This thesis reports findings from a study (N = 60) of the impact of three communication modalities (voice only, text only, and voice and text simultaneously) on cognitive load, as measured by subjective reports of mental effort; on learning, as measured by tests of recall and retention; and on perceptions of presence as measured by a Presence Questionnaire (Witmer & Singer, 2005). Based on the results of prior empirical research, it is hypothesized that retention scores will be higher for voice participants and voice-and-text participants than for text-only participants; that cognitive load will be lower for voice participants and higher for text conditions; that voice will contribute to greater perceptions to presence; and that perceptions of presence will correlate with deeper learning. Study results indicate that communication modality significantly effected cognitive load (F (2, 54) = 4.58, p = 0.01) and retention (F (2, 54) = 3.53, p = 0.04), and that experience with and time spent in the virtual environment had significant effects on measures of cognitive load, retention, and presence: Significant between subjects effects were found for cognitive load and time (p = 0.23), for retention and time (p = 0.21), and for retention and experience (p = 0.03). [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.]