Among the many unpleasant side effects of chemotherapy treatment, researchers have just confirmed another: chemo brain. The term refers to the mental fog that chemotherapy patients report feeling during and after treatment. According to Jame Abraham, a professor at West Virginia University, about a quarter of patients undergoing chemotherapy have trouble focusing, processing numbers, and using short-term memory.
Our cognitive abilities tend to decline when we get older, as we have trouble remembering old facts and skills and learning new ones. But a little young blood reverses some ill effects of old age, at least in mice, researchers reported at the Society for Neuroscience conference last week.
Neuroscientist Saul Villeda and his team gave elderly mice infusions of blood from younger, sprightlier members of their species. The old mice fortified with young blood improved on learning and memory tasks, such as finding a platform submerged in water and getting conditioned (think Pavlov’s dogs) to fear situations associated with electric shocks.
Quick: commit this to memory. There will be a quiz.
Neuroscientists implanted artificial memories into slices of rat brain, they reported in Nature Neuroscience online. By jolting the rodent brain cells with electrical current, the researchers produced memory-like patterns of neuron activity that survived for around 10 seconds. This is the first time that researchers have created memory without a brain.
Human astrocyte. The vivid color is from GFP, not drugs.
The real news is the importance of a type of brain cells called astroglia, which have long been ignored while researchers focus on neurons. THC, the psychoactive chemical in marijuana, impairs working memory by connecting to astroglia, according to a new paper published in Cell. So the star-shaped astroglia turn out to be the real star of this study.
What’s the News: When prions or amyloids make the news, it’s usually because they cause mad cow disease or Alzheimer’s—prions, after all, cause any proteins they touch to become as misfolded as they are, and amyloids, which are large clumps of wadded-together proteins, can jam the workings of cells.
But a new study in Cell suggests that a prion-like protein that forms amyloids has a normal, vital function in the brain. Far from being a memory destroyer, this protein, called CPEB, is necessary for long-term memory in fruit flies.
New research suggests the mere act of walking through a doorway helps people forget, which could explain many millions of confusing moments that happen each day around the world. A study published recently in The Quarterly Journal of Experimental Psychology found that participants who walked through doorways in a virtual reality environment were significantly more likely to forget memories formed in another room, compared with those who traveled the same distance but crossed no thresholds.
A 68-year-old concert cellist suffering from severe amnesia can still learn new music, researchers reported [pdf] at the Society for Neuroscience conference this weekend. In 2005, the cellist suffered a bout of herpes encephalitis, a dangerous infection that causes inflammation in the brain. His medial temporal lobes, brain structures important in remembering facts and events—what scientists call explicit memory—were destroyed. As a result, the cellist, referred to by the initials PM, was left with both retrograde amnesia (meaning he couldn’t remember events from his past) and anterograde amnesia (meaning he couldn’t form new memories).
What’s the News: One of memory’s big jobs is to keep straight what actually happened versus what we imagined: whether we said something out loud or to ourselves, whether we locked the door behind us or just thought about locking the door. That ability, a new study found, is linked to the presence of a small fold in the front of the brain, which some people have and others don’t—a finding that could help researchers better understand not only healthy memory, but disorders like schizophrenia in which the line between the real and the imagined is blurred.
Scans of a brain with a distinctive paracingulate sulcus (left, marked by arrow) and without one (right)
A twice-daily dose of insulin, sprayed deep in the nose for easy transit to the brain, may slow or stop the progression of Alzheimer’s disease, according to a new pilot study. The researchers gave 104 patients with mild to moderate Alzheimer’s disease or pre-Alzheimer’s cognitive impairment one of three nasal sprays for four months. One group of patients got a nasal spray with a moderate dose of insulin twice a day, one group got a higher dose, and the third got a squirt of saline solution, as a placebo. The memory, cognitive abilities, and day-to-day functioning of patients given insulin stayed constant or improved slightly—particularly for those given the moderate dose of insulin rather than the high dose—while the abilities and memory of patients given the placebo declined.
What’s the News: Most of us need everyone to stop talking when we perform mental math. But for children trained to do math visually with a “mental abacus,” verbal disturbances roll off their backs, prompting psychologists to posit that unlike the rest of us, they aren’t routing their calculations through words.