DtI

Flying Through Inner Space

It’s hard to truly see the brain. I don’t mean to simply see a three-pound hunk of tissue. I mean to see it in a way that offers a deep feel for how it works. That’s not surprising, given that the human brain is made up of over 80 billion neurons, each branching out to form thousands of connections to other neurons. A drawing of those connections may just look like a tangle of yarn.

As I wrote in the February issue of National Geographic, a number of neuroscientists are charting the brain now in ways that were impossible just a few years ago. And out of these surveys, an interesting new way to look at the brain is emerging. Call it the brain fly-through. The brain fly-through only became feasible once scientists started making large-scale maps of actual neurons in actual brains. Once they had those co-ordinates in three-dimensional space, they could program a computer to glide through it. The results are strangely hypnotic.

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Magnetic resonance imaging (MRI) is a common diagnostic tool used in medicine, but MRI techniques can also be used to map the direction of water movement within tissues. Such a technique is called diffusion tensor imaging (DTI), and researchers have used DTI to study the 3D structure of the brain. Seen here are axons from neurons in a monkey brain with different directionality: red means the axon travels left to right, green front to back, and blue top to bottom. This image was collected to understand how cocaine use causes long-term changes in the brain’s structure and connectivity.

Image by John D. Olson, Paul W. Czoty, and Michelle Bell, Wake Forest University School of Medicine.

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today i was part of the AMAZING radical youth camp organized by Raices Roots Ridas with the help of tons of other amazing grassroots collectives and rad individuals. Raices Roots is offering a month long radical summer camp where youth of color in L.A are introduced to gardening, biking, healing foods, decolonial teachings, art, indigenous practices, systemic violence, resistance and much more! Folx organizing and volunteering are doing a truly grassroots work to provide REAL education to the seeds that join the camp, doing this together! i had the best time facilitating a skillshare on cycles, transitions, mxnstruation and how to support folx using a rebozo  Raices Roots, volunteers and youth are having a closing ceremony/fundraising in a couple of weeks, here is the FB event! it is inspiring to see how much our community can do/offer when we get our resources together and decide to work towards cultivating the seeds growing in this corrupt and violent concrete city.

La Loba Loca

Would you like to SUPPORT La Loba Loca’s fundraising to continue her Queer BirthWorker education? Click HERE. AWESOME PERKS FOR THOSE THAT DONATE! 

medicalxpress.com
Chinese mindfulness meditation prompts double positive punch in brain white matter

From medicalxpress:

Scientists studying the Chinese mindfulness meditation known as integrative body-mind training (IBMT) say they’ve confirmed and expanded their findings on changes in structural efficiency of white matter in the brain that can be related to positive behavioral changes in subjects practicing the technique regularly for a month.

In a paper appearing this week in the online Early Edition of the Proceedings of the National Academy of Sciences, scientists Yi-Yuan Tang and Michael Posner report improved mood changes coincided with increased axonal density – more brain-signaling connections – and an expansion of myelin, the protective fatty tissue that surrounds the axons, in the brain’s anterior cingulate region.

Deficits in activation of the anterior cingulate cortex have been associated with attention deficit disorder, dementia, depression, schizophrenia and many other disorders.

IBMT was adapted from traditional Chinese medicine in the 1990s in China, where it is practiced by thousands of people. It differs from other forms of meditation because it depends heavily on the inducement of a high degree of awareness and balance of the body, mind and environment. The meditative state is facilitated through training and trainer-group dynamics, harmony and resonance.

In 2010, research led by Tang, a visiting research professor at the University of Oregon, and Michael I. Posner, professor of psychology at the UO, first reported positive structural changes in brain connectivity, based on functional magnetic resonance imaging, that correlated to behavioral regulation. The study was done in the UO’s Robert and Beverly Lewis Center for Neuroimaging with 45 participating UO undergraduate students.

The new findings came from additional scrutiny of the 2010 study and another that involved 68 undergraduate students at China’s Dalian University of Technology. The researchers revisited data obtained from using an MRI technique known as diffusion tensor imaging. The research team found improved density of the axons involved in brain connections but no change in myelin formation after two weeks. After a month, or about 11 hours of IBMT, both increases in axon density and myelin formation were found as measured by fractional anisotropy, axial diffusivity and radial diffusivity – the important indexes for measuring the integrity of white matter fibers.

“This dynamic pattern of white matter change involving the anterior cingulate cortex, a part of the brain network related to self-regulation, could provide a means for intervention to improve or prevent mental disorders,” the authors concluded.

“When we got the results, we all got very excited because all of the other training exercises, like working-memory training or computer-based training, only have been shown to change myelination,” Tang said. “We believe these changes may be reflective of the time of training involved in IBMT. We found a different pattern of neural plasticity induced by the training.”

“This study gives us a much more detailed picture of what it is that is actually changing,” Posner said. “We did confirm the exact locations of the white-matter changes that we had found previously. And now we show that both myelination and axon density are improving. The order of changes we found may be similar to changes found during brain development in early childhood, allowing a new way to reveal how such changes might influence emotional and cognitive development.”

The improved mood changes noted in this and earlier studies are based on self-ratings of subjects based on a standard six-dimensional mood-state measure, said Tang, who is now the director of Texas Tech University’s Neuroimaging Institute and holder of the Presidential Endowed Chair in Neuroscience in TTU’s psychology department.

Tang and Posner first reported findings related to IBMT in 2007, also in PNAS. They found that doing IBMT for five days prior to a mental math test led to low levels of the stress hormone cortisol among Chinese students. The experimental group also showed lower levels of anxiety, depression, anger and fatigue than students in a relaxation control group.

In 2009 in PNAS, Tang and his Chinese colleagues, with assistance from Posner and UO psychology professor Mary K. Rothbart, found that IBMT subjects in China had increased blood flow in the right anterior cingulate cortex after receiving training for 20 minutes a day over five days. Compared with the relaxation group, IBMT subjects also had lower heart rates and skin conductance responses, increased belly breathing amplitude and decreased chest respiration rates.

“These new findings provide fundamental new insights on how the brain responds in positive ways to new inputs and reflect the excellence in cognitive neuroscience research that has defined Michael Posner’s work at the University of Oregon,” said Kimberly Andrews Espy, vice president for research and innovation. “The research by professors Posner and Tang also reflects the university’s long-running commitment to collaborate with institutions in Pacific Rim countries.”

I’m Rita Skeeter. I write for the Daily Prophet… but, of course, you all know that, don’t you?

>This is cozy.
>It’s a broom cupboard.
>Well you should feel right at home, then.

mindblog.dericbownds.net
Mechanisms of white matter changes induced by meditation.

by Deric Bownds

Diffusion tensor imaging (DTI) is a noninvasive MRI-based technique that can delineate white matter fibers in vivo, measure white matter’s structural plasticity to demonstrate that training or learning alters brain white matter. Fractional anisotropy (FA) is an important index for measuring the integrity of white matter fibers. In general, a higher FA value has been related to improved performance, and reduced FA has been found in normal aging and in neurological or psychiatric disorders. 

Just to be a little more clear, DTI is used to image the diffusion of molecules, particularly water, in the brain. FA is a measure of how directional the diffusion is at any one point. Because diffusion is directed by cell membranes, this is very useful for understanding the structure of the brain.

Posner and collaborators now show more details about changes that occur with only 4 weeks of meditation training (One suspects these changes might reverse after cessation of meditation practice?):

Using diffusion tensor imaging, several recent studies have shown that training results in changes in white matter efficiency as measured by fractional anisotropy (FA). In our work, we found that a form of mindfulness meditation, integrative body–mind training (IBMT), improved FA in areas surrounding the anterior cingulate cortex after 4-wk training more than controls given relaxation training. Reductions in radial diffusivity (RD) have been interpreted as improved myelin but reductions in axial diffusivity (AD) involve other mechanisms, such as axonal density. We now report that after 4-wk training with IBMT, both RD and AD decrease accompanied by increased FA, indicating improved efficiency of white matter involves increased myelin as well as other axonal changes. However, 2-wk IBMT reduced AD, but not RD or FA, and improved moods. Our results demonstrate the time-course of white matter neuroplasticity in short-term meditation. This dynamic pattern of white matter change involving the anterior cingulate cortex, a part of the brain network related to self-regulation, could provide a means for intervention to improve or prevent mental disorders.

Here is their description of the integrative body-mind training (IBMT) used:

IBMT involves body relaxation, mental imagery, and mindfulness training, accompanied by selected music background. Cooperation between the body and the mind is emphasized in facilitating and achieving a meditative state. The trainees concentrated on achieving a balanced state of body and mind guided by an IBMT coach and the compact disk. The method stresses no effort to control thoughts, but instead a state of restful alertness that allows a high degree of awareness of body, mind, and external instructions (5, 16, 19). RT involves the relaxing of different muscle groups over the face, head, shoulders, arms, legs, chest, back, and abdomen, guided by a tutor and compact disk. With eyes closed and in a sequential pattern, one is forced to concentrate on the sensation of relaxation, such as the feelings of warmth and heaviness. This progressive training helps the participant achieve physical and mental relaxation and calmness.

Large increases in FA were primarily observed in the corpus callosum - the bundle of nerves connecting the two brain hemispheres - and surrounding areas (ACC). In other words, meditation seems to lead to increased communication between the two hemispheres.