I really have to take exception to the idea that psychological theories about human nature are "basically fact." Scientific theories change all the time, especially in the softer (non-empirical) sciences like psychology. In particular, some of these theories about the differences in male and female "stimulus and response" have taken on an air of scientific urban legend in the way that they have filtered down into popular culture. It is reasonable to ask what kind of observations these theories are based on, and if the conclusions drawn from them are warranted. These ideas appear to be traceable to studies which attempted to measure the level of sexual response that male and female subjects experienced when shown sexually explicit (pornographic) images. The methodology of such studies is dubious since they do not reflect the real-life conditions of normal human relationships (and certainly have nothing to do with the way that people interact in social nudist situations.) All that one can safely and reasonably conclude from these studies is that (in general) men have a greater sexual response to porn than women do - not exactly an earth-shattering conclusion. One would have to make some pretty big assumptions though, about the nature of human beings in order to extrapolate from the actual data of this type of study to the kind of conclusions which seem now to have become part of popular consensus. It is now treated as common knowledge that the major, driving component of male sexual response is visual stimulus. But does the actual data from these studies warrant such conclusions? Only if one holds a certain reductionist view of human nature. The type of studies cited would tend to confirm the assumptions of evolutionary psychologists who's conception of human beings is purely physicalist. That is, that humans are merely physical (though highly complex) and are therefore determined - behavior (output) is ultimately determined by stimulus (input) from outside, initiating bio-chemical changes within a human organism from the prior state that existed in that individual. This conception of humanity leaves no room for volition or true libertarian free choice - human behavior is reduced to a merely physical/chemical chain of causal events. (Evolutionary psychology is the source of the idea that the differences in male and female human behavior are "hard wired" into us though sexual selection.)
Christians have historically held the view that humans have a dual nature, having a spiritual (soulish) component as well as a physical one (the body) and it is the soul that directs the behavior of the body. Indeed this is this view of humanity assumed by the texts of both the old and new testament scriptures. This classical Christian concept of substance-dualism brings with it a whole bunch of attendant ideas which present-day science under the reining paradigm of neo-Darwinism eschews, but which make much better sense of what we can readily observe in the world around us. Volition, free will, consciousness itself, and the possibility of life extending beyond the death of the body are all concepts that physicalism cannot (even in principle) account for. In addition to a number of good philosophical arguments for it, simple introspection about our own personal experience of an internal "self" gives us a common-sense intuition that this dualistic characterization of human nature is correct. If it is correct, and one assumes a perspective of Intelligent Design, we can reach some important conclusions from our personal experiences: God designed our bodies to be trainable to do various tasks though repetition. This is how we can learn to walk, ride a bicycle, drive a car or play a musical instrument. When we have practiced them enough, we can perform these tasks practically without thinking. Here is where all of this relates to the discussion of male and female participation in social nudism.
Let us lay aside the claim that women are "stimulated aurally" as it is less relevant. The more relevant claim is that men are more attracted to nudism because they are "wired" for visual stimulation. First of all, it only takes a little thought to dispel the idea that "visual stimulation" is a necessary component of male sexual response - if this were so, no-one would ever be able to make love in the dark. No, evolution hasn't "wired" men to respond sexually to visual stimulation, however in our modern western culture, a great many men have "wired" themselves by the decisions they have made. Remember, I said that God has designed our bodies to be trainable through repetition? In our culture that shuns simple nudity, yet consumes massive quantities of pornography, men who repeatedly use porn to sexually stimulate themselves are literally training their bodies to respond sexually to visual images. Men who live in cultures where nudity is common, don't have a sexual reaction whenever they see an exposed female breast. Men who do not use porn and who's primary experience of other naked human beings is in the context of social nudism where rules of behavior apply, are repeatedly "practicing" civil, non-sexual behavior toward others who are in their created state (naked). Christians who criticize nudism on the basis that "male sexuality is visually driven" have (probably unwittingly) sided with the evolutionary psychologists. Their criticism would be valid if the claim were true. But it can only be true if evolutionary psychologists are correct in their physicalist conception of human nature, which would tend to undermine many (even most) of the doctrines biblical Christians hold dear. I don't believe they are correct. I think my understanding of human nature (call it a Substance-Dualism/Intelligent Design/Body-Training view) makes a much better accounting for the-world-as-it-really-is. It also accounts for this universal testimony of practicing social nudists: far from creating occasions for heightened sexual tension and sexualized behavior, social nudism actually acts to demystify and de-sexualize the body. As such it may actually promote a healthier (even more moral) sexuality.
As for the real reasons that fewer women are attracted to nudism (at least on their own, without the encouragement of some significant male in their lives), I think it may have more to do with social conditioning. Women in our society seem to be under much greater pressure to be concerned about how they appear to others (both men and other women). In such a culture, it cannot be discounted how much clothing and make-up figure in most women's self-identity. Then, there are certain inherent differences between the sexes that are (at least in my view) God ordained. In terms of judging between the risk or payoff of a given action, women tend to be more protective (part of their nurturing nature) and men more adventurous (part of their drive for productivity).
-Gregg Gatewood