The chief goal of the present study was to test whether exposing young adult males to female centerfold images causes them to believe more strongly in a set of beliefs clinical psychologist Gary Brooks terms "the centerfold syndrome." In addition to testing the straightforward effect of exposure to centerfold images on males' centerfold syndrome beliefs, the present study explored the moderating potential of three variables: sexual explicitness of the centerfold images, males' past exposure to objectifying media, and recency of exposure to the centerfold images.Participants were randomly assigned to either a control condition that did not feature centerfold stimuli, a "nonexplicit" condition that featured female centerfolds who did not expose their nipples or genitalia, or an "explicit" condition that featured female centerfolds exposing either their nipples, genitalia, or both. Past exposure to objectifying media was assessed by asking participants how frequently they viewed pornography in the prior year. Items indexing the five centerfold syndrome beliefs - voyeurism, sexual reductionism, masculinity validation, trophyism, nonrelational sex - were administered immediately after exposure and approximately 48 hours after exposure.Exposure to centerfold images had an immediate strengthening effect on the sexual reductionism and nonrelational sex beliefs of males who view objectifying media about once a month or less and this effect persisted approximately 48 hours after exposure. Likewise, exposure to centerfold images had an immediate strengthening effect on the masculinity validation beliefs of males who view objectifying media about once a month or less, and this effect persisted at a marginally significant level approximately 48 hours after exposure. No difference were found between males exposed to nonexplicit vs. explicit images.These findings are consistent with a growing body of literature indicating that mainstream media sex can affect the sexuality of young people. Furthermore, the findings of the present study affirm the suspicions of some that objectifying depictions of females affect the sexual beliefs of some males in ways that are likely unrelated to sexual aggression but are still antisocial.