EEG Biofeedback and Maintaining Functional Integrity on Long Duration Space Missions
When human beings are placed in a strange environment where the workload is extreme and the threat of destruction is omnipresent, the level of arousal in the human nervous system tends to remain above a certain threshold. It is, essentially, a milder version of what happens with Post Traumatic Stress Disorder where situational events or conditions reset the physiological set point for the alarm response in the brain. A prolonged state of overarousal leads, ultimately, to a state of exhaustion in the brain that has distinct features in the EEG (or brainwave activity). Typical symptoms that accompany this state of cortical exhaustion are: depression, insomnia, attentional deficits, mood instabilities and, ultimately, immune system irregularities and physical illness. Brain waves are reflected micro changes in electrical potential taking place in the cortex (measured at the scalp's surface). They represent synchronous firings of neurons located in specific areas of the brain. Although the EEG contains no useful information about the specific "content" of cognitive processes or of thoughts in general, it does register changes in states of physiological arousal, attention, and even of mood. Over the past 30 years or so, researchers have demonstrated that teaching a person to deliberately alter their EEG, through such techniques as operant conditioning via EEG biofeedback, can be very effective in treating problems involving disregulation in the dimensions of arousal, attention and mood. With the beginning of operations aboard the ISS, we begin a transition towards long duration space missions where maintaining functional integrity will become a crucial issue. If lessons aboard the 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.