Even though rats and mice can be trained to do all kinds of lab experiments, run through mazes, and figure out how to get rewards, their intelligence has its boundaries, largely because of the limitations of their tiny brains. But University of Rochester Medical Center researchers wanted to see if they could alter the brains of lab mice by injecting them with human cells. It might sound crazy, but it actually worked—the test mice became smarter than the others.

The research team used glial cells from human fetuses that had been donated to science. Glial cells are much more numerous than neurons. Glia ensure that the neurons function properly by transporting nutrients to neurons, keeping the neurons in place and insulating them, as well as digesting dead ones. The baby mice used in the experiment had their normal mouse neurons, but then the researchers injected them with 300,000 human glia each, which became astrocytes, star-shaped glial cells abundant in the human brain and spinal cord that help strengthen synapses.

Both science fiction and actual science have demonstrated the malleability of memory, from implanting artificial memories to suppressing bad ones. MIT researchers recently added to the body of memory work with their recent publication in Nature about swapping positive and negative memories in lab mice.

Memories are complicated. For one thing, as soon as we experience something, our brains go to work, associating the memory with context, whether it’s emotional or geographical or involving the people surrounding the event. Because memories aren’t exact recordings of what has actually happened (which is what makes eyewitnesses notoriously unreliable), psychologists and scientists have long been toying with it, seeing how they can manipulate people to either create new associations surrounding an event, remember things that had been long buried, or even implant new memories. MIT’s recent study sought to identify the neurological basis for such ideas.

Soon there won’t be any cosmonauts on the ISS, but new residents will soon arrive, and while they might not be as helpful as cosmonauts, they may be cuddlier. Elon Musk calls them “mousetronauts,” and in August they’ll fly to the ISS on a SpaceX Dragon cargo ship to be part of a NASA study on the physiological effects of long-duration weightlessness.

The rodent research focuses on the physiological changes that occur when living for long periods in zero or microgravity. Even though astronauts exercise while on the ISS, they invariably lose muscle, immune system capabilities, and bone density, among other problems. Prolonged stays in microgravity also affect the nervous, endocrine, and reproductive systems, as well as genetic and molecular processes. Researchers believe that studying the mice will help them learn how and why these changes occur.

Regardless of one’s philosophy about the pursuit of immortality, scientists keep making breakthroughs that make that goal seem more plausible. The latest of those efforts are two studies conducted by the Harvard Stem Cell Institute and one by Stanford University and University of California at San Francisco researchers that involved injecting the blood of young mice into older mice to reverse the effects of aging.

The initial methodology seems pretty strange: scientists essentially turned two mice into Siamese twins, attaching an old and a young mouse together via their circulatory systems. The older mouse’s brain and muscles benefited from being conjoined, and after a month stem cells in the brain and muscles of the older mouse became more active and produced more neurons and tissue. But the young mice who were joined up with the old mice had the opposite result — they stopped producing as many new cells, and they began to age faster than they otherwise would.

Scientists and transhumanists like Ray Kurzweil and Aubrey de Grey believe that humans can, should, and will eventually “solve” the problem of aging and death. They believe the human body can be altered on a biological and genetic level and programmed away from age-related decay and disease. It’s a controversial topic, but regardless of your stance on the pursuit of radical life extension and immortality, science has moved one step closer to realizing this goal. For the first time, scientists have regenerated a living organ.

The brain has often been referred to as a computer for its ability to oversee, process, and carry out numerous functions at once. Now, a recent study by scientists at the University of North Carolina Chapel Hill and University College London reveals just how literally true that comparison is. In fact, it seems that the brain is really a supercomputer, as it has tiny computers within it.

The paper, which was published in Nature, focuses on dendrites, which are tiny (one hundred dendrites would comprise the width of a strand of human hair), tree-shaped extensions on neurons that receive information, namely in the form of electrical stimuli, and transfer it to the body of the cell. Scientists have long known that dendrites transfer information, but it turns out they do a whole lot more than that — they actually process information too.