Researchers have identified a novel mechanism that helps explain the power of placebos and nocebos.

Described in the Sept. 10 on-line issue of the Proceedings of the National Academy of Sciences (PNAS), the new findings demonstrate that the placebo effect can be activated outside of conscious awareness, and provide an explanation for how patients can show clinical improvement even when they receive treatments devoid of active ingredients or of known therapeutic efficacy.

"In this study, we used a novel experimental design and found that placebo and nocebo [negative placebo] effects rely on brain mechanisms that are not dependent on cognitive awareness," explains first author Karin Jensen, PhD, of the Department of Psychiatry and the Martinos Center for Biomedical Imaging at Massachusetts General Hospital (MGH) and the Program in Placebo Studies (PiPS) at Beth Israel Deaconess Medical Center/Harvard Medical School. "A person can have a placebo or nocebo response even if he or she is unaware of any suggestion of improvement or anticipation of getting worse."

“Generating interesting connections between disparate subjects is what makes art so fascinating to create and to view … we are forced to contemplate a new, higher pattern that binds lower ones together.”

It seems to be the season for fascinating meditations on consciousness, exploring such questions as what happens while we sleep, how complex cognition evolved, and why the world exists. Joining them and prior explorations of what it means to be human is The Ravenous Brain: How the New Science of Consciousness Explains Our Insatiable Search for Meaning (public library) by Cambridge neuroscientist Daniel Bor in which, among other things, he sheds light on how our species’ penchant for pattern-recognition is essential to consciousness and our entire experience of life.

The process of combining more primitive pieces of information to create something more meaningful is a crucial aspect both of learning and of consciousness and is one of the defining features of human experience. Once we have reached adulthood, we have decades of intensive learning behind us, where the discovery of thousands of useful combinations of features, as well as combinations of combinations and so on, has collectively generated an amazingly rich, hierarchical model of the world. Inside us is also written a multitude of mini strategies about how to direct our attention in order to maximize further learning. We can allow our attention to roam anywhere around us and glean interesting new clues about any facet of our local environment, to compare and potentially add to our extensive internal model.

Scientists have claimed to have solved the mystery of why coffee never tastes as good as it smells.

Apparently, the act of swallowing the drink sends a burst of aroma up the back of the nose from inside the mouth, activating a “second sense of smell” in the brain that is less receptive to the flavour, causing a completely different and less satisfying sensation.

“We have got two senses of smell. One sense is when you inhale things from the environment into you, and the other is when the air comes out of you up the nasal passage and is breathed out through the nose,” the Telegraph quoted Prof Barry Smith, of the University of London, as saying at the British Science Festival in Aberdeen.

The phenomenon is down to the fact that, although we have sensors on our tongue, 80 percent of what we think of as taste actually reaches us through smell receptors in our nose, the paper said. The receptors, which relay messages to our brain, react to odours differently depending on which direction they are moving in, it added.

In the case of coffee, the taste is also hampered by the fact that 300 of the 631 chemicals that combine to form its complex aroma are wiped out by saliva, causing the flavour to change before we swallow it, Prof Smith added.

Supplementation with the omega-3 fatty acid DHA may help improve reading skills and behavior in kids who need help most — those whose test scores place them in the bottom 20% of their elementary school class — according to a new controlled trial.

Researchers at Oxford University’s Center for Evidence-Based Intervention studied 362 7- to 9-year-old children who had placed in the bottom third of their class in reading scores. For 16 weeks, the children were given either a placebo or 600 mg of DHA (docosahexaenoic acid). The DHA was extracted from algae, which are the original source of the omega-3 fatty acids found in fish.

Over the 16-week trial, the children receiving placebos progressed in their reading skills as expected. But those students who received DHA and had scored in the bottom 20% of readers at the start of the study advanced by nearly an extra month, while those in the bottom 10% gained nearly two extra months of progress. Students whose reading skills were less impaired — those whose scores had placed them at the highest end of the bottom third — did not see extra improvements with DHA.

Parents of the kids who received DHA also rated their children as more attentive and less restless, as compared with those who got placebo. However, teachers did not report improvement in the children’s behavior.

Study finds new benefit of coffee: It reduces pain

The surprising finding is based on a study involving 48 volunteers who agreed to spend 90 minutes performing fake computer tasks meant to mimic office work. The tasks were known to cause pain in the shoulders, neck, forearms and wrists, and the researchers wanted to compare how people with chronic pain and those who were pain-free tolerated the tasks.

As a matter of convenience, the scientists allowed people to drink coffee before taking the test “to avoid unpleasant effects of caffeine deprivation, e.g. decreased vigor and alertness, sleepiness, and fatigue,” they reported.

But when it came time to analyze the data, the researchers from Norway’s National Institute of Occupational Health and Oslo University Hospital noticed that the 19 people who drank coffee reported a lower intensity of pain than the 29 people who didn’t.

In the shoulders and neck, for instance, the average pain intensity was rated 41 (on a 100-point scale) among the coffee drinkers and 55 for the coffee abstainers. Similar gaps were found for all pain sites measured, and coffee’s apparent pain-mitigation effect held up regardless of whether the subjects had chronic pain or not.

The authors of the study, which was published this week in the journal BMC Research Notes, cautioned that since the study wasn’t designed to test coffee’s influence on pain, the results come with many uncertainties. For starters, the researchers don’t know how much coffee the coffee drinkers consumed before taking the computer tests. They also doubt that the coffee drinkers and abstainers were similar in all respects except for their java consumption. Problems like these tend to undermine the importance of the findings. But those reservations are unlikely to trouble the legions of coffee drinkers looking for any reason not to cut back on their daily caffeine habit.

Have you ever noticed how tiresome it can be to follow a conversation at a noisy party? Rest assured: this is not necessarily due to bad hearing – although that might make things worse. Scientists at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig have found that adverse listening situations are difficult for the brain, partly because they draw on the same, limited resources supporting our short-term memory. The new findings are particularly relevant to understanding the cognitive consequences of hearing damage, a condition that affects an increasing number of people.

Brain Networks of Explicit and Implicit Learning

Are explicit versus implicit learning mechanisms reflected in the brain as distinct neural structures, as previous research indicates, or are they distinguished by brain networks that involve overlapping systems with differential connectivity? In this functional MRI study we examined the neural correlates of explicit and implicit learning of artificial grammar sequences. Using effective connectivity analyses we found that brain networks of different connectivity underlie the two types of learning: while both processes involve activation in a set of cortical and subcortical structures, explicit learners engage a network that uses the insula as a key mediator whereas implicit learners evoke a direct frontal-striatal network. Individual differences in working memory also differentially impact the two types of sequence learning.

Children get their sense of humour from their parents as a study has found babies as young as six months learn to laugh at the same thing as their mothers and fathers.