Effect of overheard conversations on bystander productivity

Overheard cell phone conversations are often perceived as particularly annoying or disruptive. The effect on bystander productivity from overheard cell phone conversations for younger and older adults was investigated for two cognitive tasks, mental arithmetic and proofreading. Performance (accuracy and speeded response) was compared in the presence of overheard cell phone conversations, overheard face-to-face conversation, and in quiet. Subjective ratings of mental workload were also obtained in each condition. In general, overheard cell phone and face-to-face conversations had very similar detrimental effects on performance and were associated with greater ratings of frustration in the arithmetic task. When balanced for number of conversational turns and overall number of words, overheard cell phone conversations do not have a greater effect on bystander productivity than overheard face-to-face conversations.