Amyloid Deposits in Cognitively Normal People May Predict Risk for Alzheimer’s Disease

For people free of dementia, abnormal deposits of a protein associated with Alzheimer’s disease are associated with increased risk of developing the symptoms of the progressive brain disorder, according to two studies from researchers at Washington University in St. Louis. The studies, primarily funded by the National Institute on Aging (NIA), part of the National Institutes of Health, linked higher amounts of the protein deposits in dementia-free people with greater risk for developing the disease, and with loss of brain volume and subtle declines in cognitive abilities.

Normal brain vs. Alzheimers brain

National Survey Tracks Rates of Common Mental Disorders Among American Youth

Only about half of American children and teenagers who have certain mental disorders receive professional services, according to a nationally representative survey funded in part by the National Institute of Mental Health (NIMH). The survey also provides a comprehensive look at the prevalence of common mental disorders.

The results are part of the National Health and Nutrition Examination Survey (NHANES), a collaboration between NIMH and the National Center for Health Statistics of the Centers for Disease Control and Prevention. The survey conducted from 2001 to 2004 had 3,042 participants. These most recent results include data from children and adolescents ages 8 to 15, and were published online ahead of print December 14, 2009, in the journal Pediatrics [1].

Neurodegenerative Disease and the Coming Epidemic

At Neuroscience 2008, the 38th annual meeting of the Society for Neuroscience held last month in Washington D.C., a number of researchers presented evidence that a small, soluble, clustered form of a protein called amyloid beta may be responsible for brain damage in Alzheimer’s disease patients [1]. In addition, scientists report that they are finding new sources and uses of neural stem cells that may replace cells damaged by neurodegenerative disorders such as Alzheimer’s and Parkinson’s disease [2].

neuronal-network.jpg
Creative Commons License photo credit: neurollero

Why are these reports significant? Because until recently, large insoluble amyloid beta plaques, or deposits, were considered the likely cause of Alzheimer’s disease. The plaques were thought to disrupt brain cell communication. However, new findings show that an early (i.e. small), soluble, clustered form of amyloid beta called protofibrils is found in high levels in the brains of people with Alzheimer’s disease [1]. Researchers also found a strong correlation between the presence of high levels of protofibrils in the brains of transgenic mouse models of Alzheimer’s disease and the cognitive impairments associated with the disease.

Encephalon #58 – Decision Making

Welcome to the 58th edition of Encephalon, where we highlight some of the best neuroscience and psychology blog posts from around the blogosphere. This edition includes 20 articles on a variety of interesting topics, including intelligence, belief, neurodegeneration, multi-tasking, memory, grief and consciousness.

There’s a revolution occurring on the Web: those “authoritative” articles written on traditional, static websites are being replaced with blogs, wikis and online social networks. In the sphere of health, medicine and information technology, this “real-time Web” consists of many who are professionals in the field; their posts are listed below.
In the digital age, these are the characteristics of new media: recent, relevant, reachable and reliable.

This edition of Encephalon coincides with the historic 44th U.S. Presidential election. As with every election, voters had to decide which candidate for whom to cast their ballot. Although a recent brain-imaging study found that voting decisions are more associated with the brain’s response to negative aspects of a politician’s appearance than to positive ones [1], many other sources of information come into play when we make important and complex decisions. Indeed, studies have shown that decision making is largely an unconscious process [2], in which a set of attributes, including needs, preferences, values and emotions, shape our response to sensory input.

Will there be engaging and thought-provoking articles below? Will each of us learn something new as we read through the posts? Will this edition of Encephalon be successful?

Let’s move through each of the attributes and shape our response to these questions.

The Cancer Genome Atlas Reports Molecular Characterization of Brain Tumors

A large-scale, multi-dimensional analysis of the genomic characteristics of glioblastoma, the most common primary brain tumor in adults, provides new insights into the roles of several genes and defines core biological pathways altered in tumor development [1]. The new Cancer Genome Atlas study, published in the September 4th advanced online edition of the journal Nature, also reveals a link between the DNA repair enzyme MGMT and a hypermutation phenotype, and has potential implications for the diagnosis and treatment of glioblastoma.

Glioblastoma is the most common and aggressive type of brain cancer. Patients newly diagnosed with glioblastoma have a median survival of approximately one year with generally poor response to therapy [2]. Gene expression profiling studies suggest multiple subtypes of glioblastoma that, when fully defined, may allow for more personalized therapeutic approaches [3-4].