Meditation Saves Brains?

Finals week is upon us, and we're all fighting to cram tons of information into our noggins. It's times like these that I wish I had a photographic memory, or a ridiculously high IQ. I need a bigger brain! As it turns out, there may be a simple way to increase brain size. Results from a collaborative study by researchers from Yale, Harvard and MIT in 2005 suggested that those who meditate have increased cortical thickness in brain areas associated with attention and sensory input. The study compared individuals that meditate around forty minutes a day with those who never meditate. Those who meditated had thicker gray matter surrounding sensory and attention structures (by 4 to 8 thousandths of an inch, but every bit counts!).

These participants practice Buddhist insight meditation, in which they focus on their sensations; the noises in their environment, the air blowing through their hair, or their own breathing. They don't actually consider these stimuli, they try to block out all outside thoughts and worry only about their pure, current experience. Further analysis showed that the years spent meditating correlated directly with cortical thickness; more experienced meditators had larger brains than rookies. In some brain areas, the increased thickness was even more pronounced in older meditators than younger ones, despite the expected thinning in these regions that occurs with age.

So what does this mean? At the moment, not much of anything. Further research is required to reveal whether or not there are any cognitive or behavioral effects associated with the increased cortical thickness in those who meditate. Could meditation reverse the thinning of grey matter that comes with age? Could it turn back the neural clock, so to speak? No doubt more data on this subject will emerge in the near future.

Now if you'll excuse me, I need to go meditate. When it comes to finals, every inch of brain cortex counts!

http://news.harvard.edu/gazette/story/2006/02/meditation-found-to-increase-brain-size/

Don't I Know You From Somewhere?

Imagine you suffer a mild seizure. You take a trip to the hospital, and luckily you’re fine. Or are you? A few days later, you leave your home to walk to the local café. You see someone walking towards you that looks oddly familiar; you stop and ask them if you know them from somewhere. You don’t. Another person, looking very familiar to you, turns a corner. Suddenly you realize that everyone around you seems to be someone you know, but you can’t remember their names or where you’ve seen them before. You have a condition called Hyperfamiliarity for Faces, or HFF.

HFF is uncommon, and typically occurs following an epileptic seizure. In most cases, there are no concurrent effects, and patients seem perfectly healthy. It is not a permanent condition, but has been shown to last anywhere from a few seconds to several years. A review by Devinsky and colleagues in 2010 pooled all available information on HFF, including case studies and data from imaging research. They point to a miscommunication between the fusiform face area and the structures involved in autobiographical and episodic memory. Lesions are typically within the left hemisphere and temporal lobe. Devinsky and colleagues also explored research on déjà vu. They view déjà vu as another form of Hyperfamiliarity, but for experiences instead of faces. Seizures stimulating the amygdala, hippocampus, and perirhinal cortex have been implicated in the déjà vu experience. There is also evidence for hyperexcitability in the right hemisphere. Perhaps, in individuals with HFF, damage to the left hemisphere requires the right hemisphere to become overactive in an attempt to restore complete functionality. Devinsky et al. summarize that “HFF may be produced by impaired left hemisphere identification of unique facial features and excessive right hemisphere processes that link individual faces with emotional and personal meaning, leading to spurious familiarity feelings. Left temporal lobe dysfunction may impair novelty signaling and detection of specific facial features while disinhibiting right temporal regions that falsely signal familiarity.”

Pretty interesting stuff! It’s hard to imagine living with HFF. What about watching a movie, or your favorite TV show? Would you get an overwhelming feeling that Angelina Jolie and Johnny Depp were pals from your past? Would the people that you actually know stand out in a sea of familiar faces? Could this be an unknown cause for uncomfortably friendly personality types (Mr. Rogers)? Thoughts to ponder!

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2848104/?tool=pmcentrez#__sec7

Trippin' on Tryptophan

Turkey and its associated essential amino acid L-tryptophan have long been blamed for the inevitable lethargy that follows the Thanksgiving meal. Does turkey really deserve this reputation? Not so much. L-tryptophan can be metabolized into serotonin and melatonin, which would explain the sleepy after-effect. However, the relatively low levels of L-tryptophan in turkey will typically cause drowsiness only when consumed on an empty stomach. When’s the last time you saw a family member sit down to a big plate of turkey (and nothing else) on Thanksgiving?

So what’s really causing ‘the itis?’ More than likely, it’s the carbo load associated with the Turkey Day meal. Stuffing, roles, mashed potatoes, pie...the list goes on. When we consume a ton of carbohydrates, insulin is secreted by the pancreas, forcing amino acids that would typically compete with tryptophan to move from the bloodstream to muscle cells. L-tryptophan can then be synthesized into serotonin and melatonin, inducing that naptime feeling.

Some more possible causes? Any time you eat a large meal, your body’s blood supply will flow away from the brain and towards the digestive system. Your energy reserves will take a serious hit as your body works hard to digest a feast. Let’s not forget booze. In my family, jell-o shots and beer are equally as essential as cranberry sauce or green bean casserole to the traditional meal. Alcohol acts as a sedative, enhancing the effects of the overall meal.

And let’s be honest, some of us are looking for any excuse to catch up on some z’s. Happy napping,
all!

http://chemistry.about.com/od/holidaysseasons/a/tiredturkey.htm

Celebrating Uncertainty

Watch this video! But it’s so long, I know. Do it anyway! Because not only are optical illusions fun, but you’re probably going to learn a thing or two about perception and the human experience.


We've all seen optical illusions before. A typical response is something like "Wow...I guess my senses are tricking me; I guess I know less about my surroundings than I thought." Lotto does something truly profound with optical illusions. He appreciates the gaps between reality and our own perceptions, he sees these inconsistencies as windows into the brain and its functioning. As he explains, “context is everything.” Our awareness of the physical world is limited by our perception, a system that we know can be fooled. According to Lotto, there’s nothing wrong with the inaccuracies in our perception, they’re proof of the patterns in the world on which we base our experience. If humans weren’t able to transform the overwhelming amount of stimuli invading our sensory organs into a concise representation, we wouldn’t be able to function. Lotto explores how our experience-based expectations can be modified and combined. He looks at optical illusions in other species, something I had never considered before. He also explains how one sensory modality can be transformed into another, without a loss of understanding. Fascinating stuff! I don’t know about you, but I’ll be paying a little more attention to my perceptions from now on.

Who Needs Accurate Memories, Anyway?

Last year, Cambridge researchers stumbled across some revealing data on false memories. They were studying the effects of brain damage on memory in rats. Rats were presented with a small, elaborate object and given time to become familiar with its appearance. They were then placed in a normal cage environment, free of wacky objects, for an hour. When presented with the same object as before as well as a new object, rats without brain damage spent significantly more time exploring the new object, ignoring the one they’d seen an hour before. The researchers expected that rats with damage to the perirhinal cortex (involved in visual memory consolidation) would show no preference towards the previously shown object. The brain damaged rats took this hypothesis a step further. They actually spent LESS time investigating the new object than the normal rats, implying they had some sort of familiarity with the object, despite having never seen it before.
 

These findings propelled the research team into a new focus. They wondered if the stimuli in their regular holding environment, coupled with perirhinal damage, resulted in formation of false memories. To test this theory, a similar method was used, but rats were raised in a dark room, devoid of visual input. The visually impaired rats acted as the researchers had initially expected for rats raised in lit cages, supporting their hypothesis.

So what’s going on here? The perirhinal cortex is easily harmed in comparison to other brain areas. Damage to this area is common in diseases classified by memory impairment, such as Alzheimer’s. As it turns out, individuals with these impairments actually perform better on tests of memory if they’ve been in a dark, low-stimulus environment before testing. Connections, connections! According to the Cambridge researcher Lisa Saksida, the perirhinal cortex is responsible for formation of complex visual memories. When the area is damaged, less specialized regions will attempt to recreate memories using generalized environmental stimuli. This disadvantaged form of memory reformation produces what we know as false memories. Could the perirhinal cortex also be involved in sensations of déjà vu? Flashbulb memories? Who knows! I look forward to seeing more research emerge on this subject.

The original article can be found here: http://www.sciencemag.org/content/330/6009/1408.abstract

Cocaine and Cupcakes, One in the Same?

While home in Minneapolis this past weekend, I took some time to catch up on recent Star Tribune articles. I came across the intriguing title, “Some foods as addictive as cocaine?” Apparently, 28 papers on food addiction have been published in this year alone, according to the National Library of Medicine. This is a hot topic, and the food and beverage industry is nervous. Researchers are picking apart the brains of food addicts and obese individuals to understand what makes them addicted to food. It is becoming clearer and clearer that the delicious beverages and foods we love can “hijack the brain in ways that resemble addictions to cocaine, nicotine and other drugs.”

Like me, you may be thinking to yourself “well, duh.” The human body has not evolved for the abundant, sugary, fatty foods common to American culture. The foods we tend to love most are also those that are the worst for us (fries dipped in ice cream, anyone?). Sugars and fats were rare in the hunter-gatherer’s environment, and they taste so great because of evolutionary pressures to search long and hard for them. When you only have access to fats and sugars once in a while, an affinity for them becomes essential for survival. Aside from searching the aisles for the items on our grocery list each week, we don’t do much hunting or gathering these days. The well-liked flavors that once helped us prosper are now killing us. As it turns out, not everyone appreciates this, which is why so many researchers are looking at the mechanisms behind food addiction. They need factual collateral to help the general public understand the ways in which food can modify their brains.

A widespread knowledge that food interacts with the brain in ways similar to that of lethal, illegal drugs could change the way we eat. This idea is frightening for the food and beverage industry, which the Trib article points out, is worth at least one TRILLION dollars. Though there is overwhelming evidence for the addictive nature of certain foods, “food company executives and lobbyists say nothing has been proven.” Ha! We can only hope that one of these days, the CEO of Frito-Lay will wake up in a cold sweat, fiending for his next potato chip fix, and think to himself “What have I done!?” Until then, it’s important to understand that food isn’t just sustenance. It can also be viewed as a delicious, fatty, drug.

Read the original Star Tribune article here: http://www.startribune.com/lifestyle/wellness/133302438.html

No Brain Wave Is Safe

UC Berkeley researchers have recently undertaken a project (see www.nbcbayarea.com/news/tech/Brain-Scanner-Records-Dreams-on-Video-130497213.html) that is both fascinating and incredibly creepy (perfect for a Halloween post!). They utilized fMRI technology to create a visual response database. By showing participants an array of videos, and simultaneously recording brain activity, they collected a cornucopia of data on how the human brain responds to specific visual stimuli. The database allows them to (more or less) reconstruct an image that a subject in an fMRI machine is simply imagining. This means (hypothetically) that if you are sitting in this fMRI machine, and an inappropriate visual memory pops into your head, BOOM. They've caught you, they saw it on their own computer screen. The database has outed your private thoughts. The system is far from perfect, as this video makes clear:



But within a decade or two, as the system is improved, this technology could have some pretty serious implications. We could see what people are dreaming, dive into the subconscious. Revealing, previously unavailable data would become available to numerous research areas. For example, flashbulb memories could be reconstructed on screen, then compared with actual happenings. There is, of course, the terrifying thought of the government getting their hands on this system and going on a brain invasion spree. Let's take a moment to appreciate the premature nature of this technology. Our thoughts are safe...for now.

The Wild World of Mirror Neurons

I think mirror neurons, which provide the connection between the actions of others and our own movements, are the coolest thing...ever. They are essential for empathy, imitation, appreciation of facial expressions, and awareness of body language. V.S. Ramachandran, who has studied mirror neurons extensively, sums up their importance very nicely in this video...



Couldn't have said it better myself! The sudden existance of mirror neurons, and their following adaptations, were an essential part of mammalian evolution. They allowed us to learn from the techniques and emotions of others. As Ramachandran says, they allowed for a "Lamarckian" passing of knowledge, which then allowed for unique cultures. Human existence is completely dependent on these beautiful little neurons. What's most interesting is that by anaesthetizing the skin, we can remove the barrier between our own and others' actions (this is also common in those with mirror-touch synesthesia). We should really be devoting more attention to the role and mechanisms of these neurons, where's the research!? Give me more!

I've Got a Funny Feeling

I’ve blogged recently about both synesthesia, the cross-wiring of the senses, and empathy. As it turns out, there has been research connecting the two. A 2007 study by Michael Banissy and Jamie Ward utilized the unique properties of the synesthetic brain to explore the spectrum of empathic ability. These particular synesthetes have mirror-touch synesthesia, in which observations of physical touch on others elicit a tactile response on one’s own body. Participants were shown another individual being touched on the cheeks and hands, but told to ignore them. They were simultaneously being touched in the same regions and reporting their tactile experience. A control group of non-synesthetes were included for comparison.

What’s interesting about the responses of synesthetic individuals is the variation in their mirrored tactile reactions. For instance, when synesthetes viewed someone being touched on the right cheek, some of them reported feelings on the right cheek, others on the left, and to various extremes. This is typical in studies of synesthetes; it’s also what complicates research in this area. Synesthesia appears in numerous forms, across differing sensory pathways. The experience is slightly variable for each affected individual. For instance, for those who associate numbers and letters with specific colors, color matches vary greatly. Also, some report actually viewing letters/numbers in color, while others are simply aware that they are associated with color.

So how did the synesthetes perform on these tactile response tasks? They reported a significantly higher number of mirror touch errors than controls, meaning they weren’t distinguishing as well between synesthetic response to the touch of another and the feeling of being touched.  However, their response time was faster than that of controls when personal touch matched that of the other individual. Banissy and Ward conclude that empathy is multifaceted, and that these synesthetes are higher than non-synesthetes in emotional reactivity, but not in other areas (social skills, cognitive empathy). The data supports the idea that empathy is dependent upon shared interpersonal experience.

Original article: http://daysyn.com/Banissy_Wardpublished.pdf

Cry Me a River (Or Not)

I’ve been researching the neural mechanisms involved in empathy lately. There are numerous theories on the pathways involved in producing an empathetic response. I came across an article I found especially intriguing. To study deficits in empathy, we typically look at individuals on the autism spectrum. Evidence from these types of studies can only tell us so much, considering the vast range in the levels of social and emotional disabilities involved. An autistic person lacking the mechanistic ability to empathize would also have trouble learning to “fake” an empathetic response, as this would require them to cue into social norms. So, can empathy be learned?

A 2009 study by Danzinger, Faillenot and Peyron sought the answer. They used fMRI technology on a group of subjects suffering from congenital insensitivity to pain. If these individuals couldn’t feel pain themselves, could they still empathize with those that do? Or is the production of an emotional mirroring founded on personal experience and memory? Subjects were shown images of both faces showing painful expressions (to test emotional response) and body parts in painful situations (to test somatosensory response). fMRI scans reported activity in response to these images in comparison with control, non-painful images. Participants were also given a self-reporting empathy survey.

The subjects with congenital insensitivity to pain rated themselves at typical levels of empathy compared with a normal, healthy population. fMRI results revealed that activity in response to facial expressions was generally normal, but represented a distinctly different network of involved structures. Responses to images of body parts in pain were significantly lower than average. Danzinger, Faillenot and Peyron determined that the pathways used by CIP individuals to produce empathy reflected a learning process. Some areas, namely the insula and mid-cingulate cortex, were stimulated in both CIP and non-CIP brains when shown stimuli. Activity seen in the ventromedial prefrontal  and ventral posterior cingulate cortices of CIP subjects only points to the role of association mechanisms. These mechanisms are likely based on what is socially expected when faced with the emotional or physical pain of others.

This study is intriguing, and leaves much to be explored. To what extent are we hard-wired for empathy, and how much of it is learned? How do the pathways for emotional and somatosensory empathetic pathways diverge and converge? I can only hope that by March (when I have to present on this very topic), I have the answer to these and other fascinating questions.

PDF for the original article can be located here: http://www.empathogens.com/empathy/cip-empathy.pdf

A Parasite That Lets Tom Kill Jerry

Sitting around the campfire as a young girl, my dad would always tell a story about brain-infesting, evil-doing parasites. As much as I would like to believe that this was only a scary story, at least half of the human population is infected with some form of parasite of the brain or body. One that is especially creepy and strange is Toxoplasma gondii. This parasite has been studied in depth recently for its strange effect on the rat population.

A rat infected with T. gondii behaves completely normally…except for one small behavioral detail. Rats, which rightfully fear cats, are highly sensitive to their urine, keeping clear of it whenever possible. T. gondii causes rats to become ATTRACTED to cat urine, therefore severely decreasing their chance of dodging kitty predators. This parasite, when it attacks the brain, is found in high concentrations in the amygdala. This begins to explain modifications to innately feared stimuli. Weird, huh?

What’s even weirder about this parasite is its link to schizophrenia. Schizophrenics are much more likely to show presence of T. gondii in the brain than normal, healthy people. Women infected with the parasite are also more likely to have children that eventually develop schizophrenia. When given Haloperidol, a drug used to treat symptoms of schizophrenia, the urine-crazed rats reversed their behavior and became “normal” again. Could the life cycle of these parasites shed light on the origin of schizophrenia? Perhaps get us closer to a cure? Perhaps! I hope to see more research on this unique, campfire story-worthy parasite.

For more information, see: http://www.livescience.com/7019-mind-control-parasites.html

Your Voice Tastes Like Maple Syrup

During my senior year of high school, I enrolled in a Theory of Knowledge class. During one uncharacteristic class period, we discussed something of interest to me. Mr. Case explained that there are some people whose senses are crossed, combined, or layered. A classmate raised her hand with a frightened look on her face. She asked the class, “doesn’t everyone taste sounds?” She had no idea she was a synesthete. I’ve been fascinated ever since.

Synesthesia results from crossactivation of brain regions associated with sensation. Synesthetes have been reported with every sensory combination imaginable. They see music. They hear touch. THEY HAVE SMELL-O-VISION! A student speaker/synesthete in my college biological psychology class (boldly) explained that upon orgasm, every one of her senses fires rapidly, ricocheting off of another; a symphony of sight, touch, taste, smell and sound overcoming her. Oh. My.

Considering that 1 in 2000 individuals experiences some sort of synesthesia (Baron-Cohen et al., 1996), and that we’ve been studying the condition for over one hundred years (Galton 1880a), we know a lot about it, right? Nope. No one seems to know for certain when or why this happens. The big issue in untangling synesthesia is that it occurs in so many sensory combinations, then along a spectrum within each combination. Not to mention most synesthetes are unaware of their condition. Think about it: if you were born without the ability to taste, would you question it? If you saw colors associated with letters from the time you were born, you’d believe that’s the way the world works. The unique nature of synesthesia makes it very difficult to examine. The vast amount of research on the subject is therefore highly inconclusive.

But let’s take a break from being so sciency and bask in how COOL this is! Synesthetes and those who study them almost always see the condition as an enhancement to their lives. They can outperform most on related cognitive tasks (like picking out a 2 in a sea of 5’s…because it’s a different color), and they get to experience the environment in a way most can never understand. It seems to me that synesthesia may actually be a fossil of neuroevolution. Perhaps our ancestors experienced sensory input as a web, a combination of what we consider to be separate functions. Over time, in order to conserve energy, our sensations and perceptions became simplified. Then again, these people may represent “the brain of the future.” Who knows? I look forward to the bevy of research that is sure to come.

F. Galton, Visualised numerals. Nature, 21 (1880), pp. 252–256.

S. Baron-Cohen, L. Burt, F. Smith-Laittan, J. Harrison and P. Bolton, Synaesthesia: prevalence and familiality. Perception, 25 (1996), pp. 1073–1079. (1880), pp. 252–256.

fMRI: The New and Improved Lie Detector Test

I've been reading a lot lately about the potential use of fMRI scanning in court trials. For the most part, neuroscientists do not support use of the technology as it currently stands. This hasn't stopped numerous individuals from trying to incorporate fMRI scans into their supporting evidence. Defense attorneys in a 2009 San Diego child abuse case attempted to incorporate fMRI evidence, later denied by the judge. (http://www.wired.com/wiredscience/2009/03/noliemri/) The company that performed the testing, No Lie MRI, claims its data is 90% accurate, much more convincing than a standard polygraph test. No Lie and similar companies base their testing on the idea that the ventrolateral area of the prefrontal cortex is the tell-all for fibbing. Basically, heightened blood flow to this area during questioning indicates that the participant is a dirty, rotten liar.

In 2010, a neuroscience researcher named Kent Kiehl became involved in the trial of a serial murderer named Brian Dugan. (http://www.nature.com/news/2010/100317/full/464340a.html) Dugan had already served twenty years in prison, but was appealing to the court to do away with his death penalty charge. Kiehl used fMRI evidence to show that Dugan was suffering from severe psychopathy; he couldn’t possibly have made clear decisions about murderous acts with a mind so ‘handicapped.’ Though this evidence was allowed in court, the death penalty charge remained unchanged.

How should we feel about the use of this invasive technology? fMRI can visualize the interworking of our brains, completely out of our own control. With enough practice, you can fib on a lie detector test (people do it on Maury all the time). But can you lie to an fMRI scanner? Is this any different from more generalized rights to privacy? fMRI lie detection is a growing industry, with new companies spurting up annually. It doesn’t seem that the current technology can back up promises these companies are making, but what if it could in the future? Should this sort of technique, if based on sound evidence, be considered ethically sound? I think not. Our minds are the only possession that is truly our own. It is our choice who to let in, how to manipulate what emerges. If we take that right away (even from murderous, terrible people), what do we have left? One day, you could show up at a job interview only to be thrown into an fMRI and analyzed by a representative from No Lie MRI. This is a slippery slope, and I foresee some heavy controversy in the near future.

The Human Camera

Are you ready for your mind to be blown??! Get ready…here it comes…

This man, Stephen Wiltshire, has an astounding memory. He is also a quick-moving, gifted artist. His incredible talents are especially intriguing seeing as his autism, by generalized standards, should leave him with deficits in spatial working memory. Stephen obviously has a brain that is very unique. This calls to question, again, what does it truly mean to be intelligent? I could spend the rest of my life working to enhance my mental capacity and improve my drawing skills, but I could never, ever draw Rome so beautifully from memory (or while looking at a photograph, for that matter). I might carry a conversation or acknowledge social cues better than Stephen, but doesn’t that just make us intelligent in different ways?

Savant syndrome is not uncommon in the autistic population. According to Dr. Darold Treffert, one in ten autistic individuals displays this trait. He points to a theory developed by Allan Snyder which states that magnetic pulses directed towards the left hemisphere can increase activity in the otherwise hushed right brain mechanisms. This occurs in those without autism when the left anterior temporal lobe is inhibited. Increased action in the right brain explains increased talents in visual memory, music and the arts.

I wonder, is it always better to have a “normal, healthy” brain, or do savants like Stephen Wiltshire have something to teach us about so-called intelligence?

If Loving the Internet is Wrong, I Don't Want to Be Right

I recently read an article, originally published in The Atlantic, about the so-called “Googlization” of our brains. The fast-paced wonderland of the web provides us with a wealth of knowledge, easily accessible by a few clicks. But are there repercussions that come with such ease of access? Is the internet letting our brains off the hook? According to Nicholas Carr, our brains are rewiring in response to the way the internet is organized. We are becoming less patient, less capable of deep thought or extensive reading. This ironically lengthy article brought forth some very interesting points, some of which I thought applied nicely to our in-class discussion on intelligence.

As Carr points out, reading is not instinctive like the desire for speech. Children innately begin to speak; the importance of communication is ingrained into our evolutionary history. As our need for communication expanded, written word became increasingly important. The web has taken this aspect of our culture to another level. Nowadays, we expect most of what we read online to be succinct. We tweet, update our statuses, and read abstracts or blogs instead of lying down with a good book. Newspapers and magazines are beginning to mirror this transition as well. Is all of this good for our brains?

It seems as though our access to the internet has made life a heck of a lot easier. It could be argued that we’ve become lazy, and so have our brains. I disagree. Human intelligence should not be defined in the sense that we would define a computer’s capacity. My laptop can store four gigabytes of information, but can it learn from its environment, pulling together stimuli in order to survive and flourish? If we are learning to take advantage of the ease of access found on the web, good for us. We’re evolving; we’re making space in our noggins for other activities. I may depend on Google for facts I could easily remember, and I may be too accustomed to the concise nature of online communication, but I’m proud to be a child of the technological age.

Carr's original article can be found here: http://www.theatlantic.com/magazine/archive/2008/07/is-google-making-us-stupid/6868/.