How Your Brain is Like a City

Image credit: Van Wedeen, M.D., Martinos Center and Dept. of Radiology, Massachusetts General Hospital and Harvard University Medical School

The link between the two isn’t metaphorical in this case- according to a new study, the connective foundations of our brain look as though they were designed by a grid-focused city planner.

Researchers used cutting-edge imaging technology to look at places where the fibers that carry messages from one part of the brain to another intersect. And they found a remarkably organized three-dimensional grid, according to Van Wedeen of Harvard Medical School, the study’s lead author.

The grid is a bit like Manhattan, Wedeen says, “with streets running in two dimensions and then the elevators in the buildings in the third dimension.”

Obviously this brain-city would not fit on a single plane- the human brain has many folds and curves. So, Wedeen says, “you have to imagine Manhattan bent into some odd shapes. But the underlying grid doesn’t change. The streets intersect at 90-degree angles and the buildings rise vertically.”

It sounds to me like that brain is less like Manhattan, and more like the city pictured during this famous scene from Inception:

This city-like grid represents a significant shift from the traditional model of the brain’s wiring. Wedeen explains that in the old view, “the brain looked somewhat like a plate of spaghetti or perhaps like one of those old antique telephone switchboards with a million wires running more or less at random.”

This new model for understanding the internal structure of the brain may help to explain how a relatively small number of genes contain the blueprint for something as complex as the human brain- a question that has stumped geneticists for years.

The answer may be that in a highly organized grid system with consistent rules, a genetic blueprint doesn’t have to describe every detail of the final product, Wedeen says. “The grid system would allow a species to gradually add new functions to its brain much the way an architect adds extra floors to a building or a city planner adds new streets.”

There remains some uncertainty regarding whether the entire brain is actually laid out in this way. Weeden was only able to resolve the grid for about a quarter of the human brain, mostly in the deepest parts. Some researchers have expressed the opinion that their model is oversimplified, or that while the grid may exist, it is combined with other, crisscrossing connections as well.

The debate may be resolved within 5 years- that is the timetable for the US National Institute of Health’s Human Connectome Project, which aims to map all the brain’s wiring and demonstrate its connection to mental health over the next half-decade.

Sources:  Research abstract: “The Geometric Structure of the Brain Fiber Pathways” - Science Magazine

Press release: “Brain Wiring a No-Brainer?” 

The Human Connectome Project

Theta Wave Activity Linked to Improved Memory Recall

If you think about it, you probably feel as though you have both good and bad memory days- maybe even hours. I like to think that my memory is pretty strong as a general rule, but there are periods of time where I’m just drawing blanks. There’s a whole host of reasons for these variations. After all, it’s not as though every person is born with a “memory score” that permenantly determines their ability to recall information. Like everything related to our minds, it’s far more intricate than that.

New findings from a prestigious center of neuroscience are demonstrating the significant relationship between levels of theta brain wave activity and our ability to remember at that moment in time. A paper describing this work, from scientists at UC Davis, was recently published in the journal Proceedings of the National Academy of Sciences.

To prove their case, professors and graduate students measured theta wave oscillations in the brains of volunteers during a memory test. Volunteers were asked to memorize a series of words. They later had to recall whether they had seen the word previously, and the context in which the word was seen. Volunteers who were experiencing higher levels of theta wave activity right before they were asked to remember an item were more likely to remember correctly.

Memory recall improved only when volunteers had high theta activity before they heard the cues. If it had been the case that theta activity had increased only after the cues were given, this study would instead suggest that theta waves were stimulated by the cues themselves—perhaps an indicator that the brain was processing a new challenge. But that was not the outcome here. Subjects whose brains were in a high-theta state were essentially “primed” to do better on the memory test once it started.

Of course, this should not be taken to mean that high levels of theta activity are the only factor behind successful memory recollection, but the study does lend support to the idea that everyday memory ability is just as much as a reflection of what’s going on inside the mind as the context outside of it.

“The work goes against the assumption that the brain is waiting to react to the external world. In fact, most of the brain is busy with internal activity that is not related to the outside world — and when external stimuli come in, they interact with these spontaneous patterns of activity.”

- Charan Ranganath, Professor, UC Davis Center for Neuroscience

In this study, the researchers did not actually attempt to stimulate theta activity- they were merely measuring it and recording results. Their hope is that research could lead to treatments for memory loss. Ideally, audio visual stimulation methods to increase theta activity will be part of the dialogue as this research moves forward.

Source: University of California

Emotion revealing itself to researchers…

http://www.inderscience.com/search/index.php?action=record&rec_id=22645

This abstract points to a great example of the work being done to verify what AVS/Entrainment enthusiasts already know – that emotions, brain rhythms and audio-visual stimulation are usefully inter-related.

When looking for answers that apply to people in general, statistical science has a lot to offer – it’s nice knowing that what you think is happening with your sessions has a sound underlying mechanism. On the other hand, once you become familiar with your own personal responses, emotion/stimulus correspondences much better than “the average recognition rate of 56.66% and 66.67%” can be routinely achieved, i.e. knowing what your own EEG typically looks like, you will be able to tell a lot more about yourself than you could with a “blind” EEG, and you will quickly be able to predict your own response to a particular stimulus.

Abstracts like this are a goldmine for session developers – tantalising snippets just begging to be incorporated into AVS sessions.

With such safety and simplicity, it’s easy to underestimate what can be achieved with sound and light.

Cheers,
Craig

Neuroplastic changes found following brainwave training

A user just sent me a link to an exciting new study outlined in Science Daily about brainwave training resulting in changes in brain plasticity (or the ability of the brain to adapt to change):

Significant changes in brain plasticity have been observed following alpha brainwave training.

A pioneering collaboration between two laboratories from the University of London has provided the first evidence of neuroplastic changes occurring directly after natural brainwave training. Researchers from Goldsmiths and the Institute of Neurology have demonstrated that half an hour of voluntary control of brain rhythms is sufficient to induce a lasting shift in cortical excitability and intracortical function.

http://www.sciencedaily.com/releases/2010/03/100310114936.htm

40 Hz and Consciousness

A new study looks at the significance of gamma waves in consciousness. Gamma has for some time been suspected as being an important band for self-awareness and other aspects of consciousness – 40 hz in particular. This study refines that thought.

Here’s the abstract: http://cercor.oxfordjournals.org/cgi/content/abstract/19/8/1896

What makes us become aware? A popular hypothesis is that if cortical neurons fire in synchrony at a certain frequency band (gamma), we become aware of what they are representing.

…we also observed increases in gamma band ERS within the amygdala, visual, prefrontal, parietal, and posterior cingulate cortices to emotional relative to neutral stimuli, irrespective of their availability to conscious access. This suggests that increased gamma band ERS is related to, but not sufficient for, consciousness.

What Gamma Can Do For You

For a long time neuroscientists have shown work from poor unsuspecting birds and cats that there are specific critical periods in development important for a functional visual system or a species-appropriate bird song. In humans there have been a few unfortunate cases of horrific neglect of children (i.e. Genie) that have likely been responsible for profound intellectual deficits, which have been informative to scientists interested in the consequences of depravation during the early years. But scientists have not been able to conduct a formal and yet ethical scientific experiment to measure the relationship between a critical period and its function in humans until now, thanks to the ability to measure gamma.

On Oct 21st, the Science Daily featured an article on the exploration of the critical period for language development and other skills in toddlers by measuring their gamma waves on the EEG. The time period between 16 to 36 months is a time of tremendous language growth in humans, where their vocabulary typically expands from about 100 to 1000 words. Dr. April Benasich from Rutgers University in Newark, measured gamma activity in the frontal cortex of toddlers (16, 24 and 36 months) while they sat on a parent’s lap and quietly played. Gamma power (which is determined by the amount of synchronous gamma firing) was associated with language development, cognitive skills, behavior and impulse control. The more advanced a child’s language or cognitive skills, the more gamma power that child showed. And as expected, children who’s parents had a history of language impairments showed lower gamma power.

This new finding is consistent with what is already known about gamma in adults and from work in animals. Gamma heightens during the processing of linguistic information, during the formation of ideas and memories and during other abilities. Furthermore, gamma fires between 2 regions of the brain during associative learning, when a new concept is linked to one already known.

Low gamma coherence within different hemispheres is associated with ADD and learning disabilities. In fact Dr. C. Njiokiktjien from the Amsterdam, Netherlands compared intrahemispheric coherences of various frequencies (including gamma) of children with non-verbal vs. verbal learning disabilities(1). Their results suggested that children with non-verbal learning disabilities had less connectivity in the right hemisphere, which is consistent with the idea that it’s the right hemisphere that manages spatial skills, as well as other non-verbal tasks.

Dr. Hermann from Magdeburg University in Germany presents a model of gamma based on its power under various psychiatric conditions(2). Too much gamma firing is associated with ADHD, positive associations in Schizophrenia (i.e. hallucinations) and epilepsy, and Alzheimer’s disease, negative symptoms of Schizophrenia (i.e. blunt or flat affects) are associated with too little gamma.

So can we benefit from using brainwave entrainment to help us enter gamma states? Or are there risks associated with having more gamma power?

Dr. R. Olmstead, a clinical psychologist from Sunrise, FL, found benefits with gamma training in children with non-verbal learning disabilities, ages 6-16(3). She exposed them to 35 min brainwave entrainment sessions twice a week for 6 weeks. The sessions alternated between excitatory sessions (increasing from 14 (beta) to 40 (gamma) Hz), and inhibitory sessions (decreasing from 40 to 14 Hz). She found that her training enhanced various non-verbal cognitive abilities such as processing speed, freedom from distractibility, arithmetic and coding.

But what about the rest of us?

I think there is good reason to hypothesize that gamma training might also benefit many with other learning disabilities as well. But I am concerned about the fact that ADHD is associated with too much gamma firing. Thus if you have a learning disability and ADHD, or just ADHD alone, or even if you didn’t have any signs of ADHD, would gamma training enhance your distractibility or impulsiveness? 

Unfortunately, there hasn’t been enough research done to answer these questions at this point. However, there is good news. Brainwave entrainment for most of the population is a very gentle stimulus, and it takes time for cognitive benefits to take effect. Thus training with gamma (or any other stimulus) is done slowly. All such training should be conducted mindfully, and if you start to develop any unwanted symptoms, you can simply stop your training, and the effects will likely to go away. The higher the gamma power, the more severe the symptoms, so ignoring milder unwanted side effects could be dangerous.

The study by Olmstead might also be a good example as to how to safely train gamma. She trained students to progress into gamma with the excitatory protocol, and to leave gamma and return to beta in the inhibitory protocol. I would imagine that such training is good for leading our brains in and out of gamma as needed. And thus it might be teaching our brains to self regulate.

Nevertheless, there is an element of adventure in using gamma to potentially enhance your cognitive skills, and if the idea makes you queasy, I’d stand back and wait for more research to be done.

References:
1 Njiokiktjien C, de Rijke W, Jonkman EJ. Children with non-verbal learning disabilities (NLD): coherence values in the resting state may reflect hypofunctional long distance connections in the right hemisphere. Fiziologiia cheloveka. 2001; 27: 17-22.
2 Herrmann CS, Demiralp T. Human EEG gamma oscillations in neuropsychiatric disorders. Clin Neurophysiol. 2005; 116: 2719-33.
3 Olmstead R. Use of Auditory and Visual Stimulation to Improve Cognitive Abilities in Learning-Disabled Children. Journal of Neurotherapy. 2005; 9: 49-61.

New study on Brainwave Entrainment (By Dr. Huang)

I’m pleased to announce the publication of “A Comprehensive Review of the Psychological Effects of Brainwave Entrainment” in Alternative Therapies in Health and Medicine this month. This paper is the most comprehensive review of peer reviewed research in the subject, and was written in order to inform those within and the beyond the field of brainwave entrainment (BWE), and to provide sufficient background for future research.

Most of the research known to date has been summarized by David Siever in two unpublished manuscripts that he sells and distributes. They contain much valuable information about the history of BWE, both published and unpublished studies and proposed mechanisms of action. However, despite their length, they do not provide a complete listing of the peer reviewed literature, nor have his manuscripts faced the scientific scrutiny that comes with publishing in a peer reviewed journal. In fact, in our comprehensive search, we found articles that have never before been mentioned by those in the brainwave entrainment development and scientific community. Why? Believe it or not, the problem is in the inconsistency in terminology used to describe BWE. The term, BWE, until today, cannot be found in the scientific literature. Instead it is referred to as audiovisual stimulation, photic stimulation, photic driving, auditory entrainment, etc, etc. In all I did a search using 31 different terms to look for articles on brainwave entrainment, which returned 27,830 articles using Ovid (1 out of the 4 databases I used to do the search). Only a very small handful of these turned out to be articles on BWE. Thus much of the credit needs to go to my bosses at Transparent Corporation, who gave me the time to do this exhaustive, time consuming, and yet important work.

I looked for papers with psychological terms that described outcomes that I’d seen associated with BWE on the web, in conferences and in the published and unpublished literature. After combining the two searches, and screening for those that were indeed articles addressing psychological outcomes of BWE, and those that passed some basic scientific criteria, we ended up with just 20 articles.

The psychological effects that had been examined in relation to BWE included cognitive functioning (we divided it into verbal, non-verbal, memory, attention and overall intelligence), stress (long and short-term), pain, headache/migraines, mood, behavior and pre-menstrual syndrome (PMS). When two or more studies had examined similar outcomes, we placed them into tables for greater comparability. Thus we had five tables divided by cognitive functioning, stress, pain, headaches/migraines and mood. Studies used a variety of different frequency protocols and stimulation methods which are outlined in the tables.

Out of the 20 studies, 17 were actually developed to support or confirm a hypothesis, and of these, all found a positive effect in at least one outcome. And in each outcome mentioned, at least one study had a positive finding. What was remarkable was that for some outcomes, only one of several protocols had a positive effect, while others were improved by a variety of different protocols. The most consistent positive findings were found in attention (4/4 studies), pain (3/3 studies) and headache/migraines (3/3). While positive effects were found in all other outcomes examined except for mood, either fewer studies had been conducted or a smaller percentage of the protocols examined were effective. Mood was examined in the 3 studies where the effects of theta were examined on a variety of outcomes. So we believe that the ability of brainwave entrainment to positively effect mood has not been properly tested in the peer reviewed literature.

Overall, we conclude that brainwave entrainment shows real potential to positively affect psychological outcomes. However, more and bigger studies need to be done, using additional outcomes and outcomes already examined. We hope that we’ve provided the necessary background to inspire future research and collaboration, so that the field of brainwave entrainment can gain recognition and momentum in the scientific literature.

To view a copy of this article, visit:

http://www.transparentcorp.com/research/

Tina L. Huang, Ph.D.
Director of Research
Transparent Corporation

Anger, stress and healing time

The last few weeks have been taken up by my favorite part of this job: testing new equipment. I’ve been working on making the BioScan and EMWave (HeartMath) devices compatible with our Mind WorkStation software. We also received the latest LightStone hardware from Wild Divine. So, I’ve been able to spend a lot of time lately in stress-free biofeedback bliss.

But some of my fellow Columbus residents haven’t been so lucky.

In a recent study by Jean-Philippe Gouina, at our own Ohio State University, 98 Columbus residents valiantly lent their forearms to the cause of science, in order to confirm that high anger levels will likely increase the time it takes to heal:

A sample of 98 community-dwelling participants received standardized blister wounds on their non-dominant forearm. After blistering, the wounds were monitored daily for 8 days to assess speed of repair.

…

Individuals exhibiting lower levels of anger control were more likely to be categorized as slow healers. The anger control variable predicted wound repair over and above differences in hostility, negative affectivity, social support, and health behaviors. Furthermore, participants with lower levels of anger control exhibited higher cortisol reactivity during the blistering procedure. This enhanced cortisol secretion was in turn related to longer time to heal.

These findings suggest that the ability to regulate the expression of one’s anger has a clinically relevant impact on wound healing.

Find the study here.

So, next time your boss yells at you, or some guy cuts you off on the highway, you will have the satisfaction of knowing that they can’t heal as fast as you.

Brainwave Entrainment And Depression

Depression is one of the main reasons I became interested in developing brainwave entrainment software. The first system I designed had a depression session I used to wean off of high doses of antidepressants. So, when new depression research surfaces, as it did late last year, I just can’t wait to get my hands on it.

First, some thoughts on depression and BWE.

Many BWE sessions for depression owe their success to the studies on Neurofeedback, which has identified some key neural characteristics of chronically depressed people. The depressed brain seems to exhibit lower overall brainwave amplitudes, and seems particularly deficient in the beta range. Alpha also seems overly abundant frontally, in the left hemisphere, and deficient in the right. You could say that the right hemisphere, which tends to be loosely associated with emotions, needs to be calmed down, while the left hemisphere, loosely associated with logic and rational thinking, needs to be stimulated into taking a more dominant role.

For people who are or have been chronically depressed, this may sound more than a little bit familiar. Rational thoughts play no part in depression. When asked why you are depressed, there really is no good excuse.

Based on the results of these EEG tests, brainwave entrainment sessions for depression were developed to stimulate beta. In some cases, alpha is sent to the right hemisphere to calm it down, while beta is sent to the left to perk it up. This is the type of session I used for myself.

In a study on Seasonal Affective Disorder (essentially, seasonal depression), Kathy Berg and David Siever used beta stimulation to raise 85% of the subjects out of depression. Anxiety and over-eating decreased. Motivation even increased. Siever has told me that more studies on depression are in the pipeline, waiting to be published.

I’ve also seen Gamma sessions used successfully for this purpose. The energizing effect alone is very beneficial to depressed individuals, who often feel as though they are “sleep walking” through life.

The latest study, which I’m going to discuss in a moment, also used beta, and reported some really extraordinary results as well.

However, depression is a broad topic. It obviously isn’t limited to people with low beta waves or frontal alpha asymmetries. Everyone gets depressed. Every few weeks I get an email from a user who used the depression session after having a bad day, or a bad week, and unfortunately most of the time a beta session just doesn’t work for them. This is not unexpected, since depression sessions are designed for the chronically depressed, not to help lighten the mood on a dreary day.

For melancholy caused by the everyday trials of human life, a pleasant relaxation session tends to work better. And there is some research to support this as well. Dr. Norman Shealy examined the effect of 30 minutes of 10 Hz stimulation, and found that it was enough to lift 60% of his subjects out of depression. He also noted an increase in serotonin levels.

High stress levels, anxiety and insomnia can also be the cause of depression. For these causes, even theta can be very helpful. But be cautious when dealing with slower frequencies, particularly theta and delta. Two separate studies (Lane, 1998, Wahbeh, 2007) found that theta and/or delta could actually increase depression scores (using the POMS, Profile of Mood States, test). Interestingly, the Lane study also showed that beta decreased those same depression scores.

Now to the new research.

Late last year,David Cantor, Ph.D. released some of the details of a new brainwave entrainment study on depression at the annual conference of the EEG and Clinical Neuroscience Society.

He used 14 Hz stimulation daily for 4 weeks, using pulsing tones and LED glasses.

Here are the results:

After 4 weeks, [Beck Depression Inventory] testing revealed “a huge drop” in self-reported depression scores in the treatment group, compared with no change in the untreated group, said Dr. Cantor.

QEEG testing also showed neurophysiologic changes in the treated patients (but not the untreated group) that corresponded to their reports of improved mood. “The QEEG changes we saw were noted in the frontal regions of the brain that have been shown by other studies to be involved in mood regulation,” he said.

The groups were then crossed over, so that the untreated group received treatment and vice versa for another 4 weeks. Similar results were noted in the newly treated group, but the group that had received the first phase of treatment showed a sustained effect of treatment, both behaviorally and neurophysiologically, even after 4 weeks of discontinuation. “That is suggestive of an enduring effect of the therapy,” Dr. Cantor said.

…

“To our knowledge, this may be one of the first studies that shows, in a crossover design, that audiovisual entrainment produces changes in brain function in particular regions that are involved in mood regulation,”

I find it particularly exciting that the effect lasted even after stimulation was discontinued. I can relate this to my own experience. I haven’t had to use the depression session hardly at all after the initial couple months of daily training.

There has been some debate over the years about whether the results of entrainment can become permanent. Some neurofeedback books I’ve read have adamantly claimed that it can’t, yet a growing body of evidence and follow-ups are starting to prove otherwise. Brainwave entrainment seems to increase the “flexibility” of the brain, or the ability to switch between one state and the next. For ADD and general cognition, research has shown the effects to be very long-lasting, and now perhaps we will start seeing similar results for other problems such as depression.

Here is an article on Cantor’s work if you’re interested: http://www.entrepreneur.com/tradejournals/article/172316583.html

A year of research and development. Dr. Huang’s work, Mind WorkStation and more.

From an outside perspective, 2007 has been a quiet year. We’ve been focused so much on research and development that we’ve neglected to release any new products.

Behind the scenes, it has been our busiest year to date.

At the beginning of 2007, we were preparing for the Windows Vista launch, making sure our products were compatible. Additionally, we attended a conference where Dr. Huang (Tina) presented her findings for the first time.

Tina has been continuing to work very hard on her study, along with psychology professor Christine Charyton, PhD. We’ve had a lot of emails asking what is taking so long. Research takes a while. If you want a paper to pass peer review, get published in a reputable journal, and have a big impact, it has to be well written and based on solid science. It is a slow, laborious and expensive process.

But this study is worth it. It is packed with useful information. The effects of brainwave entrainment (BWE) on a variety of tests have been analyzed, yielding some very interesting results and answering some important questions. Which protocols affect verbal performance over non-verbal? Which protocols are best for certain types of memory – auditory, visual, sequential, and so on? Which protocols enhance immediate recall, and which reduce it? What types of headaches can be relieved using BWE? (muscle contraction, sinusitis, migraine, etc).  What protocols have the greatest effect on attention, impulsivity, distractibility, and so on? I found one instance particularly fascinating, where there was an improvement in anger control but no effect on aggressiveness!

This is vital information that will advance the effectiveness of all BWE products in the future.

It is important to note that not only were positive results analyzed, but also negative results and studies that you will never find in marketing material or even in most books on this subject. Just as it is essential to know which protocols work for a certain condition, we feel that it is perhaps more crucial to know what protocols don’t work as intended, and could act contrary to the goal of the session.

I’m happy to report that earlier this month Tina’s paper was accepted into a prestigious peer reviewed journal with a great reputation. I will give you the details of it’s publication date as soon as I can. It is up to the journal as to when it is published, and I don’t want to step on any toes by releasing too much information too soon.

Tina and I both believe this study will be a major milestone for this field. There has never been a more comprehensive review than this, and it will draw a lot of attention to this technology. Years from now you will see this study quoted in nearly every book and subsequent study on entrainment that is released.

Along with research, we’ve also been working on development. Mind WorkStation is our latest upcoming project. I admit that I expected to have it out by now, having released the beta version in the summer. What’s the hold up? There is a lot in MWS that is completely new. There are parts of it I have been working many years perfecting. I’ve also had to work very closely with others in the field to implement many of the features, such as linking up with biofeedback and EEG hardware. One of the major goals in the creation of MWS is to inspire research. Up until this, it has simply been too difficult and expensive to experiment in this field. It usually involved building a separate device or programming something from the ground up. In MWS, there’s not a whole lot you can’t do. It is built for flexibility. For what you can’t do with the built in features, we’ve implemented a plugin interface that makes it pretty easy for programmers to interact with the application, without having to worry about signal processing or connecting to the myriad of hardware devices on the market. MWS does all that for you. With the help of our beta testers, I think we’ve nailed down a pretty slick and intuitive interface as well.

We’re just finishing it up now and expect to release it in January ’08.

Finally, throughout the year I’ve been working closely with our partners and others in the industry. They are all as busy as we are, researching, developing. Some truly fantastic hardware advances are expected early next year, and we’ve helped develop some of them.

2008 will be an incredibly exciting year for this industry.

Until then, have a happy new year everyone. Cynthia and I are ringing in the new year with sushi and Karaoke!