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Does evolution explain why the human brain supports religious belief? Dimitrios Kapogiannis and Jordan Grafman, scientists at the National Institutes of Health, follow up on a recent scientific paper by stating that brain networks that evolved for other purposes have given rise to our capacity for religious belief and experience. Andrew Newberg, the radiologist and psychiatrist who wrote How God Changes Your Brain, takes a different approach. He argues that the brain may be an instrument of religious experience but is not necessarily the origin of that experience. Each side of the debate first wrote a position statement; the sides then exchanged statements and wrote rejoinders.

The scientists, including several at MIT, are working on technologies needed to accelerate the slow and laborious process that the C. elegans researchers originally applied to worms. With these technologies, they intend to map the connectomes of our animal cousins, and eventually perhaps even those of humans. Their results could fundamentally alter our understanding of the brain. Mapping the millions of miles of neuronal “wires” in the brain could help researchers understand how those neurons give rise to intelligence, personality and memory, says Sebastian Seung, professor of computational neuroscience at MIT. For the past three years, Seung and his students have been building tools that they hope will allow researchers to unravel some of those connections. To find connectomes, researchers will need to employ vast computing power to process images of the brain. But first, they need to teach the computers what to look for.

“Instead of specifying the details of how the computer does something, you give it an example of what you want it to do and an algorithm that tries to figure out how to do what you want,” says Jain. After the computer is trained on the human tracings, it is applied to electron micrographs that have not been traced by humans. This new technique represents the first time that computers have been effectively taught to segment any kind of images, not just neurons.

“Doing such a microscopic level of resolution seemed to be infeasible at the time,” he says. “But now I’m coming around to the idea that something like that may well be possible.” The machine learning technology that Seung and his students are developing could be “a big leap forward” in making that kind of diagram a reality, Sporns adds.

‘Grid cells’ that act like a spatial map in the brain have been identified for the first time in humans, according to new research by UCL scientists which may help to explain how we create internal maps of new environments. The study is by a team from the UCL Institute of Cognitive Neuroscience and was funded by the Medical Research Council and the European Union. Published today in Nature, it uses brain imaging and virtual reality techniques to try to identify grid cells in the human brain. These specialised neurons are thought to be involved in spatial memory and have previously been identified in rodent brains, but evidence of them in humans has not been documented until now.

emotional data funnels to the brain, exciting the left anterior temporal region in particular, then smolders to the surface of the face, where two muscles, standing at attention, are roused into action: The zygomatic major, which resides in the cheek, tugs the lips upward, and the orbicularis oculi, which encircles the eye socket, squeezes the outside corners into the shape of a crow’s foot. The entire event is short — typically lasting from two-thirds of a second to four seconds — and those who witness it often respond by mirroring the action, and smiling back.

For decades, many psychologists agreed that smiles reflected a vast array of emotions rather than a universal expression of happi­ness. This belief persisted until the 1970s, when Paul Ekman and Wallace Friesen, psychologists at the University of California at San Francisco, captured the precise muscular coordinates behind 3,000 facial expressions in their Facial Action Coding System, known as FACS. Ekman and Friesen used their system to resurrect Duchenne’s distinction, by that time forgotten, between genuine smiles of enjoyment and other types of smiles.

Some researchers now believe that genuine smiles are not transient sparks of emotion but rather clear windows into a person’s core disposition.

The cortex of the human brain holds more than 100 trillion neural connections, or synapses, packed into a layer of tissue just 2 to 4 millimeters thick. Visualizing these densely packed units individually has proved extremely challenging. Synapses in the brain are crowded in so close together that they cannot be reliably resolved by even the best of traditional light microscopes, explains Stanford neuroscientist Stephen Smith in a press release from the university.

A connectome is a comprehensive map of neural connections in the brain. The production and study of connectomes, known as connectomics, may range in scale from a detailed map of the full set of neurons and synapses within part or all of the nervous system of an organism to a macro scale description of the functional and structural connectivity between all cortical areas and subcortical structures. The term "connectome" is used primarily in scientific efforts to capture, map, and understand the organization of neural interactions within the brain.

It is clear that, like the genome, which is much more than just a juxtaposition of genes, the set of all neuronal connections in the brain is much more than the sum of their individual components. The genome is an entity it-self, as it is from the subtle gene interaction that [life] emerges. In a similar manner, one could consider the brain connectome, set of all neuronal connections, as one single entity, thus emphasizing the fact that the huge brain neuronal communication capacity and computational power critically relies on this subtle and incredibly complex connectivity architecture.

New research conducted at The Scripps Research Institute shows that this road atlas undergoes constant revisions as the brain of a young animal develops, with new routes forming and others dropping away in a matter of hours. "We have shown that the connectome is dynamic during development, but we expect it will also change according to an individual's experience and in response to disease,"

Cline's group has been studying how experience—the different sights and sounds and other environmental cues picked up by neurons—change connections and activities in the brain through a process known as plasticity. "Based on our prior research we expected that the connectome would be dynamic," says Cline. To start to document how the connectome changes and test current models of how the map is laid out, Cline and colleagues turned to the frog Xenopus laevis. They combined two new techniques to map in great detail all the connections that form during tadpole development in an area of the brain that receives and interprets signals from the eyes. In the nervous system, information is handed from one nerve cell to another through two arms, called dendrites and axons, stretching out from opposite sides of each cell. The axon carries information away from a nerve cell, or neuron, and passes it to the dendrite of another; dendrites receive the information, which travels through the cell to the axon. The region where information is transferred from one neuron to another (and where axons and dendrites connect) is called the synapse.

Cline's study shows instead the process is not as selective. Each growing dendrite samples not one but many possible partners before selecting one with which to maintain contact. As new branches grow from dendrites, they form many immature synapses on axons. Then, as each new dendrite branch matures, most immature synapses are eliminated; the ones not eliminated mature into stable synapses. "We did not know that dendrites make so many connections that are then removed," says Cline. "It is always fun in science when you see that what was expected is not what actually happens."

The human brain works incredibly fast but visual impressions are so complex that their processing takes up to several hundred milliseconds before they enter our consciousness.  Researchers say they know why this delay may vary in length; if you already know what you are about to see, you recognize it faster.

In an experiment, participants perceived stimuli more efficiently and faster if they knew what to expect. To investigate this, the scientists showed the participants images with a background of randomly distributed dots on a monitor. During an image sequence, the distribution of the dots systematically changed such that a symbol gradually appeared. Following each image, the participants indicated if they could see the symbol by pressing a button. As soon as the symbol had appeared fully and was clearly recognizable, the scientists presented the same image sequence in reverse order, such that the symbol gradually faded again.

“Expectations based on previously acquired information apparently help to perceive the object consciously”

"Generally, positive mood has been found to enhance creative problem solving and flexible yet careful thinking," says Ruby Nadler, a graduate student at the University of Western Ontario.