Archive for the ‘Brain Basics’ Category
Message: Necessary as air means most necessary. Our breathing process is unique in many ways. Everyone knows how long a man can live without food, water and air. Without air — almost no time. A few minutes, and brain cortex dies. Also unique is the availability of air: so far no one came up with a way to sell it. Finally, unique is the process’s character which is almost automatic. Almost. That’s the topic for today.
To Breathe or not to Breathe?
“…look, everybody breathes in pure oxygen, but tries to breath out all kinds of filth!”
A. Raikin
A man is sitting in a closed room and is doing something. The window is closed, the air conditioner is off. Oxygen is consumed, carbon dioxide is exhaled, thus increasing the CO2 concentration in the room. What happens?
None can say for sure! In a short period of time a number of following might change:
- Breathing depth
- Breathing frequency
- Heart’s contraction strength
- Pulse
- Blood flow velocity
- Blood vessel resistance
- Oxygen availability to tissues (how easily it is transferred from hemoglobin into tissues)
In a longer period of time, something else will change:
- Lungs’ vital capacity (how much air is taken in for the deepest breath)
- Amount of hemoglobin
- Amount of erythrocytes (red blood cells carrying oxygen)
- Eritropeses (production of erythrocytes in bone marrow)
Your breathing function is affected by the combination of all these parameters which in turn are related to each other, how — it’s impossible to predict. Moreover, each time, random combination might “fall out.” So when something changes in the oxygen availability to tissues or you change your breathing, your body brilliantly evades to compensate for those changes.
So do we need to control our breathing?
Seems that a healthy animal or a child has no need to. Some breathing techniques manuals instruct to uncover a baby and see how rhythmically it’s stomach rises and falls. The chest barely moves. That type of breathing is called diaphragmal, because the diaphragm, a muscle between the chest and stomach is the one that makes the lungs expand and contract. That type of breathing is meant for quiet body state.
When an awakened baby cries, it is visible that the chest starts working to take in as much air as possible. It is an emergency breathing. It is meant for stress and hard physical efforts. In rest, the body functions’ control is overrun by parasympathetic autonomous nervous system. In emergency cases — it is taken over by a competitive nervous system, the sympathetic one. It increases body’s work in order to escape a predator, chase a prey, or endure fear or rage. For example, the heart rate is increased, blood vessels contract to avoid losing too much blood in case of a wound, and so on. Functions that are not immediately needed, like intestinal movement, are slowed down.
Several US universities have developed the test predicting the development of premature babies. If the control of parasympathetic system is dominating, the prognosis is definitely better: the possibility of cerebral palsy, mental retardation and other typical pathologies of premature babies, is much less. Domination of the sympathetic nervous system, in babies as well as in adults, on the other hand provides for not so good a prediction. Of course, the body is more comfortable under the parasympathetic control, and the latter is dominant until something out of the ordinary happens.
Nevertheless, like in many other cases, we are deviating from the natural order of things. In this case, it is an abuse of the sympathetic system’s services. Hence are the tendencies to high blood pressure, increased pulse, etc. Hence is the emergency type of breathing when it is not needed.
Try breathing as deep and as fast as you can. Soon, you will get dizzy and might even get a headache. Asthma victims might get an asthma attack. People with heart problems might get an angina attack… >> Read more
Message: Should you go for hormone replacement therapy? Should you avoid hormonal contraceptives?
In late 1990s, studies seemed to prove estrogen (estradiol-based) hormone replacement therapy protects nervous and other brain cells against a variety of harmful impacts. However, later the Women Health Initiative study not only failed confirming this finding but instead showed an increased risk of cognitive impairment, dementia and stroke on combined estradiol/progesteron therapy. This caused fear of hormonal contraceptive pills. However, these two groups of findings, as new data showed, do not contradict each other. Turns out that estradiol loses its neuroprotective activity or can even increase brain damage as a woman ages and her hormonal levels drop.
Source:
Trends in Endocrinology and Metabolism, December 2011, Vol. 22, No. 12
Message: there are many supplements on the market believed to postpone brain aging but they are still on clinical trials. To wait until consensus is reached or to go for them since they wouldn’t hurt depends (mostly) whether you can afford them or not.
Vitamins E and C, alpha-lipoic acid, creatine, melatonin, omega-3 polyunsaturated fatty acids, CoQ10, curcumin, resveratrol, glucose, malate and other antioxidants and (and their combinations) are subjects of around 30 registered clinical trials investigating diseases blamed for the consequences of brain aging — Alzheimer’s and Parkinson’s diseases and amyotrophic lateral sclerosis.
Source: Journal of Alzheimer’s Disease 25 (2011) 187–208
Message: Meditation can prevent brain cortex loss
Magnetic resonance imaging to assess cortical thickness revealed that brain areas—such as the prefrontal cortex involved with memory, attention, and sensory processing—were approximately 5 percent thicker in the subjects who meditated compared with those who did not. This difference was most pronounced in older participants, suggesting that meditation might offset agerelated cortical thinning.
Source: Neuroreport 2005;16:1893–1897
Message: The sense of balance is important for intelligence
Exercise can help maintain balance, and balance in the elderly has been highly correlated with performance measures of mental abilities such as general intelligence, memory, and reaction time. Balance thus serves as a biomarker of cerebroarterial blood flow and age-related global neurophysiologic status.
Source: Neuropsychologia 2006;44:1978–1983).
Message: Managing insulin resistance can help prevent mental problems
The metabolic syndrome’s area of influence seems to be growing startlingly fast. Latest research revealed its link to mental health problems. Researchers discovered that insulin resistance can be “in your head” and created a new medical term, the “type 3 diabetes” referring to the newly discovered insulin receptors in the brain.
Researchers at Rhode Island Hospital showed that insulin resistance is tied to neurodegeneration. A drop in insulin production in the hippocampus — the part of the brain responsible for memory — can contribute to early stages of Alzheimer’s disease. In the frontal cortex of the brain, a major area affected by Alzheimer’s, the levels of insulin receptors and the brain’s ability to respond to insulin decreased.
Whether or not an insulin shortage causes a breakdown in brain cell communication, which would explain another brain disease, schizophrenia, remains unknown, but people with schizophrenia are at least twice as likely to develop Type 2 diabetes. ”There’s a whole series of steps that may prevent the schizophrenic brain from responding to insulin,” said Dr Altar of the Psychiatric Genomics Center in Boston, which is now focusing on potential treatments for schizophrenia.
Sources:
- Dementia and Geriatric Cognitive Disorders, 2007;23:29-34
- JAMA. 2004; 292:2237-2242
- J Alzheimer’s Disease; March 2005
- J Alzheimer’s Disease; November 2005
Related:
If we could delay the onset of dementia by 2 years, we could reduce its risks by as much as 25% — all other things being equal — and one of the most effective and simple ways is physical activity (Am J Public Health 1998;88:1337– 42). Drs Rockwood and Middleton from Dalhousie University, Halifax, Canada, analyzed 7 studies of exercise effects on risks of dementia and concluded that, without exception, 65 to 93 years old men and women who exercise the most have a lower risk of dementia relative to those who exercise the least. (Alzheimer’s & Dementia 3 2007; S38–S44)
Another, large-scale study found a significant dose-response relationship between physical activity and cognitive function was conducted as part of the Nurses’ Health Study in 18,766 women (JAMA 2004;292:1454–61). After about 10 or more years, when the women were 70 to 81 years old, those reporting the most physical activity scored higher on several baseline tests of cognitive function. During the 2 years of additional follow up, there were again significant trends for a dose-response relationship in which those reporting the most physical activity exhibited the least decline in cognitive function (JAMA 2004;292:1454–61).
Even walking was associated with a “dose-dependent” risk reduction: those walked at an easy pace for at least 1.5 hours per week had significantly higher cognitive scores than those walking less than 40 minutes per week.
Higher activity levels might not be necessary for the benefit (Alzheimer Dis Assoc Disord 2004; 18:57– 64) – an increase of 30-minutes aerobic exercise frequency from 3 to 5 times per week did not result in a proportional decrease of cognitive decline in a group of 1146 women 65 years old or older.
However, for those in the higher-intensity exercise group, that worked out at least moderate intensity (more vigorously than walking), or for longer durations each day (Med Sci Sports Exerc 2001;33:772–7.) chances of cognitive impairment, Alzheimer’s, or all-cause dementia were lower (Arch Neurol 2001;58:498 –504).
Message: Walk!
If we could delay the onset of dementia by 2 years, we could reduce its risks by as much as 25% — all other things being equal — and one of the most effective and simple ways is physical activity (1). Drs Rockwood and Middleton from Dalhousie University, Halifax, Canada, analyzed 7 studies of exercise effects on risks of dementia and concluded that, without exception, 65 to 93 years old men and women who exercise the most have a lower risk of dementia relative to those who exercise the least (2).
Another, large-scale study found a significant dose-response relationship between physical activity and cognitive function was conducted as part of the Nurses’ Health Study in 18,766 women (3). After about 10 or more years, when the women were 70 to 81 years old, those reporting the most physical activity scored higher on several baseline tests of cognitive function. During the 2 years of additional follow up, there were again significant trends for a dose-response relationship in which those reporting the most physical activity exhibited the least decline in cognitive function (3).
Even walking was associated with a “dose-dependent” risk reduction: those walked at an easy pace for at least 1.5 hours per week had significantly higher cognitive scores than those walking less than 40 minutes per week.Higher activity levels might not be necessary for the benefit (4) – an increase of 30-minutes aerobic exercise frequency from 3 to 5 times per week did not result in a proportional decrease of cognitive decline in a group of 1146 women 65 years old or older.However, for those in the higher-intensity exercise group, that worked out at least moderate intensity (more vigorously than walking), or for longer durations each day (5) chances of cognitive impairment, Alzheimer’s, or all-cause dementia were lower (6).
Sources
- Am J Public Health 1998;88:1337– 42
- Alzheimer’s & Dementia 3 2007; S38–S44
- JAMA 2004;292:1454–61
- Alzheimer Dis Assoc Disord 2004; 18:57– 64
- Med Sci Sports Exerc 2001;33:772–7
- Arch Neurol 2001;58:498 –504
Related:
Message: Know the enemy!
• Alzheimer’s affects approximately 4.5 million Americans and is
expected to affect up to 16 million by 2050.
• Alzheimer’s affects approximately 5 percent of men and women
ages 65–74.
• Nearly half of people 85 and older have Alzheimer’s.
• Alzheimer’s must be distinguished from mild cognitive impairment
and normal age-related memory changes.
Source: National Institute of Aging. Alzheimer’s Disease Information, May 9, 2006
Exercise during midlife comparing with exercise during late life
Most of the studies into the protective effects of exercise against cognitive decline, dementia, and Alzheimer’s disease, followed the elderly people starting their 65s and watched the results, which were relevant to the beneficial effects in late life. However, there are some results where a large cohort of 65-79-year olds has been followed-up for around 21 years so information about physical activity during midlife was available. Those who who participated in at least “leisure-time physical activity” during midlife had significantly lower risks of dementia or Alzheimer’s disease comparing with those who did not exercise at all [1].
Another study has suggested that physical activity at even earlier ages (physical activity between ages 15 and 25 years was asked retrospectively) can improve or preserve cognitive ability in late life [2]. This cognitive decline risk reduction is at least comparable to the eisks reduction reported in studies of physical activity in older persons. Thus, midlife physical activity might be as important for preventing later cognitive decline as is physical activity at older ages.
Sources
- Rovio S, et al. Leisure-time physical activity at midlife and the risk of dementia and Alzheimer’s disease. Lancet Neurol 2005;4:705–11
- Dik M, Deeg DJ, Visser M, Jonker C. Early life physical activity and cognition at old age. J Clin Exp Neuropsychol 2003;25:643–53
Message: Next time you crave anything, ask yourself “What is it I really need? A glass of water? A walk? A hug?” Buying fresh flowers can be a better answer than a bowl of Rocky Road. Exercise, go to sauna, take a cold shower, invest in a massage device, buy a vail of perfume, enjoy a book… Try periodic fasts. After resuming eating, your taste buds will be satisfied with lesser taste intensity thus reducing the taste influence on the body weight set point.
Reward: it can be not about food
“Something is wanted — either a constitution or a piece of sturgeon under horseradish sauce.” M.E. Saltykov-Schedrin (19th Century)
In the late 50s, the classic experiments by Dr. Olds shook the world. He implanted electrodes into certain regions of rat brains and taught the rats how to press lever to stimulate these regions with weak electric currents. Rats stopped doing anything but pressing the lever till their death from complete starvation. The Positive Reward theory was born. It turned out that anything pleasurable in life did related to these “Centers of Pleasure” — sex, alcohol, drugs of abuse — all that mankind has invented in its hedonic journey, were but attempts to stimulate these brain regions.
We know that eating will produce a pleasant sensation so often we eat even though all we need is comfort. The truth is, exercise, sauna, cold shower, massage, pleasant odors, and mental efforts (workoholism is real!) — all increase Endorphin level while only eating, especially when your body does not need it, will cause extra pounds of fat to collect in your body’s store.
“A mechanism for opiate [e.g. endorphin] mediation of food intake was postulated. It starts with a feeding initiating signal, which produces activation of the receptors, thereby inducing eating. Eating produces a circular reaction starting with hedonic input from the eating [process]. This, in turn, produces reward, which causes further eating, completing the circle” [1].
Fasting can be as rewarding
The tricky thing with endorphins is that there are pairs of releasers resembling a thesaurus’ antonyms: exercise does the same os its antonym sleep, pleasure goes together with pain, local blood flow increase does the same to endorphin release as the local lack of oxygen. The eating-fasting pair also exists. Many people reported elation when they skipped breakfasts. Religeous fasters experience euforia.
“Severe food restriction produces opiate activity, which is reinforcing. Feeding interrupts the opiate activity and, thus, produces withdrawal. Not eating, therefore, is rewarding.” [2].
Sources
- Soc. Neurosci. Abstr. 18:369; 1992
- Appetite 19:1-13; 1992
Read also: A theory of acupuncture, spinal cord, and endorphins
