title: Effects of oxygen concentration and flow rate on cognitive ability and physiological responses in the elderly.
abstract: The supply of highly concentrated oxygen positively affects cognitive processing in normal young adults. However, there have been few reports on changes in cognitive ability in elderly subjects following highly concentrated oxygen administration. This study investigated changes in cognitive ability, blood oxygen saturation (%), and heart rate (beats/min) in normal elderly subjects at three different levels of oxygen [21% (1 L/min), 93% (1 L/min), and 93% (5 L/min)] administered during a 1-back task. Eight elderly male (75.3 ± 4.3 years old) and 10 female (71.1 ± 3.9 years old) subjects, who were normal in cognitive ability as shown by a score of more than 24 points in the Mini-Mental State Examination-Korea, participated in the experiment. The experiment consisted of an adaptation phase after the start of oxygen administration (3 minutes), a control phase to obtain stable baseline measurements of heart rate and blood oxygen saturation before the task (2 minutes), and a task phase during which the 1-back task was performed (2 minutes). Three levels of oxygen were administered throughout the three phases (7 minutes). Blood oxygen saturation and heart rate were measured during each phase. Our results show that blood oxygen saturation increased, heart rate decreased, and response time in the 1-back task decreased as the concentration and amount of administered oxygen increased. This shows that administration of sufficient oxygen for optimal cognitive functioning increases blood oxygen saturation and decreases heart rate.
authors.affiliation: Department of Obstetrics & Gynecology, Konkuk University, Chungju 308-701, Republic of Korea.
authors.forename: Hyun-Jun
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, Seoul Clinical Laboratories, Seoul 140-809, Republic of Korea.
authors.forename: Hyun-Kyung
authors.initials: HK
authors.lastname: Park
authors.affiliation: Department of Information & Communication Engineering, Dongguk University, Seoul 100-715, Republic of Korea.
authors.forename: Dae-Woon
authors.initials: DW
authors.lastname: Lim
authors.affiliation: Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Biomedical & Health Science, Konkuk University, Chungju 380-701, Republic of Korea.
authors.forename: Mi-Hyun
authors.initials: MH
authors.lastname: Choi
authors.affiliation: Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Biomedical & Health Science, Konkuk University, Chungju 380-701, Republic of Korea.
authors.forename: Hyun-Joo
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Biomedical & Health Science, Konkuk University, Chungju 380-701, Republic of Korea.
authors.forename: In-Hwa
authors.initials: IH
authors.lastname: Lee
authors.affiliation: Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Biomedical & Health Science, Konkuk University, Chungju 380-701, Republic of Korea.
authors.forename: Hyung-Sik
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Biomedical & Health Science, Konkuk University, Chungju 380-701, Republic of Korea.
authors.forename: Jin-Seung
authors.initials: JS
authors.lastname: Choi
authors.affiliation: Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Biomedical & Health Science, Konkuk University, Chungju 380-701, Republic of Korea.
authors.forename: Gye-Rae
authors.initials: GR
authors.lastname: Tack
authors.affiliation: Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Biomedical & Health Science, Konkuk University, Chungju 380-701, Republic of Korea.
authors.forename: Soon-Cheol
authors.initials: SC
authors.lastname: Chung
keywords: 1-back task; blood oxygen saturation; clinical practice; cognitive ability; cognitive task; elderly; grant-supported paper; heart rate; highly concentrated oxygen; neural regeneration; neuroregeneration; physiological responses