Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Ocular accommodation and cognitive demand: An additional indicator besides pupil size and cardiovascular measures? | Journal of Negative Results in BioMedicine BioMed Central Research Ocular accommodation and cognitive demand An additional indicator besides pupil size and cardiovascular measures Stephanie Jainta Joerg Hoormannt and Wolfgang Jaschinskh Address Institut fuer Arbeitsphysiologie an der Universitaet Dortmund Ardeystrafie 67 D-44139 Dortmund Germany Email Stephanie Jainta - jainta@ Joerg Hoormann - hoormann@ Wolfgang Jaschinski - jaschinki@ Corresponding author tEqual contributors Open Access Published 23 August 2008 Received 18 April 2008 Journal of Negative Results in BioMedicine 2008 7 6 doi 1477-5751-7-6 Accepted 23 August 2008 This article is available from http content 7 1 6 2008 Jainta et al licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background The aim of the present study was to assess accommodation as a possible indicator of changes in the autonomic balance caused by altered cognitive demand. Accounting for accommodative responses from a human factors perspective may be motivated by the interest of designing virtual image displays or by establishing an autonomic indicator that allows for remote measurement at the human eye. Heart period pulse transit time and the pupillary response were considered as reference for possible closed-loop accommodative effects. Cognitive demand was varied by presenting monocularly numbers at a viewing distance of 5 D 20 cm which had to be read added or multiplied further letters were presented in a n-back task. Results Cardiovascular parameters and pupil size indicated a change in autonomic balance while error rates and reaction time confirmed the increased cognitive demand during task processing. An observed decrease in .
