Effects of Oxygen Concentration on Cognitive Ability
By: Sai Srihaas Potu
Gaining insights into brain oxygen metabolism has been one of the key areas of research in neuroscience. Extensive efforts have been devoted to developing approaches capable of providing measures of brain oxygen metabolism not only under normal physiological conditions but, more importantly, in various pathophysiological conditions as well.
The brain depends almost entirely on oxidative metabolism to meet its significant energy requirements. As such, the cerebral metabolic rate of oxygen (CMRO2) represents a key measure of brain function. Quantification of CMRO2 has helped elucidate brain functional physiology and holds potential as a clinical tool for evaluating neurological disorders including stroke, brain tumors, and Alzheimer’s disease.
The brain has a high energy demand and reacts very sensitively to oxygen deficiency. Neurobiologists at Ludwig-Maximilians-Universitaet (LMU) in Munich have now succeeded for the first time in directly correlating oxygen consumption with the activity of certain nerve cells.
The brain requires a disproportionate amount of energy compared to its body mass. This energy is mainly generated by aerobic metabolic processes that consume considerable amounts of oxygen. Therefore, the oxygen concentrations in the brain are able to influence the function of nerve cells and glial cells. However, the amount of oxygen consumed in the brain and how this is related to neuronal activity is largely unknown. LMU neurobiologists Hans Straka, Suzan Özugur, and Lars Kunz have now succeeded for the first time in directly measuring this in the intact brain and correlating it with nerve cell activity.
In an already established animal model – tadpoles of the clawed frog Xenopus laevis – the scientists used electrochemical sensors to determine the concentration of oxygen in the brain and one of the brain ventricles. They were able to specifically control the amount of oxygen available to the brain as well as inhibit nerve cell activity with the help of pharmacological substances. Using the example of nerve cells that control eye movements, the scientists succeeded in directly recording the relationship between oxygen consumption and nerve cell activity. “We have found that the brain is anoxic in a normal air-saturated environment, which means that no oxygen can be measured,” says Straka.
The oxygen was therefore immediately used by the cells to synthesize energy-rich substances. If more than twice the atmospheric oxygen concentration was available, the energy metabolism was saturated, and oxygen was abundantly present in the brain. “We were also able to show that during normal operation only about 50 percent of the oxygen is used for nerve cell activity,” says Straka. “So, the other 50 percent is required for glial cells and for maintaining the basic metabolic rate of nerve cells. However, nerve cells with increased activity consume more oxygen.”
In order to better understand how information is processed in the brain, knowledge of the relationship between oxygen availability and brain activity is essential. The scientists’ results provide initial insight into this relationship and are an important basis for further investigations of the brain’s energy balance and for measuring oxygen consumption for various nerve cell functions. This could also be relevant from a medical point of view, for example, to better understand the consequences of oxygen deficiency in the brain or to better interpret the information on brain activity obtained with imaging techniques.
The brain is one of the most integral parts of our body. Without proper oxygen flow to the brain, many different neurological functions are hindered. To prevent this from happening, there are many things that we can do at home in order to enhance our oxygen flow. Your brain needs a constant supply of oxygen for its proper functioning. This boosts your oxygen intake, benefiting your entire body and brain. To help enhance this process, doctors recommend emptying your chest as you slowly draw your abdomen inwards to let all the air out from your lungs. Begin and end your day by doing 20 to 25 rounds of this deep-breathing exercise. Subsequently, it is important to align your spinal cord in order to promote the delivery of oxygen to your brain, however, holding any position for extended periods of time can hinder cerebral circulation.
Oxygen helps your brain to function, but many of your daily activities or habits may inhibit the circulation of blood, oxygen, and other nutrients to your brain and throughout your cerebrospinal system. While extensive efforts have been devoted to developing approaches capable of providing quantitative measures of cerebral oxygen metabolism, researchers still need to continue to find different methods that will help find a correlation between oxygen rates and brain activity in order to find better cures for some of the most prevalent neuropsychological disorders.
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