Gone are the days when renting an X-rated movie required walking into a roped-off room in the back of a video store and eyeing a centerfold meant facing down a store clerk to buy a pornographic magazine. Now pornography is just one Google search away, and much of it is free. Age restrictions have become meaningless, too, with the advent of social media. One in five teenagers has sent or posted naked pictures of themselves online, according to the National Campaign to Prevent Teen and Unplanned Pregnancy.

With access to pornography easier than ever before, politicians and scientists alike have renewed their interest in deciphering its psychological effects.

People who raise critical questions about pornography and the sex industry often are accused of being prudish, anti-sex or repressive, but just the opposite is true. Such questions are crucial not only to the struggle to end sexual and domestic violence, but also to the task of building a healthy sexual culture. Pornography can be a teacher, a releaser and a trigger of behaviors. For example, a male masturbating to the images of smiling children having sex with adults, or of sexually aroused women being beaten, raped or degraded, is learning that the subjects enjoy and desire this treatment and is thereby being taught that he has permission to act this way himself. Some of pornography’s messages about relationships, sexuality and women may be damaging, even if the pornography is not illegal or pathological. This learning produces effects in attitudes toward sexual violence, relationships, the attractiveness of a partner and women’s liberation, and in sexual violence behaviors, pedophilia, sexual harassment, domestic violence, prostitution, sexual deviance, drinking and physically risky behavior.

The rape myth is a set of beliefs that women are responsible for rape, like to be raped, want to be raped and suffer few negative outcomes because of it. The increase in attitudes supporting sexual violence following exposure to pornography is greater if the pornography is violent than if it is non-violent. A similar effect is seen even when the pornography is not violent. Males who are shown non-violent scenes that sexually objectified and degraded women and were then exposed to material that depicted rape indicated that the rape victim experienced pleasure and “got what she wanted." Even women who were exposed to pornography as a child have a greater acceptance of the rape myth than those who were not. Those exposed to pornography recommend a sentence for a rapist that was half of that recommended by those who had been shown non-pornographic imagery. These subjects appear to have trivialized the crime of rape.

Rape pornography teaches men that when a woman says no, the man does not need to stop.

Pornography makes violence sexy.

The likelihood of forcing a woman sexually was correlated with the use of hard core, violent and rape pornography. The likelihood of raping a woman was correlated with the use of all types of pornography, including soft-core pornography. The correlation between rape rates and circulation rates for eight pornographic magazines indicated that states with higher circulation rates had higher rape rates. These magazines being: Playboy, Penthouse, Chic, Club, Forum, Gallery, Genesis and Oui.

Pornography’s effect depends not just what you are exposed to but also how often. The more frequently men used pornography and the more violent the pornography they used, the more likely they were to coercive others into sex, including to use of physical coercion (i.e., rape).

Pornography’s effect also depends upon individuals’ characteristics as well as their use of pornography. Males who were high in hostile masculinity and sexual promiscuity, and who used pornography frequently, were significantly more likely to have physically and sexually aggressive tendencies than males who were low in these factors.

According to a study conducted by the National Victim Center, 1.3 women age 18 and over in the U.S. are forcibly raped each minute -- 78 per hour; 1,871 per day or 683,000 per year.

These numbers are too high. It's 683,000 above what it should be, which is zero. Education begins in the home. If the parents do not educate their children about sex, then the Internet will, and these numbers will continue to double. Fighting sexual violence starts at home.