Listed here, in reverse chronological order, are academic publications discussing joint speech in some detail. There are contributions to phonetics, movement science, social psychology, and neuroscience, along with several theoretical articles.

Von Zimmerman, Jorina and Richardson, Daniel C. (2017) Verbal Synchrony and Action Dynamics in Large GroupsFrontiers in Psychology, 7:2034. [Available online]

In a group task that can only be solved collectively, groups who chanted in synchrony before taking part performed better and scored better on tests of memory and sense of affilliation.

Jasmin, K. M., Mc Gettigan, C., Agnew, Z. K., Lavan, N., Josephs, O., Cummins, F., and Scott, S. K. (2016) Cohesion and joint speech: Right hemisphere contributions to synchronized vocal production.The Journal of Neuroscience, 36(17):4669–4680. [Available online]

Here we use fMRI to demonstrate that cortical activity is markedly different when speaking in real-time synchronoy with a live person, but not with a recording, even when the speaker does not know the difference themselves.

Cummins, F. (2014). Voice, (inter-)subjectivity, and real-time recurrent interaction. Frontiers in Psychology: Cognitive Science, 5(760) doi: 10.3389/fpsyg.2014.00760 [Available online]

Theoretical treatment of some of the remarkable features of joint speech. Argues that joint speech has contributed to the foundation of the shared human world.

Cummins, F. (2014). The remarkable unremarkableness of joint speech. In Proceedings of the 10th International Seminar on Speech Production, pages 73–77, Cologne, DE. [pdf]

Short paper arguing that the phonetic form of joint speech is relatively unremarkable, and that conventional approaches to the analysis and understanding of speech will miss that which is special about joint speech.

Cummins, F., Li, C., and Wang, B. (2013). Coupling among speakers during synchronous speaking in English and Mandarin. Journal of Phonetics. 41(6):432–441. [pdf]

Phonetic analysis of joint speech in English and Mandarin.

Cummins, F. (2013). Towards an enactive account of action: Speaking and joint speaking as exemplary domains. Adaptive Behavior, 13(3):178-186. [pdf]

Theoretical article arguing that a useful technical vocabulary for discussion of joint speech is to be found in the theory of enaction.

Cummins,F. (2012). Periodic and aperiodic synchronization in skilled action. Frontiers in Human Neuroscience: 5:170; doi:10.3389/fnhum.2011.00170. [open access journal]

Consideration of the challenges that joint speech throws up if we consider it as a special kind of synchronised movement.

Cummins, F. (2009). Rhythm as entrainment: The case of synchronous speech. Journal of Phonetics. 37(1):16-28 [pdf]

Phonetic study of synchronous speech. Examines the auditory information necessary to allow synchronisation.

Cummins, F. (2006). Measuring synchronization among speakers reading together. In Proc. ISCA Workshop on Experimental Linguistics, pages 105–108, Athens, GR. [pdf]

Technical article describing a method for measuring just how synchronous two utterances are.

Cummins, F. (2004). Synchronization among speakers reduces macroscopic temporal variability. 26th Annual Meeting of the Cognitive Science Society, pp. 304-309. [pdf]

Getting people to speak in synchrony turns out to be a great way to reduce some of the variability inherent in speech production. Useful for phoneticians.

Cummins,F. (2003). Practice and performance in speech produced synchronously. Journal of Phonetics, 31(2):139-148.

Early article looking at the remarkable facility that all speakers seem to have to speak in unison with another.

Cummins, F. (2002). On synchronous speech. Acoustic Research Letters Online 3(1), 7–11. [pdf]

The first publication on the topic of synchronous speech, which is joint speech produced in the lab for analysis.