ScienceDaily (June 11, 2012) — An arsenal of Alzheimer’s research revealed at the Society of Nuclear Medicine’s 59th Annual Meeting indicates that beta-amyloid plaque in the brain not only is involved in the pathology of Alzheimer’s disease but may also precede even mild cognitive decline. These and other studies advance molecular imaging for the early detection of beta-amyloid, for which one product is now approved in the United States , as a major push forward in the race for better treatments.

"Diagnosis of Alzheimer’s disease can now be made when the patient first presents symptoms and still has largely preserved mental function," says Christopher Rowe, M.D., a lead investigator for the Australian Imaging, Biomarkers and Lifestyle study of aging (AIBL) and professor of nuclear medicine at Austin Hospital in Melbourne, Australia. "Previously there was an average delay of three years between consulting a doctor over memory concerns and the diagnosis of Alzheimer’s, as the diagnosis required the presence of dementia. When used as an adjunct to other diagnostic measures, molecular imaging can help lead to earlier diagnosis. This may give the patient several years to prepare for dementia while they still have control over their destiny."

According to the World Health Organization, Alzheimer’s disease affects an estimated 18 million people worldwide, and incidence of the disease is expected to double by the year 2025 to 34 million. The National Institute on Aging estimates that as many as 50 percent of Americans aged 85 or older are affected.

Alzheimer’s disease is a chronic and currently incurable neurodegenerative disease. Beta-amyloid burden can begin to build in the brain several years, if not more than a decade, before an individual shows any sign of dementia. Those who go on to develop Alzheimer’s disease not only lose their ability to remember their loved ones but also have difficulty with essential bodily functions such as breathing and swallowing in the late stages of disease.

In one study, researchers used a molecular imaging technique called positron emission tomography (PET), which images physiological patterns in the body. PET was combined with an imaging agent called F-18 florbetaben, which binds to amyloid in the brain. This and other PET agents are drawn to targets in the body and emit a positron signal that is picked up by a scanner. Here molecular imaging was performed in conjunction with clinical and neuropsychological testing in order to better understand the long-term effects of beta amyloid plaques in the brains of older individuals with mild cognitive impairment. Those of the 45 subjects in the study who showed high levels of imaging agent binding during imaging and atrophy of the hippocampus, the memory center, had an 80 percent chance of developing Alzheimer’s disease within two years, researchers said.

"Molecular imaging is proving to be an essential part of Alzheimer’s disease detection," says Rowe. "This and other amyloid imaging techniques will have an increasing role in the earlier and more accurate diagnosis of neurodegenerative conditions such as Alzheimer’s disease due to their ability to measure the actual underlying disease process."

Another AIBL study included 194 healthy participants, 92 people with mild cognitive impairment and 70 subjects with Alzheimer’s disease, and used another imaging agent called C-11 PiB (Pittsburgh compound B) with PET to gauge amyloid burden in the brain. Researchers showed that, in this study group, widespread amyloid plaque build-up preceded cognitive impairment, and those with extensive amyloid burden were at higher risk of cognitive decline.

This and another study mark two of the first studies of their kind focusing on beta amyloid in healthy subjects. In the other study, 137 adults with normal cognitive function aged 30 to 89 years were imaged using PET with F-18 florbetapir, now FDA-approved for the detection of beta amyloid plaques, as well as functional magnetic resonance imaging in order to explore how amyloid build-up affects connections in specific areas of the brain involved in cognition, namely the default mode and salience networks, which are responsible for different states of wakeful rest and alertness. Those with increased amyloid burden in these neural networks were prone to impaired cognitive performance.

"The effect of beta amyloid in healthy aging is of great interest since this protein is strongly associated with Alzheimer’s disease and may be predictive of the transition from mild cognitive impairment to Alzheimer’s disease," says Michael Devous, Sr., Ph.D., director of neuroimaging at the Alzheimer’s Disease Center at UT Southwestern Medical Center in Dallas, Texas. "Less is known about its impact on cognition in otherwise healthy aging individuals. In addition, brain connectivity in these areas is thought to be sensitive to early changes in brain function caused both by aging itself and by disease processes such as Alzheimer’s disease."

Another study assessed the PET imaging agent C-11 PiB for its ability to detect amyloid plaque in comparison to another imaging agent, 18-F fluorodeoxyglucose (F-18 FDG). The latter acts like glucose, the brain’s primary energy source, to map out the metabolic functioning of the brain. Results of the study showed C-11 PiB amyloid imaging to be a better means of evaluating amyloid patterns in the brain than F-18 FDG imaging. In addition, of the 100 healthy participants, 15 percent were shown to have some amyloid build-up when molecular imaging was performed.

"We are using state-of-the-art, noninvasive PET and MRI technologies to look at some of the earliest developments of Alzheimer’s disease onset in the brains of normal middle-aged people," says Guofan Xu, M.D., Ph.D., lead author of the study and research scientist at the department of nuclear medicine and radiology at the University of Wisconsin located in Madison. "With this we can evaluate whether pathological changes associated with Alzheimer’s disease are happening many years before onset of significant clinical symptoms."

No treatments are currently available to cure or prevent Alzheimer’s disease. With advances in molecular imaging to detect beta amyloid plaques, researchers have an important new tool that may bring the medical community one step closer to making therapies and vaccines a reality for the disease.

Source: Science Daily

June 11, 2012

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

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

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

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

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

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

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

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

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

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

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

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

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

Provided by University of Oregon

Source: medicalxpress.com

June 11, 2012

A new study shows that changes in walking speed in late life may signal the early stages of dementia known as mild cognitive impairment (MCI). The research is published in the June 12, 2012, print issue of Neurology, the medical journal of the American Academy of Neurology.

"In our study, we used a new technique that included installing infrared sensors in the ceilings of homes, a system designed to detect walking movement in hallways,” said study author Hiroko Dodge, PhD, with Oregon Health and Science University in Portland and a member of the American Academy of Neurology. “By using this new monitoring method, we were able to get a better idea of how even subtle changes in walking speed may correlate with the development of MCI.”

The study involved 93 people age 70 or older who lived alone. Of those, 54 participants had no cognitive impairment, 31 had non-memory related MCI and eight had memory-related MCI. Participants were given memory and thinking tests and had their walking speed monitored at their homes unobtrusively over a three-year period. Participants were placed in groups of slow, moderate or fast based on their average weekly walking speed and how much their walking speed fluctuated at home.

The study found that people with non-memory related MCI were nine times more likely to be slow walkers than moderate or fast walkers and the amount of the fluctuation in walking speed was also associated with MCI.

"Further studies need to be done using larger groups of participants to determine whether walking speed and its fluctuations could be a predictor of future memory and thinking problems in the elderly,” said Dodge. “If we can detect dementia at its earliest phases, then we can work to maintain people’s independence, provide treatments and ultimately develop ways to prevent the disease from developing. Our in-home monitoring approach has a lot of potential to be used for sustaining independence of the elderly.”

Provided by American Academy of Neurology

Source: medicalxpress.com

ScienceDaily (June 11, 2012) — According to the Anxiety and Depression Association of America, one in eight children suffers from an anxiety disorder. And because many anxious children turn into severely anxious adults, early intervention can have a major impact on a patient’s life trajectory. The understandable reluctance to use psychiatric medications when it comes to children means child psychologists are always searching for viable therapeutic alternatives.

Now Prof. Yair Bar-Haim of Tel Aviv University’s School of Psychological Sciences and his fellow researchers are pursuing a new method to address childhood anxiety. Based on a computer program, the treatment uses a technique called Attention Bias Modification (ABM) to reduce anxiety by drawing children away from their tendency to dwell on potential threats, ultimately changing their thought patterns. In its initial clinical trial, the program was as effective as medication and cognitive therapy for children — with several distinct advantages.

The results of the trial were reported in the American Journal of Psychiatry.

Computers instead of capsules

Children are comfortable with computers, explains Prof. Bar-Haim. And because of the potential side effects of medications or the difficulty in obtaining cognitive behavioral therapy, such as the need for highly trained professionals, it is good to have an alternative treatment method. ABM treatments can be disseminated over the Internet or administered by personnel who don’t have to be Ph.D.s. “This could be a game-changer for providing treatment,” he says.

Anxious individuals have a heightened sensitivity towards threats that the average person would ignore, a sensitivity which creates and maintains anxiety, says Prof. Bar-Haim. One of the ways to measure a patient’s threat-related attention patterns is called the dot-probe test. The patient is presented with two pictures or words, one threatening and one neutral. These words then disappear and a dot appears where one of the pictures or words had been, and the patient is asked to press a button to indicate the dot’s location. A fast response time to a dot that appears in the place of the threatening picture or word indicates a bias towards threat.

To turn this test into a therapy, the location of the dot target is manipulated to appear more frequently beneath the neutral word or picture. Gradually, the patient begins to focus on that stimulus instead, predicting that this is where the dot will appear — helping to normalize the attention bias pattern and reduce anxiety.

Prof. Bar-Haim and his colleagues enlisted the participation of 40 pediatric patients with ongoing anxiety disorders and divided them into three groups. The first received the new ABM treatment; the second served as a placebo group where the dot appeared equally behind threatening and neutral images; and the third group was shown only neutral stimuli. Patients participated in one session a week for four weeks, completing 480 dot probe trials each session.

The children’s anxiety levels were measured before and after the training sessions using interviews and questionnaires. In both the placebo group and neutral images group, researchers found no significant change in the patients’ bias towards threatening stimuli. However, in the ABM group, there were marked differences in the participants’ threat bias. By the end of the trial, approximately 33 percent of the patients in this group no longer met the diagnostic criteria for anxiety disorder.

New methods for personalized treatment

These indications of the method’s success in treating children warrant further investigation, says Prof. Bar-Haim. In collaboration with the National Institute of Mental Health in the US, a large international trial involving his computer program is now being carried out at more than 20 sites across five continents.

The more options that exist for patients, the better that clinicians can tailor treatment for their patient’s individual needs, Prof. Bar-Haim observes. There are always patients for whom medication or cognitive therapy is not a viable option, he explains. “Psychological disorders are complex, and not every patient will respond well to every treatment. It’s great to have new methods that have a basis in neuroscience and clinical evidence.”

Source: Science Daily

ScienceDaily (June 11, 2012) — Non-medical prescription drug use by college students is a growing trend on most campuses, according to the U.S. Department of Education’s Higher Education Center for Alcohol, Drug Abuse and Violence Prevention. Due to this trend, Western Illinois University Department of Health Sciences Assistant Professor Amanda Divin and her colleague, Keith Zullig, an associate professor in the West Virginia University School of Public Health, recently conducted and published a study that explores non-medical prescription drug use and depressive symptoms in college students.

Divin and Zullig utilized data from the fall 2008 American College Health Association National College Health Assessment (ACHA-NCHA), a national research survey that addresses seven areas of health and behavior of college students, one of which is alcohol, tobacco and other drug use. The sample used for the study (from the ACHA-NCHA data) contained 26,600 randomly selected college students from 40 campuses in the U.S. The student respondents were asked about their non-medical prescription drug use (including painkillers, stimulants, sedatives and antidepressants) and mental health symptoms within the last year.

According to Divin’s and Zullig’s results, approximately 13 percent of the college-student respondents reported non-medical prescription drug use, with those who reported feeling hopeless, sad, depressed or considered suicide being significantly more likely to report non-medical use of any prescription drug. The results also showed this relationship was more pronounced for females who reported painkiller use. The study — which is titled, “The association between non-medical prescription drug use, depressive symptoms, and suicidality among college students” — will appear in the August 2012 issue of Addictive Behaviors: An International Journal.

"Because prescription drugs are tested by the U.S. Food and Drug Administration and prescribed by a doctor, most people perceive them as ‘safe’ and don’t see the harm in sharing with friends or family if they have a few extra pills left over," Divin explained. "Unfortunately, all drugs potentially have dangerous side effects. As our study demonstrates, use of prescription drugs — particularly painkillers like Vicodin and Oxycontin — is related to depressive symptoms and suicidal thoughts and behaviors in college students. This is why use of such drugs need to be monitored by a doctor and why mental health outreach on college campuses is particularly important."

Divin and Zullig believe the results suggest that students are self-medicating their psychological distress with prescription medications.

"Considering how common prescription sharing is on college campuses and the prevalence of mental health issues during the college years, more investigation in this area is definitely warranted," Divin added. "Our study is just one of the many first steps in exploring the relationship between non-medical prescription drug use and mental health."

Source: Science Daily

ScienceDaily (June 11, 2012) — Sportsmen and women have been known to dope with the blood hormone Epo to enhance their performance. Researchers from the University of Zurich have now discovered, through animal testing, that Epo has a performance-enhancing effect in the brain shortly after an injection by improving oxygen transport in blood. As Epo also increases motivation, it could be useful in treating depression, experts say.

The well-known blood hormone Epo is not only used for medicinal purposes; some athletes misuse it for doping. It boosts the number of red blood cells, thereby increasing the transport of oxygen to the muscles. This leads to improvements in performance, which can especially give endurance athletes such as cyclists or marathon runners the edge.

Epo has immediate impact on exercise performance

In a recently published study, Max Gassmann, a veterinary physiologist from the University of Zurich, proved that Epo also drastically increases motivation in the brain as soon as it has been injected, without the number of red blood cells increasing.

Gassmann’s team tested exercise performance of differently treated mice, studying genetically modified mice that produce human Epo solely in the brain and mice that the researchers had injected with Epo and the hormone reached the brain thus by blood. Both mouse groups exhibited an increased performance on the treadmill compared to the untreated control animals. “We assume that Epo in the brain triggers a motivation boost to increase physical performance,” explains Professor Gassmann. He and his team are now testing the performance-enhancing effect of Epo on volunteers.

Epo probably has an impact on people’s moods, too. It might thus be used in patients who suffer from depression. The latest experiments conducted by a German-Danish research group reveal that Epo can also alleviate the condition of patients suffering from schizophrenia by improving their mental performance.

Source: Science Daily

June 11, 2012

The younger a woman is when she goes through the menopause, the greater may be her risk of having a brain (cerebral) aneurysm, suggests research published online first in the Journal of NeuroInterventional Surgery.

A cerebral aneurysm refers to an abnormal bulging of one of the arteries in the brain, which is often only discovered when it ruptures, causing a potentially fatal and/or disabling bleed.

Women are more prone to cerebral aneurysms than men. And fluctuations in the female hormone oestrogen have been implicated in the development of aneurysms, the incidence of which, along with cardiovascular disease, rises sharply after menopause.

The authors base their findings on 76 postmenopausal women who had had a cerebral aneurysm, which, in most cases had not ruptured, and who were subsequently quizzed about their medical and reproductive histories.

Conditions, such as high blood pressure, diabetes, high cholesterol and an underactive thyroid gland (hypothyroidism) can all boost the risk of a stroke, while the number of pregnancies and the age at which periods start and stop determine lifetime exposure to oestrogen.

This information was then compared with that taken from more than 4,500 women participants of the 2002 National Institute of Child Health and Human Development Contraceptive and Reproductive Experiences Study, and matched for age and educational attainment.

The average age at which women in both groups had started the menopause was similar, and analysis of the results showed that later menopause and use of hormone replacement therapy (HRT) protected against the risk of a cerebral aneurysm, lessening the risk by 21% and 77%, respectively.

Premature menopause - before the age of 40 - had occurred in one in four (26%) of the women who had had an aneurysm compared with around one in five (19%) of those in the comparison group.

And each successive four year increase in the age at which a woman went through the menopause lessened the likelihood of a cerebral aneurysm by around 21%.

Smoking did not seem to be linked to an increase in risk, while alcohol consumption was of borderline significance.

The outcomes for ruptured cerebral aneurysms are poor, with around one in two people who have one likely to die. One in 10 people die before they reach hospital and of those who survive, one in five is severely disabled, say the authors, so finding a potential marker may help to detect the condition earlier.

"Loss of oestrogen earlier in a woman’s life may contribute to the [development] of cerebral aneurysm," conclude the authors, adding that HRT may protect against this. And they suggest: "These data may identify a risk factor for [the development of this condition] and also a potential target for future therapies."

Provided by British Medical Journal

Source: medicalxpress.com

June 11, 2012

The American Academy of Neurology has issued an updated guideline outlining the best treatments for infantile spasms, a rare type of seizure that can occur in infants and young children. The guideline, which was co-developed with the Child Neurology Society, is published in the June 12, 2012, print issue of Neurology, the medical journal of the American Academy of Neurology.

Infantile spasms is a rare disorder that usually begins in infants aged four to six months. The spasms are a type of seizure that mainly consists of a sudden bending forward of the body with stiffening of the arms and legs or arching of the back while the arms and legs are extended. Infantile spasms rarely respond to the usual anti-seizure medications. Most children with infantile spasms have developmental disabilities later in life.

The guideline found that the hormone therapy adrenocorticotropic hormone, also known as ACTH, may be effective for treatment of infantile spasms. The seizure drug vigabatrin may also be considered for treatment, although evidence suggests ACTH may be more effective than vigabatrin. For children with seizures caused by the genetic disorder tuberous sclerosis complex, however, vigabatrin may be more effective.

The guideline, which is based on a review of all available evidence on treatment for infantile spasms and is an update of a guideline published in 2004, also found that low-dose ACTH is probably as effective as high-dose ACTH and it may lower the risk of side effects.

There is not enough evidence to know whether other treatments, alone or combined, are effective in treating infantile spasms, according to the guideline.

The guideline recommends that early diagnosis and early treatment may lead to better long-term outcomes for children’s development and learning skills.

"It is important for parents to talk to their child’s doctor if they suspect their child may be having seizures or spasms because early diagnosis and treatment may help in the long term with educational and learning skills," said guideline author Cristina Go, MD, of the Hospital for Sick Children in Toronto.

Go noted that children with the syndrome also have a specific pattern that shows up in tests of brain waves, and an EEG (electroencephalogram) is required for confirmation of the diagnosis.

Provided by American Academy of Neurology

Source: medicalxpress.com

June 10, 2012

The sight of unhealthy food during a period of sleep restriction activated reward centers in the brain that were less active when participants had adequate sleep, according to a new study using brain scans to better understand the link between sleep restriction and obesity.

Researchers from St. Luke’s – Roosevelt Hospital Center and Columbia University in New York performed functional magnetic resonance imaging (fMRI) on 25 men and women of normal weights while they looked at images of healthy and unhealthy foods. The scans were taken after five nights in which sleep was either restricted to four hours or allowed to continue up to nine hours. Results were compared.

"The same brain regions activated when unhealthy foods were presented were not involved when we presented healthy foods," said Marie-Pierre St-Onge, PhD, the study’s principal investigator. "The unhealthy food response was a neuronal pattern specific to restricted sleep. This may suggest greater propensity to succumb to unhealthy foods when one is sleep restricted."

Previous research has shown that restricted sleep leads to increased food consumption in healthy people, and that a self-reported desire for sweet and salty food increases after a period of sleep deprivation. St-Onge said the new study’s results provide additional support for a role of short sleep in appetite-modulation and obesity.

"The results suggest that, under restricted sleep, individuals will find unhealthy foods highly salient and rewarding, which may lead to greater consumption of those foods," St-Onge said. "Indeed, food intake data from this same study showed that participants ate more overall and consumed more fat after a period of sleep restriction compared to regular sleep. The brain imaging data provided the neurocognitive basis for those results.”

Provided by American Academy of Sleep Medicine

Source: medicalxpress.com

June 10, 2012

MRI scans from a study being presented today at SLEEP 2012 reveal how sleep deprivation impairs the higher-order regions in the human brain where food choices are made, possibly helping explain the link between sleep loss and obesity that previous research has uncovered.

Twenty-three healthy adults participated in two sessions using functional magnetic resonance imaging (fMRI), one after a normal night’s sleep and a second after a night of sleep deprivation. In both sessions, participants rated how much they wanted various food items shown to them while they were inside the scanner.

"Our goal was to see if specific regions of the brain associated with food processing were disrupted by sleep deprivation," said lead author Stephanie Greer, a graduate student at the Sleep and Neuroimaging Laboratory at the University of California, Berkeley.

Results show that sleep deprivation significantly impaired brain activity in the frontal lobe, a region critical for controlling behavior and making complex choices, such as the selection of food to eat. The study suggests that sleep loss may prevent the higher brain functions normally critical for making appropriate food choices, rather than necessarily changing activity in deeper brain structures that react to basic desire.

"We did not find significant differences following sleep deprivation in brain areas traditionally associated with basic reward reactivity,” Greer said. “Instead, it seems to be about the regions higher up in the brain, specifically within the frontal lobe, failing to integrate all the different signals that help us normally make wise choices about what we should eat.”

She added that this failure of the frontal lobe to optimally gather the information needed to decide on the right types of foods to eat – such as how healthy relative to how tasty an item may be – may represent one brain mechanism explaining the link between sleep loss and obesity.

"These results shed light on how the brain becomes impaired by sleep deprivation, leading to improper food choices," Greer said.

Provided by American Academy of Sleep Medicine

Source: medicalxpress.com