA] 9 & 10) and left lateralized activation of precuneus and lingual gyrus (BA 7 & 18) for the ungrammatical compared to grammatical sequence contrast. Furthermore, increased activation in BA 7 & 18 correlated with participants’ behavioral learning of adjacent dependencies (rs= .50, p<0.05) whereas activation in BAs 9 &10 correlated with Digit Span Backwards (rs= .58, p<0.05) and processing speed (rs= .51, p<0.05). Results suggest that learning of structured sequences involves posterior perceptual and frontal brain regions, with posterior regions associated with adjacent-item pattern learning and frontal regions associated with working memory and processing speed, likely required to learn non-adjacent dependencies.
Topic Area: EXECUTIVE PROCESSES: Other