Tag Archives: neuroscience

Be keen on choline

Choline is a necessary nutrient for proper human functioning, but it tends to get little attention. This is unfortunate, because a lot of people, in particular pregnant women and vegetarians, may be deficient in choline.

A neuron. Choline is necessary for nerve-signaling, synthesizing cell membranes, and is a precursor of the neurotransmitter acetylcholine. Image source: Wikipedia

A neuron. Choline is necessary for nerve-signaling, synthesizing cell membranes, and is a precursor of the neurotransmitter acetylcholine. Image source: Wikipedia

Choline is usually considered part of the B vitamin club. Or maybe it is more like a “fellow traveler”. Whatever the case, choline is a quaternary ammonium salt that is used to synthesize cell membranes, for energy production, and also for nerve signaling. It appears to be particularly important for proper brain, and liver functioning.

Choline is also a precursor molecule for making acetylcholine, an important neurotransmitter in the brain that is important for memory and muscle control. Fatty organ meat is the best source of choline, and eggs(the yolk) to a lesser extent, though it can also be found in plant foods like nuts, whole grains and green vegetables, but in smaller amounts. Lecithin, which is used as an emulsifier in food production and as a supplement also has a lot of choline. A healthy person can make their own choline from the amino acid methionine, but many people don’t produce enough.

Unlike most nutrients, choline doesn’t have an RDA(recommended daily allowance). It does, however have an AI(adequate intake, which is 550 milligrams per day for men and 425 for women which was set in 1998), which means experts can’t agree on an RDA since the science is less clear for choline than for nutrients with RDAs, like vitamin C, calcium, vitamin A, and iron, among others. Not getting the RDA for vitamin C can lead to a deficiency disease called scurvy, which is characterized by bleeding gums, weakness, and bone pain.

Lack of choline, on the other hand, doesn’t necessarily lead to any chronic, debilitating deficiency disease, except for non-alcoholic fatty liver disease, in many, but not all people who get inadequate choline. According to –  Choline
Dietary Requirements and Role in Brain Development
Lisa M. Sanders, PhD, RD and Steven H. Zeisel, MD, PhD:

When placed on a low-choline diet, only 68% of individuals developed signs of organ dysfunction characteristic of choline deficiency. This suggests that genetic variability among individuals may influence susceptibility to choline deficiency.

So your genes can determine whether or not you show symptoms of choline deficiency. This is one very complex nutrient which is involved with so many metabolic pathways. Most pregnant women do not get adequate choline(in theory, they require more), however, supplementing with choline didn’t appear to help enhance infant cognitive function, according to: Am J Clin Nutr. 2012 Dec;96(6):1465-72. doi: 10.3945/ajcn.112.037184. Epub 2012 Nov 7:

RESULTS:

The women studied ate diets that delivered ∼360 mg choline/d in foods (∼80% of the recommended intake for pregnant women, 65% of the recommended intake for lactating women). The phosphatidylcholine supplements were well tolerated. Groups did not differ significantly in global development, language development, short-term visuospatial memory, or long-term episodic memory.
CONCLUSIONS:

Phosphatidylcholine supplementation of pregnant women eating diets containing moderate amounts of choline did not enhance their infants’ brain function. It is possible that a longer follow-up period would reveal late-emerging effects. Moreover, future studies should determine whether supplementing mothers eating diets much lower in choline content, such as those consumed in several low-income countries, would enhance infant brain development.

What about choline’s effect on dementia, since choline is a precursor for acetylcholine, which is important for brain health and memory production? According to – Clin Ther. 2003 Jan;25(1):178-93:

RESULTS: A total of 261 patients (132 in the CA group, 129 in the placebo group) were enrolled in the study. The mean (SD) age in the CA group was 72.2(7.5) years (range, 60-80 years), and in the placebo group it was 71.7 (7.4) years(range, 60-80 years). The CA group comprised 105 women and 27 men; the placebo group, 94 women and 35 men. The mean decrease in ADAS-Cog score in patients treated with CA was 2.42 points after 90 days of treatment and 3.20 points at the end of the study (day 180) (P < 0.001 vs baseline for both), whereas in patients receiving placebo the mean increase in ADAS-Cog score was 0.36 point <1 after 90 days of treatment and 2.90 points after 180 days of treatment(P < 0.001 vs baseline). In the CA group, all other assessed parameters (MMSE,GDS, ADAS-Behav, ADAS-Total, and CGI) consistently improved after 90 and 180 days versus baseline, whereas in the placebo group they remained unchanged or worsened. Statistically significant differences were observed between treatments after 90 and 180 days in ADAS-Cog, MMSE, GDS, ADAS-Total, and CGI scores and after 180 days of treatment in ADAS-Behav and GIS scores.CONCLUSION: The results of this study suggest the clinical usefulness and tolerability of CA in the treatment of the cognitive symptoms of dementia disorders of the Alzheimer type. (Emphasis mine)

So choline shows some promise when it comes to symptoms of dementia and Alzheimer’s, but more research needs to be done. Some good sources of choline:

Food Serving Total Choline (mg)
Beef liver, pan fried 3 ounces* 355
Wheat germ, toasted 1 cup 172
Egg 1 large 126
Atlantic cod, cooked 3 ounces 71
Beef, trim cut, cooked 3 ounces 67
Brussel sprouts, cooked 1 cup 63
Broccoli, cooked 1 cup, chopped 62
Shrimp, canned 3 ounces 60
Salmon 3 ounces 56
Milk, skim 8 fl oz. 38
Peanut butter, smooth 2 tablespoons 20
Milk chocolate 1.5-ounce bar 20

Source: Linus Pauling Institute of Oregon State University

None of this should be considered a recommendation to take choline supplements(or to eat a lot of meat), though if you look at the chart above it becomes obvious that vegetarians are more likely to become deficient than meat-eaters. Be on the look out for news about choline, and it may be worth talking about choline with your doctor if you show any deficiency symptoms. In the future, maybe there will be a simple liver test to see if we need more choline in our diet.

Musicians have larger corpus collosums

The benefits of playing a musical instrument are many, but did you know that if you learned to play an instrument early enough you may have a much larger corpus collosum than non-musicians?

What is this strange thing you ask? No no no, it is not what you are sitting on, that is the gluteus maximus. The corpus collosum(CC) connects the right and left hemispheres of the brain. It’s basically a bridge, but don’t tell the government or they will put tolls on it. Anyway, the CC appears to be significantly larger in musicians who started studying music before the age of 7:

Using in-vivo magnetic resonance morphometry it was investigated whether the midsagittal area of the corpus callosum (CC) would differ between 30 professional musicians and 30 age-, sex- and handedness-matched controls. Our analyses revealed that the anterior half of the CC was significantly larger in musicians. This difference was due to the larger anterior CC in the subgroup of musicians who had begun musical training before the age of 7. Since anatomic studies have provided evidence for a positive correlation between midsagittal callosal size and the number of fibers crossing through the CC, these data indicate a difference in interhemispheric communication and possibly in hemispheric (a)symmetry of sensorimotor areas. Our results are also compatible with plastic changes of components of the CC during a maturation period within the first decade of human life, similar to those observed in animal studies.

Studies like this are basically studying this really neat property of the brain called neuroplasticity. This basically means the brain can adapt or form new connections in response to learning. The brain adapts to learning how to juggle in a similar manner to how it adapts to learning to play an instrument. But you knew that already.

While brain plasticity is a feature of the brain at any age, young brains are more plastic than older ones. As the study suggested, the musicians with the much larger corpus collosums had been playing an instrument before age 7; learning after this age may not have the same permanent effect on optimizing growth of the corpus collosum.

This suggests a window of opportunity in learning things. The window isn’t completely closed after a certain age, there are after all many amazing musicians who started to learn to play well after age 7 obviously. On the other hand, how many 40 year old world famous virtuoso pianists are out there who have only been playing since the age of 35? Besides me, of course?

At this stage of research, we don’t really know if having a larger CC actually means a person is smarter(children who play an instrument regularly tend to do better in school, but that doesn’t mean that being a musician necessarily makes them smarter). On the other hand, it can’t be a bad thing. And since we are on the subject of the bridge between the left and right hemispheres of the brain, remember that the differences between the right and left hemispheres are mostly a myth. A very stubborn myth too.

Even if you can’t stimulate your corpus collosum to grow bigger after a certain age, keeping your brain active by learning something new is still the best way to keep your brain healthy.

Experiencing ASMR

ASMR(autonomous sensory meridian response) is not a well-known phenomenon, but many people, including myself, claim to experience it on occasion.

What is ASMR? It is a strange, pleasurable tingling sensation that you feel mostly on the back of your head and neck, and sometimes along your spine. It usually happens in response to doing something you find very enjoyable. For some people it accompanies euphoria and is sometimes called a “braingasm” for this reason.

Since it is a very subjective experience, it is very difficult for science to study it. Indeed, this response wasn’t even known at all until many people who claim to experience it congregated over the Internet a few years ago and started websites and message boards devoted to exploring it.

Sometimes juggling brings about ASMR in me, especially if I finally figure out how to do a new trick. In fact, on long joggles I often experience it(it is related to, though not the same thing as “joggler’s high“), especially if I have beautiful music playing in my mind(I never listen to music from an mp3 player or anything during runs). It also helps if I am joggling through rocky, difficult terrain in a wooded area and have gorgeous untamed wilderness full of birdsong all around. It’s like merging into a divine symphony of nature, music, dance, and beauty all interwoven into one.

Music alone can also bring about this response in me, along with reading something inspiring, discovering something new, or a “eureka!” moment when I solve a complex problem. Sometimes finding bizarre links between completely unrelated subjects leads to this response. Certain types of sounds trigger it in many people, and there are even people who produce Youtube videos to help bring about this response in others. It feels sort of like a “bizarre euphoria”.

A good massage, certain aromas, or even exercising may also bring about ASMR. Dr Steven Novella, a neurologist at Yale and head of the New England Skeptical Society suggests that ASMR may even be a pleasurable type of seizure:

Looking back as a neurologist I have wondered what they were. They could even have been little seizures. Seizures can be triggered by auditory stimuli. Perhaps ASMR is a type of seizure. Seizures can sometime be pleasurable, and can be triggered by these sorts of things.

You can read the rest of his post about ASMR here. His Neurologica blog is one of the best science blogs out there by the way, and I highly recommend it. As far as it being a type of seizure, I really have no clue, but I suppose it is possible and it vaguely feels like one.

Due to its subjective nature, many experts may even question if this response even exists. We’re all so different, so are all these different people who claim they are experiencing ASMR really experiencing ASMR? Will science figure out what this is all about?

Our peak experiences in life were likely accompanied by ASMR. Has anyone reading this experienced ASMR?

Parkinson’s Disease and physical activity

Parkinson’s disease is a disorder of the central nervous system that slowly leads to almost total loss of motor function. At later stages, it can lead to dementia. The ultimate cause of this disease is not known, though genetics and exposure to toxins appears to play an important role. The proximate cause appears to be an accumulation of proteins in certain neurons, and lack of dopamine in the parts of the brain responsible for movement. “The discovery of dopamine deficiency in the parkinsonian brain” by Dr. O. Hornykiewicz gives a detailed account of how scientists unearthed the link between dopamine deficiency and Parkinson’s disease.

Parkinson’s disease is currently incurable, but it can be treated in its early stages by drugs and other interventions. As time goes by, and the disease progresses, these drugs become less effective. At more advanced stages, doctors may implant electrodes in the brain to provide “deep brain stimulation”, but not everyone responds well to such treatments.

Placement of an electrode into the brain. From Wikipedia.

Placement of an electrode into the brain. From Wikipedia.

There are of course other, less invasive ways to stimulate the brain to slow down the progression of the disease. According to research done by Rose MH, Løkkegaard A, Sonne-Holm S, Jensen BR, at the University of Copenhagen, high-intensity locomotor training can greatly improve Parkinson’s symptoms. Similar research conducted by Cakit BD, Saracoglu M, Genc H, Erdem HR, Inan L., at Ankara Education and Research Hospital, Turkey, show treadmill training can improve mobility in Parkinson’s patients, and reduce their fear of falling.

So it appears that regular exercise in the early stages of Parkinson’s can slow down the disease’s progression, with or without medication. David H. Blatt, M.D., who is himself a Parkinson’s sufferer and runs the website, Exerciseforparkinsons.com, recommends regular exercise to treat Parkinson’s, especially learning how to juggle. In his own words:

I believe that by practicing juggling I have substantially slowed the progression of my Parkinson’s disease. Juggling stimulates the brain – it forces the brain to quickly process complex, sensory input and then it forces the brain to direct muscles to move quickly in a complex, coordinated manner.

He has many inspiring videos on his website which demonstrate the benefits of his approach. Juggling and exercise may prevent other neurological conditions besides Parkinson’s, as my previous post demonstrated. I would love to see some studies to see if and how juggling helps Parkinson’s patients. As time goes by, the list of benefits of juggling and exercise in general continues to grow.