CONCENTRATED OXYGEN

“Love is like oxygen, you get too much you get too high, not enough and you’re gonna die…” -Sweet

Since I like to have all of the human studies in one place (as though you hadn’t noticed that yet), I decided to collect all the human studies on one of my favorite nootropics of all time…concentrated oxygen.

Atmospheric oxygen is around 21% while concentrated oxygen is around 30% or above in the human studies.

It enhances mood, memory, reaction time, visuospatial memory, verbal performance, dual n-back scores, working memory, and brain energy levels (unfortunately it doesn’t seem to improve my jokes…damn).

That’s one h#$% of a list!

It’s been shown to work in the healthy, the elderly, the mentally disabled, and ADHD sufferers and at the dose I use it is extremely low risk.

I first learned about this amazing enhancement from this book: Advances in Natural Medicines, Nutraceuticals and Neurocognition

I bought this concentrator over 3 years ago on ebay (I can’t currently find it there) and I’ve loved it.

This Oxygen Concentrator has very similar specs to the one I have.

I leave the concentrator running and usually take 2 to 3 minute sips of concentrated oxygen every 10 to 20 minutes while I’m working at home.

It bumps my blood oxygen level up from 98% to 99% as measured by my pulse oximeter.

In fact, I’m currently using my concentrator right now as I write this post!

Lookk howe gud it maks mai speling.

It is one of the best cognitive enhancers out there and “stacks” extremely well with a vibration plate ime.

The vibration plate enhances microcirculation (R, R) in conjunction with the increased oxygen level from the concentrator.

It’s a pretty simple idea but it’s very effective.

It also combines quite nicely with mitochondrial enhancers (intranasal insulin, LLLT, PQQ, etc.)…which makes a lot of sense given the role of oxygen in the electron transport chain.

I’ll be writing more about that soon.

Enjoy reading the work of the real heroes!

Where To Buy

Oxygen Concentrator

Pulse Oximeter

Human Studies

http://www.ncbi.nlm.nih.gov/pubmed/22285726

Neurosci Lett. 2012 Mar 9;511(2):70-3. doi: 10.1016/j.neulet.2012.01.024. Epub 2012 Jan 21.

Changes of 2-back task performance and physiological signals in ADHD children due to transient increase in oxygen level.

Kim SP1, Choi MH, Kim JH, Yeon HW, Yoon HJ, Kim HS, Park JY, Yi JH, Tack GR, Chung SC.
Author information

Abstract
This study investigated the effect of 92% oxygen administration on 2-back task performance, blood oxygen saturation (SpO(2) [%]), and heart rate (HR [bpm]) of Attention Deficit Hyperactivity Disorder (ADHD) children. Subjects were thirteen boys (mean 12.9±1.3 years) who were diagnosed as ADHD and are under treatment, having no disease or abnormality in a respiratory system or a periphery vascular flow system. The experiment consisted of two runs: one was a 2-back task under normal air (21% oxygen) condition and the other under hyperoxic air (92% oxygen) condition. The experiment sequence in each run consisted of three phases, which included the Adaptation phase (1 min) after oxygen administration, the Control phase (2 min) that maintained a stable condition before the task, and the Task phase (2 min) that performed 2-back task. SpO(2) and HR were measured during each phase. The analysis of cognitive performance with 92% oxygen administration when compared to 21% oxygen revealed that the response time decreased. When 92% oxygen in the air was supplied, the blood oxygen saturation increased while the heart rate decreased compared to those under the 21% oxygen condition. The response time also decreased for the subjects with a high SpO(2) during the Task phase. This showed that due to sufficient oxygen supply necessary for cognitive processing, SpO(2) increased and heart rate decreased. Therefore, an increase in cognitive ability such as a decrease in response time was observed in a transient period for ADHD children.

http://www.ncbi.nlm.nih.gov/pubmed/19429029

Neurosci Lett. 2009 Apr 10;453(3):175-7. doi: 10.1016/j.neulet.2009.02.050. Epub 2009 Feb 27.

Changes in reaction time when using oxygen inhalation during simple visual matching tasks.

Chung SC1, Tack GR, Choi MH, Lee SJ, Choi JS, Yi JH, Lee B, Jun JH, Kim HJ, Park SJ.
Author information

Abstract
This study attempted to identify the effect of inhalation of highly concentrated oxygen on reaction time during simple visual matching tasks. Nine right-handed male graduate students (23.0+/-1.4 years) participated in the study. Two subsets of simple visual matching tasks with similar difficulties were developed. The experiment consisted of visual matching tasks performed under two conditions: normal air (22.1% oxygen) and hyperoxic air (43.2% oxygen). There was a significant decrease in reaction time in the presence of 43.2% oxygen compared with the 22.1% oxygen condition. This result supports the hypothesis that hyperoxic air increase oxygen saturation level in the blood, lead to more available oxygen to the brain, thus increase the ability of cognitive processing.

http://www.ncbi.nlm.nih.gov/pubmed/20080151

Neurosci Lett. 2010 Mar 3;471(2):70-3. doi: 10.1016/j.neulet.2010.01.013. Epub 2010 Jan 18.

Activation of the limbic system under 30% oxygen during a visuospatial task: an fMRI study.

Choi MH1, Lee SJ, Yang JW, Choi JS, Kim HS, Kim HJ, Min BC, Park SJ, Jun JH, Yi JH, Tack GR, Chung SC.
Author information

Abstract
The purpose of this study was to observe activation of the limbic system during the performance of visuospatial tasks under 21% O(2) or 30% O(2). Eight right-handed male college students were selected as subjects for this study. A visuospatial task was presented while brain images were scanned by a 3T fMRI system. The experiment consisted of the following two runs: a visuospatial task under normal air (21% O(2)) and a visuospatial task under hyperoxia (30% O(2)). The accuracy rate on the visuospatial task was enhanced during 30% O(2) compared to 21% O(2). The neural activation areas of the limbic system were similar in the cingulate gyrus, thalamus, limbic lobe and parahippocampal gyrus. Increased neural activation was observed in the cingulate gyrus and thalamus under 30% O(2) compared to 21% O(2). Under 30% O(2), the improvement in visuospatial task performance was related to an increase in neural activation of subcortical structures, such as the thalamus and cingulate gyrus, as well as the cerebral cortex.

https://www.ncbi.nlm.nih.gov/pubmed/22817401

Geriatr Gerontol Int. 2013 Apr;13(2):384-7. doi: 10.1111/j.1447-0594.2012.00911.x. Epub 2012 Jul 23.

Correlation between cognitive ability measured by response time of 1-back task and changes of SpO2 by supplying three different levels of oxygen in the elderly.

Choi MH1, Kim HJ, Kim JH, Kim HS, Choi JS, Yi JH, Tack GR, Chung YS, Son I, Chung SC.
Author information

Abstract

AIM:
This study investigated the correlation between response time of the 1-back task and changes of blood oxygen saturation (SpO2 ) by supplying three different levels of oxygen (21%, 1 L/min; 93%, 1 L/min; 93%, 5 L/min) in the elderly.

METHODS:
A total of 17 older adults (mean age 72.9 ± 4.7 years) participated in the experiment. A 1-back task was used as a cognitive task. The experiment consisted of three phases, which included the adaptation phase (3 min) after oxygen administration, the control phase (2 min) that maintained a stable condition before the task, and the task phase (2 min) where the 1-back task was carried out. SpO2 was measured during each phase.

RESULTS:
As concentration level and supply of oxygen increased, SpO2 increased and response time of the 1-back task decreased.

CONCLUSION:
Highly concentrated oxygen administration can increase SpO2 in the elderly and an increase in cognitive performance, such as a decrease in response time, can be observed.

https://www.ncbi.nlm.nih.gov/pubmed/25206597

Neural Regen Res. 2013 Jan 25;8(3):264-9. doi: 10.3969/j.issn.1673-5374.2013.03.009.

Effects of oxygen concentration and flow rate on cognitive ability and physiological responses in the elderly.

Kim HJ1, Park HK2, Lim DW3, Choi MH4, Kim HJ4, Lee IH4, Kim HS4, Choi JS4, Tack GR4, Chung SC4.
Author information

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.

https://www.ncbi.nlm.nih.gov/pubmed/18322865

Int J Neurosci. 2008 Apr;118(4):593-606. doi: 10.1080/00207450601067299.

Changes in memory performance, heart rate, and blood oxygen saturation due to 30% oxygen administration.

Chung SC1, Lim DW.
Author information

Abstract
This study investigated the effect of 30% oxygen administration on memory cognitive performance, blood oxygen saturation, and heart rate. Ten healthy male and female college students (male: 25.8+/-0.8 years, female: 24.2+/-1.9 years) participated in the study. The results of the memory performance analysis reveal that word recall rates were enhanced with 30% oxygen administration compared to 21% oxygen. When 30% oxygen was supplied, blood oxygen saturation was increased and heart rate was decreased compared to that with 21% oxygen administration. Significant positive correlations were found between changes in oxygen saturation and heart rate and memory performance. This result supports the hypothesis that 30% oxygen administration would lead to increases in memory performance.

http://www.ncbi.nlm.nih.gov/pubmed/17662686

Appl Ergon. 2008 Mar;39(2):166-70. Epub 2007 Jul 27.

Physiological mechanism underlying the improvement in visuospatial performance due to 30% oxygen inhalation.

Chung SC1, Lee B, Tack GR, Yi JH, Lee HW, Kwon JH, Choi MH, Eom JS, Sohn JH.
Author information

Abstract
This study investigated the effect of 30% oxygen inhalation on visuospatial cognitive performance, blood oxygen saturation, and heart rate. Six male (25.8(mean)+/-1.0(SD) years) and six female (23.8+/-1.9 years) college students participated in this experiment. Two psychological tests were developed to measure the performance level of visuospatial cognition. The experiment consisted of two runs: one was a visuospatial cognition task under normal air (21% oxygen) condition and the other under hyperoxic air (30% oxygen) condition. The experimental sequence in each run consisted of four phases, that were Rest1 (1min), Control (1min), Task (4min), and Rest2 (4min). Blood oxygen saturation and heart rate were measured throughout the course of four phases. The analysis of behavioral performance with 30% oxygen administration when compared to 21% oxygen revealed that the mean performance was improved. When supplied 30% oxygen in the air, the blood oxygen saturation was increased while the heart rate was decreased compared to those under 21% oxygen condition. We conclude that 30% oxygen inhalation enhanced visuospatial performance by the increased the oxygen saturation in the blood.

http://www.ncbi.nlm.nih.gov/pubmed/18569150

Int J Neurosci. 2008 Jul;118(7):905-16. doi: 10.1080/00207450701750455.

A study on the effects of 40% oxygen on addition task performance in three levels of difficulty and physiological signals.

Chung SC1, Lee HW, Choi MH, Tack GR, Lee B, Yi JH, Kim HJ, Lee BY.
Author information

Abstract
This study investigated the effect of 40% oxygen administration on addition task performance in three levels of difficulty and physiological signals, such as blood oxygen saturation and heart rate. The accuracy rates of the addition tasks were enhanced with 40% oxygen administration compared to 21% oxygen. As the difficulty level increased, the difference in the accuracy rate between 40% and 21% oxygen administration increased. When 40% concentration oxygen was supplied, blood oxygen saturation was increased and heart rate was decreased compared to that with 21% oxygen administration. A positive correlation was found between task performance and oxygen saturation level during the Task3 phase. This result suggests that 40% oxygen administration would lead to increases in addition task performance.

http://www.ncbi.nlm.nih.gov/pubmed/17395994

Physiol Meas. 2007 Apr;28(4):389-96. Epub 2007 Mar 7.

Effects of high concentration oxygen administration on n-back task performance and physiological signals.

Chung SC1, Kwon JH, Lee HW, Tack GR, Lee B, Yi JH, Lee SY.
Author information

Abstract
This study investigated the effect of 40% oxygen administration on n-back task performance, blood oxygen saturation and heart rate. Five male (25.8 +/- 1.3 years) and five female (23.0 +/- 1.0 years) college students were selected as the subjects for this study. The experiment consisted of two runs: one was an n-back task with normal air (21% oxygen) administered and the other was with hyperoxic air (40% oxygen) administered. The experimental sequence in each run consisted of Rest1 (1 min), 0-back task (1 min), 2-back task (2 min) and Rest2 (4 min). Blood oxygen saturation and heart rate were measured throughout the four phases. The results of the n-back behavioural analysis reveal that accuracy rates were enhanced with 40% oxygen administration compared to 21% oxygen. When 40% oxygen was supplied, blood oxygen saturation was increased and heart rate was decreased compared to that with 21% oxygen administration. It is suggested that 40% oxygen can stimulate brain activation by increasing actual blood oxygen concentration in the process of cognitive performance, and hyperoxia makes heart rate decrease. This result supports the hypothesis that 40% oxygen administration would lead to increases in n-back task performance.

https://www.ncbi.nlm.nih.gov/pubmed/25857667

J Physiol Anthropol. 2015 Feb 20;34:3. doi: 10.1186/s40101-015-0043-9.

Effects of 92% oxygen administration on cognitive performance and physiological changes of intellectually and developmentally disabled people.

Kim HS, Choi MH, Baek JH, Park SJ, Lee JC, Jeong UH, Kim SP, Kim HJ, Choi Y, Lim DW, Chung SC.

Abstract

BACKGROUND:
The present study addressed how 92% oxygen administration affects cognitive performance, blood oxygen saturation (SpO2), and heart rate (HR) of intellectually and developmentally disabled people.

METHODS:
Seven males (28.9 ± 1.8 years) and seven females (34.4 ± 8.3 years) with intellectual and developmental disabilities (disabled level 2.1 ± 0.5) completed an experiment consisting a 0-back task with normal air (21% oxygen) administered in one run and hyperoxic air (92% oxygen) administered in the other run. The experimental sequence in each run consisted of a 1-min adaptation phase, 2-min control phase, and 2-min 0-back task phase, where SpO2 and HR were gauged for each phase.

RESULTS:
The administration of 92% oxygen increased 0-back task performance of intellectually and developmentally disabled people, in association with increased SpO2 and decreased HR. Our results demonstrate that sufficient oxygen supply subserving cognitive functions, even as a short-term effect, could increase cognitive ability for the intellectually and developmentally disabled people.

CONCLUSIONS:
It is concluded that enriched oxygen can positively affect, at least in the short-term, the working memory of those with intellectual and developmental disability.

https://www.ncbi.nlm.nih.gov/pubmed/23648624

NeuroRehabilitation. 2013;32(3):687-92. doi: 10.3233/NRE-130892.

Changes in simple visual matching task performance and physiological signals in intellectually and developmentally disabled people due to administration of highly concentrated oxygen.

Kim HS1, Choi MH, Kim HJ, Yeon HW, Yoon HJ, Lee IH, Hong SP, Yu NR, Choi JS, Yi JH, Chung YS, Lim DW, Chung SC.
Author information

Abstract

BACKGROUND:
This study attempted to identify the effect of administration of highly concentrated oxygen on simple visual matching task performance, blood oxygen saturation [SpO2 (%)], and heart rate [HR (bpm)] of intellectually and developmentally disabled people.

METHODS:
Nineteen intellectually and developmentally disabled people (mean age 30.6 ± 5.7 years) participated in an experiment consisting of a simple visual matching task performed under 21% and 92% oxygen. SpO2 and HR were measured under both oxygen conditions.

RESULTS:
When 92% oxygen was supplied, the response time decreased, SpO2 increased, and HR decreased compared to the vales obtained using 21% oxygen. The response time decreased for subjects with a high SpO2 and HR during the simple visual matching task phase.

CONCLUSION:
This result supports the hypothesis that administration of highly concentrated oxygen can positively affect the cognitive performance of intellectually and developmentally disabled people.

https://www.ncbi.nlm.nih.gov/pubmed/17053947

Appl Psychophysiol Biofeedback. 2006 Dec;31(4):281-93.

Effect of 30% oxygen administration on verbal cognitive performance, blood oxygen saturation and heart rate.

Chung SC1, Iwaki S, Tack GR, Yi JH, You JH, Kwon JH.
Author information

Abstract
This study investigated the effect of 30% oxygen administration on verbal cognitive performance, blood oxygen saturation, and heart rate. Five male (24.6(+/-0.9) years) and five female (22.2(+/-1.9) years) college students were selected as the subjects for this study. Two psychological tests were developed to measure the performance level of verbal cognition. The experiment consisted of two runs: one was a verbal cognition task, with normal air (21% oxygen) administered and the other was with hyperoxic air (30% oxygen) administered. The experimental sequence in each run consisted of Rest 1 (1 min), Control (1 min), Task (4 min), and Rest 2 (4 min). Blood oxygen saturation and heart rate were measured throughout the four phases. The results of the verbal behavioural analysis reveal that accuracy rates were enhanced with 30% oxygen administration compared to 21% oxygen. When 30% oxygen was supplied, blood oxygen saturation was increased significantly compared to that with 21% oxygen administration, whereas heart rate showed no significant difference. Significant positive correlations were found between changes in oxygen saturation and cognitive performance. This result supports the hypothesis that 30% oxygen administration would lead to increases in verbal cognitive performance.

https://www.ncbi.nlm.nih.gov/pubmed/16678926

Int J Psychophysiol. 2006 Oct;62(1):103-8. Epub 2006 May 6.

The effect of transient increase in oxygen level on brain activation and verbal performance.

Chung SC1, Sohn JH, Lee B, Tack GR, Yi JH, You JH, Jun JH, Sparacio R.
Author information

Abstract
This study aimed to investigate the hypothesis that a transient increase in oxygen level administered to subjects increases the BOLD effect in brain regions associated with verbal cognitive functioning and enhances performance accuracy. A verbal task was presented while brain images were scanned by a 3T fMRI system. The accuracy rate on the verbal task was enhanced during 30% oxygen administration compared to 21% oxygen administration. The neural activations were observed at the occipital, parietal, temporal and frontal lobes, during both 21% and 30% oxygen administration. Increased brain activations were observed in the right middle frontal gyrus, right inferior frontal gyrus, right superior frontal gyrus, cingulate gyrus, left middle temporal gyrus, and left fusiform gyrus with 30% oxygen administration. These results suggest that a higher concentration of breathed oxygen increases saturation of blood oxygen in the brain, and facilitates verbal cognitive performance.

https://www.ncbi.nlm.nih.gov/pubmed/16393883

Int J Neurosci. 2006 Feb;116(2):177-89.

The effect of oxygen administration on visuospatial cognitive performance: time course data analysis of fMRI.

Chung SC1, Lee B, Tack GR, Yi JH, You JH, Son SH.
Author information

Abstract
This study investigated the effects of 30% oxygen administration on visuospatial cognitive ability using time course data analysis of fMRI. A visuospatial task was presented while brain images were scanned by a 3T MRI system. The results showed that there was an improvement in performance and also increased BOLD intensity in the parietal lobe in the higher oxygen condition. There was positive relation between behavior performance and BOLD intensity in the right parietal lobe. This result supports the conclusion that the increase in the cognitive processing ability due to highly concentrated oxygen can be explained by the increase in the BOLD intensity.

https://www.ncbi.nlm.nih.gov/pubmed/15929498

Integr Physiol Behav Sci. 2004 Jul-Sep;39(3):153-65.

The effect of highly concentrated oxygen administration on cerebral activation levels and lateralization in visuospatial tasks.

Chung SC1, Tack GR, Kim IH, Lee SY, Sohn JH.
Author information

Abstract
This study investigated what effect a 30% oxygen administration had on visuospatial cognitive performance and cerebral activation and lateralization using fMRI. Eight college students were selected as the subjects for this study. An oxygen dispenser that provided 21% and 30% oxygen at a constant rate of 8L/min was developed. In order to measure the performance level of visuospatial cognition, two psychological tests were also developed. The experiment consisted of two runs, one for a visuospatial cognition task with normal air (21% oxygen) and the other for a visuospatial cognition task with hyperoxic air (30% oxygen). Functional brain images were taken with a 3T MRI using the single-shot EPI method. The results of the visuospatial behavioral analysis reveal that accuracy rates were enhanced with 30% oxygen administration when compared to 21% oxygen. There were more activations observed at the bilateral occipital, parietal, and frontal lobes with 30% oxygen administration. However, decreased cerebrum lateralization was observed with 30% oxygen administration in the same regions compared with 21% oxygen administration. Thus, it is concluded that the positive effect on the visuospatial cognitive performance level by the highly concentrated oxygen administration resulted from an increase of cerebrum activation and a decrease of cerebrum lateralization.

https://www.ncbi.nlm.nih.gov/pubmed/15684544

J Physiol Anthropol Appl Human Sci. 2005 Jan;24(1):51-3.

30% oxygen inhalation enhances cognitive performance through robust activation in the brain.

Sohn JH1, Chung SC, Jang EH.
Author information

Abstract
This study aimed to investigate whether inhalation of the air with 30% oxygen compared with normal air enhances cognitive functioning through increased activation in the brain. The verbal and visuospatial tasks were performed while brain images were scanned. The results showed that there were improvements in performance and also increased activation in several brain areas under the condition of 30% oxygen. These results suggest that a higher concentration of the inhaled oxygen increases the saturation of the blood oxygen in the brain, and facilitates cognitive performance.

https://www.ncbi.nlm.nih.gov/pubmed/15522765

Brain Cogn. 2004 Dec;56(3):279-85.

The effect of 30% oxygen on visuospatial performance and brain activation: an fMRI study.

Chung SC1, Tack GR, Lee B, Eom GM, Lee SY, Sohn JH.
Author information

Abstract
This study aimed to investigate the hypothesis that administration of the air with 30% oxygen compared with normal air (21% oxygen) enhances cognitive functioning through increased activation in the brain. A visuospatial task was presented while brain images were scanned by a 3 T fMRI system. The results showed that there was an improvement in performance and also increased activation in several brain areas in the higher oxygen condition. These results suggest that a higher concentration of breathed oxygen increases saturation of blood oxygen in the brain and facilitates performance.

https://www.ncbi.nlm.nih.gov/pubmed/10604851

Physiol Behav. 1999 Nov;67(5):783-9.

Cognitive performance, hyperoxia, and heart rate following oxygen administration in healthy young adults.

Scholey AB1, Moss MC, Neave N, Wesnes K.
Author information

Abstract
It was recently established that supplemental oxygen administration significantly enhances memory formation in healthy young adults. In the present study, a double-blind, placebo-controled design was employed to assess the cognitive and physiological effects of subjects’ inspiration of oxygen or air (control) prior to undergoing simple memory and reaction-time tasks. Arterial blood oxygen saturation and heart rate were monitored during each of six phases of the experiment, corresponding to baseline, gas inhalation, word presentation, reaction time, distractor and word recall, respectively. The results confirm that oxygen administration significantly enhances cognitive performance above that seen in the air inhalation condition. Subjects who received oxygen recalled more words and had faster reaction times. Moreover, compared to participants who inhaled air, they exhibited significant hyperoxia during gas administration, word presentation, and the reaction-time task, but not at other phases of the experiment. Compared to baseline, heart rate was significantly elevated during the word presentation, reaction-time, and distractor tasks in both the air and oxygen groups. In the oxygen group, significant correlations were found between changes in oxygen saturation and cognitive performance. In the air group, greater changes in heart rate were associated with more improved cognitive performance. These results are discussed in the context of cognitive demand and metabolic supply. It is suggested that under periods of cognitive demand a number of physiological responses are brought into play that serve to increase the delivery of metabolic substrates to active neural tissue. These mechanisms can be supplemented by increased availability of circulating blood oxygen, resulting in an augmentation of cognitive performance. Heart rate reactivity and the capacity for increased blood oxygen appear to be important physiological individual differences mediating these phenomena.

https://www.ncbi.nlm.nih.gov/pubmed/9694523

Psychopharmacology (Berl). 1998 Jul;138(1):27-33.

Oxygen administration selectively enhances cognitive performance in healthy young adults: a placebo-controlled double-blind crossover study.

Moss MC1, Scholey AB, Wesnes K.
Author information

Abstract
It was recently demonstrated that oxygen administration can improve performance on a simple word recall task in healthy young adults. This study was aimed at determining the impact of various durations of oxygen administration on a wider range of cognitive measures. This was achieved using the Cognitive Drug Research computerised test battery, and employing a double-blind, placebo-controlled crossover design. Over a period of 7 weeks, 20 participants were trained and subsequently assessed on the test battery under several durations of oxygen inhalation; air administered in an identical fashion served as a control. The results provided support for our earlier work in that increases were found in both immediate and delayed word recall. In addition, oxygen administration significantly improved performance on several measures of attention and vigilance. Simple reaction time, choice reaction time, digit vigilance reaction time and picture recognition reaction time were improved in a manner which depended on the duration of oxygen inspired. With the exception of word recall, no significant improvements were found for any measure of accuracy, nor were word recognition, digit memory scanning, or spatial memory improved. These results are discussed in the context of stages of information processing and are consistent with the hypothesis that cognitive performance is “fuel-limited” and can be differentially augmented by increasing the availability of the brain’s metabolic resources.

https://www.ncbi.nlm.nih.gov/pubmed/9862412

Psychopharmacology (Berl). 1998 Nov;140(1):123-6.

Oxygen and cognitive performance: the temporal relationship between hyperoxia and enhanced memory.

Scholey AB1, Moss MC, Wesnes K.
Author information

Abstract
Oxygen administration coinciding with word presentation enhances word recall in humans, suggesting that elevated levels of circulating blood oxygen may be available to neural memory consolidation processes. This double-blind experiment examined the relationship between blood oxygen levels and cognitive performance when oxygen was inspired for 2 min at different times relative to a simple word recall task, forward digit span and backward digit span. Transient hyperoxia, measured by haemoglobin-bound oxygen, was evident following oxygen inspiration. Neither forward nor backward digit span was affected by oxygen administration. Word recall (12 min following word presentation) was enhanced when oxygen was administered 5 min prior to, immediately before or immediately following word presentation; but not 10 min prior to, 5 min following nor 10 min following, word presentation. These data suggest that oxygen administration can selectively enhance aspects of cognitive performance and support a hypothesis whereby supplemental blood oxygen is sequestered by neural mechanisms involved in memory consolidation.

https://www.ncbi.nlm.nih.gov/pubmed/9600580

Psychopharmacology (Berl). 1998 Apr;136(4):349-56.

Fuels for memory: the role of oxygen and glucose in memory enhancement.

Winder R, Borrill J.

Abstract
Recent studies indicate that some aspects of memory can be enhanced by the administration of oxygen or glucose. Considering the dependency of glucose metabolism upon oxygen supply, the present study predicted that administering a combination of 100% oxygen with glucose would have greater memory-enhancing effects than when either substance was administered alone. In a placebo-controlled study, 104 healthy adults were given a glucose or placebo drink, and inhaled 100% oxygen or air for 1 min, before carrying out a number of everyday memory tasks designed to measure short-term and long-term memory. Results showed support for the enhancing effects of oxygen (but not for glucose) on delayed recall. These findings are discussed in relation to the possible cholinergic properties of oxygen and glucose and the implications for their clinical use.

https://www.ncbi.nlm.nih.gov/pubmed/8740047

Psychopharmacology (Berl). 1996 Apr;124(3):255-60.

Oxygen administration enhances memory formation in healthy young adults.

Moss MC1, Scholey AB.
Author information

Abstract
Despite numerous studies indicating that transient cerebral oxygen depletion has a detrimental effect on cognition, surprisingly little research has examined the possibility of cognitive enhancement following elevated oxygen levels in healthy adults. Here, we present evidence demonstrating that oxygen administration improves memory formation. Inhalation of oxygen immediately prior to learning a word list resulted in a significant increase in mean number of words recalled 10 min later, compared to subjects who inhaled oxygen immediately prior to recall or to controls who underwent no intervention. In a second experiment, the learning-test interval was increased to 24 h and, again, only pre-learning (but not pre-test) oxygen administration resulted in significant memory facilitation. In experiment 3, inhalation of oxygen prior to learning was compared to inhalation of compressed air, oxygen (but not compressed air) resulted in a significant increase in word recall 24 h later. In no experiment did oxygen have a significant effect on any mood item measured. We interpret these data as indicating that increased availability of cerebral oxygen facilitates cognition, including memory consolidation. The implications for the psychopharmacology of cognitive enhancement are considered in the context of cholinergic systems and neural metabolism.