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.