Tagged: fMRI
Using brain imaging to predict which vegetative patients have potential to recover
According to new research, positron emission tomography (PET), a functional brain imaging technique, is a promising tool for determining which brain damaged individuals in vegetative states have the potential to recover consciousness. This is the first time researchers have tested the accuracy of functional brain imaging for diagnosis in clinical practice.
The researchers from the University of Liége in Belgium suggest that PET imaging can reveal cognitive processes that would otherwise be hidden to traditional testing. Using imaging in addition to standard behavioral assessments could improve patients with the potential for long-term recovery.
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Temptation: The Effects of Immediate and Delayed Rewards
As we approach the loved holiday season, we also approach the dreaded weight gain that comes along with it. It probably won’t come as a surprise to you that our brain, specifically the hippocampus, plays a role in resisting immediate or delayed temptation.
The hippocampus deals with memory, including recalling past events and imagining them in the future. A study called “A Critical Role for the Hippocampus in the Valuation of Imagined Outcomes” examines healthy people as well as people with Alzheimer’s disease, which impairs memory and is associated with atrophy of the hippocampus. The study looked at “time- dependent” choices having to do with money in addition to “episodic” choices having to do with food, sports, and cultural events.
America's Stutter-free Idol
On January 17th, the talented Lazaro Arbos, a 21-year-old from Florida, went viral on Youtube for his amazing performance during his American Idol audition. The most impressive part of his beautiful voice? The fact that it was stutter-free.
During normal speech, Arbos involuntarily makes long pauses and extended vowels, using his hands to trace the words he is trying to convey. However, as soon as he starts to sing, the difficulty disappears. His new Twitter fans are calling it a divine miracle, but the phenomenon is well-known to many stutter sufferers - industry legend has it that B.B.King and Carly Simon were among them!
What's going on here? The disorder is highly varied in its presentation and severity, so science is far from a consensus about the etiology, though there have been some compelling findings. One 2003 study by Van Borsel et al. at the Ghent University Hospital in Belgium showed a marked increase in activation of the right hemisphere during speech in fMRI studies of patients with the speech disorder; more so than in normal speakers, leading to the idea that perhaps this over-activation is interfering with the fluent production of speech on the left. Specifically, a study of stutterers in Frankfurt, Germany found that activity in the right frontal operculum was negatively correlated with the severity of stuttering symptoms in patients, suggesting a compensational role. This area has been associated with timing tasks in speech in healthy controls, adding further possible significance to the specific dysfunction in verbal timing seen in stutterers.
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The Soundtrack of the Human Brain
Neuroscience researchers in China have created a method of transforming brainwaves into music by combining EEG and fMRI scans into sounds that are recognizable to human beings. The EEG adjusts the pitch and duration of a note, while the fMRI controls the intensity of the music. According to Jing Lu and his associated colleagues from the University of Electronic Science and Technology in China, this brain music, "embodies the workings of the brain as art, providing a platform for scientists and artists to work together to better understand the links between music and the human brain."
Applying EEG and fMRI data to make better music represents the limitless opportunities of the brain, potentially leading to improvements useful for research, clinical diagnosis or biofeedback therapy. In fact, researchers at the Department of Homeland Security's Science and Technology Directorate have already looked at a form of neuro-training called 'Brain Music', which uses music created from an individual's brain waves to help the individual move from an anxious state to a relaxed state.
High Definition Fiber Tracking
There are numerous brain imaging techniques that allow us to gain insight into what damage the brain may have incurred after a patient has a traumatic injury. The ever popular fMRI measures blood flow to infer neural activity. Diffusion tensor imaging (DTI) uses the magnetic properties of water to look at white matter in the brain, while positron emission tomography (PET) uses radiolabeling to look for a specific chemical in the brain. All of these are important for possible disease diagnosis, however, there is skepticism around how dependent we should be on this technology, as the results should never be taken as the absolute truth.
Comparison of X-Ray to HDFT
Now, a new type of brain imaging developed by researchers at the University of Pittsburgh allows researchers to look for connections that have been broken as a result of traumatic brain injury, much like an X-Ray allows doctors to look for broken bones. It is called High Definition Fiber Tracking (HDFT). Although the technology is not specific at the cellular level, it is accurate in observing specific connections that have been lost as a result of injury. These lost connections act as a reliable predictor for cellular information, such as the percentage of axons that have been lost.
The accompanying publication in the Journal of Neurosurgery focuses on a case study of a man who sustained severe brain damage after crashing an all-terrain vehicle (public service announcement: this is why we wear helments!!!). Initial MRI scans showed hemorrhaging in the right basal ganglia, which was confirmed by a later DTI. The patient had extreme difficulty moving the left side of his body, and it was assumed to be a result of damage to the basal ganglia. It was not until the patient had a HDFT test that doctors could pinpoint the true problem: fiber tracts innervating the motor cortex had been lost. More
Female Sexuality and Neuroscience
As feminism becomes mainstream, much of scientific research is following suit, from a book being written about female sexuality to mapping out the female orgasm in the brain.
For many feminists, this effort to better understand female sexuality can be a means of empowerment, and it is not surprising that neuroscience research has branched into this area. Many people, rightfully so, believe that to understand our body and mind we must also understand the mechanisms of behavior in the brain. Yet due to its complexity, much of neuroscience research gets misinterpreted, reduced, or even generalized when written about for the public sphere.
Naomi Wolf's Vagina: A New Biography, attempts to explain female sexuality by pulling from both subjective accounts and neuroscience to support her arguments. But what exactly does neuroscience research have to contribute to our knowledge of female sexuality? Although Wolf's attempt at writing such a boldly stated book is admirable, it fell short, especially in terms of the science. Wolf misinterprets the roles of dopamine, oxytocin and serotonin in the brain and how they could plausibly influence a female's romantic relationships.
As Maia Szalavits so eloquently wrote:
"The kind of oversimplification seen in Wolf’s book and, sadly, in many other popular accounts of neuroscience, threatens to perpetuate a psychological myth. Rather than illuminating the complex interplay between mind and body, it portrays human beings — especially women — as automatons, enslaved by brain chemicals we cannot control."
So what does neuroscience have to say about female sexuality? At last year's Society for Neuroscience Conference in Washington D.C., a 3D movie was presented of the brain during a female orgasm. Barry Komisaruk, a professor of psychology at Rutgers University, used fMRI (functional magnetic resonance imaging) to map brain activity in several women. The women were required to masturbate to an orgasm in the fMRI machine. (fMRI results are brain images reflecting activation in specific areas, and these areas are said to be lit up.) More
Internal Voices Decoded by Scientists at UC Berkeley
Researchers have developed a technique that reconstructs the words patients are thinking of that could help locked-in or comatose patients communicate.
A newly developed computer model reconstructs the sounds of words that patients think of. Over the past few years, scientists have been coming closer to being able to listen in to our thoughts. This study achieved that goal by implanting electrodes directly into patients' brains. In an earlier 2011 study, test subjects with electrodes in their brains were able to move a cursor around a screen just by thinking of different vowel sounds. Another study, conducted in September of that year by Jack Gallant at the University of California, Berkeley, was able to guess images being thought of through functional magnetic resonance imaging (fMRI).
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A Knitted Brain
Art is popular. There are many people that enjoy, support, or make a living off of art. It has the power to evoke emotion and also to allow one to express emotion through shapes, color, and patterns. Brains are popular too, but in a different sense. Everyone has a brain. Some may use it more than others, but it is something that all humans possess. This is, of course, excluding the various other life forms on earth that make use of a brain. What is not so popular is brain art. Especially brain art that is anatomically correct. The Museum of Scientifically Accurate Fabric Brain Art claims to be the largest collection of anatomically accurate representations of the brain made entirely from fabric. How exciting! The inspiration for each piece comes from dissections of the brain, functional magnetic resonance imaging (fMRI), neuroscience research, and positron emission tomography or PET (another medical imaging technique). These self-deemed "neuroartists" employ traditional art techniques such as quilting, knitting, and rug hooking to create their cranial masterpieces. Although extremely talented, these artists do warn not to use the accuracy of their art as a guide for any kind of surgical medical endeavor. More
Put Your Hands Up for Intelligence
Ever wonder why people still “talk with their hands” when they’re on the telephone? We often use hand gestures while speaking even at times when the listener cannot see them. Gestures are processed in the same areas of the brain as speech (think sign language): the left inferior frontal gyrus (Broca’s) and the posterior middle temporal gyrus (Wenicke’s area). Hand movements help us to communicate more efficiently and emphasize certain points of the message 
we are trying to convey to our conversational partners. They’re an indication of our thought process throughout the discussion. Evolutionary insight proposes that the language brain regions, which originally supported the pairing of body language and meaning, have been adapted in humans for spoken language; however, we still don’t know precisely the reason why people gesture, and more interestingly, why some people use gestures more often than others. More
Behind Closed Eyes: An Ayahuasca Experience
Ayahuasca is found to produce life-changing visions but can it also produce life-changing cures?
"As I closed my eyes, images - if they can be called such - began racing at an ever-increasing speed before me. Swirls of colors, shapes, forms, textures and sounds simply overpowered me to the point where I became immobile. Like many others before me, no doubt, I became somewhat frightened. What had I let myself in for? When I opened my eyes, the phantasmagoria of forms vanished, and I saw myself in the same room with the others"
Donald M. Topping's description is very similar to the accounts many others have given. He brought up many questions on the vividness of visions produced after his very first ingestion of the hallucinogenic brew Ayahausca. What underlying brain mechanisms allow potentially healing, uplifting and fearful experiences to occur behind closed eyelids? That is what Draulio B. de Araujo and others sought out to find. More
