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Adult Cognition – finally you’re grown up… and your brain start to decline?

Posted: Tue, July 16, 2013 | By:

EXERCISE, FITNESS, HEALTH Exercise in Adults - A 2007 University of Maryland study shows that exercise benefits the frontal lobe (a brain region that mediates executive function) plus it delays age-related cognition decline. Another study conducted in 2006 by the University of Illinois at Urbana-Champagne concluded that, “Physical activity may be beneficial to both general and selective aspects of cognition, particularly among older adults.” A third study by University College London (2003) reported that physical exercise in midlife “was associated with significantly slower rate of decline in memory.” Researchers at Griffith Health Institute and School of Psychology (Australia) determined that physical activity in older adults Increased levels of less vigorous exercise were associated with higher IQ, but neither higher levels of vigorous exercise nor walking were associated with IQ.” (i.e., moderate regular exercise is best for brain gain.)

Running - A 2010 University of Illinois (Champage-Urbana) rodent study discovered that rats who did wheel running activated neurogenesis in the dentate gyrus of the hippocampus - a brain region that is important for memory function. This mirrored a similar study in 1999 at the Salk Institute. Nihon Fukushi University researchers in Japan, led by Dr. Kisou Kubota, determined that young people running 30 minutes a day 2-3 days a week for 12 weeks improved memory and other mental tasks on an intellectual test. The smart gains collapsed when the joggers stopped their training, implying that ongoing exercise is required to maintain the benefit. Findings were presented in San Diego at a meeting of the Society for Neuroscience. Stanford University research and John Ratey’s Spark also assert that running can delay age-related disability and prevent the onset of Alzheimer’s disease.

Strength Training - Scientists at the Brain Research Center at the University of British Columbia determined that elderly women who “strength train” do better in cognition tests than women who do toning work. Principal investigator Teresa Liv-Ambers found “encouraging” evidence of neurogenesis in brain scans of the weight-lifting women. Rat studies in Brazil - with weight-bearing rodents climbing ladders and negotiating mazes - reached parallel conclusions. The rats had considerably higher levels of B.D.N.F.; a growth factor that triggers neurogenesis.

Obesity - A 2005 Boston University study reported that obesity in men can eventually cause a decline in the brain’s cognitive abilities, particularly in learning and memory. A five-year study in France by Dr. Maxine Cournot on 2,223 men and women also concluded that obesity decreased human brain function, due to hormones secreted from fat cells, and thickening and hardening of cerebral vessels. Results were published in 2007 in the American Academy of Neurology. Another study, in Sweden, found that women aged 70-84 with the highest BMI were “the most likely to have cerebral deterioration.”

Sleep - The Sleep Research Centre at Loughborough University (UK) believes “sleep provides cerebral recovery, which will start faltering during sleep loss.” They claim “one night of sleep loss impairs the ability to comprehend a rapidly changing situation, increases distraction by irrelevant information, makes people think and plan in a more rigid and less flexible way, persevere more and be less able to produce innovative solutions to problems. The number of words in one’s vocabulary is reduced both verbally and in writing, and articulation becomes more labored and intonation becomes flatter. All these effects certainly suggest a deterioration within the frontal cortex.”

Caloric Restriction - A 2004 University of Hawaii report suggests that caloric restriction halts the decline of memory in the elderly, and decline of fluid intelligence in the elderly. A 2008 study from the Salk Institute claims caloric restriction improves memory in the elderly. Ex-Football Players - Researchers at The University of Texas at Dallas analyzed thirty-four retired NFL players via neurological and neuropsychological assessment. Four were diagnosed as having a “fixed cognitive deficit,” eight had mild cognitive impairment, two had dementia, and eight had depression. These deficits were more common than in the general population.

Exercise for Elders at-risk of Alzheimer’s disease - University of Western Australia researchers conducted a six-month physical activity intervention of 138 older adults with subjective memory impairment who were at the risk of Alzheimer’s disease. The program provided “a modest improvement in cognition over an 18-month followup program.” Report was published in JAMA 2009.

Physical Health = Fluid Intelligence - Good news! Karolinska Institutet (Sweden) research claims “fluid intelligence is fully mediated by physical health.” Not-so-good news: “crystallized intelligence…and visual spatial praxis… is partially mediated by age.”

MISCELLANEOUS FACTORS “Open To Experience” - Seek Novelty - People who are open to new experiences “are creating new synaptic connections with every new activity [they] engage in,” notes Andrea Kuszewski in a Scientific American essay. “Novelty,” she continues, “triggers dopamine, which… stimulates neurogenesis - the creation of new neurons.” Researchers at University of Georgia, Athens, determined that “the personality trait Openness to experience is associated with better memory performance - lifelong involvement in new cognitive activities can one protect from memory decline.

New Mothers - A 2010 Yale-New Haven Hospital study revealed that new mothers increased their volume of gray matter (neuronal cell bodies) in mid-brain areas. Moms who regarded their babies as “special, beautiful, ideal, perfect” experienced the biggest boosts, noted the press release. Cold Weather - Researchers at California School of Professional Psychology - Fresno, 2004, believe “persons in colder climates tend to have higher IQs.” Their findings echo earlier studies and are borne out by IQ totals in the fifty United States.

Managerial Responsibilities - Researchers from the University of New South Wales (Australia) found that when “professionals are promoted to managerial roles” their hippocampus increased in size. The hippocampus is responsible for learning and memory, and the mental demands of managing people are ” requires continuous problem solving, short term memory and a lot of emotional intelligence.”

Networking - In a Scientific American essay, Andrea Kuszewski claims that intelligence can be enhanced via “social media such as Facebook or Twitter or in face-to-face interaction.” Her explanation is that “by exposing yourself to new people, ideas, and environments, you are opening yourself up to new opportunities for cognitive growth.” In the same essay, she also promotes volunteer work, getting to know one’s neighbors, and “going out.”

Emotional IQ (EI) - If fear or anxiety floods the amygdala (our emotion center) the executive function of the prefrontal cortex declines, with a loss up to 10-15 IQ points or more, notes an article in Psychology Today. If our amygdala is activated and full of blood and oxygen, then our prefrontal cortex isn’t. People who have high EI can operate cooly with emotional issues and thus have more brain power in emergencies than people who have a “resting” IQ that’s higher, but they’re quickly stressed.

Alcohol Consumption in the Elderly - A 2011 University of Edinburgh study of “922 healthy adults about 70 years old” revealed that “moderate to substantial drinking was associated with better performance on cognitive tests than low-level or non-drinking in men and women.” In men, “wine and sherry-port consumption was associated with better verbal ability, but beer was associated with a poorer verbal ability and spirits intake was associated with better memory.” However, a UCLA study indicates that heavy drinking promotes an earlier onset of Alzheimer’s disease by 2-3 years. Researchers at Clinical Center Vojvodina (Serbia) also discovered that alcohol delirium leads to “verbal memory disorders [and] intellectual decrease and attention disorder in general.”

Khat—Leiden University studies have found that the Eastern Africa drug “impairs cognitive flexibility and updating of information in working memory” and “is associated with specific impairments in behavioral control: general slowing and less efficient resolution of response conflicts, which is likely to impair decision making.”

Marijuana - a 2008 University of Wolloongong (Australia) study determined that “evidence suggests impaired encoding, storage, manipulation, and retrieval mechanisms in long-term or heavy cannabis users.” An earlier 2004 study by McLean Hospital at Harvard Medical School suggested that “cannabis users may experience subtle neurological deficits.” 2012 research published in Proceedings of the National Academy of Sciences noted that “participants who used marijuana heavily from high school through age 38 scored 8 points lower on an I.Q. test than they had when originally tested, as 13-year-olds.”

Drug Use & IQ - Conflicting Studies? - Researchers at Cardiff University (United Kingdom) studied 14,362 Vietnam veterans in 2012 and found that those “with high IQ scores were less likely to be habitual users of cannabis… cocaine… heroin… amphetamines… barbiturates…and LSD.” Another Cardiff University study, of British born in 1958, suggested that “high childhood IQ was related to illegal drug use in adulthood.”

Sugar - Studies link high blood sugar levels in the elderly to brain damage. A report in December 2008 Annals of Neurology examined 240 people with an average age of 80 - researchers concluded that elevated blood glucose levels was injuring the dentate gyrus region of the hippocampus - a brain region responsible for memory and learning. Another study - in Vol. 10, #4 of Journal of Nutrition, Health and Aging, of 1,983 women, average age 80 - indicated that every 1% increase in glycosylated hemoglobin correlated with a risk increase of 40%. A Nature report (02/01/2012) added import to the above findings when a UCSF team led by Robert Lustig team defined sugar as “toxic” and “addictive” with dangerous similarities to alcohol and tobacco.

Head Injury - A 1996 New York University study reported that adults who incurred “whiplash” with “slight head impact” in a motor vehicle accident had a 14 point IQ loss after 20 points.

Summer Stupor - Lazy, sunbathing vacations can wither IQ, claims Professor Siegfried Lehrl of Germany’s University of Erlangen. Inactivity and dehydration reduce oxygen to the brain, dim neurons, and shrink frontal lobes. To prevent decline, Professor Lehrl suggests long walks, chess, drinking fluids, and chewing gum.

Chronic traumatic stress - A 2001 University of Michigan study reports that chronic traumatic stress, releasing elevated levels of cortisol, is associated with cognitive decrements. The neocortex and hippocampus were impacted, with deleterious effects on verbal, learning, delayed recall and visual-spatial abilities.

Obsessively Checking Electronic Messages - A survey of 1,100 British office workers was conducted by TNS Research and carried out by Hewlett Packard. It revealed that employees who obsessively check their phone calls, emails and text messages throughout the day suffer an IQ drop of 10 points. Their IQ was tested throughout the day by King’s College London University psychiatrist R. Glenn Wilson.

Smoking - Cigarette smoking is a significant risk factor for Alzheimer’s Disease, claims a 2010 study from University of California, San Francisco. A UCLA study (2010) also indicated that “heavy smoking” was associated an earlier onset of Alzheimer’s disease by 2-3 years. A University of Edinburgh study found that smoking at age 70 “was associated with impairments in general cognitive ability and processing speed.”

Amnesia - Multiple types of this disorder destroy memory functions.

Hypoxia - Hypoxia is defined as depriving the body - and subsequently the brain - of oxygen. It is often caused by shock, stroke, and heart attacks. The brain regions that are asphyxiated the most suffer the greatest debilitation.

Chemotherapy - This cancer treatment can cause temporary attention weakness, short-term memory loss, and other debilitations to cognition. Nickname for the side effect is “chemobrain.”

Cholesterol-lowering Statins - Lipitor, Crestor, Zocor and other cholesterol-lowering statins are widely-prescribed medications, but the side effects can be neurologically onerous. Here’s why - 25% of the body’s cholesterol is in the brain, where it insulates neurons in “myelin sheaths” to create strong neural connections, an essential step in concretizing memory and learning. A study published in 2003 Reviews of Therapeutics noted that more than 50% of statin users with memory problems announced that their symptoms were alleviated when they discontinued the medication. MedWatch - the FDA’s database for filing drug side effects - is filled with hundreds of reports of statin-blamed memory loss.

Toxoplasmosis gondii in Cat Feces - (this is a repeat from the first section - PreNatal) Toxoplasmosis is a parasite found in the gastrointestinal tract of cats. Transmission to humans - via feces in kitty litter boxes, soiled garden areas and children’s sandpits, unwashed fruits and vegetables, and undercooked meat - can created toxoplasmosis in humans; an estimated 2-3 billion people worldwide are infected by this protozoa. High rates exist in rural France (46% of the population), Brazil, and impoverished urban areas of Africa, the Middle East, and SE Asia, especially New Guinea. The least-infected region is South Korea, with a mere 6.7%. Toxoplasmosis is generally harmless in adults with healthy immune systems, but in immuno-compromised humans (such as pregnant women and victims of AIDS/HIV) the impact is enormous. Neurologically, it has been linked to encephalitis, brain cancer, Attention Deficit Hyperactivity Disorder, Obsessive Compulsive Disorder, schizophrenia, depression, and anxiety. Infected subjects have a lower IQ and lower probability of achieving higher education.


Religious Beliefs—An article written by Satoshi Kanazawa of the London School of Economics and Political Science, and published in Social Psychology Quarterly in 2010, reported that adults who identified themselves as “not at all religious” had an average IQ of 103.09, while those self-described as “very religious” had an average 97.14 IQ. In the United States, a survey was conducted that indicated that Unitarians, Quakers, and Jews score significantly higher on their SAT scores than other creeds. Another survey showed Episcopalians on top. New Zealand researchers at the University of Edinburgh who queried 2,300 adults determined that each 15-point increase in IQ made people “about half as likely to have strong fundamentalist views.”

Political Beliefs - Data compiled by Satoshi Kanasaw (see above) from the National Longitudinal Study of Adolescent Health (UK) says young males who describe themselves as “very liberal” had an average IQ of 106 during adolescence. Those who categorize themselves as “very conservative” have an average IQ of 95 during the teen years.

Monogamous Males - Data from the National Longitudinal Study of Adolescent Health suggests that males who value sexual exclusivity score higher on IQ tests than males favoring polygamy.

Vegetarianism - After Southampton University researchers surveyed 8,179 subjects, they discovered that vegetarians had a 105 point IQ, while carnivores had 100 IQ. The report was filed in the British Medical Journal.


High IQ Sperm and Egg Selection - With today’s numerous sperm and egg banks, prospective parents who want “designer babies” can purchase high IQ genes for in-vitro fertilization. The sperm bank “Repository for Germinal Choice” offered a Nobel prize product, and “Heredity Choice” still provides “genius sperm.” Egg-hungry individuals have placed advertisements in Ivy League newspapers offering $35,000-$50,000 for brainy ovums, and a recent Bangkok Post ad requested eggs from donors who had “more than 140 IQ.”

Artificial Wombs - A futuristic option to safeguard fetus intelligence is “artificial wombs.” These contraptions are still decades away, but imagine: fetuses would be safe inside, sheltered from chemical abuse, fed nourishing amounts of Omega-3, “exercised” regularly in rolling motions, and delivered without danger, at a healthy size. There’d be no sensory deprivation—as opponents fear—because the fetuses would be sung to, and cooed at, by recordings of their parents’ voices.

Parent Licenses - Defining parenthood as a privilege that needs to be earned, not a guaranteed natural right, would do wonders for global IQ. A variety of individuals could be exempted from procreation, child-bearing, and parenting, because they’re at-risk of potentially damaging their offspring’s cognitive abilities. People banned from baby-making could include women with “toxic wombs” due to alcohol and drug addiction, people with violent records that indicate they’d be abusive parents, and the genetically-unsuitable.

Germline Engineering - A procedure whereby genetic material is manipulated in the initial cells of a blastocyst. This process could enhance the potential child’s intellectual capacity. Germline engineering would be “inheritable” - modified genes would be passed into future generations.

References are available in Hank’s book Brighter Brains - 225 ways to elevate or injure IQ


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