Sunday, July 20, 2014

Too hungry to think - brain will sacrifice memory when you're starving

Ever experience "brain fog?" That feeling where you're so tired, you can't make sound decisions?

I did a previous post about the science behind "hangry" pangs, but what about how being hungry affects our thinking?

Our brain works hard for us everyday. Whether it's trying to remember what items to pick up at a store, solving a Sudoku puzzle while waiting for the bus, or stealthily maneuvering your car through the tricky traffic hour - our brain is phenomenal... at a cost. To operate at its fullest capacity, the brain is a metabolically demanding organ. In fact, it's probably the most demanding organ in your body, requiring nutrients like sugars to continue to function properly.

So what happens when you're running on fumes, low on energy? It's happened to all of us at some time or another. Maybe you were trying to meet a deadline and forgot to eat lunch, or you were too excited shopping to stop and grab a bite. Whatever the reason, no one can deny the end result of trying to use your brain, usually unsuccessfully, when on an empty stomach. I even think that a hungry brain is probably worse than a sleepy brain... maybe.

It seems that nature has a way of trying to save every ounce of energy in order to survive, even if it is at the expensive of using your noggin. In the instances when an organism is facing a shortage of food, the brain will forgo costly memory in order to survive. Don't believe me? It's true - at least in flies, that is.

Photo courtesy of A. Rivera
In an article published in Science last year, scientists found that starving flies switch to a cheaper form of memory as a way to avoid high usage of their energy stores. Flies have two types of aversive memory (memory that a particular odor or food is bad for you or tastes gross)*: one type of aversive memory is highly expensive, but lasts long - this type of memory requires the creation of new proteins. The second type of aversive memory is the cheaper, bargain brand alternative. This cheaper memory doesn't require protein synthesis, but doesn't last as long as the expensive memory type. What researchers found was that while regularly fed flies use the expensive memory type, starving flies switch to the cheaper alternative. In this situation, it appears that the brain shuts down the default expensive memory to save on energy.

Why even switch memory types? The long term memory that lasts longer is just too costly. The brain seems to be weighing costs of using different types of memory - this is a great case of adaptive plasticity, where the body is adjusting to the environment appropriately. For flies, starving flies shut down the machinery that uses costly memory. Exactly how costly is this memory? Researchers found that mutant flies that used more expensive memory and less cheap memory actually had shorter lifespans than control flies. In this instance, it actually kills to use your brain! (a bit dramatic, but you get the point)

Although there haven't been any findings that show this same phenomenon in mammals, it would be interesting to consider how this could be affecting humans. In the short term, it probably doesn't matter what type of memory you're using (as in, doesn't matter how you get to a point, so long as you get there, right?). However, in the long term, using the cheaper memory may have its pitfalls. If similar to flies, the cheaper memory doesn't last as long as the more expensive brand - in this case, you may find that your precious memories are at risk for being erased. The brain then, is constantly surveying its environment, and making internal calculations about what is the most cost-effective way of storing memories.

Just when you thought the brain couldn't get any better, it decides to sweep in when you need it most (when you're hungry hungry hippo), and switch to a mean surviving machine.

Hope everyone is doing great! On this week's agenda: MOH and I are going off to Comic-Con in San Diego. We've planned most of our trip, just need to finalize some last minute details.

Happy eating all!!!

* The two types of aversive memory are long term memory (LTM) and anesthesia resistant memory (ARM). LTM involves protein synthesis and involves dopaminergic neurons (MV1 and MP1 type).

Placais PY and Preat T. 2013. To favor survival under food shortage, the brain disables costly memory. Science.

Saturday, July 12, 2014

Anniversary of blog - thanks and appreciation!

I realized today that this blog has been up for one year! About a year ago, MOH and I were walking along a nature trail and the idea of a food-themed blog came to mind (thanks MOH, you're the best). The blog has evolved from highlighting the science behind food perception, to food recipes inspired by my culture, to restaurant reviews around Orange County.

I've had a beautiful love affair with food, and it's been wonderful sharing all my food ramblings, recipes, and thoughts with every one of you.

Chocolate ecstasy - souffle to die for

Whether you're reading this by chance, or tuning in on a regular basis, thanks for stopping by and supporting this blog! It may not seem like much, but seeing viewers tune into this blog has been very fulfilling - makes me feel like these thoughts and recipes are worth sharing! Sending love to everyone on this warm summer night.

Hope everyone's weekend is off to a great start! What's on my agenda for the weekend?

Easy to make tofu spring rolls with peanut hoisin sauce

Tofu spring rolls for dinner, and some amazing poke for lunch tomorrow!

Bear Flag Fishing Company - best tuna / salmon poke around (photo courtesy of MOH)
Until next time, happy eating all!!!

Sunday, June 29, 2014

Run them legs - physical activity restores function following sensory visual deprivation in mice

I finally mustered up the strength to sign up for a half marathon in Huntington Beach for 2015. It's something that I've wanted to do for a while, but have always been too scared to see if I could run the 13.1 mile distance.

Although I'm not training until roughly October, I'm trying to run a couple times a week just to keep up endurance. What's the best thing about running?

For me, it's probably running in the early morning (before the sun rises), or late evening (dark runs). Sometimes I'll wake up around 6AM, have trouble sleeping, and just roll out of bed to get ready for a run (I even have running clothes near my closet so I can make a quick getaway without fumbling in the dark).

Photo courtesy of McKay Savage
Running, or any exercise, has several physical and mental benefits. While we've heard about how an active lifestyle wards you away from sickness more frequently, stimulates higher learning capacity, and even actually increases more brain growth, what about physical exercise following an injury?

Recently, running has been shown to help mice recover visual function following visual deprivation. A study published in eLife (Kaneko and Stryker, 2014) has shown that mice with monocular deprivation have recovery of visual function following sessions of running on a treadmill while viewing visual images.* The researchers created monocular deprivation only to one eye by suturing shut one of the mouse's eyes for 30 days. As a result, very little input comes into this sutured shut eye - in fact, this simulates a condition that often happens to some children called amblyopia, or "lazy eye." Amblyopia is where vision doesn't develop normally, sometimes as a result of eyes not aligned appropriately (an issue when eyes point in different directions). Think of your eyes as requiring training for them to function at their best - if during development one eye receives more information and training than the other (this eye being the dominant eye), the eye that receives less training is often the weaker eye and sometimes not even used. For kids that have amblyopia, one of the treatments is to force the weaker eye to train itself by closing shut the more powerful eye. By shutting the more dominant eye, the hope is that the weaker eye eventually becomes strong enough to work just as well as the dominant eye.

Form of treatment for amblyopia (Photo courtesy of National Institutes of Health (NIH))
 In this study, researchers tried to see if physical activity would help speed recovery of visual function after suturing shut the eyes. Mice that had deprivation to one eye were divided into the following groups: had no post-operative treatment, were allowed to run on a spherical treadmill (I'm trying to imagine cute little running mice), viewed different images to stimulate visual training, or had exercise while looking at different images. Surprisingly, the mice had recovery of vision in their sutured eye! What was strange, however, was the recovery observed was ONLY when the mice were running and looking at different visual images - the control groups showed no visual improvement.

These findings are incredibly exciting, but running won't necessarily solve everything. It's important to keep in mind that restoration of vision in this case, happened only in the situation of combining visual stimulation with physical activity.  As in running only promotes recovery following an injury in the specific brain pathways that are activated while you're running. So for example, running would only help you recover from damage in the area important for food processing only if you are smelling or even eating something (as in stimulating your food processing pathways).

It's a bit extreme, but these findings serve more to demonstrate the remarkable flexibility of the brain to recover. Also, just think - next time you decide to get all judgmental on that person on the treadmill reading their magazine, maybe they're stimulating and increasing their brain function!

Blur of legs at the gym sweating it hard (photo courtesy of Brandon Wiggins)
Until next time, happy eating all!

*Monocular deprivation was done by shutting one eye of mouse from postnatal day 21 (within the critical period) until mice were 5 months old. Mice that had visual deprivation were then either given a treadmill alone, treadmill with visual stimulation, or visual stimulation alone. Recovery of visual function was measured using optical imaging.

Kaneko M and Stryker MP., 2014. Sensory experience during locomotion promotes recovery of function in adult visual cortex. eLife.

Sunday, June 22, 2014

Day date - food trucks

I haven't been venturing to new food sites lately, so MOH and I decided to go on a "day date" out to some food trucks that we've been eyeballing for some time. 

I love food trucks. They run rampant all over cities (there are a ton in Southern California), often tucked behind an obscure street or apartment complex, and each truck is special in its own way. Some trucks specialize only in garlic infused delights (Garlicscapes - stinky goodness but worth the bad breath, trust me), vegetarian/vegan treats (Seabirds - now a restaurant due to high popularity!), solely crepes (Crepes Bonaparte, MOH goes crazy whenever we see them at the Farmer's Market), or even Korean/Mexican cuisine (KogiBBQ - tofu burrito and calamari tacos are to DIE FOR). They combine my love for good food, quick eats, and huge creativity. You get some imaginative eats that tickle your taste buds.

This weekend, we ventured to a hotdog inspired truck (Dogzilla) and a sliders specialty truck (the Burnt Truck). 

We first started our meal with some delicious hot dogs. Dogzilla is a hot dog fusion food truck that flips the hot paradigm on its side with crazy toppings. You can find an assortment of condiments decorating each hot dog, ranging from a sunny side up egg, pizza cheese, or even Japanese seasoning furikake. I ordered the veggie Yaki Dog - a tofu based hot dog topped with yakisoba noodles (noodles, bean sprouts, cabbage, green onions), okonomi sauce, ao nori, and red ginger (bottom left). MOH got the original Dogzilla, which is a hot dog with the "traditional" Dogzilla toppings: grilled onions, avocado, Japanese mayo, homemade teriyaki sauce, furikake, and bacon bits. Served on King's Hawaiian roll buns (bottom right). The hot dogs were delicious - piping hot with just the right amount of heat, and over a sweet Hawaiian bun. I think that this place really excels in the toppings - their creative take on thinking outside the traditional ketchup/mustard/relish mix is so refreshing, not to mention tasty! And who can say no to delicious garlic fries! 

But who can say no to gourmet sliders? The Burnt Truck boasts as the first OC food truck that specializes in gourmet sliders. Run by three classically trained chefs, the Burnt Truck features a select few of classic sliders ranging from vegetarian (mozzarella), fried chicken, meatball, etc (note: their menu rotates between different types) . But the one slider that really stood out for me was their PB&J. PB&J as in peanut butter and jelly. As soon as I saw that, I knew we had to try it... and tater tots. Just because MOH and I go crazy for potato-goodness (even if we ordered fries from Dogzilla).

The slider was absolutely amazing. Very rich, but not bad for the rare splurge. With fresh bananas, homemade butter (I want to say peanuts and almonds?), and blueberry jam, this slider appeals to everyone's inner kid. Eating it brought me back to when I was a kid eating PB&Js. And the tater tots? So simple, yet it was the first thing that we finished eating before anything. 

Great meal to end a weekend-venture.

Till next time, happy eating everyone!

Saturday, June 14, 2014

Baking on a Saturday - banana-date bread

I love to eat bananas. Bananas are so great as a snack alone, topped on plain greek yogurt, munched on with a guilty scoop of peanut butter, or dipped in chocolate. But sometimes, bananas slip through the cracks. They get brown, ugly and super mushy. We don't do it on purpose, really. I try to time the bananas so I can eat the bananas prior to ripening - I try to choose varying shades of green-to-light yellow bananas to try to plan out banana eating throughout the week. But we can't help it - sometimes a banana will go ripe and brown under our watch.

What to do with ripened bananas? MOH and I like to use ripened bananas as the "butter" component of our baked desserts.

This week, I tried making a banana-date bread with no sugar (aside from sugar in the fruits, that is).

The results were great! I tried to explore the no-sugar route as an homage to my middle sister, who has enjoyed health improvements after axing sugar from her diet.

This recipe is simple and easy to do. In my sloppiness, I eyeballed the ingredients at times and everything worked out in the end!

This bread isn't overly sweet at all, as the only sources of sugar are from the bananas, dates, and blueberries. There's also a slight crunch due to walnuts.

Feel free to modify as you see fit! I'm thinking figs would be great here too.

Ingredients - makes enough for a bread loaf (modified from the following recipe):
- 2 eggs
- 2 cups of all purpose gluten free flour
- 1 cup of dried dates (roughly 6-7 Medjool dates) soaked in hot water until softened
- 2 ripened bananas
- 4 tablespoons of coconut oil
- 1/2 tsp of vanilla extract (or a squirt)
- 1/2 tsp salt
- 1 tsp baking soda
- 1/2 tsp of baking powder
- 1/4 cup of walnuts
- 1/3 cup of blueberries

Bread ingredients are extremely flexible - interested in more fruits? Try adding in other berries

1. Soak dates in hot water until softened - preheat oven to 350 degree F
2. Mash dates and bananas together until smooth mix (can use blender too if you prefer)
3. Mix eggs and coconut oil together until blended
4. Mix in flour, vanilla extract, salt, baking soda, and baking powder
5. Mix in dates/bananas to dry mix
6. Add in dry mixture with coconut oil and eggs
7. When everything mixed well, fold in blueberries and walnuts
8. Pour mix into loaf pan and bake 50 minutes in oven
9. Take out when done, and bread can be eaten right away!

Hope everyone is having a great Saturday! I finished my last class EVER for graduate school, so I'm experiencing my first weekend without any thoughts of advancement, finals, quizzes, homework! Until next time, happy eating all!

Sunday, June 8, 2014

Multi-regional appreciation of music in the brain

Appreciating music is such a universal thing. Whether it's playing one of your favorite guitar covers or serendipitously hearing your favorite song on the radio, music provides both a pleasurable and memorable experience. Think back on remembering your first school dance, your wedding song, or a song that your parents sang to you as a child.

 MOH back in the day playing the Ranard, a Thai xylophone instrument
What's going on in your brain though? Music has been shown to affect several different regions in your brain (see image below), ranging from music production (involving the motor pathway), to listening and following different beats and tones (auditory-limbic and acoustic activated vestibular pathway), and the appreciation of an amazing musical score (visceromotor system). There are quite a few brain regions in the image below, but the main idea is to just consider how many areas are turned on when you're doing something music oriented.

Different pathways involved in music processing (Koelsch, 2014)
While several different brain regions are at play during music processing, the appreciation of music is centered around four main brain regions (reviewed by Koelsch, 2014):

Amygdala (AMYG in the drawing above): the "emotional" area of the brain that reacts differently depending on the mood or tone of music.

Nucleus accumbens (NAc): also activated in response to emotional arousal when listening to music and functionally connected to the auditory region of the cortex after music listening. Ever get the "chills" when you hear a really great vocalist (like Adele)? This brain region is activated when you experience the chills, or are anticipating it. 

Hippocampus: a brain region important for memory formation. Unlike the other mentioned regions, which are activated during other "pleasurable" experiences like food intake, reward drugs, or money, the hippocampus is the only region that is activated by music pleasure. This region is activated following hearing music of varying emotions, and is also important for memory of playing music.

Getting lost in the music (photo courtesy of Jolove55)

Striatum: most recently shown to be related to having more dopamine available after hearing music (dopamine is a major hormone that affects mood and is heavily involved in reward-related behavior). This finding points to why music is so pleasurable.

While this post talks about how the brain is activated following music exposure, it's worth noting that other forms of art probably benefit similar brain regions and potentially release "good vibes" as well. If music isn't your thing, try other avenues of artistic expression (dance, painting, etc.)!

Until next time, happy eating all! Oh, stay tuned next week for a new recipe. I'm debating on trying to make pumpkin banana muffins, or quinoa "meat balls" pasta!

Koelsch, Stefan. Brain correlates of music-evoked emotions. Nature Reviews Neuroscience. 2014 Mar (15(3): 170-180.

Monday, May 26, 2014

Musings on a Monday

Ever wish you could just transform into a bird and fly towards the horizon?

I have an examination this week, so I apologize for the brief post!

Until next time, happy eating all!