The basic “scaffolding” for the vertebrate brain has been found in an unexpected distant relative: a marine worm, a new study reports. The worm’s brain is much simpler than that of even the simplest vertebrates – but it contains three signaling centers almost identical to those found in the brains of vertebrate embryos. I leaped up and did a happy dance when I read this news, because it’s a clue to one of the greatest mysteries in neuroscience today. See, for most of science history, evolutionary biologists have found the vertebrate brain to be pretty enigmatic. The closest relatives of … Continue reading The Worm Did It!
Just a minute of physical exertion can seriously impair a person’s memory of the threat that triggered it, says a new study. When we undergo a strenuous task, such as a chase or a fight, immediately after witnessing an event, we have much less ability to remember the event’s details than if we’d taken time to process what we’ve seen. This calls the concept of eyewitness testimony into serious question. As I’ve written here and Jonah Lehrer has written here, our memories aren’t nearly as static as we might like to think. In fact, each time we recall a memory, … Continue reading Mixed-Up Memories
Yes, it’s that special time of year again – time for flamboyant bouquets and chalky candy to appear at office desks – time for Facebook pages to drown in cloying iconography – time for self-labeled “forever aloners” to dredge the back alleys of OKCupid in last-ditch desperation – and time for me to load up my trusty gatling crossbow with oxytocin-tipped darts and hit the streets. Oh, and it’s time for everyone to complain about how misogynistic all this “Game” stuff is. So, while I guess I could write about, say, a new study that says cutting your romantic partner some slack can make him or … Continue reading Why I Love and Hate “Game”
Those of us who have loads of Facebook friends tend to have greater development in several specific brain regions, says a new study. Researchers have found a strong correlation between large numbers of Facebook connections and increased development of gray matter – tissue containing neuron cell bodies, where dense communication occurs – in several regions crucial for social interaction: the amygdala, the right superior temporal sulcus (STS), the left middle temporal gyrus (MTG), and the right entorhinal cortex (EC). Intriguingly, the size of some of these regions seems to correlate only with the size of people’s online social networks – not their real-world ones. It’s not clear … Continue reading Digital Friendships
Our big brains may be the result of a doubled gene that lets brain cells migrate to new areas, says a new study. The gene, known as SRGAP2, has been duplicated in our genomes at least twice in the four million years since our ancestors diverged from those of the other great apes. It codes for a certain protein that interferes with filopodia – tiny molecular structures that shape the growth of neurons in a developing brain. Researchers think that as SRGAP’s protein disrupted the “normal” growth of our ancestors’ filopodia, millions of their neurons migrated outward to thicken the cerebral cortex – … Continue reading Doubling Up
The origins of subjective consciousness probably lie in an introspective brain network common to most mammals, says a new study. When we “zone out” and let our minds wander, a functional (as opposed to structural) brain network known as the default mode network (DMN) becomes active. The DMN links our frontal lobe – an area associated with planning and abstract thought – with areas of the temporal and parietal lobes that help us associate memories with ideas and emotions. In short, this network allows us to become “lost” in thought, rather than occupied with our environment, or with a specific goal. Since goal-directed … Continue reading The Roots of Consciousness
Yawning may be a reflex for cooling our brains off, a new study suggests. People are less likely to yawn when their own body temperature is lower than that of the surrounding environment, the research shows – in fact, a person’s tendency to yawn actually varies with theseasons, becoming more frequent in winter and less frequent in summer. Scientists have debated the cause(s) of yawning for centuries. Some have explained it as a sort of reflexive muscle stretch, because it often occurs along with other stretching behavior. Others have suggested that yawns may help increase alertness, and that contagious yawning might help signal members of a social group to become more alert. The theory that yawning helps regulate brain temperature dates back at least to 2007 – but … Continue reading Cooler Heads