Team communication facilitates team coordination strategies and situations, and how teammates perceive one another. In human-machine teams, these perceptions affect how people trust and anthropomorphize their machine counterparts, which in turn affects future team communication, forming a feedback loop. This thesis investigates how personifying and objectifying contents in human-machine team communication relate to team performance and perceptions in a simulated remotely piloted aircraft system task environment. A total of 46 participants grouped into teams of two were assigned unique roles and teamed with a synthetic pilot agent that in reality was a trained confederate following a script. Quantities of verbal personifications and objectifications were compared to questionnaire responses about participants’ perceived trust and anthropomorphism of the synthetic pilot, as well as team performance. It was hypothesized that verbal personifications would positively correlate with reflective trust, anthropomorphism, and team performance, and that verbal objectifications would negatively correlate with the same measures. It was also predicted that verbal personifications would decrease over time as human teammates interact more with the machine teammate, and that verbal objectifications would increase. Verbal personifications were not found to be correlated with trust and anthropomorphism outside of perceptions related to gender, albeit patterns of change in the navigator’s personifications coincided with a co-calibration of trust among the navigator and the photographer. Results supported the prediction that verbal objectifications are negatively correlated with trust and anthropomorphism of a teammate. Significant relationships between verbal personifications and objectifications and team performance were not found. This study provides support to the notion that people verbally personify machines to ease communication when necessary, and that the same processes that underlie tendencies to personify machines may be reciprocally related to those that influence team trust. Overall, this study provides evidence that personifying and objectifying language in human-machine team communication is a viable candidate for measuring the perceptions and states of teams, even in highly restricted communication environments.

The current work investigated the emergence of leader-follower roles during social motor coordination. Previous research has presumed a leader during coordination assumes a spatiotemporally advanced position (e.g., relative phase lead). While intuitive, this definition discounts what role-taking implies. Leading and following is defined as one person (or limb) having a larger influence on the motor state changes of another; the coupling is asymmetric. Three experiments demonstrated asymmetric coupling effects emerge when task or biomechanical asymmetries are imputed between actors. Participants coordinated in-phase (Ф =0o) swinging of handheld pendulums, which differed in their uncoupled eigenfrequencies (frequency detuning). Coupling effects were recovered through phase-amplitude modeling. Experiment 1 examined leader-follower coupling during a bidirectional task. Experiment 2 employed an additional coupling asymmetry by assigning an explicit leader and follower. Both experiment 1 and 2 demonstrated asymmetric coupling effects with increased detuning. In experiment 2, though, the explicit follower exhibited a phase lead in nearly all conditions. These results confirm that coupling direction was not determined strictly by relative phasing. A third experiment examined the question raised by the previous two, which is how could someone follow from ahead (i.e., phase lead in experiment 2). This was tested using a combination of frequency detuning and amplitude asymmetry requirements (e.g., 1:1 or 1:2 & 2:1). Results demonstrated larger amplitude movements drove the coupling towards the person with the smaller amplitude; small amplitude movements exhibited a phase lead, despite being a follower in coupling terms. These results suggest leader-follower coupling is a general property of social motor coordination. Predicting when such coupling effects occur is emphasized by the stability reducing effects of coordinating asymmetric components. Generally, the implication is role-taking is an emergent strategy of dividing up coordination stabilizing efforts unequally between actors (or limbs).