Processing of different word list lengths during encoding and retrieval in Broca's area

Broca's area is a region of the brain involved in the processing of verbal information, including memory encoding and retrieval. This study examined differences in the neural correlates of encoding and retrieval in Broca's area using word lists of varying lengths. Differences in the encoding and retrieval processes were assessed using word lists of different lengths: short (2-29), medium (30-59), and long (60-225) Latvian language nouns. In total, 23 participants completed the memory task. Each participant performed memory tasks with two short lists, two medium lists, and one long list, with varying list lengths within each diapason. We considered the activity of the F3 and F7 to represent our region of interest. We compared time-frequency (TF) data from encoding and retrieval across list lengths. The results revealed significant differences in TF plots for encoding and for correct and incorrect retrieval of information up to a list length of 50 words. Further increases in list length indicated greater similarity in brain functional patterns. For correct stimulus recognition or rejection of a distractor, the observed differences in TF depended on list length, and these differences were more pronounced under correct stimulus recognition. Encoding and correct answers during retrieval also showed statistically significant differences from incorrect answers (misses or false alerts) at different list lengths. Spectral power changes exhibited a nonlinear shape during both encoding and retrieval. The possible mechanisms differed during encoding and correct recognition versus mistakes.