Evaluation of the effects of vestibular stimulation on cognitive performance E. ROSA1,2, R.R. BAPTISTA1,3, R.F. SARTORI3, L. DISIUTA1, L. MIÉRES1, T. MASSONI1, D. GREEN4, G. NEELY2, T. RUSSOMANO1,4 1 PUCRS, John Ernsting Aerospace Physiology Lab, MicroG, Porto Alegre, RS, Brazil 2 Department of Psychology, Cognitive Science Program, Umeå University, Umeå, Sweden 3 PUCRS, Physical Education School, Porto Alegre, RS, Brazil 4 Centre of Human Aerospace and Physiological Sciences, Faculty of Life Sciences & Medicine, KCL, UK INTRODUCTION & AIM The multisensory influences of spatial disorientation (SD) include concurrent interactions of the visual, proprioceptive and vestibular systems. The effects of disorientation may compromise higher order functioning in secondary tasks, since cognitive resources are engaged in establishing orientation and balance. Responses to cognitive tasks pre-, during and after rotation were examined. Figure 1. Schematic view of a volunteer performing the cognitive test during rotation in the Barany’s Chair METHODS 24 volunteers were tested in 4 rotation runs (2 clockwise, 2 anticlockwise) with a speed of 120º/sec (20rpm) in a Barany’s Chair. They performed randomized distinct spatial and verbal cognitive tasks in 5 phases per run: pre-rotation (PRE), acceleration (ACCEL), constant speed (CONST), deceleration (PRR - perceived reverse rotation) and post-rotation (POST) (Figure 1). Accuracy of responses, reaction time and cognitive throughput were used as being indicative of cognitive performance in each of the 5 phases of the 4 runs. ESTIMATED MARGINAL MEANS OF AcR ESTIMATED MARGINAL MEANS OF RT ESTIMATED MARGINAL MEANS OF CT Figure 2. The main effect in AcR in the task factor was not significant. Figure 3. Verbal RT was significantly greater than spatial RT in all conditions Figure 4. Spatial TS were significantly greater than verbal TS Cognitive throughput: 60.000 (millisenconds/minute) [RT * (1/AVE correct responses)] RESULTS No significant difference was found for accuracy of responses (AcR), response time (RT) and throughput scores (TS) for spatial and verbal cognitive tasks between clockwise or anticlockwise rotation. The main effect in accuracy in the task factor was not significant: F(1, 23) = .01; p = .751 (Figure 2). Verbal RT was significantly greater than spatial RT in all conditions (F(1, 23) = 36.8; p < .001). Employing the Bonferroni post-hoc test, no significant differences were found between the conditions (for all, p > .05) (Figure 3). Spatial TS were significantly greater than verbal TS (F(1, 23) = 50.846; p < .001). Employing the Bonferroni post-hoc test, no significant differences were found between the conditions (for all, p > .05) (Figure 4). Difference (±SE) from baseline condition (PRE) for the 4 subsequent phases CONCLUSION The data of this study suggests that the direction of rotation does not impact differently the performance of the cognitive tasks. This implies that the brain processes cognitive functions during clockwise and anticlockwise rotation in the same way. Throughput scores have shown no significant differences between conditions within the same task, indicative of no significant influence of rotation in the performance of both cognitive tasks. Since there was no significant interaction in the mean throughput scores in the task*condition, this result can be interpreted according to the nature of the task itself. Accuracy and response times of spatial tasks were not affected because they seem to have stronger influence due to conflicts involving visual illusions, as demonstrated prior. Figure 5. Difference in the spatial task was significant between PRE and CONST condition (t = 2.667, df = 23, p = .007. The difference in the verbal task was significant between PRE and POST condition only (t = 2.633, df = 23, p = .007). REFERENCES Bednarek, H., Truszczyński, O., & Wutke, K. (2013). Cognitive Determinants of Pilots’ Effectiveness Under a False Horizon Illusion. The International Journal of Aviation Psychology, 23(3), 267-287. Gibb, R., Ercoline, B., & Scharff, L. (2011). Spatial disorientation: decades of pilot fatalities. Aviation, Space, and Environmental Medicine, 82(7), 717-724. Gresty, M. A., Golding, J. F., Le, H., & Nightingale, K. (2008). Cognitive impairment by spatial disorientation. Aviation, Space, and Environmental Medicine, 79(2), 105-111. CONTACT: EDUARDO ROSA – UMEÅ UNIVERSITET edro0004@gapps.umu.se