Speech anxiety (SA) training may help subjects improve their skills on keeping audiences interested in the speech and on managing calm or restless audiences. Attention and lack of attention during speeches are displayed through several nonverbal cues. Such and other nonverbal behaviors can also spread throughout a group and engage whole audiences. The current study is an inquiry into the nonverbal markers of attention and lack of attention during lectures (e.g. note taking, eye gaze towards the speaker, conduct with electronic devices such as mobile phones or laptops). Additionally, the study tries to identify nonverbal behaviors that are diffused and their spatial and time diffusion characteristics. 37 university students at the Ilmenau University of Technology have been observed during a 40-minutes lecture. A quantitative content analysis is conducted to identify patterns of behaviors depicting attention and inattention. Afterwards a qualitative content analysis is carried out to identify contagious behaviors and their spreading characteristics. The findings are used to design virtual audiences (VA) whose members react to each other or display observable audience responses (OAR) and will be implemented into training scenarios for training university students against SA.