Non-neurotic extraverts don't dement!

Just untangling the conclusions of this Swedish study was a brain workout in its own right, a downright 'how much wood would a woodchuck chuck..." sort of puzzle:

Neither high neuroticism nor low extraversion alone was related to significantly higher incidence of dementia. However, among people with an inactive or socially isolated lifestyle, low neuroticism was associated with a decreased dementia risk (hazard ratio [HR] = 0.51, 95% confidence interval [CI] = 0.27-0.96). When compared to persons with high neuroticism and high extraversion, a decreased risk of dementia was detected in individuals with low neuroticism and high extraversion (HR = 0.51, 95% CI = 0.28-0.94), but not among persons with low neuroticism and low extraversion (HR = 0.95, 95% CI = 0.57-1.60), nor high neuroticism and low extraversion (HR = 0.97 95% CI = 0.57-1.65).(1)

Got it? So do we fret and socialize, stay home and calmly knit, or placidly go out drinking with our buddies? Don't freak out while you discuss this conundrum with your friends because, as you will see once you sort out the various possibilities here, being a Buddha of a buddy is your best bet for the brightest brain.
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Wang, HX, et al. Personality and lifestyle in relation to dementia incidence. Neurology. 2009 Jan 20;72(3):253-9.

Rats! It's Welch's!

The average rat lives for 24 months. A 19 month old rat, therefore, is getting on in months and may well be on its way to becoming a doddering old rodent. In an effort to see if rats could retain their marbles well into their second year, investigators at Tufts University encouraged an aging rattine* group to exclusively drink Concord grape juice from the age of 19 to 21 months. One group knocked back a 50% concoction, another a 10% brew, and a confused final group got no grapes at all.

The half-strength gang excelled at motor skills (the team reported that this group of elderly daredevils were able to hang onto a wire for two seconds longer than all the rest -- suspended perhaps above a pen of hungry cats?). The ten-percenters, on the other hand, mastered a Morris water maze with an ease that shamed their thrashing colleagues, and then they oozed far more dopamine from their striatal slices -- this after they no longer needed their brains to stay afloat -- in a manner not usually seen in aging vermin.

The implications for those of us humans attempting to hang onto our aging brains but not necessarily wires? Dr. John Folts of the University of Wisconsin concludes that "a good antioxidant might be helpful" to old neurons. I don't know about you, but I've switched to Welch's as my a.m. juice du jour.
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*Just to prove you can find anything on the internet, check out the discussion on ratty adjectives at Ratty and rat rights.

Docosahexaenoic acid or DHA

DHA is an appealing PUFA (poly-unsaturated fatty acid) delivered by fish oil. French investigators theorize that this PUFA or omega-3 fatty acid becomes incorporated into the cell membranes of neurons. Once embedded in the cellular surface, DHA may protect against the injurious effects of beta-amyloid, the protein fragment that gums up the brainworks in Alzheimer's disease.

And in clinical news, a decade long study of Boston old fogies* showed a 48% decrease in the incidence of AD among those who had the highest levels of DHA from their regular intake of fatty fish.

Lead author, Tufts scientist Dr. Ernst Schaefer had this to say "These dramatic results show how older adults can play a significant role in their neurological health by increasing their intake of fish, fish oil or especially, DHA."
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*Arch Neurol. 2006 Nov;63(11):1545-50.

Silent brain infarctions

...and no air through the airway means no oxygen to the brain!

Clinically identified stroke represents the tip of the iceberg in terms of cerebral vascular disease by at least an order of magnitude...It is hard to believe, however, that loss of brain tissue should go without consequences. The brain may reorganize functional networks to adapt to lesions and recover function. But with each subsequent stroke, the capacity to do so is diminished.
--Brian J. Murray, MD

Silent brain infarctions or SBIs occur when a small amount of brain tissue is lost due to a lack of oxygenated blood to the area caused by a blockage in its blood supply. While any one such event can pass unnoticed, the cumulative damage from many such events builds up over time until the loss is manifested by neurological symptoms such as confusion or unsteadiness with walking. Nursing homes are filled with old ladies who lost their independence piecemeal in just such a fashion.

Scary new news on SBIs--one-fourth of persons with obstructive sleep apnea (the bedmate who keeps you awake as you lie awake waiting for him to take his next breath) were found in a Japanese study to have evidence of extensive silent strokes on MRI imaging.

How do you know if you've got sleep apnea if no one is lying awake waiting for you to breathe, and then telling you about it in the morning? Excessive daytime sleepiness,* a high red blood cell count, hypertension, and a short, thick neck are often associated with this dangerous condition.
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*As your oxygen levels drop off when you stop breathing, brain sensors rouse you to near consciousness to get you to make that big, annoying (to your bed partner) gasp for breath. While you may not be aware that you are waking up multiple times during the night, the lack of deep levels of sleep leaves you heavy-lidded by early afternoon.