Archive for the ‘neurologist’ Category

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Talking to yourself used to be a strictly private pastime. That’s no longer the case – researchers have eavesdropped on our internal monologue for the first time. The achievement is a step towards helping people who cannot physically speak communicate with the outside world.

“If you’re reading text in a newspaper or a book, you hear a voice in your own head,” says Brian Pasley at the University of California, Berkeley. “We’re trying to decode the brain activity related to that voice to create a medical prosthesis that can allow someone who is paralysed or locked in to speak.”

When you hear someone speak, sound waves activate sensory neurons in your inner ear. These neurons pass information to areas of the brain where different aspects of the sound are extracted and interpreted as words.

In a previous study, Pasley and his colleagues recorded brain activity in people who already had electrodes implanted in their brain to treat epilepsy, while they listened to speech. The team found that certain neurons in the brain’s temporal lobe were only active in response to certain aspects of sound, such as a specific frequency. One set of neurons might only react to sound waves that had a frequency of 1000 hertz, for example, while another set only cares about those at 2000 hertz. Armed with this knowledge, the team built an algorithm that could decode the words heard based on neural activity alone (PLoS Biology, doi.org/fzv269).

The team hypothesised that hearing speech and thinking to oneself might spark some of the same neural signatures in the brain. They supposed that an algorithm trained to identify speech heard out loud might also be able to identify words that are thought.

Mind-reading

To test the idea, they recorded brain activity in another seven people undergoing epilepsy surgery, while they looked at a screen that displayed text from either the Gettysburg Address, John F. Kennedy’s inaugural address or the nursery rhyme Humpty Dumpty.

Each participant was asked to read the text aloud, read it silently in their head and then do nothing. While they read the text out loud, the team worked out which neurons were reacting to what aspects of speech and generated a personalised decoder to interpret this information. The decoder was used to create a spectrogram – a visual representation of the different frequencies of sound waves heard over time. As each frequency correlates to specific sounds in each word spoken, the spectrogram can be used to recreate what had been said. They then applied the decoder to the brain activity that occurred while the participants read the passages silently to themselves.

Despite the neural activity from imagined or actual speech differing slightly, the decoder was able to reconstruct which words several of the volunteers were thinking, using neural activity alone (Frontiers in Neuroengineering, doi.org/whb).

The algorithm isn’t perfect, says Stephanie Martin, who worked on the study with Pasley. “We got significant results but it’s not good enough yet to build a device.”

In practice, if the decoder is to be used by people who are unable to speak it would have to be trained on what they hear rather than their own speech. “We don’t think it would be an issue to train the decoder on heard speech because they share overlapping brain areas,” says Martin.

The team is now fine-tuning their algorithms, by looking at the neural activity associated with speaking rate and different pronunciations of the same word, for example. “The bar is very high,” says Pasley. “Its preliminary data, and we’re still working on making it better.”

The team have also turned their hand to predicting what songs a person is listening to by playing lots of Pink Floyd to volunteers, and then working out which neurons respond to what aspects of the music. “Sound is sound,” says Pasley. “It all helps us understand different aspects of how the brain processes it.”

“Ultimately, if we understand covert speech well enough, we’ll be able to create a medical prosthesis that could help someone who is paralysed, or locked in and can’t speak,” he says.

Several other researchers are also investigating ways to read the human mind. Some can tell what pictures a person is looking at, others have worked out what neural activity represents certain concepts in the brain, and one team has even produced crude reproductions of movie clips that someone is watching just by analysing their brain activity. So is it possible to put it all together to create one multisensory mind-reading device?

In theory, yes, says Martin, but it would be extraordinarily complicated. She says you would need a huge amount of data for each thing you are trying to predict. “It would be really interesting to look into. It would allow us to predict what people are doing or thinking,” she says. “But we need individual decoders that work really well before combining different senses.”

http://www.newscientist.com/article/mg22429934.000-brain-decoder-can-eavesdrop-on-your-inner-voice.html

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The many documented cases of strange delusions and neurological syndromes can offer a window into how bizarre the brain can be.

It may seem that hallucinations are random images that appear to some individuals, or that delusions are thoughts that arise without purpose. However, in some cases, a specific brain pathway may create a particular image or delusion, and different people may experience the same hallucination.

In recent decades, with advances in brain science, researchers have started to unravel the causes of some of these conditions, while others have remained a mystery.

Here is a look at seven odd hallucinations, which show that anything is possible when the brain takes a break from reality.

1. Alice-in-Wonderland syndrome
This neurological syndrome is characterized by bizarre, distorted perceptions of time and space, similar to what Alice experienced in Lewis Carroll’s “Alice’s Adventures in Wonderland.”

Patients with Alice-in-Wonderland syndrome describe seeing objects or parts of their bodies as smaller or bigger than their actual sizes, or in an altered shape. These individuals may also perceive time differently.

The rare syndrome seems to be caused by some viral infections, epilepsy, migraine headaches and brain tumors. Studies have also suggested that abnormal activity in parts of the visual cortex that handle information about the shape and size of objects might cause the hallucinations.

It’s also been suggested that Carroll himself experienced the condition during migraine headaches and used them as inspiration for writing the tale of Alice’s strange dream.

English psychiatrist John Todd first described the condition in an article published in the Canadian Medical Association Journal in 1955, and that’s why the condition is also called Todd’s syndrome. However, an earlier reference to the condition appears in a 1952 article by American neurologist Caro Lippman. The doctor describes a patient who reported feeling short and wide as she walked, and referenced “Alice’s Adventures in Wonderland” to explain her body image illusions.

2. Walking Corpse Syndrome
This delusion, also called Cotard’s Syndrome, is a rare mental illness in which patients believe they are dead, are dying or have lost their internal organs.

French neurologist Jules Cotard first described the condition in 1880, finding it in a woman who had depression and also symptoms of psychosis. The patient believed she didn’t have a brain or intestines, and didn’t need to eat. She died of starvation.

Other cases of Cotard’s syndrome have been reported in people with a range of psychiatric and neurological problems, including schizophrenia, traumatic brain injury and multiple sclerosis.

In a recent case report of Cotard’s syndrome, researchers described a previously healthy 73-year-old woman who went to the emergency room insisting that she was “going to die and going to hell.” Eventually, doctors found the patient had bleeding in her brain due to a stroke. After she received treatment in the hospital, her delusion resolved within a week, according to the report published in January 2014 in the journal of Neuropsychiatry.

3. Charles Bonnet syndrome
People who have lost their sight may develop Charles Bonnet syndrome, which involves having vivid, complex visual hallucinations of things that aren’t really there.

People with this syndrome usually hallucinate people’s faces, cartoons, colored patterns and objects. It is thought the condition occurs because the brain’s visual system is no longer receiving visual information from the eye or part of the retina, and begins making up its own images.

Charles Bonnet syndrome occurs in between 10 and 40% of older adults who have significant vision loss, according to studies.

4. Clinical lycanthropy
In this extremely rare psychiatric condition, patients believe they are turning into wolves or other animals. They may perceive their own bodies differently, and insist they are growing the fur, sharp teeth and claws of a wolf.

Cases have also been reported of people with delusional beliefs about turning into dogs, pigs, frogs and snakes.

The condition usually occurs in combination with another disorder, such as schizophrenia, bipolar disorder or severe depression, according to a review study published in the March issue of the journal History of Psychiatry in 2014.

5. Capgras delusion
Patients with Capgras delusion believe that an imposter has replaced a person they feel close to, such as a friend or spouse. The delusion has been reported in patients with schizophrenia, Alzheimer’s disease, advanced Parkinson’s disease, dementia and brain lesions.

One brain imaging study suggested the condition may involve reduced neural activity in the brain system that processes information about faces and emotional responses.

6. Othello syndrome
Named after Shakespeare’s character, Othello syndrome involves a paranoid belief that the sufferer’s partner is cheating. People with this condition experience strong obsessive thoughts and may show aggression and violence.

In one recent case report, doctors described a 46-year-old married man in the African country Burkina Faso who had a stroke, which left him unable to communicate and paralyzed in half of his body. The patient gradually recovered from his paralysis and speaking problems, but developed a persistent delusional jealousy and aggression toward his wife, accusing her of cheating with an unidentified man.

7. Ekbom’s syndrome
Patients with Ekbom’s syndrome, also known as delusional parasitosis or delusional infestations, strongly believe they are infested with parasites that are crawling under their skin. Patients report sensations of itching and being bitten, and sometimes, in an effort to get rid of the pathogens, they may hurt themselves, which can result in wounds and actual infections.

It’s unknown what causes these delusions, but studies have linked the condition with structural changes in the brain, and some patients have improved when treated with antipsychotic medications.

http://www.livescience.com/46477-oddest-hallucinations.html

They say laughter is the best medicine. But what if laughter is the disease?

For a 6-year-old girl in Bolivia who suffered from uncontrollable and inappropriate bouts of giggles, laughter was a symptom of a serious brain problem. But doctors initially diagnosed the child with “misbehavior.”

“She was considered spoiled, crazy — even devil-possessed,” Dr. José Liders Burgos Zuleta, ofAdvanced Medical Image Centre, in Bolivia, said in a statement.

But Burgos Zuleta discovered that the true cause of the girl’s laughing seizures, medically called gelastic seizures, was a brain tumor.

After the girl underwent a brain scan, the doctors discovered a hamartoma, a small, benign tumor that was pressing against her brain’s temporal lobe.The doctors surgically removed the tumor, and the girl is now healthy, the doctors said.

The girl stopped having the uncontrollable attacks of laughter and now only laughs normally, the doctors said.

Gelastic seizures are a form of epilepsy that is relatively rare, said Dr. Solomon Moshé, a pediatric neurologist at Albert Einstein College of Medicine in New York. The word comes from the Greek word for laughter, “gelos.”

“It’s not necessarily ‘hahaha’ laughing,” Moshé told Live Science. “There’s no happiness in this. Some of the kids may be very scared,” he added.

The seizures are most often caused by tumors in the hypothalamus, especially in kids, although they can also come from tumors in other parts of brain, Moshé said. Although laughter is the main symptom, patients may also have outbursts of crying.

These tumors can cause growth abnormalities if they affect the pituitary gland, he said.

The surgery to remove such brain tumors used to be difficult and dangerous, but a new surgical technique developed within the last 10 years allows doctors to remove them effectively without great risk, Moshé said.

The doctors who treated the girl said their report of her case could raise awareness of the strange condition, so doctors in Latin America can diagnose the true cause of some children’s “behavioral” problems, and refer them to a neurologist.

The case report was published June 16 in the journal ecancermedicalscience.

Thanks to Michael Moore for sharing this with the It’s Interesting community.

http://www.cbsnews.com/news/girls-uncontrollable-laughter-caused-by-brain-tumor/

Cynics are three times more likely to develop dementia than those who have faith in humanity, a study has shown.

Believing that others are motivated by selfishness, or that they lie to get what they want, appears to radically increase the risk of cognitive decline in later life.

It could mean that grumpy old men and women should be screened more closely for diseases such as Alzheimer’s. Cynicism has previously been linked to health problems such as heart disease, but this is the first time it has been associated with dementia.

“These results add to the evidence that people’s view on life and personality may have an impact on their health,” said Dr. Anna-Maija Tolppanen, the lead researcher at the University of Eastern Finland, whose study is published online in the journal Neurology.

Academics asked nearly 1,500 people with an average age of 71 to fill out a questionnaire to measure their levels of cynicism.

They were asked how much they agreed with statements such as “I think most people would lie to get ahead”, “it is safer to trust nobody” and “most people will use somewhat unfair reasons to gain profit or an advantage rather than lose it.”

Those taking part were monitored for eight years, during which time 46 of them were diagnosed with dementia. The academics discovered that those who had scored highly for cynicism were three times more likely to have developed dementia than those with low scores.

Researchers adjusted the results for other factors that could affect the risk of dementia, such as high blood pressure, high cholesterol and smoking.

Of the 164 people with high levels of cynicism, 14 people developed dementia, compared with nine of the 212 people with low levels of cynicism.

One in three people over 65 will develop a form of dementia. Of the 800,000 people in the U.K. who have the condition, more than half have Alzheimer’s disease. It is estimated that 1.7 million Britons will suffer from dementia by 2051.

Responding to the study findings, charities cautioned that the early symptoms of Alzheimer’s and dementia could make people more cynical about life.

Dr. Doug Brown, of the Alzheimer’s Society, said: “While this research attempts to make a link between higher levels of cynical distrust and risk of dementia, there were far too few people in this study that actually developed dementia to be able to draw any firm conclusions.

http://news.nationalpost.com/2014/05/28/being-a-cynic-linked-to-tripled-risk-of-developing-dementia-finland-study-suggests/

Thanks to Kebmodee for bringing this to the attention of the It’s Interesting community.

Pedophiles’ brains are “abnormally tuned” to find young children attractive, according to a new study published this week. The research, led by Jorge Ponseti at Germany’s University of Kiel, means that it may be possible to diagnose pedophiles in the future before they are able to offend.

The findings, published in scientific journal Biology Letters, discovered that pedophiles have the same neurological reaction to images of those they find attractive as those of people with ordinary sexual predilections, but that all the relevant cerebral areas become engaged when they see children, as opposed to fellow adults. The occipital areas, prefrontal cortex, putamen, and nucleus caudatus become engaged whenever a person finds another attractive, but the subject of this desire is inverted for pedophiles.

While studies into the cognitive wiring of sex offenders have long been a source of debate, this latest research offers some fairly conclusive proof that there is a neural pattern behind their behavior.

The paper explains: “The human brain contains networks that are tuned to face processing, and these networks appear to activate different processing streams of the reproductive domain selectively: nurturing processing in the case of child faces and sexual processing in the case of sexually preferred adult faces. This implies that the brain extracts age-related face cues of the preferred sex that inform appropriate response selection in the reproductive domains: nurturing in the case of child faces and mating in the case of adult faces.”

Usually children’s faces elicit feelings of caregiving from both sexes, whereas those of adults provide stimuli in choosing a mate. But among pedophiles, this trend is skewed, with sexual, as opposed to nurturing, emotions burgeoning.

The study analyzed the MRI scans of 56 male participants, a group that included 13 homosexual pedophiles and 11 heterosexual pedophiles, exposing them to “high arousing” images of men, women, boys, and girls. Participants then ranked each photo for attractiveness, leading researchers to their conclusion that the brain network of pedophiles is activated by sexual immaturity.

The critical new finding is that face processing is also tuned to face cues revealing the developmental stage that is sexually preferred,” the paper reads.

Dr. James Cantor, associate professor at the University of Toronto’s Faculty of Medicine, said he was “delighted” by the study’s results. “I have previously described pedophilia as a ‘cross-wiring’ of sexual and nurturing instincts, and this data neatly verifies that interpretation.”

Cantor has undertaken extensive research into the area, previously finding that pedophiles are more likely to be left-handed, 2.3 cm shorter than the average male, and 10 to 15 IQ points lower than the norm.

He continued: “This [new] study is definitely a step in the right direction, and I hope other researchers repeat this kind of work. There still exist many contradictions among scientists’ observations, especially in identifying exactly which areas of the brain are the most central to pedophilia. Because financial support for these kinds of studies is quite small, these studies have been quite small, permitting them to achieve only incremental progress. Truly definitive studies about what in the brain causes pedophilia, what might detect it, and what might prevent it require much more significant support.”

Ponseti said that he hoped to investigate this area further by examining whether findings could be emulated when images of children’s faces are the sole ones used. This could lead to gauging a person’s predisposition to pedophilia far more simply than any means currently in place. “We could start to look at the onset of pedophilia, which is probably in puberty at about 12 or 14 years [old],” he told The Independent.

While Cantor is correct in citing the less than abundant size of the study, the research is certainly significant in providing scope for future practicable testing that could reduce the number of pedophilic crimes committed. By being able to run these tests and examine a person’s tendency toward being sexually attracted to underage children, rehabilitative care and necessary precautions could be taken to safeguard children and ensure that those at risk of committing a crime of this ilk would not be able to do so.

http://www.thedailybeast.com/articles/2014/05/23/study-finds-pedophiles-brains-wired-to-find-children-attractive.html#


Sol Snyder, Distinguished Service Professor of Neuroscience, Pharmacology and Psychiatry, School of Medicine

Growing up, I never had any strong interest in science. I did well in lots of things in high school. I liked reading philosophy and things like that, but being a philosopher is not a fit job for a nice Jewish boy.

This was in the mid-1950s, and many of my friends were going into engineering, preparatory to joining the then prominent military industrial complex. Others were going to be doctors, so I got the idea that maybe I’d be a psychiatrist. I didn’t have any special affinity for medicine or desire to cast out the lepers or heal mankind.

I was always reading things. My father valued education. He wasn’t a big advice giver, but he … had a lot of integrity. What was important to him was doing the right thing. And he had great respect for the intellectual life and science.

My father’s professional life commenced in 1935 as the 10th employee of what became the NSA. He led a team that broke one of the principal Japanese codes. At the end of World War II, computers were invented, and, if you think about it, what could be the best entity to take advantage of computers than NSA, with its mission of sorting gibberish and looking for patterns. So my father was assigned to look at these new machines and see if they would be helpful. He led the computer installations at NSA.

Summers in college I worked in the NSA. My father taught me to program computers in machine language. Computers were a big influence on me.

I learned at the NSA about keeping secrets. What is top secret, what is need-to-know—that is one of the things you learn in the business. You don’t talk to the guy at the next desk even if you’re working on the same project. If that person doesn’t need to know, you just shut up.

In medical school, I started working at the NIH in Bethesda during the summers and elective periods, largely because the only thing I really did well up to that time was play the classical guitar and one of my guitar students was an NIH researcher. In high school I thought I might go the conservatory route, but that’s even less fitting for a nice Jewish boy than being a philosopher.

It was through my contacts at NIH that I was able to get a position working with future Nobel Prize winner Julius Axelrod. Julie was a wonderful mentor who did research on drugs and neurotransmitters. Working with him was inspirational. I just adored it.

What was notable about Julie was his great creativity, always coming up with original ideas. Even though he was an eminent scientist, he didn’t have a regular office. He just had a desk in a lab. He did experiments with his own two hands every day.

Philosophically, Julie emphasized you go where the data takes you. Don’t worry that you’re an expert in enzyme X and so should focus on that. If the data point to enzyme Y, go for it. Do what’s exciting.

My very first project with Julie was studying the disposition of histamine. I thought I had found that histamine had been converted into a novel product that looked really interesting, and I was wrong. I missed the true product because we separated the chemicals on paper and discarded the radioactivity at the bottom, throwing away the real McCoy. Another lab at Yale found it, led, remarkably, by a close friend since kindergarten. My humiliation didn’t last very long. I learned not to be so sloppy, to take greater care, and, most important, to explore peculiar results.

How does one pick research directions? You can go where it’s “hot,” but there you’re competing with 300 other people, and everyone can make only incremental changes. But if you follow Julie Axelrod’s rules and you don’t worry about what’s hot, or what other people are doing—just go where your data are taking you—then you have a better chance of finding something that nobody else had found before.

With the discovery of the opiate receptor, I was fortunate to launch a new field: molecular identification of neurotransmitter receptors. Later we discovered that the gas nitrous oxide is a neurotransmitter.

I’m a klutz. I can’t hammer a nail. So for the technical side, like dissecting brains to look at different regions, I enlisted friends. I learned to collaborate, a key element in so many discoveries.

Johns Hopkins has always been a collegial place. People are just friendly and interact with each other. This tradition goes back to the founding of the medical school, permeating the school’s governance as well as research. We tend to be more productive than faculty at other schools, where one gets ahead by sticking an ice pick in the backs of colleagues.

One of my heroes was my guitar teacher, Sophocles Papas, Andrés Segovia’s best friend. Sophocles was an important influence in my life, and we stayed close until he died in his 90s. In a couple of years after commencing lessons, I was giving recitals, all thanks to him. Like Julie, Sophocles emphasized innovative short cuts to creativity.

I’ve remained involved with music. I’m the longest-serving trustee on the Baltimore Symphony Orchestra, chairing for many years its music committee. Trustees of arts organizations are typically businesspeople selected for their fundraising acumen. But the person who nominated me reportedly commented, I’d like to propose something radical: I’d like to propose a trustee who cares about music.

Most notable about psychiatry is that the major drugs—antipsychotics for schizophrenia, antidepressants, and anti-anxiety drugs—were all discovered in the mid-1950s. Subsequent tweaking has enhanced potency and diminished side effects, but there have been no major breakthroughs. No new class of drugs since 1958—rather frustrating.

As biomedical science advances, especially with the dawn of molecular biology, our power to innovate is just dazzling. Today’s students take all of this for granted, but those of us who have been doing research for several decades are daily amazed by our abilities to probe the mysteries of life.

The logic of nature is elegant and straightforward. The more we learn about how the body works, the more we are amazed by its beauty and inherent simplicity.

One of my pet peeves is that the very power of modern science leads journal and grant reviewers to expect every “i” dotted and every “t” crossed. Because of this, four years or more of work go into each scientific manuscript. Then, editors and reviewers of journals are so picayune that revising a paper consumes another year.

Now let’s consider the poor post­doctoral fellow or graduate student. To move forward in his or her career requires at least one major publication—a five-year enterprise. If you only have one shot on goal, one paper in five years, your chances of success shrivel. The duration of PhD training and postdoctoral training is getting so long that from the entry point at graduate school to the time you’re out looking for a job as an assistant professor is easily 12, 15 years. Well, that is ridiculous. If you got paid $10 million at the end of this road, that would be one thing, but scientists earn less than most other professionals. We’re deterring the young smart people from going into science.

Biomedical researchers don’t work in a vacuum. They work with grad students and postdoctoral fellows, so being a good mentor is key to being a good scientist. Keep your students well motivated and happy. Have them feel that they are good human beings, and they will do better science.

The most important thing is that you value the integrity of each person. I ask my students all the time, What do you think? And this discussion turns into minor league psychotherapy. Ah, you think that? Tell me more. Tell me more.

The “stupidest” of the students here are smarter than me. It’s a pleasure to watch them emerge.

I see my life as taking care of other people. Although I didn’t go to medical school with any intelligent motivation, once I did, I loved being a doctor and trying to help people. And I love being a psychiatrist and trying to understand people, and I try to carry that into everything I do.

In medical research, all of us want to find the causes and cures for diseases. I haven’t found the cause of any disease, although with Huntington’s disease, we are making inroads. And, of course, being a pharmacologist, my métier is discovering drugs and better treatments.

My secret? I come to work every day, and I keep my own calendar. That way I have free time to just wander around the lab and talk to the boys and girls and ask them how it’s going. That’s what makes me happy.

Sol Snyder joined Johns Hopkins in 1965 as an assistant resident in Psychiatry and would later become the youngest full professor in JHU history. In 1978, he received the Albert Lasker Basic Medical Research Award for his role in discovering the brain’s opiate receptors. In 1980, he founded the School of Medicine’s Department of Neuroscience, which in 2006 was renamed the Solomon H. Snyder Department of Neuroscience.

http://hub.jhu.edu/gazette/2014/january-february/what-ive-learned-sol-snyder

http://en.wikipedia.org/wiki/Solomon_H._Snyder

Alzheimers_elderly_1665136c

In a first-of-its-kind study, researchers have developed a blood test for Alzheimer’s disease that predicts with astonishing accuracy whether a healthy person will develop the disease.

Though much work still needs to be done, it is hoped the test will someday be available in doctors’ offices, since the only methods for predicting Alzheimer’s right now, such as PET scans and spinal taps, are expensive, impractical, often unreliable and sometimes risky.

“This is a potential game-changer,” said Dr. Howard Federoff, senior author of the report and a neurologist at Georgetown University Medical Center. “My level of enthusiasm is very high.”

The study was published in Nature Medicine.

In the beginning, the researchers knew they wanted to find a blood test to detect Alzheimer’s but didn’t know what specifically to look for. Should they examine patients’ DNA? Their RNA? Or should they look for the byproducts of DNA and RNA, such as fats and proteins?

They decided to start with fats, since it was the easiest and least expensive. They drew blood from hundreds of healthy people over age 70 living near Rochester, New York, and Irvine, California. Five years later, 28 of the seniors had developed Alzheimer’s disease or the mild cognitive problems that usually precede it.

Scouring more than 100 fats, or lipids, for what might set this group apart, they found that these 28 seniors had low levels of 10 particular lipids, compared with healthy seniors.

To confirm their findings, the researchers then looked at the blood of 54 other patients who had Alzheimer’s or mild cognitive impairment. This group also had low levels of the lipids.

Overall, the blood test predicted who would get Alzheimer’s or mild cognitive impairment with over 90% accuracy.

“We were surprised,” said Mark Mapstone, a neuropsychologist at the University of Rochester Medical Center and lead author of the study. “But it turns out that it appears we were looking in the right place.”

The beauty of this test, Mapstone says, is that it caught Alzheimer’s before the patient even had symptoms, suggesting that the disease process begins long before people’s memories start failing. He says that perhaps the lipid levels started decreasing at the same time as brain cells started dying.

He and his team plan to try out this test in people in their 40s and 50s. If that works, he says, that would be the “holy grail,” because then researchers could try experimental drugs and treatments in a group that’s almost sure to get the disease. That would speed research along immensely.

Plus, people could get a heads up that they were probably destined to get Alzheimer’s. Although some people might not want to know that they’re destined for a horrible disease, others might be grateful for the warning.

Federoff said he would want to know whether he was on his way to getting the disease, even though there’s nothing he could do about it. He might want to take a family trip he’d been thinking about or might want to appoint a successor at work.

“I would make sure that things that are important to me get done,” he said.

But, Federoff added, others might not want to know they were about to get a devastating disease they were powerless to stop.

“I think it’s a very personal decision,” Federoff said. “It would have to be thought through on multiple dimensions. Patients and their families would have to be counseled.”

Other research teams are looking at other possible tests for Alzheimer’s. The need for a screening test of some kind for Alzheimer’s has never been greater: A report released last week says the disease claims the lives of perhaps a half a million Americans, making it nearly as deadly as heart disease and cancer.

If any of these tests work out — and that’s still an if — it would take years to make it to doctors’ offices, since the test would need to be validated by other labs and with larger groups of people. Thee test developed by the Georgetown and Rochester researchers, for example, was used mainly in white people, and it might not work as well with other groups.

Heather Snyder, a spokeswoman for the Alzheimer’s Association, said the study was well done but much work is still needed.

“It’s an interesting paper. It’s an intriguing study. But it is very preliminary,” she said.http://www.cnn.com/2014/03/09/health/alzheimers-blood-test/index.html?hpt=hp_t2