If you’ve ever stayed up too late studying for a test, you know that sleep impacts memory—you need that precious shut-eye in order to encode and recall all that information. But what is it about sleep that aids memory? 

Researchers have pinpointed a specific stage of sleep, REM sleep, as an area of interest for studying memory consolidation. REM, or rapid eye movement sleep, is the same stage in which dreams occur. So researchers at Northwestern University devised a way to communicate with lucid dreamers—people who are aware of their dreams and can control what they do in them—as a way to study how memories get made.

Science Friday producer Katie Feather talks with Ken Paller, professor of psychology at Northwestern University to discuss what lucid dream research has taught us about memory.

Back in 2013, Charles Hoeffer from the University of Colorado Boulder was studying memory and learning in mice. He was looking at a specific protein in the brain called AKT1, which helps mice forget an old task and learn a new one. In humans, a mutation in that protein has been linked to disorders like schizophrenia, Alzheimer’s and depression. 

But in a follow-up study, Hoeffer did something different. He included both male mice and female mice, and then tested them separately. As expected, he discovered that male mice had a much tougher time learning the task when AKT1 wasn’t working. But in female mice, he found the unexpected: It didn’t make any difference whether the protein was removed or not. In other words, the sex of the mouse became an important variable that affected the outcome of the research.

Hoeffer’s study is one example of considering sex as a biological variable (SABV) in pre-clinical research. And in 2016, the National Institutes of Health’s Office of Research on Women’s Health made it an official policy for researchers applying for funding. 

But that didn’t change things overnight. Five years later, the approach is still catching on in many areas of research. Chyren Hunter, from the Office of Research on Women’s Health, joins Ira to discuss the progress that’s been made, and what lies ahead for the effort to make pre-clinical research more inclusive.

Further information on the NIH’s policy on sex as a biological variable is on its website.

“Parachute science” is a term describing how researchers sometimes drop down from an ivory tower in the wealthy Western world into a foreign community for field work. They gather their data, and then zip off home without engaging with or acknowledging the contributions of the local researchers in that community. This week in the journal Current Biology, researchers tried to quantify just how widespread that tendency is in one area of study—coral reefs.Searching through fifty years of publications published on the topic of warm water coral reef biodiversity research, they found that in 22% of the studies on coral reef ecosystems in Australia, there were no Australian researchers included as authors on the publication. The effect was even more noticeable in lower-income countries, such as Indonesia and the Philippines—where 40% of the published studies on coral reefs included no local scientists. 

Ira talks with two of the study’s authors, Paris Stefanoudis and Sheena Talma, about what they found, and how researchers can work to make science more inclusive.

Of the more than 200 million COVID-19 vaccines that have made it to patients’ arms this winter, more than a quarter have gone to people in the United States—a country with 4 percent of the total world population. Just last week, UN Secretary-General Antonio Guterres said that 75% of the world’s vaccinations so far had been in just 10 countries—while 130 countries had not received a single dose. 

Meanwhile, on Wednesday, the nation of Ghana was the first to receive vaccines—600,000 doses—shipped as part of COVAX, a multi-national program which aims to provide as many as two billion free vaccines to poor and middle-income countries by the end of the year.

Ira talks to Yale global health expert Saad Omer about the international effort to move vaccines equitably around the world, and the remaining hurdles for poorer countries.