It is often said that women and men are more different than similar. That’s not even mostly true; women and men are pretty similar. But there are a few spheres in which there are strong gender differences. One of them is sex.

Men want sex more than women do. (While I am sure that you can think of people who don’t fit this pattern, my colleagues and I have arrived at this conclusion after reviewing hundreds of findings. It is, on average, a very robust finding.) This difference is due in part to the fact that men, compared to women, focus on the rewards of sex. Women tend to focus on its costs because having sex presents them with bigger potential downsides, from physical (the toll of bearing a child) to social (stigma).

Accordingly, the average man’s sexual system gets activated fairly easily. When it does, it trips off a whole system in the brain focused on rewards. In fact, merely seeing a bra can propel men into reward mode, seeking immediate satisfaction in their decisions.

Most of the evidence suggests that women are different, that a sexy object would not cause them to shift into reward mode. This goes back to the notion that sex is rife with potential costs for women. Yet, at a basic biological level, the sexual system is directly tied to the reward system (through pleasure-giving dopaminergic reactions). This would seem to suggest a contrasting hypothesis that perhaps women will also shift into reward mode when their sexual system is activated.

Anouk Festjens, Sabrina Bruyneel, and Siegfried Dewitte, researchers in Belgium, wanted to test this idea. But first they needed to find a way to activate women’s sex drive. Women, more than men, connect sex to emotions. Festjens and colleagues therefore used a subtle, emotional cue to initiate sexual motivation – touch. Across three experiments, Festjens and colleagues found that women who touched sexy male clothing items, compared to nonsexual clothing items, showed evidence of being in reward mode.

Women participated in the first two experiments. They were randomly assigned to handle a pair of men’s boxer shorts or a t-shirt, ostensibly to help a retail store determine why clothes are appealing. The signs of being in reward mode were how much women valued the present (over the future) and how much they valued rewards (over costs).

Valuing the present was measured by the amount of money women said would be required in order to be compensated for not getting a certain amount of money right then. Higher amounts needed to delay were taken as signs of valuing the present. As predicted, women who touched boxer shorts, compared to t-shirts, said they needed more money to defer payment. They emphasized the present.

Another way Festjens and colleagues looked for evidence of being in reward mode was prioritizing rewards over costs. Generally, people weigh costs more than rewards, a principle called “bad is stronger than good.” Being insensitive to losses is one factor that can weaken the bad is stronger than good effect, because losses don’t seem so painful. This logic led Festjens and colleagues to predict that if touching boxer shorts shifts women into focusing on rewards, they won’t be as bothered by the potential for losses.

That is what they found. Women who touched boxers or t-shirts were given a gamble to measure sensitivity to losses. After being given a reward, such as chocolate candies, they were presented with a gamble that involved the possibility to win more chocolates or lose some of what they had been given. The outcome was how much money women required in order to participate in the gamble. As predicted, women who handled men’s boxer shorts, and therefore were in a sexual state, indicated that they would need less money to enter the gamble than did women who handled men’s t-shirts. Touching boxer shorts made the potential rewards of the gamble more enticing than the pain of the potential losses.

The last experiment tested both men and women, and compared how tactile and visual cues matched up. Was seeing a bra (for men) or boxer shorts (for women) enough to trigger reward mode? Men and women touched sexy clothing (bra or boxers), or saw them, or touched a t-shirt. Then they rated how much they would pay for various products, two of which were rewarding — wine and chocolates. Higher willingness to pay indicated a stronger desire, and thus more reward-seeking. Men indicated a higher willingness to pay, and therefore showed more reward-seeking, after both seeing and touching the bra, compared to the t-shirt. Women showed reward-seeking only after touching the boxers. Seeing was not enough.

So in the end, are women and men more the same than different? The answer is yes. (Or, in a favorite phrase of academics, “It depends!”) Women and men’s motivations are more the same than different. Women and men need to survive and want to thrive. Sex is a big part of those motivations. How they go about satisfying those motivations is different. Men can easily shift into reward mode in the presence of sexual stimuli, whereas reward mode comes online when women connect sex to emotions (through touch). Once the reward aspect of sexual desire has been activated, though, men and women once again are more the same than different.

In the end, men can get turned on and their brains eager for rewards by just seeing sexy things, whereas women need to be close enough to the sexy things to touch them. Hence, perhaps, the widespread gender differences in consumption of porn.

Are you a scientist who specializes in neuroscience, cognitive science, or psychology? And have you read a recent peer-reviewed paper that you would like to write about? Please send suggestions to Mind Matters editor Gareth Cook, a Pulitzer prize-winning journalist and regular contributor to NewYorker.com. Gareth is also the series editor of Best American Infographics, and can be reached at garethideas AT gmail.com or Twitter @garethideas.