PFC Activity Pattern During Verbal WM Task in Healthy Male and Female Subjects: A NIRS Study

Near-infrared spectroscopy (NIRS), as a non-invasive optical imaging method, has been widely used in psychology research. Working memory (WM) is an extensively researched psychological concept related to the temporary storage and processing of information. Many neuropsychological studies demonstrate that several brain areas of prefrontal cortex (PFC) are engaged during verbal WM tasks. The gender-based differences in WM remains under dispute. To better understand the active module and gender differences in PFC activity patterns during verbal WM tasks, we investigated the blood oxygenation changes of the PFC in 15 healthy subjects using a homemade multichannel continuous-wave NIRS instrument, while performing a verbal n-back task. We employed traditional activation and novel connectivity analyses simultaneously. Males had a higher level of oxygenation activity and connectivity in PFC than females. Only the results of females revealed a leftward lateralization in the 2-back task.