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Five years ago, researchers set out to replicate experiments from 50 high-impact cancer biology papers. Now, due to various challenges relating to a lack of funding and expertise, the project only expects to complete just 18 studies. Science Magazine reports: The Reproducibility Project: Cancer Biology (RP:CP) began in October 2013 as an open effort to test replicability after two drug companies reported they had trouble reproducing many cancer studies. The work was a collaboration with Science Exchange, a company based in Palo Alto, California, that found contract labs to reproduce a few key experiments from each paper. Funding included a $1.3 million grant from the Laura and John Arnold Foundation, enough for about $25,000 per study. Experiments were expected to take 1 year.

Costs rose and delays ensued as organizers realized they needed more information and materials from the original authors; a decision to have the proposed replications peer reviewed also added time. Organizers whittled the list of papers to 37 in late 2015, then to 29 by January 2017. In the past few months, they decided to discontinue 38% or 11 of the ongoing replications, Errington says. (Elizabeth Iorns, president of Science Exchange, says total costs for the 18 completed studies averaged about $60,000, including two high-priced "outliers.") One reason for cutting off some replications was that it was taking too long to troubleshoot or optimize experiments to get meaningful results... So far, the project has published replication results for 10 of the 18 studies. "Five were mostly repeatable, three were inconclusive, and two studies were negative, but the original findings have been confirmed by other labs," reports Science Magazine. "In fact, many of the initial 50 papers have been confirmed by other groups, as some of the RP:CB's critics have pointed out."

An anonymous reader shares a report: Naked mole rats are adorably ugly creatures that challenge what we think we know about aging. Naked mole rats can live to be 30 years old. Further, female mole rats show no signs of menopause, and remain highly fertile even into their final years of life. Neurogenesis in naked mole rats continues over two decades, and their hearts and bones don't seem to change significantly over time. They rarely get cancer. Hell, they can even live up to 18 minutes utterly deprived of oxygen.

[...] At Google's biotech company, Calico, in San Francisco, California, biologist Rochelle Buffenstein is looking to the naked survivors to unlock their secrets of aging. Buffenstein says naked mole rats violate to the Gompertz-Makeham law, and she has over 3,000 data points to back her conclusion. After reaching adulthood six months into their lives, a naked mole rat's mortality risk remained the same for the rest of its days her analysis revealed. Rather than grow exponentially, a naked mole rat's risk of death on any given day, no matter their point in life, hovered around 1 in 10,000. Surprisingly, their mortality risk even fell a little when they grew very old. In this sense, Buffenstein writes, naked mole rats have established themselves as "a non-aging mammal. This life-history trend is unprecedented for mammals," Buffenstein and colleagues wrote in a study published recently in the journal eLife.

A study published in the journal eLife describes three participants that broke new ground in the use of brain-computer interfaces (BCIs) by people with paralysis. One of the participants, a 64-year-old man paralyzed by a spinal cord injury, "set a new record for speed in a 'copy typing' task," reports IEEE Spectrum. "Copying sentences like 'The quick brown fox jumped over the lazy dog,' he typed at a relatively blistering rate of eight words per minute." From the report: This experimental gear is far from being ready for clinical use: To send data from their implanted brain chips, the participants wear head-mounted components with wires that connect to the computer. But Henderson's team, part of the multiuniversity BrainGate consortium, is contributing to the development of devices that can be used by people in their everyday lives, not just in the lab. "All our research is based on helping people with disabilities," Henderson tells IEEE Spectrum. Here's how the system works: The tiny implant, about the size of a baby aspirin, is inserted into the motor cortex, the part of the brain responsible for voluntary movement. The implant's array of electrodes record electrical signals from neurons that "fire" as the person thinks of making a motion like moving their right hand -- even if they're paralyzed and can't actually move it. The BrainGate decoding software interprets the signal and converts it into a command for the computer cursor. Interestingly, the system worked best when the researchers customized it for each participant. To train the decoder, each person would imagine a series of different movements (like moving their whole right arm or wiggling their left thumb) while the researchers looked at the data coming from the electrodes and tried to find the most obvious and reliable signal. Each participant ended up imagining a different movement to control the cursor. The woman with ALS imagined moving her index finger and thumb to control the cursor's left-right and up-down motions. Henderson says that after a while, she didn't have to think about moving the two digits independently. "When she became facile with this, she said it wasn't anything conscious; she felt like she was controlling a joystick," he says. The man with the spinal cord injury imagined moving his whole arm as if he were sliding a puck across a table. "Each participant settled on control modality that worked best," Henderson says. You can watch a video about the study here.

New submitter baalcat quotes a report from Neuroscience News: A new study in mice shows that increasing serotonin, one of the major mediators of brain communication, affects motivation -- but only in certain circumstances. Furthermore, the study revealed that the short and long term effects of increased serotonin levels are opposed -- a completely unforeseen property of this neurotransmitter's functional system. A surprising behavioral effect, discovered in mice by neuroscientists at the Champalimaud Centre for the Unknown (CCU), in Lisbon, Portugal, strongly suggests that serotonin is involved in a biological mechanism which affects the animals' motivation. The study has now been published in the online open access journal eLife. Serotonin, one of the chemical "messengers," or neurotransmitters, in the brain, is used by neurons to communicate with each other. It plays an important role in the regulation of sleep, movement and other behaviors which are essential for animal survival. But for motivation in particular, it was unclear whether serotonin was involved. Using optogenetics, the team stimulated the release of serotonin from neurons in the raphe nuclei. They first induced "peaks" of serotonin by stimulating these neurons with pulses of light, lasting three seconds every ten seconds, over three five-minute time periods. The mice, placed in a box, were left free to explore their environment. In these conditions, their most frequent spontaneous behaviors are walking around, rearing, grooming, digging holes or keeping relatively still, but nevertheless alert. The only difference the scientists saw was that stimulation caused the mice to reduce their locomotive speed by about 50%. In general, this stimulation of serotonin-producing neurons did not affect other behaviors. The effect of these serotonin "peaks" on locomotion was almost instantaneous (speed reduction manifested one second after stimulation) and transient, with things going back to normal after five seconds. But during this short period of time, "the animals acted as if they weren't motivated," says Zach Mainen, who led the study.

New submitter Neuronaut137 writes: Last year a paper in Science magazine reported that humans can distinguish a trillion different odors, a result that had already made its way into neuroscience and psychology textbooks. Two new papers just published in eLife overturn that result, pointing to fatal flaws in experimental design and data analysis. Oh, well; thinking I had a superpower was fun while it lasted.

Rambo Tribble writes A recent study from Denmark has determined that porpoises, dolphins and whales can focus the sounds they make, described as "clicks and buzzes", when hunting. This appears to exceed even the capabilities of bats. One researcher described the ability as, "like adjusting a flashlight." The BBC offers approachable, and illustrated coverage.