“Mmm! This smoothie is so good, so refreshing, so … so cold! Aah!” If it tastes so good one minute, how can it feel like someone is prying my cranium apart? This horribly agonizing experience is commonly referred to as a brain freeze, or frozen brain syndrome. Nutritionists say at least a third of the planet fall prey to the brain freeze, usually as they try to scarf down a frosty snack on a hot day. Only lasting half a minute or so (thank God) is the brain freeze’s mind bending misery, perhaps close in comparison to the malady of a migraine.

What Causes Brain Freeze?

But do we even know how the brain freeze happens? Studies have shown that it can happen as a result of the body is stimulated by intense cold, nerve-ending in the roof of the mouth freeze up, and warm blood rapidly circulates to the brain. Too much coffee colatta or Popsicle consumption in a hurry can make things much worse. Your palate meeting the tasty frozen snack is actually the culprit that put your brain freeze into action.

Is Your Brain Really Frozen?

The hard palate (which is just to say the roof of your mouth) took on the massive amount of super cold slushy when you gulped it in. There’s a cluster of nerves just behind that plate that helps protect your brain from certain temperature changes. The primary nerve in this bundle is known as the sphenopalatine nerve, and it is able to detect and adapt to heat and cold. So, that means if you eat ice cream or any other cold food, then your sphenopalatine nerve will send out shockwaves to warn other nerves in its cluster. Your nerves have basically just told the rest of your brain to get ready for a major freeze.

When you get a brain freeze, your brain doesn’t actually freeze, but your sphenopalatine nerve can’t recognize the difference between extreme cold temperatures, and eating a spoonful of ice cream. It’s actually the shrinking of the blood vessels around the brain in reaction to the cold stimuli that cause you problems. This nerve shrinkage is behind your eyes (e.g. your nasal area) is what gives you the pounding headache that brain freezes are known for. Although, the pain isn’t necessarily caused by your blood vessels shrinking, more than the flow of blood that forces them to open up again.

Why You Feel “Brain Freeze”

In all the hullabaloo of shrinking and reopening blood vessels, your nerves are also causing you some pain. Pain receptors that are positioned closely to your sphenopalatine nerve will sense that the palate has encountered something frozen, but the pain it causes will be sent into an area deeper inside your skull. That’s why you think your brain is freezing instead of the top of your mouth and jaw area.

The fastest way to stop a brain freeze, or shorten it, is to stick your warm tongue to the roof of your mouth – it’ll warm your palate back up again. And once your palate’s all warmed up, your nerve clusters will call off the hounds, and your brain freeze will come to an end. You may also want to consider taking sips of warm water while you eat your frozen treats, and don’t allow them to come in contact with the top of your mouth; this should help you minimize the “brain frozen” feeling that you may have otherwise had to deal with.

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Neurogenesis - “The birth of new neurons in the brain; also referred to as the process in which neurons are created.”The growth of new brain cells occurs in the region of the brain called the “hippocampus.” The ‘hippocampus’ is an area involved with memory, learning, and other cognitive functions. In order to live and become part of our brain, new neurons formed in the hippocampus-region need support from surrounding nutrients from blood and glial cells.

Most importantly, they need support from other surrounding neurons – otherwise these new brain cells will die. Though thousands of new brain cells are formed and produced via the hippocampus each and every day, many die quickly after birth. When we can keep them alive for this crucial period after birth, we are able to effectively boost the power of the human brain by adding new brain cells to the bank of existing cells.

Though neurogenesis is most active during prenatal development, there is growing evidence that certain activities also induce the growth of new brain cells [neurons] in the brain. Provided below are 7 researched and proven ways to grow new brain cells and provide a safe haven for effective neurogenesis.

1. An Exercise Regimen

Everybody knows that exercise is good for your overall health and heart, but in recent findings, powerful evidence has proven that exercise is great for your brain. Scientific experiments have discovered that mice consistently using running wheels had around 2x the amount of hippocampal neurons (brain cells) as the mice that didn’t exercise.

Another study at Colombia University found that humans who had a exercise training program were able to grow and maintain new brain cells and nerve cells in the hippocampus region of the brain. The specific area called the “dentate gyrus” is responsible for helping produce neurogeneis. Even more studies have discovered that those who exercised had 2 – 3x increases in the birth-rate of new neurons!

2. Eating Blueberries

Eating blueberries can trigger the growth of new brain cells? That’s right! 19-month-old rats that were put on a blueberry enriched diet [equal to about 1 cup per day for humans] were more skilled at navigating through mazes than rats who weren’t fed blueberries. Scientists know for a fact that blueberries promote the growth of new neurons. In order to track the growth of neurons, researchers injected dye into rats.

They saw that in the hippocampus region, new brain cells were generated. Scientists figure that “anthocyanin dye” – the dark bluish-dye found in blueberries caused the neurogenesis. The anthocyanin-dye contains chemicals that can cross the blood-brain barrier and produce the growth of neurons. There is growing evidence that the “anthocyanin dye” has the same effect on the brains of humans!

Related: For more information on brain foods, read the article Brain Foods: 50 Good Brain Foods.

3. Taking Time for Meditation

Meditation has always thought to have been beneficial for the brain. Recent compelling evidence from scientific researchers at Yale, Harvard, and Massachusetts Institute of Technology revealed that meditation can allow us to “grow bigger brains.” Though this isn’t the same thing as neurogenesis, meditation could very well be an activity that boosts the birth rate of neurons.

Researchers also discovered that meditators literally had an altered-physical brain structure compared to non-meditators. Brain scanning technology [i.e. MRIs] showed that meditation boosted thickness of brain structure dealing with attention, sensory input, and memory functions. The thickening was found to be more noticeable in adults than younger individuals. It’s interesting because the same sections of our cortex that meditation thickens, tend to get thinner as we age.

Meditation is known to boost brain activity, coherency of brain waves, strengthen neural connections, and thicken gray matter. Though scientists haven’t confirmed the effects of meditation and its ability to aid neurogenesis [due to complexity issues], there is a likely possibility that it helps.

4. Antidepressant Drugs

Scientific research by the National Institute of Mental Health has proven that antidepressants work by allowing our brains to grow new brain cells (neurons). In a 2003 study, scientists discovered that when they blocked the formation of new neurons in the hippocampus brain region, behavioral effects of the antidepressant Prozac [Fluoxetine] were diminished.

Research has already understood that depression, stress, and anxiety disorders can cause death of neurons in the brain. More studies have demonstrated that most other antidepressants on the market can and will trigger the growth of new neurons. Even more interesting is the fact that besides humans, adult animals grow new neurons when given antidepressant drugs.

Though there are many other interactions in the brain with antidepressants, their primary beneficial effect from them is derived from their ability to produce neurogenesis. Now if scientists can only figure out a way to induce the amount of neurogenesis that antidepressant medication does without creating a new drug!

5. An Enriched Environment

Science has long known that living in a mentally stimulating environment vs. an impoverished environment is far better for brain development. Research has found that exposure to an enriched environment enhances neurogenesis functioning and is able to regulate emotionality.

Scientists have found that memory-based tasks were far improved in the hippocampus region of the brain when human beings are raised in a healthy, enriched environment. One study found that mice put in stimulating environments actually had larger hippocampus regions than did those living in “standard” or “poor” laboratory conditions. They discovered a direct correlation between an enriched environment and the amount of neurons produced in the brains of mice. This had a significant effect on neurogenesis!

6. The Act of “Learning”

Though scientists have long known that new brain cells are able “enhance learning” – they never thought that “learning” could actually cause the birth of new brain cells… that is, until recently. In recent animal studies, researchers have found that there was a direct relationship between “learning” and the survival rate of newly-birthed brain cells.

When researchers taught certain rodents a wide-variety of cognitive tasks which involved a wide-range of brain areas – scientists found that the more the animal “learned” – the more new neurons were able to survive in the hippocampus. Scientists have made it clear that “learning” can increase the presence of new neurons in the brain.

Brain cells that are born in the hippocampus, which normally die off, are literally “rescued” by “learning” experiences. There is still plenty of research being conducted in this area and not all sources agree. However, your best bet is to keep your brain power boosted and your mind sharp. Always try to learn something new!

7. Restricting Caloric Intake

The phenomena of calorie restriction has continued to puzzle researchers. They have found that eating less food can lead to significant increases in longevity. Even when starting calorie restriction in middle age, it is able to produce around a ten to twenty percent increase in life-span. It has also been associated with hundreds of biological changes and can harbor our ability to produce new brain cells.

Restricting calorie intake has been associated with increases in neurogenesis and a better overall neuroprotective effect in the brain. Scientists have found that calorie-restricted animals nearly always stay active and healthy up until the end of their lives’. This phenomena has also been associated with a significantly lowered likelihood of developing a degenerative brain disease and can even produce new nerve cells!

*8. Infared Light Helmets

Though the use of infared light helmets is relatively new, researchers believe that they may help patients with Alzheimer’s disease by helping them grow new brain cells. Developer of this infared light helmet, Dr. Gordon Dougal, (also the director of medical research at medical research company Virulite) believes the helmet will hit the market about 1 year from now. It works by aiming low levels of infared light at the wearer’s brain. Next, it stimulates neurogenesis in the brain, suggests research.

More on how this works according to its inventor [Dr. Gordon Dougal]: “How we hope it’s going to work is that the infrared light will be facing inside the helmet onto the actual person, onto their skin, onto their brain, and actually goes on the frontal part of the bones, so it goes onto the actual front part of the brain and the side of the brain.”

“The side of the head and their skull are relatively thin, so the light will penetrate the skull and treat the underlying brain tissue. And the top of the head is also quite thin, and the light will penetrate the brain tissue at that point.”

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For more information, view the sources:

LE Magazine: June 2002 – Calorie Restriction, Exercise, Hormone Replacement, and Phytonutrients Fight Aging – Age Conference – Madison, Wisconsin

Harvard University – Meditation found to increase brain size – Mental calisthenics bulk up some layers By William J. Cromie – Harvard News Office http://www.news.harvard.edu/gazette/daily/2006/01/23-meditation.html

Antidepressants Grow New Brain Cells – About.com; http://mentalhealth.about.com/cs/psychopharmacology/a/neurogenesis.htm

Sci STKE. 2003 Aug; (195):318. Antidepressants and Hippocampal Neurogenesis. Santarelli L, Saxe M, Gross A, Surget A, Battaglia F, Dulawa S, Weisstaub N, Lee J, Duman R, Arancio O, Belzung, Hen R.

The Journal of Neuroscience. 2007 Mar; 27(13): 3252-3259. Experience-Specific Functional Modification of the Dentate Gyrus through Adult Neurogenesis: A Critical Period during an Immature Stage. Tashiro A, Makino H, Gage FH.

Stanford University Research In Progress: HD & Lifestyle http://www.stanford.edu/group/hopes/rltdsci/inprogress/ae2.html

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Introduction

Ever wonder how you’re brain is able to control the perception of time? At times it seems as if life is flying by – especially when we are involved in a fun activity or event. At other times, though, when we are stressed out or witness a scary event, time seems to stop or even freeze in our brains. Our perception of time is different from person to person, and definitely has a deep biological-rooted influence from within our brains.

Though we have things like watches and clocks to help us keep track of time, our brain is involved in the perception of how fast time passes. Like I’ve already mentioned, some people feel that one hour of listening to country music may go by extremely quick, while for others [that maybe aren't interested in this genre] feel as if one hour was actually 3 or 4 hours. Being able to keep track of time is a skill that our brains’ have that allows us to determine what is happening in our surroundings and when to respond to that event.

Simple functions that we take for granted such as: hearing speech are even involved in our brain’s perception of time. As an example: we need to tell where a voice is coming from, how long the sound of it takes to reach our ears, etc. Also, when we respond to voices through the act of “talking,” we need to be timely with our responses.

Animals and studies of “time perception”

Researchers have found that telling time is even widely utilized by animals. University of Edinburgh researchers were able to study hummingbirds to determine how they told time. Researchers used fake flowers with sugar inside. They found that after hummingbirds drank the sweet nectar contained within real flowers, it took time for the flowers to replenish their nectar supply. The fake flowers were refilled every 10 minutes , while the real flowers were filled every 20 minutes. The hummingbirds were able to catch on to the time period it took for the nectar came back into both the real and the fake flowers.

Many other animals are also great time-tellers. Research on rats at the University of Georgia showed that rats do a phenomenal job at telling time. Rats can be taught to wait over 2 days after a meal to poke their noses through a trough and be given fresh food. Psychologists have hypothesized [for over 40 years] that both animals and human beings kept track of time with a biological version of a “stopwatch.” They strongly believed that within our brains, we had a “series of pulses” that were being generated. They thought that when our brains needed to “time an event,” a gate opened and those electrical pulsations turned into a “counting device.

The flawed brain-clock model of “time perception”

There was definitely good reasoning behind the brain-clock model of time perception. You’re time perception always will speed up when you are caught up in a pleasurable or fun event, while your brain will naturally slow down time perception when you are in a place you dislike or feel stressed out. These good and bad experiences were believed by psychologists to trigger the “pulsation generator” within our brains – thus speeding or slowing time depending on the given situation.

With that said, the biological roots within the brain don’t work like “clocks” that we understand. Neurons in our brain are able to produce steady pulses, however, our brain doesn’t have what it takes to count accurate pulses for even a few seconds. How we tell time is definitely far from the way a clock tells time. This is why scientists had to dismiss the brain-clock theory mentioned above.

Had our brains been built to work like that, we’d definitely be able to do a great job at estimating long periods of time better than short ones. Any individual or single pulses from the hypothetical clock within would be either a bit too slow, or a bit too fast. In short periods of time, the brain would begin to retain just a few short pulses, leaving plenty of room for error. The extra pulses that our brain would naturally error, would cancel themselves out [i.e. errors of telling time would be canceled out by the brain]. Though it sounds like it could be true, it’s not. Whenever we estimate longer periods of time, our errors don’t cancel themselves out – they keep accumulating.

What does our brain use to tell time?

At this day in age, tons of new breakthroughs and experiments are surfacing to help scientists better understand time within the brain. Things such as: studying genetically engineered mice, computer simulations in combination with E.E.G.’s, are being used to help scientists. The results of their studies prove that our brain doesn’t use any form of a “stopwatch.”

Our brains do not work like clocks or stopwatches that come to mind when we think of elapsed time. Instead, our brains utilize several other methods in order to tell time. Neuroscientist Dean Buonomano from U.C.L.A. believes that our brains tell time like they were observing “ripples in a pond.” He continues to argue that they perceive time in “fractions of seconds.” Let’s say you are listening to the sound of a summer cricket. The criket’s chirps are split by just one-tenth of a second. The cricket’s very first chirp immediately perks up our auditory neurons.

Sound signals are sensed by the neurons for less than half a second – same time as it takes ripples from a skimming a rock across the river to disappear. When the second cricket chirp is heard, the auditory neurons are still perked up. Therefore, the second chirp creates a different signal pattern. Dean Buonomano believes that our brains are able to compare the first pattern to the second patter in order to determine how much time has elapsed. Basically, the brain doesn’t contain an internal clock, because the telling of time is fixed in our neuronal behavior.

Dean Buonomano Theory vs. Warren Meck Theory

Should the U.C.L.A. researcher’s [Dean Buonomano] theory turn out to be correct, he will have explained only the “fast time telling” within the brain. Why? Because after half-of-a-second, the ripples in our brain clear out. On a bigger scale, which would range from a few seconds to a few hours, there must be a different way to study the brain’s time control processing.

That’s where Duke University’s Warren Meck comes into play. He has a different theory stating that: the brain measures long periods of time by producing pulses. However, he also believes that the brain doesn’t count the pulses like the way a “clock does.” He strongly believes that the brain listens to the pulses in the same way that our ears listen to music.

Warren Meck started developing his first “musical model” of time processing when he was studying the time perception of rodents; more specifically, the time perception of rats. All that Meck needed to do in order to kill their time processing was to destroy certain neuronal clusters within their brains. After taking a closer look at the situation, Meck found that some of these neurons differed from the rest of the neurons in the brain.

Each neuron was linked to a at least 20,000 other neurons in the brain. The “linked neurons” were able to be seen throughout the cortex. Many even linked to the outer parts of the brain which handle “sophisticated information processing.” While other neurons were linked to “controlling vision,” and even others worked to bind other areas into our perception. Because these neurons received many signals from “all over the brain,” he believes that these medium spiny neurons provide us with an accurate perception of time.

Picture yourself listening to a 30 second constant sound. At the beginning of listening to the constant sound, your neurons [found within your cortex] will reset themselves in order to fire in synchronized fashion. Some of the neurons fire faster than others, while others remain inactive. In between one split second and the next, the medium spiny neurons are able to read a unique pattern of signals from the many [20,000 +] interconnected neurons.

The pattern changes similar to pitch changes in between various notes of music. When the 30 seconds of the beat are up, the medium spiny neurons are able to “listen” to the “pitch changes” to determine the amount of elapsed time. Warren Meck has been able to provide evidence supporting his theory. How? Warren has recorded neuronal electrical activity and analyzed them deeply and has studied individuals with a “skewed sense of time.”

Healthy brains vs. Drugged brains & time perception

There are also specific neurotransmitters like dopamine which control the pulsing of neurons. Crystal meth and cocaine are examples of drugs that control the pulsing rate of neuron groups. They do this by overpowering the brain with abnormally high levels of dopamine. Several studies have proven the increased dopamine to have a profound effect on changing the perception of time.

In 2007, U.C.L.A. also ran an experiment. In the experiment, scientists rang a bell after 53 seconds of pure silence. Healthy individuals were told to guess how much time had passed. Most guessed an average of 67 seconds of time had elapsed. People on stimulants [which boost the amount of dopamine in the brain] guessed that an average of 91 seconds had passed. Many other drugs have the exact opposite effect on the amount of dopamine in the brain – thus compressing the subjective experience of time.

In even the most healthy brains, the processing of time varies. Staring at a scary face for 5 seconds feels significantly longer than staring at a neutral or happy one. It may not even be coincidence that pulse-generating neurons are embedded within regions of the brain that process emotionally-charged sounds and sights. Recently, researcher Amelia Hunt from Harvard University addressed the idea that every time we move our eyes, we may in fact be “pushing back our mental time.”

Amelia Hunt’s research at Harvard University

Even more recently, Amelia Hunt conducted an experiment where she had individuals stare “straight ahead” with a ticking clock off to one side of their gazes. Hunt then asked the individuals to move their eyes in order to see the clock. She told them to attempt to remember the time each time they had looked at the clock. On average, participants reported seeing the clock about four one-hundreths of a second before their eyes actually arrived at the clock.

The act of “pushing back” time may actually be a good thing, believes Hunt. It may allow us to cope with our slightly imperfect nervous systems. Every person has a highly-dense patch of light-sensitive cells in our retinas. These cells have been dubbed the name: fovea. We must move and jerk our eyes around several times in order for our fovea to generate an accurate, detailed image of our environment and surroundings; this gives the fovea enough time for scaling the features of our surroundings. The stream of signals from our eyes creates a series of jumps or bumps on the road. The human brain naturally will then allude us to believe that we are experiencing one complete “flow of reality.” When our brain realizes that it is still editing the “signaling jumps,” we may have errors in time perception.

Embedding time in our memories

However, the most shocking reworking of time may be the way it gets embedded in our memories. We usually always recall memories that include both: what happened, and when it happened. We understand how much time has passed since a certain past event by drumming up an event of the old memory. People who have brain damage as a result from injury or surgery – which depleted a certain part of the brain – gives researchers clues as to the way the brain embeds time within memories.

In 2007, scientists from France studied a group of individuals that were suffering from left-temporal lobe brain damage. The study participants then watched a film in which a familiar object appeared on the screen and reappeared a few minutes later [8 minutes later]. The study participants were then told to guess how much time had passed since first seeing the familiar object and seeing it for a second time. On average, the brain-damaged participants thought 8 minutes was really around 13 minutes. Healthy brain subjects were only off in guessing by roughly only one minute.

These type of experiments are great progress for researchers and scientists. They are slowly bridging the gap and honing in more on the regions of the brain which store memories of time. What is still unknown, is how these brain regions are able to record and understand time. Listening in on the brain’s signaling for a few minutes is one thing, but it is completely different [and much more complex] to understand how the brain’s neural networks of memories are able to deposit and withdraw [for later recollection] elapsed time during certain events.

Compressing memories of time [Berlin research]

It is interesting though, because scientists have by no means given up on understanding time-control in the brain. Researchers in Berlin, Germany have been working to build an accurate model of how memories may embed time. When neurons produce a normal generation of signals, some signals are received sooner – while others, a little later. These Berlin researchers believe that as the neurons communicate with one another, they pass the signals. While they are passing the signals, they can create slight adjustments ["wobbles"] – some bigger, some smaller. With these tiny “wobbles,” the brain is able to embed memories of time by compressing them. The brain is able to compress memories of several seconds down to “several hundreths” of a second. This allows the brain to save it’s space and easily have enough room to store many memories.

When your brain stores time in its memories, the brain is able to alter it in another significant way. Your brain could record the time such that we recall the events in a “backwards order.” M.I.T. researchers found that the brain was able to form reverse memories. They ran an experiment which included rats running down a track and stopping to eat food at the end of the track. When rats become more familiar with their environment, individual neurons became more active when they reached familiar spots.

Researchers discovered what are called “place cells.” These “place cells” fired off signals when rats moved to different places along the track. When the rats took a break and stopped to eat, researchers checked their brain activity again. They realized that the “place cells” fired again – due to the fact that memories of the track became stronger within their brains. However, the “place neurons” at the end of the track signaled first. The ones at the beginning of the track fired last. It is definitely possible, though, that we can reverse time processing in our memories in order to focus on our brains’ on something rewarding or a goal. Though we are not free from time, we are able to maintain some control over it. Our brains can bend it and twist it to properly fit our needs and reality.

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Gay brains similar to straight brains of the opposite sex

Recently, brain scans have provided scientists with some of the best evidence that ‘being gay’ or ‘being straight’ is part of a biologically-fixed genetic trait. The brain scans revealed – that in homosexuals – key brain structures responsible for anxiety, mood, emotion, and aggressiveness are extremely similar to those in straight people of the opposite sex.

To put the findings in simpler terms:

• homosexual (gay) male brains = heterosexual (straight) female brains

• homosexual (gay) female brains = heterosexual (straight) male brains

Ivanka Savic, the leader of the study, said that, “Scientists figure that the differences between straight and gay brains of the same sex are likely already set early in the womb or during early infancy.” Ivanka held and carried out this groundbreaking study at the Karolinska Institute in Stockholm, Sweden. Ivanka continues by stating, “This is the most robust measure so far of cerebral differences between homosexual and heterosexual subjects.”

Most previous studies have also discovered differences in brain structure and activity between gay and straight individuals. However, most of these studies relied on individuals’ responses to sexuality driven cues that may have been learned (i.e. rating the attractiveness of male / female faces).

How the study worked

To avoid relying on individuals’ responses to sexuality driven cues, researchers chose to measure brain parameters that were most likely ‘fixed’ at birth. Savic said that the whole point of this study was to show brain parameters that differ; parameters that couldn’t be changed via cognitive processes or learning.

First, the researchers utilized fMRI brain scans to determine the shape / structure of the brains and their overall volume. A group of 90 volunteers that consisted of 25 straight (heterosexual) individuals [of each gender] and 20 gay (homosexual) individuals [of each gender] were scanned.

The results of the “gay brain” study

The results of this “gay brain” vs. “straight brain” study show that straight men tended to have more asymmetric brains, with the right-hemisphere slightly larger than the left. On the other hand, gay men had symmetrical brains just like the brains of straight women.

The research team then used PET scans to determine and measure the amount of blood flow to the amygdala – a part of the brain that regulates aggression and fear. The PET scan images showed how the amygdala – which is connected to other parts of the brain – gave clues as to how it might influence behavior. Researchers learned that patterns of connectivity in the brains of gay men matched those of straight women. In straight women, the connections were mainly into regions of the brain that manifest the emotion “fear” as “intense anxiety.”

The brain connection to mood disorders

Savic, leader of this study added, “The regions involved in phobia, anxiety and depression overlap with the pattern we see from the amygdala.” This is very significant because it correlates with data showing that women are at least 3 times more likely than men to suffer from mood disorders and depression. Gay men tend to have much higher rates of depression too. It’s difficult to know whether the link to mood disorders is due to homophobia, biological traits, or a result of the stigma associated with being gay.

In lesbians and straight men, the amygdala feeds its signals mainly into the straitum and the sensorimotor cortex – 2 regions of the brain associated with generating a “flight or fight” response. Researchers say that it’s more of an “action-determined” response than it is in women.

What the experts had to say

One of the leading researchers in the field of “sexual orientation” at Queen Mary College, London, UK – Qazi Rahman – said, “This study demonstrates that homosexuals of both sexes show strong cross-sex shifts in brain symmetry.” Qazi later added, “The connectivity differences reported in the amygdala are striking.”

Simon LeVay, a prominent United States author who reported in 1991 about finding differences in the hypothalamus (part of the brain) between gay and straight men. After viewing this study, Simon said, “Paradoxically, it’s more informative to look at things that have no direct connection with sexual orientation, and that’s where this study scores.”

Ivanka Savic, the study leader, understands the fact that her study cannot determine whether the homosexual brain differences are inherited or a result from overexposure to certain sex-hormones in the womb (i.e. estrogen and testosterone).

Journal reference: The National Academy of Sciences Proceedings

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New synaptic molecular evolution theory

Human intelligence has little or nothing to do with brain size – scientists have known this for awhile. Having a bigger brain will not necessarily make you more intelligent than another person. A relatively recent report by the Daily Mail Newspaper discussed a study that compared human brains to the brains of other species. The research and its findings were very interesting.

Researchers found that mammals have a higher percentage of proteins in the synapses – brain regions of interconnected nerves. They also discovered that of the 600 proteins found within the synapses of mammalian brains, about half of those synapses are found in invertebrates. Only one-quarter were found in single-celled organisms – which are a species without nerves.

The Daily Mail Newspaper quoted one lead researcher who stated, “This work leads to a new and simple model for understanding the origins and diversity of brains and behavior in all species. We are one step closer to understanding the logic behind the complexity of human brains.”

This highly-complex brain study contributes knowledge about the differences in a highly-important group of brain proteins between species. This study did not produce a comparison between the relative contributions of differences in these proteins. Nor did the study fully determine the relation of brain size to intelligence in humans or any other species. Because of the inconclusiveness, it is virtually impossible to draw any conclusions about their importance. Our brains are highly-complex organs and many external and internal factors determine differences in behavior and learning in all types of species.

What were the results of this study?

Researchers discovered genes which encoded proteins similar to the mouse postsynaptic proteins in all of the species – even yeast! There were obvious differences in the numbers of types of the proteins between the yeast, vertebrates and invertebrates. Basically, as organisms became more complex, they were found to contain a wider variety of postsynaptic proteins. In yeast, a species without nerves, these proteins were utilized in a wide-variety of jobs including: decision making, breaking down proteins, moving substances around the cell, and responding to the environment.

When comparing the mice proteins with the fruit fly proteins, the mice showed a much more complex range of postsynaptic proteins. Also, different regions of the mice’s brain displayed different combinations and levels of proteins. This eludes to the fact that they may actually be responsible for some of the different functions in these areas of the brain… Pretty confusing stuff, but it makes sense.

What were researchers able to learn from these results?

Researchers in this study believe that basic proteins that make up synapses have evolved over time to become more complex. This evolution of proteins has created differences in cognitive abilities between different species and to the adaptation of different regions of the brain for different functions.

Basically, this study has contributed to knowledge about the differences in certain groups of brain-proteins between different groups of species. The brain is an extremely complex organ and there are many differences between different species which create differences in cognitive abilities and behavior. Humans have a significantly more complex set of synapse proteins than other species. This allows us to have cognitive differences in behavior, thinking, memory, etc.

Why was this study done?

They hoped to determine how the synapses have evolved and why different types of species behave in more complex ways. Researchers also make it a point to note that all existing discussions of how the brain and behavior evolved failed to take into account the possibility of “synaptic molecular evolution.” Researchers worked by looking at differences between synapses in different species. Species ranged from: single-celled species to humans.

To take into account “synaptic molecular evolution,” scientists looked at proteins that were located in a certain part of the synapse – called the postsynaptic region. For starters, scientists took sequences of certain genes which contained the blueprints for 651 proteins found in the postsynaptic regions of mice. They then used computers to match similar sequences in the genetic coding of 19 different species.

The species included: simple species that did not have nervous systems like yeast (a single-celled organism), and a range of organisms with nervous systems such as: invertebrates (i.e. insects or worms), non-mammalian vertebrates (i.e. fish), and mammalian vertebrates (rats, chimpanzees, and human beings).

The researchers looked into the function of these proteins in yeast. Next, they determined which proteins were found in the postsynaptic regions of fruit flies. They then compared the fruit flies postsynaptic regions with that of mice. Eventually, they were able to look into mice’s brains and discover where these different proteins were found.

In my opinion, this study can get a little bit confusing. There is still a lot of material that was left unexplained that is still being researched. Based on this study, scientists will have a solid foundation developed for researching new molecular evolution theories. This is one of the latest “evolution of brain power” theories that has surfaced, so I figured that I’d share it with the blog. I will keep you all updated if I discover a new one!

Where did the story come from?

Dr. Richard Emes and colleagues from Keele University, Edinburgh University, the Wellcome Trust Sanger Institute, and the Okinawa Institute of Science and Technology did the research. Their research study was funded by Wellcome Trust, the Medical Research Council, Edinburgh University, GlaxoSmithKline, the e-Science Institute, and the European Molecular Biology Organisation. The study was published in the Nature Neuroscience medical journal.

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Researchers discover why schizophrenia symptoms vary depending on the individual

A relatively new study offers hope towards learning how certain individuals behave during an episode of psychosis. The study, which appeared in the June 18th issue of The Journal of Neuroscience, discussed the brain activity of healthy individuals compared with participants who ingested the drug “ketamine.” The club drug, and old anesthesia drug, ketamine, is known to induce symptoms of psychosis that mimic psychosis episodes and schizophrenia. The findings in this “ketamine study” help us explain why the symptoms of schizophrenia are completely unique depending on the individual. The results will also help make treatments of psychosis and schizophrenia more personal and uniquely formatted to fit the specific individual needs.

In psychosis, researchers often wonder why one individual may suffer from only odd perceptions, while others are haunted by paranoid-type beliefs that they are being hunted down by the C.I.A., and in other cases, there appears to be only severe disorganization of thoughts. Because of the wide-variety of symptoms, Paul Fletcher, a licensed M.D. at Cambridge University decided to study it.

Paul Fletcher and researchers hypothesized that different symptoms have specific biological links: each of which may disrupt normal cognition and brain function. The researchers were drawn to the fact that individual differences in normal brain activity could determine which cognitive processes are most at risk of being affected by psychosis, schizophrenia, or a drug-induced state.

Schizophrenia is a disease with symptoms that include what are referred to as negative symptoms and positive symptoms. Negative symptoms include: the loss of normal behaviors, reductions in speech, and social withdrawal. Positive symptoms include: hallucinations (auditory, visual), delusions, and disordered thought. Because everyone is unique, each person suffering from the devastating disease of schizophrenia or psychosis could have significantly different symptoms than another person with the disease.

Ketamine, also called “Special K,” is an often-abused analgesic that is able to induce both positive and negative symptoms in individuals. Like psychosis, the side-effects of ketamine vary from individual to individual and are unpredictable. Ketamine is a drug that works by blocking certain receptors in the brain that regulate the neurotransmitter glutamate – also implicated in schizophrenia.

How the study worked

Using MRI imaging, researchers made profiles of individuals either exposed to ketamine or a placebo while the participants did a wide-variety of cognitive tests. The researchers proceeded to evaluate the behaviors of the participants by using medically accepted psychiatric scales. Exactly one month after the evaluation, participants returned to repeat the testing in the opposite condition. Basically, each participant had an M.R.I. taken and was observed after exposure to both ketamine and the placebo. (To clear up any misunderstanding: Each person that had ketamine the first time had the placebo the second time… Each person that had the placebo the first time had ketamine the second time. M.R.I.’s were taken of every participant – both rounds of the study)…

The results of the study: brain activity linked to symptoms

The team of researchers discovered that increased brain activity during some tests with the placebo condition predicted the behaviors when in the psychosis-like ketamine condition. What the researchers found was very interesting! Participants who displayed more frontal and temporal brain activity while “imagining the sounds of voices” in the placebo condition, were very likely to experience strange perceptions during the ketamine condition.

The others, who showed increased activity in the frontal and temporal sections of the brain while trying to complete simple sentences, were much more likely to have disordered thinking while exposed to the ketamine. The brain’s frontal lobe is involved in executive functions such as: planning, making decisions, advanced thinking, and analyzing our environment, while the brain’s temporal lobe is primarily involved in memory, hearing, and speech.

In contrast experiencing positive symptoms, participants who displayed an increased frontal lobe response to a test involving attention while taking a placebo, were increasingly vulnerable to experiencing negative symptoms while observed under the drug ketamine. Also, participants that displayed increased response in a combination of the frontal lobe, thalamus region, and caudate region – (linked brain circuitry that allow us to carry out motor and executive functions — an area often impaired in psychosis and schizophrenia–) – had a tendency to display negative symptoms while under the effects of ketamine.

Groundbreaking research? Maybe not, but it’s a step in the right direction!

This research is a huge step towards heightening our understanding of the mysterious diseases of schizophrenia and psychosis (2 fairly interchangeable terms, with slightly different diagnoses). Now, at least researchers have some form of biological link towards determining and demystifying the unique set of symptoms that are experienced. The researchers also noted the fact that the participants that were under exposure to ketamine were not at risk towards developing any sort of mental disorder. The participants also provided us with further understanding of how certain drugs and certain diseases can induce different states of consciousness in different people.

This study provides us with insight that may allow us to successfully predict psychotic symptoms induced by drugs and disease. A study author, Fletcher said, “This perhaps raises the prospect of early intervention strategies targeted toward schizophrenia patients’ individual patterns of symptom vulnerability.” I completely agree here, this study appears to be slightly groundbreaking, although I feel that researchers are only at the tip of the iceberg. There is a lot of work that still needs to be done in the area of the largely misunderstood psychosis / schizophrenia, but scientists are giving those that suffer a boosted morale and a sense of hope.

Note: The research was supported by the Medical Research Council, The Wellcome Trust, and the Bernard Wolfe Health Neuroscience Fund.

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Hearing voices: not as uncommon as you may think

Contrary to popular belief, not only schizophrenics experience auditory hallucinations a.K.a. hear voices. Many people who are not even mentally ill often report hearing claps, whistles, buzzing voices, or even music in their head. Around 70 % of schizophrenics hear voices that interrupt their thought patterns on a consistent basis and 15% of people with mood disorders experience auditory hallucinations. However, hearing noises or voices isn’t necessarily a sign of mental illness.

According to Scientific American Mind magazine, hearing auditory hallucinations may not be as uncommon as the public thinks. In 1983 a study showed that 70% of a 375 college-student survey admitted to hearing voices at leas once in their lives. Many students thought that they heard dead relatives, divine beings, and even their own thoughts in vocal form. Auditory hallucinations during waking or directly before sleep were recorded by 40% of the study participants.

A 1991 National Institute of Mental Health study reported 5% of 15,000 Americans who had experienced auditory hallucinations, heard them for a complete year. Only 1/3 of the 5% that had experienced the hallucinations met the criteria for a psychiatric diagnosis. Thomas Bock, a psychotherapist and director of the outpatient psychosis service at the University Medical Center of Hamburg-Eppendorf, Germany, at least 3% to 5% of the entire population in western Europe and the United States hear voices. In comparison to those findings, the disease schizophrenia only affects every 1 in 100 people.

How do these hallucinations happen?

Psychotherapist Thomas Bock explains that they arise from “too much internal stimulation” or “too little external stimulation.” Bock thinks that auditory hallucinations maybe a cause of people holding too much thought and emotion on the inside. Many people that hear voices have suffered a degree of trauma as a child or adult such as: rape, abuse, isolation, or a severe accident.

The unresolved conflicts resulting from traumas trigger signals which Bock thinks signifies that they need to listen more to their inner voice. Though there are many speculations as to what causes one to hear voices, some researchers agree that the hallucinations are due to a failure in a feedback circuit within the brain.

This feedback circuit normally tells you when “you” are talking or thinking — not someone else. The hypothesis that “self-talk” or “internal dialogue” gets misaligned with normal internal feedback applies to schizophrenics as well.

How can you tell if a person is hearing voices or has schizophrenia?

Well, researchers also studied and compared those who had no psychiatric symptoms to those already diagnosed with schizophrenia. Participants in the study listened to distorted voices of themselves — they were told to press a button if they thought they were listening to themselves or another person.

People already diagnosed with schizophrenia had much greater difficulty identifying their own voices. Also, non-schizophrenics did not report negative commentary in their hallucinations — schizophrenics heard negative and degrading voices. Both groups of people reported commentary on the vocalization of their thoughts, yet non-mentally ill participants heard encouraging statements like: “You can do it” or “it really wasn’t your fault.” Non-mentally ill patients also felt more in control of their voices, while schizophrenics reported little or no control.

What brain-imaging has shown

Brain-imaging studies have also shown the physiological aspects that happen in verbal hallucinations. During schizophrenic hallucinations, a huge increase of brain activity was shown in Broca’s area, an area involved in producing speech, not hearing it. They also found large amounts of activity in the brain’s primary auditory cortex — an area that normally processes sounds from the outside environment. Schizophrenics brain’s responded to their auditory hallucinations the same way as a regular brain responds to chatting with others.

Several causes of auditory hallucinations:

• Mental illness — People with various forms of mental illness can hear voices. It is most common to hear voices in schizophrenia, but in bipolar disorder and severe forms of depression, some people hear voices.

• Social isolation — A common trait of people who experience auditory hallucinations is social isolation. Social isolation causes the brain to receive too little simulation from the outside world. Withdrawn social activity can fuel hallucinations for non-schizophrenics, which in-turn will fuel social rejection.

• Poor stimulation for extended periods — Several hikers and sailors that have survived poor stimulation for long periods of time have reported auditory hallucinations.

• Sensory deprivation victims — Some victims of sensory deprivation victims often report hearing voices. Sleep deprivation when taken to extremes, can commonly cause auditory hallucinations.

• People with hearing loss — Musical hallucinations in people who have forms of hearing loss are actually quite common. Scientists think that the brain records auditory information that it has stored over one’s lifetime. When the external output (hearing) is eliminated, the deposited signals can live on in the form of hearing music — when it’s not playing…

• Spiritual phenomena — Many very spiritual or religious people claim to have heard voices in meditations, rituals, or during enlightening experiences. Very spiritual people claim to have been talking with others in another dimension, talking to “spirit guides,” deceased relatives, or another “higher being.”

How researchers are trying to quiet the voices

Currently, for those who do suffer from hearing voices, anti-psychotic medications work best for eliminating symptoms. Trans-magnetic-stimulation (TMS) has also been used by scientists as a method of decreasing the amount of brain activity in specific regions by using magnetic fields. The targeted areas of TMS have been those involved in speech-processing.

In 2005, researchers were able to suppress acoustic hallucinations in 50 patients for a total time period of 3 + months! Studies have also shown that the sooner one talks to someone about hearing the voices, the sooner the voices disappear. They have also shown that how a person views their voices is almost always a direct reflection of what the person actually hears.

Researchers and therapists are also helping victims learn how to “reframe the voices” and become more conscious of their illness. Therapists help to make sufferers masters of their own mind — by providing victims with valuable coping techniques. One interesting coping technique that has been used on several patients is that of allowing voices to “come out for conversation” during a set period of time.

By allowing them to come out for a set period, they tend not to usually bother the victims for the rest of the day. Another interesting phenomenon that scientists have found is that the vocal hallucinations that a victim experiences are usually a mirror reflection of their social life with real people.

It’s not always necessary to eliminate hearing voices from your life. Researchers think that whether or not a person should attempt to eliminate voices should result from whether the voices are positive or negative. When voices get negative, swear at the victim, talk trash, or degrade the person hearing them, it is definitely recommended to get help.

On the other hand, if a person hears positive voices, is socially active, and is not isolated, chances are good that the person can comfortably lead a fulfilling life. However, friends and family should still not rule out mental illness if one does hear “positive voices.” Some people manage to convince themselves that “negative voices” actually are well-meaning.

What should you learn from this article?

You should realize that hearing voices is actually fairly common nowadays. If you are hearing voices, don’t be afraid to share them with others — it may quiet them a little bit. The type, or mood of the voice, can usually distinguish a schizophrenic from a non-schizophrenic. For a nice video clip on what it feels like to experience schizophrenia: check this out — it’s a “virtual simulation.”

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Article sources: Scientific American Mind December 2006 / January 2007 Issue, Article: Hearing Voices by Bettina Thraenhardt — a psychologist and science journalist.

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