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].

Mapping Connections in the Human Brain

The first high-resolution structural connection map of the human cerebral cortex was published earlier this month in the journal PLoS Biology. The study reveals regions that are highly connected and central, forming a structural core network [1]. Intriguingly, this core network consists of many areas that are more active when we’re at rest than when we’re engaged in a task that requires concentration.

Nirvana in the Right Hemisphere: A Stroke of Insight

In January 2007, a meta-analysis published in the journal Neurology determined updated rates of the most common neurological disorders [1]. The review found that 183 out of every 100,000 people suffer a stroke each year. Most studies included in the analysis attributed 80% or more of all strokes to ischemia (meaning a localized deficiency of blood caused by a clot obstructing arterial flow). In contrast, the incidence of a hemorrhagic stroke (meaning bleeding in the brain) is much more rare and is associated with higher mortality rates. Indeed, a study of stroke incidence rates and case fatality in 15,792 middle-aged adults found that hemorrhagic strokes were 4.5 times as fatal as ischemic strokes [2].