Real-time use of spoken language is a fundamentally interactive process involving speech perception, speech production, linguistic competence, motor control, neurocognitive abilities such as working memory, attention, and executive function, environmental noise, conversational context, and--critically--the communicative interaction between speakers and listeners. In this thesis, use of a novel portable, real-time vocoder (PRTV) allowed for exploration of these foundational interactions in a variety of new ways. Experiment 1 linked perception and production, describing the impact of real-time perceptual transformation of acoustic feedback on segmental acoustic-phonetics in speech production. Chapter 2 obtained evidence for links between cognitive/attentional resources and real-time spoken language processing; in a series of three experiments, supra-segmental changes in speech production consistent with effects of limited attention were found as a result of real-time feedback perturbation. The playback experiment reported in Chapter 3 examined the impact of feedback-related changes in speech production from the point of view of a listener, finding that naive listeners could accurately discriminate differences in speech produced under unprocessed versus real-time perturbation conditions. While Chapters 1-3 focused on interactive effects in speech processing over short time periods, Chapter 4 investigated the coupling between speech perception and production in two subjects over 16 hours of PRTV use, exploring the impact of dynamic change on the perception/production relationship. Finally, the two experiments reported in Chapter 5 link the communicative context of real-world spoken language use to the domains and effectiveness of short-term perceptual learning. These findings enhance our understanding of several foundational linguistic and psychological issues, from basic links between perception and production to the experience of deaf users of cochlear implants. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]