Photo: Mike Hutmacher/Wichita Eagle/TNS

The Supreme Court’s June 26 ruling legalizing same-sex marriage nationwide may have registered as a transformative moment in and of itself, but it also served as the culmination of one of the more massive — and rapid — shifts in public opinion in recent history. In 2005, just 36 percent of Americans favored allowing gay and lesbian people to marry legally. By the time of the decision it was 57 percent, and, when asked, straight Americans now express more positive attitudes toward those groups than ever before.

But what about how people actually feel, not just what they say? It’s easy to say you don’t harbor prejudice against some group, but how would you react when placed in a situation where you had to make a split-second decision, one that might betray your true feelings?

A study released Thursday in the journal Collabra sheds some light on how real the newfound goodwill toward gay and lesbian people is when push comes to shove. Between 2006 and 2013 — a period of many state-level ballot measures and court cases on same-sex marriage — a team led by Erin Westgate of the University of Virginia studied the attitudes, both explicit (how people reported they felt) and implicit (how they unintentionally demonstrated they felt), of 683,976 people toward those groups through online surveys. The responses suggest that implicit prejudice has weakened substantially since 2006, but at a far slower pace than self-reported bias. That is, some people haven’t made as much progress as they think they have, or they now think it’s socially unacceptable to say how they really feel.

To discover respondents’ implicit attitudes, the researchers used implicit association tests, or IATs. As a previous Science of Us article explains, in most common versions of IATs, “words or images are briefly flashed, ‘priming’ subjects to respond to subsequent stimuli — if you’re quicker to pair a black face with the word criminal, to take a hypothetical example, you’re exhibiting more implicit bias. Researchers think these effects extend out of the lab into everyday interactions.”

After sifting through the mountains of data, the authors found that explicit preference for straight people over gay and lesbian individuals was 26 percentage points weaker in 2013 than in 2006. That’s a significant movement toward acceptance and more or less mirrors the 21-point gain that support for marriage equality made during roughly the same period (2005 to 2015). Implicit preferences made just half as much progress — 13.4 points — in the same period, though this was in itself groundbreaking: According to the study write-up, it was “the first documented evidence for a cultural shift in implicit evaluations about any topic.”

“I was actually pretty pessimistic, I didn’t think we would see a difference,” said Westgate. “Then I actually got all the data together and looked at it for the first time and saw that slight downward trend, and I thought, Wow, something’s really happening here.”

Implicit attitudes are supposed to reflect what people are genuinely feeling, their gut response when forced to react quickly to something. The 13-point shift represents a meaningful change in how straight people feel, viscerally, about gay and lesbian individuals, if the established science of IATs is to be believed. But the question remains: Why is there still such a big gap between how people say they feel and how they actually do?

Westgate speculates that there are a number of factors in play. Some respondents might be feeling the strain of social pressures: “Maybe people’s attitudes have changed, but they haven’t changed quite as much as they appear to,” she said. “[Their explicit responses] may be due to social pressure and not feeling like it’s okay to tell people that they have these sorts of biases.” Indeed, people are often reluctant to report a socially unacceptable view, a phenomenon called social desirability bias.

It might also be that our attitudes change explicitly first, but it takes longer for those feelings to really take root at a gut level. “Imagine someone reading about, say, some horrible workers’ treatment at some company that they really like,” offers Westgate. “They explicitly decide, ‘Okay, I don’t like this company anymore, I don’t want to support it,’ but their gut feelings, they trail that. It may take some time for that to actually be internalized to a certain extent.” That might explain why we all keep buying iPhones, despite the revelations of labor abuses and dangerous working conditions in the Chinese factories that produce them.

A few groups in particular illustrate the gap. Survey participants who were black, male, conservative, or older showed the strongest preference — explicit and implicit — for straight people over gay ones when the study began in 2006, and also showed the biggest shift in explicit beliefs toward a more tolerant stance. Implicitly, however, these groups’ feelings changed very little: “For black participants, that was one of the only groups that we really didn’t see any real large evidence for change during that period,” says Westgate. “You know, it’s not a comprehensive sample, of course, but it does suggest that maybe groups as a whole that are higher in bias to begin with, we do see a lot of explicit change, but we don’t see a lot of implicit change, and logically we can infer that there probably is a growing gap between what they’re saying explicitly and what they’re feeling.” It seems likely that these groups felt the cultural sea change regarding the acceptance of gay people and the social pressure that came with it, but, per the study’s analysis, their implicit views lagged a bit.

The study paints a clear picture: A profound cultural shift has occurred, and individual attitudes held at the gut level are following a lap or two behind. Even if the shift is occurring at different paces among different groups, anti-gay prejudice is indisputably waning.