Penn researchers will work with NASA to examine the biological and cognitive differences in twins while one is on Earth and one launches into space.
The researchers’ study, a collaboration among Penn professors Mathias Basner , Ruben Gur and David Dinges , will follow astronaut Scott Kelly as he accompanies Russian cosmonaut Mikhail Kornienko into space for a year, while simultaneously studying his brother, retired astronaut Mark Kelly, who will remain on Earth. The year-long expedition is unprecedented for the International Space Station, where Scott Kelly will live during the study.
“We can detect more subtle changes caused by spaceflight when we compare the genetically identical Kelly brothers,” said Basner, the study’s lead researcher. “Using identical twins potentially allows scientists to separate ‘nature versus nurture’ ... any differences are likely due to spaceflight and not because the two subjects are genetically distinct.”
The study will involve measuring the effects of microgravity and being in space on executive functioning, memory, emotions, social cognition and complex reasoning, among other things. These functions will be studied using a computerized cognitive battery of tests developed by psychology professor Ruben Gur.
Gur said that use of the battery will allow the researchers to “take healthy people and scan them doing cognitive tasks in order to identify brain networks that are recruited in order to perform specific tasks.”
“The battery allows a fairly rapid assessment of a range of up to ten cognitive functions in space flight,” Dinges said . “It’s particularly valuable for understanding whether any of the different brain-based cognitive functions needed for humans to operate effectively are changed in microgravity.”
Basner said blood samples will be collected from the brothers, in addition to the psychological and physiological testing, which will be conducted before the flight to establish a baseline. Samples will also be taken at one month intervals over the course of the year.
The study itself is unique not only in that it will examine twins, but also that it will further analyze longer space missions. Dinges also said the study is unique because it will examine “a whole host of fundamental biology” over the course of a year.
Although biological changes and cognitive processing have been studied extensively before, this idea came from the twin Kelly brothers themselves.
“It was an idea that the brothers brought to NASA,” Dinges said. “Since Scott [Kelly] will be up in space for a year and Mark is a retired astronaut, they said they would be willing to contribute some of their biological samples for studies of the effects of microgravity on biomolecular responses.”
The study is one of the 10 selected proposals chosen out of 40 to receive a combined $1.5 million over a three-year period, Basner said. While NASA is funding and managing the investigations of the study, the National Space Biomedical Research Institute will be assisting NASA in managing the general aspects of the project.
“We want to look at people who are very high-functioning and find out what happens to their performances under various stresses” that they experience in space, Gur said. “[This] is a unique opportunity to learn not just about the effects of stress on cognition and effects of other factors on cognition, but also look at it in identical twins.”