Jim Henry's world revisited--environmental "stress" at the psychophysiological and the molecular levels.

Abstract

Ever increasing applications of sophisticated technologies in western civilization have placed great and growing demands for the rapid and accurate processing of multi-modal sensory information. These information streams may exceed an individual's performance capabilities. Failure to respond appropriately may have serious consequences, not only for the individual but also for others, as in command situations in the aerospace environment. There are, for example, consistent patterns common to EEG records in a population of astronaut candidates, when exposed to increasing visual information overload, simulating hazardous flight conditions. The records are dominated at the point of "information overload" by sharply and progressively increased theta wave (4-7 Hz) activity in temporal regions, major increments in frontal beta (> 14 Hz) activity, and markedly reduced occipital alpha (8-12 Hz) levels. These responses to a simulated stress raise questions about the brain's ability to distinguish natural reality from the mediated reality in modern life. It has been hypothesized that an individual's reactions with computers, television and new media are fundamentally social and natural, just as in interactions in real life. Also immune responses may here offer valuable benchmarks concerning reactions to mentally stressful stimuli. Another type of environmental influences in modern society is that of electromagnetic fields. Even fairly weak (athermal) electromagnetic fields have proven to be useful tools to study regulatory mechanisms in cells from brain and other tissues. There is growing evidence that nitric oxide may influence normal EEG patterns and that it may also participate in the pathophysiology of oxidative stress disturbances, including influences in e.g. Parkinson's and Alzheimer's diseases, then behaving as a free radical with reactive-oxygen-species or reactive-nitrogen-species. As a free radical, nitric oxide is sensitive to a variety of imposed magnetic fields, with theoretical and experimental evidence that its actions in regulating the rate and amount of product of cerebral biochemical reactions may also be modulated by imposed magnetic fields.