Neurocognitive performance is enhanced during short periods of microgravity-Part 2.

Previous studies showed a decrease in reaction time during the weightlessness phase of a parabolic flight. This effect was found to be stronger with increasing task complexity and was independent of previous experience of weightlessness as well as anti-nausea medication. Analysis of event related potentials showed a decreased amplitude of the N100-P200 complex in weightlessness but was not able to distinguish a possible effect of task complexity. The present study aimed to extend this previous work, by comparing behavioral (reaction time) and neurological (event related potentials analysis) performance to a simple (oddball) and a complex (mental arithmetic + oddball) task during weightlessness. 28 participants participated in two experiments. 11 participants performed a simple oddball experiment in the 1G and 0G phases of a parabolic flight. 17 participants were presented a complex arithmetic task in combination with an oddball task during the 1G and 0G phases of a parabolic flight. Reaction time as well as event related potentials (ERP) were assessed. Results revealed a reduced reaction time (p < .05) for the complex task during 0G. No gravity effects on reaction time were found for the simple task. In both experiments a reduction of typical ERP amplitudes was noticeable in weightlessness. It is assumed that the weightlessness induced fluid shift to the brain is positively affecting neuro-behavioral performance.