Spike dynamics in primate lateral prefrontal cortex during working memory and decision-making: A fractal analysis

The lateral prefrontal cortex plays a key role in working memory and decision-making. Using multiunit spike recordings from macaque dorsolateral and ventrolateral prefrontal cortex during a match-to-sample task, we quantified the complexity of inter-spike intervals using Higuchi, Katz, and box-counting fractal dimensions. Our results indicate that fractal dimensions differentiate cognitive processes associated with working memory and decision-making, revealing significant differences in firing patterns across prefrontal regions during distinct time intervals, training phases, and tasks. Functional distinctions between dorsolateral and ventrolateral prefrontal cortex were strongest before training, reflecting preferential involvement in spatial and shape processing. Ultimately, the findings highlight the potential of fractal analysis as a biomarker for cognitive functions and demonstrate the impact of training on the functional dynamics of these brain regions. This study contributes to a deeper understanding of how the lateral prefrontal cortex process spatial and visual characteristics, paving the way for future research in cognitive neuroscience.