Abstract
Changes in behavioral state induced by locomotor activity dramatically impact behavioral performance and brain activity. This has been demonstrated in various species from invertebrates to nonhuman primates (Chiappe et al., 2010; Neill & Stryker, 2010). While there is similar evidence from humans (Bullock et al., 2015), the neural mechanisms mediating of the effect of physical activity on cognitive performance are less clear. Here, we investigated whether physical activity modulates visual working memory. Participants (n=6) completed a continuous response visual working memory task (e.g., Zhang & Luck, 2008; Wilken & Ma, 2004) while seated on a stationary bike in three activity conditions: rest (mean heart rate (HR)=74.4 bpm), low intensity cycling (mean HR=106.6 bpm), and high intensity cycling (mean HR=133.7 bpm). Participants viewed a brief display (100 ms) of colored squares; 900 ms after the display offset, one stimulus location was probed and participants indicated the color of the square presented at that location using a selector on a color wheel. An analysis of the absolute response error revealed that errors in the low intensity exercise condition (M(SEM) = 54.18° (3.61°)) were larger than those observed at rest (49.13° (4.74°); t(5) = 3.29, p = .021). Consistent with this analysis, a maximum likelihood estimate of a standard mixture model suggested that the increase in response error is due to a reduced probability in memory and increased resolution of encoded items for supra-capacity arrays during low intensity exercise (probability in memory (Pmem) = 0.22) compared to rest (Pmem = 0.34) and high intensity exercise (Pmem = 0.31). These results are consistent with the conclusion that exercise modulates visual working memory by reducing the likelihood that stimulus information is encoded thus presenting greater error in reported colors during exercise.
Meeting abstract presented at VSS 2016