Due in part to its complex nature, there is still much to uncover in the investigation of the neural processes that contribute to synchronization between speakers and listeners during communication in the context of social cognition, specifically between native and nonnative English speakers and listeners. This study used a novel method of hyperscan analysis and aimed to explore the effects of listening effort (LE) on brain-to-brain synchrony during communication, which is affected by various factors such as the listening environment, speech quality, hearing abilities, and linguistic complexity. The study analyzed brain-to-brain synchronization (B-bsync) patterns between speakers and listeners in situations where there is poor speech quality (accented English) or linguistic complexity (bilingual speakers) and its relationship to the corresponding number of hesitations/filler words in story recall of the listener. The study used a mixed-methods approach to investigate the impact of LE on brain-to-brain synchronization during communication in less-than-ideal conditions. The study found that there was significant synchronization between speakers and listeners in the native English to native English condition, with peak synchronization occurring at 0.5 and 1 second time shift, followed by a second peak at 5 seconds. In the native English speaker to nonnative English listener condition, significant speaker-to-listener coupling was observed at a time shift of 6 seconds, with listeners lagging the speaker. The synchronized brain regions were similar to those observed in the native speaker to native listener condition, but with two differences: there was no synchronization in the frontal eye fields, and there was synchronization in the left inferior frontal gyrus (LIFG), which is involved in syntactic processing. Results also showed that non-native accented speech required more cognitive resources for processing in bilinguals than in monolinguals, as evidenced by increased processing time and activation of additional brain regions (dorsolateral prefrontal cortex, middle temporal gyrus, inferior temporal gyrus, and Pars Triangularis). Overall, the study contributes to understanding communication complexities across language barriers and identifies differences in brain region activity responsible for language processing of foreign dialects and secondary language, conditions that are becoming increasingly common. The findings have implications for improving communication in diverse settings and highlight the importance of considering LE in communication research. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]