Eye movement performance and prefrontal hemodynamics during saccadic eye movements in the elderly.
No previous study has investigated age-related changes in prefrontal hemodynamics during saccade tasks in a large number of elderly adults. The purpose of this study was to evaluate prefrontal activity related to the performance of anti-saccade in the elderly using near-infrared spectroscopy (NIRS). Ninety-six elderly adults and 22 young adults performed pro- and anti-saccade tasks. Measures included reaction times of both saccades, error rate during anti-saccade, and concentration of oxyhemoglobin (Deltaoxy-Hb) in the prefrontal cortex during both saccades. Saccade performance, especially error rate, was significantly poorer in the elderly than the young. In the elderly, error rates were widely distributed from 5% to 100%. In about half (48%) of the elderly, error rates were distributed under the mean+3 standard deviations (48%) for the young, and Deltaoxy-Hb did not differ significantly from that in the young. Elderly subjects whose anti-saccade reaction time was over the regression line (of reaction time in anti-saccade to that in pro-saccade in the young)+2 standard errors showed a strong positive correlation (r=0.79) between Deltaoxy-Hb and error rate, as did those whose error rate exceeded 48%. In the elderly subjects whose error rates exceeded 90%, Deltaoxy-Hb was extremely small and deviated greatly from the correlation between Deltaoxy-Hb and error rate. Based on these findings, we propose a method of evaluating inhibitory function and attention allocation in anti-saccade performance, which is mainly related to the prefrontal cortex, in the elderly, using NIRS.
Fujiwara
Katsuo
K
Department of Human Movement and Health, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan. fujikatu@med.m.kanazawa-u.ac.jp
Kiyota
Naoe
N
Kunita
Kenji
K
Yasukawa
Midori
M
Maeda
Kaoru
K
Deng
Xingyun
X
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D005260:Female; D006439:Hemodynamics; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010108:Oxyhemoglobins / Q000378:metabolism; D010775:Photic Stimulation; D017397:Prefrontal Cortex / Q000098:blood supply*; D012438:Saccades / Q000502:physiology*; D019265:Spectroscopy, Near-Infrared / Q000379:methods
D010108:Oxyhemoglobins