Selective attention and heart rate responses to natural and urban environments

We tested the hypothesis that exposure to nature stimuli restores depleted voluntary attention capacity and affects selective attention. Before viewing a video of either a natural or an urban environment, 28 subjects first completed a proofreading task to induce mental load and then performed Posner's attention-orienting task. After viewing the video they performed the attention-orienting task a second time. Cardiac inter-beat interval (IBI) was measured continuously to index autonomic arousal. Before the video both groups reacted faster to validly versus invalidly cued targets in the attention-orienting task. After the video, the urban group was still faster on validly versus invalidly cued trials, but in the nature group this difference disappeared. During the video the nature group had a longer mean IBI (lower heart rate) measured as the difference from baseline than the urban group. The results suggest that reduced autonomic arousal during the video engendered less spatially selective attention in the nature group compared to the urban group. (C) 2002 Elsevier Science Ltd. All rights reserved.