The Space Reviewin association with SpaceNews

ISS crew
The ISS provides a platform for researchers to understand and mitigate the physiological and psychological effects of long-duration spaceflight. (credit: NASA)

Human factors and the new Vision for Space Exploration

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Over the past 30 years or so, researchers have demonstrated that teaching a person to deliberately alter their electroencephalogram (EEG), through such techniques as operant conditioning via EEG biofeedback, can be very effective in treating problems such as attention deficits, mood instabilities (anxiety, mania, and depression), and behavioral problems. Additional benefits are consistently observed in sleep. The major advantage of such an intervention over the usual pharmacological approach is that the training is essentially without side effects.

EEG biofeedback has been used with particular success with attention deficits. The corrective mechanism seems to involve training of the subcortical regulatory centers in the brain that govern attention and focus. Attention deficits can also be situationally induced through exhaustion and hyper-focus. In other words, normal brains, (i.e. those without any predisposition towards attentional disorders) will begin to exhibit some of the EEG characteristics of attention deficit disorder if the person is exposed to an unrelentingly stressful situation that compels constant external vigilance and anticipation. Whether due to biological factors or exhaustion, the common feature of poor attention is an excess of low-frequency activity. Down-training these low frequencies and boosting the midrange activity seems to improve the brain’s regulatory activity and the attentional problems are resolved. Part of this is due to a normalizing of sleep patterns.

Radiation exposure causes a cascade of free radical proliferation within the body leading to effects that resemble accelerated aging. The immune system tends to suffer the worst damage.

More recent EEG research by psychologist Barry Sterman of UCLA indicates that performance is highly correlated with certain EEG patterns. Ten years ago several pilots at Edwards AFB were studied for the purpose of examining the EEG correlates of peak performance while engaging in flight simulator tasks that required intense and sustained mental focus. It was discovered that those pilots whose brains produce more 8–12 Hz activity between tasks perform significantly better than those whose brains produce less. The subjects who produced the greatest amounts of this activity also showed less fatigue and greater endurance. Preliminary evidence in my own research also suggests that this EEG behavior occurs during and between maneuvers in actual flight. Most importantly, research indicates that such desirable EEG signatures can be trained through biofeedback. In addition, those persons who have received such training report reductions in anxiety and depression as well as improvements in attentiveness and social compatibility.

Other forms of biofeedback (such as galvanic skin response, heart rate variability, and peripheral temperature) are also effective in reducing stress related anxiety.

Antioxidant vitamins

Another potentially powerful countermeasure against stress is the use of antioxidant vitamins. These are nutritional supplements that counter the cellular damage done by free radicals, highly reactive molecules (with an unpaired electron) that readily join with and do damage to the tissue cells of the body through oxidation. Free radicals alter the charge distribution on the cell membrane resulting in “crosslinking”, which leads to aging of the tissue and, ultimately, a deterioration in function. With all of the radiation bombardment in space, long-term exposure could lead to a serious compromising of the organs of the body. Radiation exposure causes a cascade of free radical proliferation within the body leading to effects that resemble accelerated aging. The immune system tends to suffer the worst damage. In addition, the stress of long-term spaceflight leads to the chronic release of the fight-flight corticosteroid known as cortisol. Long-term sustained release of this hormone leads to a compromised immune system and circulatory system damage. Antioxidant vitamins, vitamin C in particular, tend to shield the tissues from such damage.

The ISS as a platform for research

With the beginning of operations aboard the International Space Station in 1999, we began a transition towards long-duration space missions where maintaining functional integrity has been and will become an increasingly crucial issue. If lessons aboard Mir are any indication, long-term flights will tend to tease out and expose our weakest links as the ability to endure extended periods of isolation under heavy work load conditions in microgravity is stretched to the limit.

Robert Zubrin states that the human psyche will not be the weak element in the loop on the trip to Mars. This will only be the case if we address the issue squarely.

The ideal venue for carrying out such research is the ISS. Orbital real estate is extremely sparse, not to mention expensive. As such, it would behoove us as a nation not to be impulsive with respect to cost-cutting when the time comes to consider its fate. The reallocation of resources, which is sure to occur with the Vision for Space Exploration now in the works, will likely bring more financial pressure to bear on the station. The fault is not with NASA, but with the budgeting straightjacket they are expected to work within. Cost overruns are a fact of modern life in a technologically advanced society, kind of like taxes, smog, and credit debt. The ISS can be our steppingstone to the planets. It can teach us how to live and work in space. As such the ISS should be continued and expanded.

Fortunately, the ISS is an open- ended architecture in that its construction is modular. As such, the size, shape, and capability of the ISS can change and expand over time. Specifically tailored research or habitation modules can be added or interchanged. This same approach will likely be employed for future bases on the Moon. This kind of open-ended architecture will help to encourage participation of other nations as well as the US private sector, as the reigns of control are ultimately handed over (at least partially) to private enterprise. A flight to Mars will take meticulous and methodical preparation and planning. Such preparation and research is best done in Earth orbit. You don’t want to be halfway to Mars and realize you forgot the suntan lotion. Thus, preserving our near Earth space outposts will serve us well in the future.

Robert Zubrin states that the human psyche will not be the weak element in the loop on the trip to Mars. This will only be the case if we address the issue squarely. With careful crew selection, advanced preparation, and adequate countermeasures, we can be certain that the human element will not be the weak link in the chain and, in fact, will provide the glue that maximizes the efficiency of the different technologies required for a journey to Mars and beyond. It is crucial that we do our homework before venturing out into deep space. To not do so will be disastrous—not just in terms of the immediate welfare of the explorers, but for the security of our future endeavors in space.