Category Archives: Neuroscience

Rescuing the amygdala from the swamp of pop culture

Judge Brown - Boston Legal

Rescuing the amygdala from the swamp of pop culture

Watching shows flirt loosely with scientific research to create pop cultured myths is like nails on a blackboard. It is the kind of talk that goes down well when trying to impress in a bar. So many tv-shows these days are often based on apocryphal pseudo-science myths – to the point were the myth becomes a fact amongst the television fans of crime drama. CSI, CSI New York, CSI Miami, House, Criminal Minds (one of the better shows), NCIS, NCIS Los Angeles. This really has nothing to do with the quality of the shows for what they are; pure entertainment – but writers get paid to do their job – and they should fact check.

The Amygdala And Fear Are Not The Same Thing

In a 2007 episode of the television show Boston Legal, a character claimed to have figured out that a cop was racist because his amygdala activated – displaying fear, when they showed him pictures of black people. This link between the amygdala and fear – especially a fear of others unlike us, has gone too far, not only in pop culture, but also in psychological science, say the authors of a new paper which will be published in the February issue of Current Directions in Psychological Science, a journal of the Association for Psychological Science.

Indeed, many experiments have found that the amygdala is active when people are afraid. But it also activates at other times, for example in response to pleasant photographs and happy faces.

The misconception came from how scientists first approached studying the brain. A lot of people came to the amygdala from the study of fear, says Wil Cunningham of Ohio State University, who co wrote the new paper with Tobias Brosch of New York University. “It’s a great emotion to study because it’s very important, evolutionarily, and we know a lot about fear in animals,” Cunningham says. Almost every study of fear finds that the amygdala is active. But that doesn’t mean every spark of activity in the amygdala means the person is afraid.

Instead, the amygdala seems to be doing something more subtle: processing events that are related to what a person cares about at the moment. So if you’re in a scary situation or have an anxious personality, the amygdala might be activated by a frightening image. But hungry people have increased amygdala activity in response to pictures of food and people who are very empathetic have an amygdala response to seeing other people.

“When we’re studying emotion, people want to find specific brain parts that are associated with different

emotions,” Cunningham says. Especially in the early days of neuroscience, scientists hoped that soon it would be possible to use MRI and other brain-imaging techniques “to get under the hood and find out what people are really thinking.” A lot of the time, people really don’t know, or won’t say, what they’re thinking, and it would be nice to be able to look at a picture of their brain and know the answer. But the brain is too complicated for that. Cunningham also thinks many scientists have gotten too attached to a rigid definition of emotions—anger, fear, sadness, happiness, and so on.

However you may feel, it seems that many different parts of the brain are involved. ”Emotion is going to be distributed across the brain,” Cunningham says.

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Methylene Blue Studied for Bipolar as FDA Issues Warning

Methylene blue By Kenneth J. Bender, PharmD, MA | October 5, 2011

A study presented by Canadian investigators at the 24th Congress of the European College of Neuropsychopharmacology (ECNP) in Paris, September 5 evaluated whether methylene blue can reduce residual symptoms of depression and mania in bipolar disorder.1

Weeks before, on July 26, the FDA issued a safety warning on the risk of serotonin syndrome when methylene blue is given concurrently with serotonergic psychiatric medications;2 and Health Canada issued a similar warning in February.

The compound is better known as a treatment for methemoglobinemia and as a dye in diagnostic applications, but it is also a potent, reversible monoamine oxidase inhibitor. Its potential to improve symptoms in bipolar disorder arises from other, possibly neuroprotective mechanisms including inhibition of nitric oxide synthase and guanylate cyclase, according to investigator Martin Alda, MD and colleagues, Dalhousie University, Halifax, Nova Scotia.

The investigators administered methylene blue to 37 subjects meeting criteria for bipolar disorder, while maintaining lamotrigine(Drug information on lamotrigine) as their primary mood stabilizer. Patients were randomized to receive 13 weeks treatment with either 195 mg methylene blue daily, or 15 mg as a putative subtherapeutic dose in lieu of a placebo that mimics the color in urine; with groups switching the regimen for an additional 13 weeks.

Alda reported that the active dose was associated with statistically significantly improved mood symptom scores from baseline on multiple measures, including the Montgomery-Asberg Depression Rating Scale (MADRS). There was no therapeutic effect apparent on cognitive performance, but no decrement observed with its use.

The compound was generally well tolerated in this controlled population, but this use remains investigational and, as the FDA warns, “methylene blue should generally not be given to patients taking serotonergic drugs unless the benefit is deemed to outweigh the risk.”

References

1. Alda M, MacQueen G, McKinnon M, et al. Methylene blue for residual symptoms and for cognitive dysfunction in bipolar disorder: Results of a double-blind trial. Presented at the 24th Congress of the European College of Neuropsychopharmacology (ECNP), Paris, September 5, 2011. Abstract P.2.e.001.

2. FDA. Drug Safety Communication: Serious CNS reactions possible when methylene blue is given to patients taking certain psychiatric medications. July 26, 2011. http://www.fda.gov/Drugs/DrugSafety/ucm263190.htm. Accessed September 28, 2011.

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Nietzsche was right: adversity makes you stronger

It is the quote used by many to bolster resilience in the face of adversity. But the words “what does not kill me, makes me stronger”, by the German philosopher Friedrich Nietzsche, could have scientific merit too, according to research.

German philosopher Friedrich Nietzsche, 12:55 PM GMT 19 Dec 2011

Nietzsche

US psychologists found that while traumatic experiences such as assault, bereavement or natural disaster can be extremely damaging, smaller amounts of trauma may help people develop resilience. “Everybody’s heard the aphorism ‘whatever doesn’t kill you makes you stronger,’ ” Mark Seery, a researcher at the University at Buffalo, said. “But in psychology, a lot of ideas that seem like common sense aren’t supported by scientific evidence.

“Indeed, a lot of solid research shows that having miserable life experiences is bad for you.

“Serious events, like the death of a child or parent, a natural disaster, being physically attacked, experiencing sexual abuse, or being forcibly separated from your family, can cause psychological problems. Some research has suggested that the best way to go through life is having nothing ever happen to you.

But not only is that unrealistic, it’s not necessarily healthy.”

In one study, although researchers found that people who experienced lots of adversity were generally more distressed than others, those who had experienced no traumatic events in their lives had similar psychological problems.

The people with the best outcomes were those who had experienced some negative events in their lives.

Another study found that people with chronic back pain were able to get around better if they had experienced some serious adversity, whereas those who had suffered either large amounts of adversity, or none at all, were more impaired in life.

Dr Seery said one possibility for this pattern was that people who have been through traumatic experiences have had the opportunity to develop their coping mechanisms more acutely.

He said: “The idea is that negative life experiences can toughen people, making them better able to manage subsequent difficulties.”

Dr Seery also said people who have gone through stressful events may have stronger social networks than others, as they have learnt how to get help from others when they need it.

“I really look at this as being a silver lining,” he added.

“Just because something bad has happened to someone doesn’t mean they’re doomed to be damaged from that point on.”

Dr Seery’s paper on adversity and resilience was published in the latest issue of the journal Current Directions in Psychological Science.

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Psychopaths: Born evil or with a diseased brain?


Scans of serial killer Brian Dugan’s brain showed limited activity in the area processing emotions

When Brian Dugan pleaded guilty to the brutal rape and murder of a seven-year-old girl, Jeanine Nicarico, he seemed to be the very sketch of a brutal serial killer.

She had been murdered in 1983, though Dugan only pleaded guilty in 2009. By then, he had also been convicted of rape several times over, and the murder of two others – another seven-year-old girl and a 27-year-old nurse whom he ran off the road before raping and killing her.

If the death sentence had not been withdrawn in Illinois, Dugan would have been executed.

Yet strikingly, he showed no remorse for any of his murders or crimes. Scientists now believe this lack of empathy may in fact be linked to the reason he committed these acts.

Neuroscientist Dr Kent Kiehl of the University of New Mexico scanned Dugan’s brain, as part of a unique project to understand how anti-social behaviour is related to brain structure and function.

“He struggles to try and understand why people even care about what he did,” says Kiehl, describing his time interviewing Dugan. “Clinically, it is fascinating.”

Psychopathy
Dr Kiehl is seen as a pioneer in a cutting-edge area of behavioural neuroscience: the attempt to understand psychopaths’ brain functions and use this to develop treatments for their condition.

It is controversial because for thousands of years, men like Dugan have been labelled not as ill, but as evil.

In literature and cinema, the term “psychopath” is not used for a diagnosis for which we might have sympathy, but rather as something we might fear.

Dr Kiehl has a different view: “I tend to see psychopaths as someone suffering from a disorder, so I wouldn’t use the word evil to describe them.”

So what exactly is a psychopath?

“Clinically, we define it as someone who scores high on traits such as lack of empathy, guilt and remorse,” says Dr Kiehl.

“They are very impulsive: they tend not to plan or think before acting. They tend to get themselves in trouble by a very early age.”

We have long known that many people in prisons display symptoms of psychopathy, but until now we have had little insight into their condition.

Brain scans
To address that using neuroscience, Dr Kiehl’s lab has built a unique mobile brain scanner. It is equipped with the latest imaging technology but fitted into a truck he can drive into high-security prison facilities.

He used this to perform two types of analysis on Dugan’s brain: looking at its density and its function.

“Brian’s brain has very low levels of density in a system we call the para-limbic system,” he explains.

The para-limbic system is a “behaviour circuit” of the brain, including brain regions known as the amygdala and pre-frontal cortex.

Scientists have long known that these areas are associated with the processing of emotions.

Over the past century or so, people with brain damage to these areas have been studied because their behaviour suddenly changed and became anti-social.

“Those systems, we think, didn’t develop normally in Brian,” says Dr Kiehl. Psychopathy seems to involve a lack of development in these regions – which may be genetically determined.

Dr Kiehl also monitored Brian Dugan’s brain’s reaction to a number of distressing images, such as the faces of people suffering, which were displayed in front of him while he was in the scanner. By scanning his brain in real time, the aim was to test his brain’s function.

The scans showed there was relatively low activity in Dugan’s para-limbic system during processing of emotion.

“Brian would come out of the scanner during those studies and he said, wow, I had problems trying to process what you wanted me to do,” Dr Kiehl recounts. “He made more mistakes than others would.”

According to Dr Kiehl, it is part of a pattern of brain activity which proves that psychopaths simply lack an emotional ability, in much the same way others lack intellectual ability.

He has found similar results in large numbers of subjects, in prisons across the US.

This means Dugan simply has no concept of the harm he has caused. “Talking about his crimes, it’s like asking him what he had for breakfast,” says Dr Kiehl.

He also admits that in a sense, it is not surprising that the brain of somebody so different and anti-social also looks different from other brains. “But it’s only now that we can look at how dramatically different their brains are that people are starting to take notice,” he says.

“It has a very powerful influence on the legal system,” he adds.

Neuro-law
So what should the legal system do with this knowledge?

Research like Dr Kiehl’s has fuelled the debate over how much the legal system should change to accommodate what we now know about how bad behaviour is “hard-wired.”

This view of criminal law is often referred to as “neuro-law”.

It is a controversial vision of a future in which a moral judgement of criminal behaviour is replaced by a view that some criminals have diseased brains that need to be treated.

But Dr Kiehl does not see his work resulting in any change to the prosecution of violent psychopaths like Brian Dugan. Instead, he argues that understanding psychopathy may lead us to different types of sentencing – in particular an end to the death sentence for psychopaths.

“My hope is that the neuroscience helps the legal system to understand that these individuals have a disorder and this disorder is treatable,” he says.

Such treatment should not begin after someone has committed a terrible act, he says. Instead, he is working with other scientists to try and design interventions for children who display the same symptoms, before those symptoms escalate.

brain dugan
Brian Dugan showed no remorse for the crimes he committed, including rape and three murders

Treating children

He thinks Dugan’s life story shows key moments when interventions could have been made. “Brian suffered at a very early age,” says Dr Kiehl. “He did classic things: he set fires, he hurt animals, he injured his brothers and sisters.”

Although Dugan was seen by specialist child services, they lacked an understanding of his condition. In fact, children who have symptoms linked to psychopathy often respond poorly to the kinds of techniques used with other badly behaved children.

Because they lack emotional capability, when teachers attempt to get them to feel remorse it may make them confused and more likely to hurt others.

The hope now is to develop a specific diagnosis for these children – callous and unemotional disorder – and to develop programmes and treatments specifically geared to their condition. In essence, these children have to be painstakingly taught reactions which the rest of us have automatically.

Dr Kiehl’s work in high security prisons is inspiring other labs, in the US and UK, who are working directly with children. “You could prevent those individuals like Brian from ever developing and escalating into the individual that he is today,” he says.

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Skilled readers rely on their brain’s ‘visual dictionary’ to recognize words

Christmas tree made from books. Skilled readers can recognize words at lightning fast speed when they read because the word has been placed in a visual dictionary of sorts, say Georgetown University Medical Center (GUMC) neuroscientists. The visual dictionary idea rebuts the theory that our brain “sounds out” words each time we see them.

This finding, reported at the annual meeting of the Society for Neuroscience, Neuroscience 2011, matters because unraveling how the brain solves the complex task of reading can help in uncovering the brain basis of reading disorders, such as dyslexia, say the scientists.

“One camp of neuroscientists believes that we access both the phonology and the visual perception of a word as we read them and that the area or areas of the brain that do one, also do the other, but our study proves this isn’t the case,” says the study’s lead investigator, Laurie Glezer, Ph.D., a postdoctoral research fellow. She works in the Laboratory for Computational Cognitive Neuroscience at GUMC, led by Maximilian Riesenhuber, Ph.D., who is a co-author.

“What we found is that once we’ve learned a word, it is placed in a purely visual dictionary in the brain. Having a purely visual representation allows for the fast and efficient word recognition we see in skilled readers,” she says. “This study is the first demonstration of that concept.”

Glezer says that these findings might help explain why people with dyslexia have slower, more labored reading. “It could be that in dyslexia, because of phonological processing problems, these individuals are not ever able to develop a finely tuned visual representation of the words they have encountered before,” she says. “They can’t take advantage of the fast processing of words using this dictionary.”

Glezer and her co-authors tested word recognition in 12 volunteers using fMRI. They were able to see that words that are different, but sound the same, like “hare” and “hair” activate different neurons, akin to accessing different entries in a dictionary’s catalogue. “If the sounds of the word had influence in this part of the brain we would expect to see that they activate the same or similar neurons, but this was not the case, ‘hair’ and ‘hare’ looked just as different as “hair” and “soup”. This suggests that all we use is the visual information of a word and not the sounds.”

“When we see a word for the first time, it requires some time to read and sound it out, but after perhaps just one presentation of the word, you can recognize it without sounding it out,” she says. “This occurs because our brain first uses phonology to encode the word and match the sound with the written word. Once we do that and encounter the word a few more times, we no longer need the phonology at first, just the visual input to identify the word.”

“We hope these findings will serve as a foundation to examine reading disorders,” Glezer says. “For example, if people with dyslexia have a problem forming this visual dictionary, it may be that there could be ways of helping train children with dyslexia to form a more finely tuned visual dictionary.”

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‘Magic Mushrooms’ Trigger Lasting Personality Change

Bill Hicks

The psychedelic drug psilocybin (the active ingredient in “magic mushrooms”) may produce lasting, positive changes in personality, new research finds. People who took the drug showed increases in the key personality dimension of openness — being amenable to new ideas, experiences and perspectives — more than a year later.

“It was sort of like an anti-inflammatory for the ego,” says Brian, a 50-year-old scientist, who participated in the research (he declined to reveal his last name). “The swelling went down and I got to see what was underneath.”

Researchers led by Katherine MacLean, a postdoctoral student at Johns Hopkins University, analyzed personality data on 52 participants (average age 46) who had participated in the group’s earlier research on the drug. These volunteers took psilocybin during two to five sessions, at various doses, under highly controlled conditions at the hospital. They were also given personality tests before taking psilocybin, again a couple of months after each drug session, then again about a year later.

The earlier study had found positive psychological changes — documented by both participants and their family members and other associates — in calmness, happiness and kindness. The new research found that the drug takers also saw long-term changes to their underlying personality. “The most surprising thing was that we found a change in personality that is really not expected in healthy adults, not after such a discrete event,” says MacLean.

MORE: ‘Magic Mushrooms’ Can Improve Psychological Health Long Term

While other research has found that some therapies, including intensive meditation, effective treatment with antidepressants or dialectical behavioral therapy to treat borderline personality disorder, can change adult personality, lasting positive change has never been documented as a result of just a few doses of a drug.

The personality changes also ran counter to those expected as people age. Normally, as people grow older, they become increasingly less open to new ideas and new experiences. In contrast, in participants who experienced had what researchers call a “full mystical experience,” the scientists saw a shift toward increased openness, as though the volunteers had become decades younger.

People became more curious and more interested in new ideas and experiences and in trying new things. “It ended up being the best experience of my life,” says 67-year-old retiree Maria Estevez. “It was marvelous, radiant. I felt like I was coming into a magnificent palace, expansive and joyous.”

Those who didn’t have a full mystical experience showed no personality change, however. The researchers defined full mystical experiences as those that engendered the sense that “all is one” and that everything is connected, an experience of having transcended time and space, a sense of sacredness and peace and an inability to describe accurately the experience in words.

Brian’s mushroom trip was exactly that. But it didn’t happen during his first drug session. For his first dose, he had been randomly assigned to get placebo, so he simply sat blindfolded, listening to classical music through headphones in a calm, elegant room attended by a study monitor, whom Brian had met with over the several preceding weeks to prepare for the experiment. “Four hours went by and nothing really happened,” he says.

Meanwhile, Estevez had the opposite initial experience. She was randomized to receive the highest possible dose first, which ended up being the worst experience of her life. “I was slammed, I was inundated, I felt like I was drowning,” she says. “I was knocked around and tumbling beyond all sanity.”

The monitors helped her through it, but she still considered dropping out. She reconsidered after realizing that she might never get another chance to have a better psychedelic experience. Estevez had originally learned about the study in a classified ad, a day after she’d re-read Aldous Huxley’s famous account of his mescaline experience, and wished she could try something similar for her own spiritual exploration.

Indeed, many of the participants in the experiment were self-motivated to enroll, out of curiosity about the effects of magic mushrooms or because they too wanted the opportunity to self-reflect. Many participants already engaged in spiritual activities like meditation, religious services and prayer. That may help explain why they were so sensitive to the effects of the drug, the researchers acknowledged.

MORE: More Evidence That Marijuana-Like Drugs May Help Prevent PTSD

Brian had always been a deeply spiritual man. He had recently been drawn to Eastern religions and the notion that the separation of our selves from the rest of the world was illusory, and said he signed up for the study because he was curious. He jokes that he hadn’t tried psychedelics earlier because “I was actually a victim of my own good judgment in my youth.”

During his experience with a higher dose of psilocybin, he says, “I was just able to drop ego totally and experience the world without all those filters, and experience Brian without all that.”

He describes his experience on the highest possible dose of psilocybin this way:

There was this point where, basically, I forgot about anything Brian-like or who Brian was. I was really in touch with all experience: whatever happened was part of me. I was not observing — I was whatever was happening. The other thing that was so memorable was that everything was so beautiful and it made me cry because the beauty was so exquisite. And then I’d remember how painful and how messy it all was. I was laughing and crying for like three hours straight.
I was absolutely that certain that everything was just the same thing, just different flavors and tastes of one underlying reality and being so grateful to be alive and able to experience it.
Brian says that this recognition made him more tolerant and more compassionate. “What was happening to me was real and [yet] the person next to me might not be seeing the same thing. It became absolutely obvious that perspective determines your experience with reality and that maybe being able to take more perspectives than one will give you a more rich and probably more true version of what reality is.”

MORE: here for more info.) The scientists ultimately hope to be able to use psychedelics in treatments for mental illness and to study the nature of consciousness itself.

The new research was published in the Journal of Psychopharmacology.

Updated: The original post did not include the full title of the journal in which the research appeared.

Maia Szalavitz is a health writer for TIME.com. Find her on Twitter at @maiasz. You can also continue the discussion on TIME Healthland‘s Facebook page and on Twitter at @TIMEHealthland.

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Does Coffee Boost Brain/ Cognitive Functions Over Time?

energetic coffee cup

 

A few eter­nal ques­tions:

– Is caf­feine good for the brain?
– Does it boost cog­ni­tive func­tions?
– Does it pro­tect against dementia?

There is lit­tle doubt that drink­ing that morn­ing cup of cof­fee will likely increase alert­ness, but the main ques­tions that research is try­ing to answer go beyond that. Basi­cally: is there a sus­tained, life­time, ben­e­fit or harm from drink­ing cof­fee regularly?

The answer, so far, con­tains good news and bad news. The good news for cof­fee drinkers is that most of the long-term results are direc­tion­ally more pos­i­tive than neg­a­tive, so no clear harm seems to occur. The bad news is that it is not clear so far whether caf­feine has ben­e­fi­cial effects on gen­eral brain func­tions, either short-term or long-term (aged-related decline or risks of dementia).

It is impor­tant to note that many of the stud­ies show­ing an effect of cof­fee con­sump­tion on brain func­tions or risks of demen­tia report a cor­re­la­tion or asso­ci­a­tion (they are not ran­dom­ized clin­i­cal tri­als). As you know, cor­re­la­tion doesn’t prove cau­sa­tion: cof­fee drinkers may seem to do well in a num­ber in these long-term stud­ies, but there may be other rea­sons why cof­fee drinkers do better.

Q: How does caf­feine affect my brain?

A: Caf­feine is a stimulant.

It belongs to a chem­i­cal group called xan­thine. Adeno­sine is a nat­u­rally occur­ring xan­thine in the brain that slows down the activ­ity of brain cells (neu­rons). To a neu­ron, caf­feine looks like adeno­sine. It is there­fore used by some neu­rons in place of adeno­sine. The result is that these neu­rons speed up instead of slow­ing down.

This increased neu­ronal activ­ity trig­gers the release of the adren­a­line hor­mone, which will affect your body in sev­eral ways: your heart­beat increases, your blood pres­sure rises, your breath­ing tubes open up, sugar is released in the blood­stream for extra energy.

In mod­er­ate doses (a few cups a day) caf­feine can increase alert­ness but also reduce fine motor coor­di­na­tion, cause insom­nia, cause headaches and nervousness.

Q: Does caf­feine boost brain functions?

A: To date 3 stud­ies sug­gest that the answer is “maybe”.

In one study of over 7000 peo­ple, results showed a cor­re­la­tion between cur­rent caf­feine intake and bet­ter per­for­mance on 4 tests. This was more pro­nounced in older indi­vid­u­als than in younger ones (Mar­tin, 1993).

Another study showed that in 1500 peo­ple over 65, life-time con­sump­tion of cof­fee was asso­ci­ated with increased per­for­mance in 6 out 12 tests. Cur­rent intake was related to bet­ter per­for­mance in only 2 out 12 tests (Johnson-Kozlow, et al., 2002).

The third study showed for a group of 1875 adults aged 24 to 81, cur­rent intake of cof­fee was asso­ci­ated with bet­ter per­for­mance in 2 tests but not in 4 oth­ers. (Hameleers et al., 2000)

Thus, caf­feine con­sump­tion may be asso­ci­ated with bet­ter per­for­mance but 1) there are only very few stud­ies so far, 2) this effect seems lim­ited to some tasks only.

Q: Does caf­feine pro­tect against age-related cog­ni­tive decline?

A: Two stud­ies say “yes” and 3 stud­ies say “no”.

Van Gelder et al. (2007) fol­lowed 676 elderly men over 10 years and found that those who drank more cof­fee showed less decline in the Mini-Mental Test. The least decline was observed with 3 cups a day.

Ritchie et al. (2007) showed that over 4 years, women over 65 (but not men) who drank more than 3 cups a day showed less decline than women who drank one cup or less. This was observed only in a task of ver­bal memory.

Van Box­tel et al. (2003) fol­lowed 1376 indi­vid­u­als aged 24 to 81 for 6 years and found that caf­feine intake had a very small impact on a motor task but no effect on ver­bal mem­ory tasks.

Hameleers et al. (2000) found no evi­dence that caf­feine intake coun­ter­acts cog­ni­tive age-related decline in a group of 1875 peo­ple aged 24 to 81.

The most recent study of 2606 peo­ple showed that over 28 years cof­fee drink­ing was not related to bet­ter per­for­mance (Laitala et al., 2009).

As you can see results are mixed. The evi­dence show­ing that caf­feine reduces age-related cog­ni­tive decline is lim­ited: very few stud­ies and very few tasks.

Q: Does caf­feine pro­tect against dementia?

A: Three stud­ies say “yes” and 2 stud­ies say “no”.

Maia et al. (2002) stud­ied 54 Alzheimer’s patients and their non-affected rel­a­tives (Con­trols): Higher daily caf­feine intake dur­ing the 20 years prior diag­no­sis was found to be asso­ci­ated with lower risk of Alzheimer’s Dis­ease, sug­gest­ing that cof­fee may be protective.

Eske­li­nen et al. (2009) fol­lowed 1409 indi­vid­u­als aged 65 to 79 for 21 years and found that those who drank cof­fee had less risk of devel­op­ing demen­tia than those who didn’t. The low­est risk was in peo­ple drink­ing 3–5 cups a day.

Lind­say et al (2002) stud­ied 4615 indi­vid­u­als over 5 years and found that cof­fee con­sump­tion was asso­ci­ated with a reduced risk of Alzheimer’s Disease.

Ritchie et al. (2007) stud­ied 7017 indi­vid­u­als aged 65 and over and showed that, over 4 years, caf­feine con­sump­tion did not reduce demen­tia risk.

The most recent study to date showed that over 28 years, cof­fee drink­ing did not affect the risk of mild cog­ni­tive impair­ment or demen­tia (Laitala et al., 2009).

Here again the evi­dence is mixed. Based on the few stud­ies, it is not pos­si­ble at this time to say that cof­fee con­sump­tion indeed decreases the risks of dementia.

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Brain Scans Can See What You See

New fmri scans can see what you see.Mind-reading has always been a fantastical feat, possible only in fictional realms such as Marvel Comics (X-Men‘s psychics Professor X and Jean Grey), Madeleine L’Engle’s A Wind in the Door, or Robert A. Heinlein’s Stranger in a Strange Land. However, technology is advancing rapidly, and since the advent of brain scanning techniques such as fMRI–which, for those who are unfamiliar with the term, stands for “functional Magnetic Resonance Imaging” and works by showing blood flow to different areas of the brain–humans have come progressively closer to creating technology that can peer inside their own minds.

Until recently, the most researchers have been able decode is stationary objects–such as when subjects viewed an image of a tree. This is due to the fact that fMRI detects blood flow, which moves slowly compared to the fast-paced neural activity that happens when a subject views moving images.

However, in a study recently published in Current Biology,1 researchers at the University of California demonstrated that by using a complex computer program that filled the gaps in data to approximate fast-paced neural activity, they were able to recreate elements of moving visual scenes from fMRI data.

In their experiment, the researchers stuck subjects in fMRI machines and had them watch hours of Hollywood movie trailers. The fMRI output then feeds into the aforementioned computer program, which used the data to learn how each person’s visual system responded to the movie scenes. Finally, the researchers took the brain signals by themselves and successfully recreated what the subjects had been watching.

The implications for this research? Imagination. Dreams. Imagine being able to look into your own subconscious. Now, imagine a machine telling you exactly what just went through your head. That is the technology that is on the way.

 

1.Nishimoto, S., Vu, A., Naselaris, T., Benjamini, Y., Yu, B., & Gallant, J. (2011). Reconstructing Visual Experiences from Brain Activity Evoked by Natural Movies Current Biology, 21 (19), 1641-1646 DOI: 10.1016/j.cub.2011.08.031

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