An apology has been issued. The protests are fading. And it may be tempting to dismiss the uproar over the provocative chimpanzee cartoon in the New York Post last week as just another "race card" dust-up.

But that would obscure an underlying reality captured in the Post situation and demonstrated by research we have conducted: Some racial associations are embedded so deeply that they are difficult to recognize, much less eradicate -- and they continue to shape our behavior and ideas.

The Post cartoon depicted two police officers standing over a chimp they had shot dead in the street. The image directly referenced the killing in Connecticut of a pet chimp that had mauled its owner's friend. But the caption was more oblique: "They'll have to find someone else to write the next stimulus bill."

Many people thought they recognized a hateful association in the cartoon -- between blacks and apes. They were shocked by the ugly possibility that it was equating the violent chimpanzee with President Obama. Some even considered it a veiled invitation to murder the nation's first black president.

In the 19th century and well into the 20th, popular media from movies to fiction to political cartoons frequently portrayed blacks as more simian than human. It was an association that provided cover for slavery itself, as well as anti-black violence. Lynchings in the United States were often justified by relying on this dehumanizing association, and it surfaced in the Rodney King controversy in Los Angeles: LAPD Officer Laurence Powell had referred to a black couple as "something right out of 'Gorillas in the Mist' " moments before he was involved in the King beating. Like nooses, the "N-word" and white sheets, referring to blacks as apelike is among the most violent and hurtful legacies of our nation's difficult racial past.

The negative association -- this linking of two ideas in the human mind -- goes far beyond historical legacy. In multiple studies on ape and African American associations, using different experimental approaches with white and nonwhite subjects, we have found that the link persists and can be triggered in the most egalitarian of people. Our research also suggests a particularly disturbing consequence: When the association was called to mind, even in the absence of conscious awareness, participants in our laboratory experiments were more likely to endorse violence against African Americans.

In one study, for example, we exposed some participants to words such as "chimp," "gorilla" and "orangutan," flashed on a computer screen at such a rapid rate that they could not be consciously detected. Next, we asked all the participants to watch a two-minute videotape of police officers who had surrounded a suspect and were violently subduing him. Some participants were led to believe that the suspect was white; others were led to believe he was black.

What did we find?

When the participants were led to believe that the suspect was white, exposing them to the ape words beforehand made no difference in their judgments about the use of force displayed in the video. However, when participants believed the suspect was black, those who were exposed to the words thought the police officers were more justified in the amount of force they used. They thought that the black suspect deserved the violence that was directed at him.

This finding is made more disturbing by one of the other studies we conducted. It looked into the role of the media in death penalty cases. Using data compiled by the criminologist David Baldus, we examined 153 cases in the Philadelphia area in which a defendant was found guilty and statutes allowed for the application of the death penalty, among other sentencing options.

We read every article published about these cases in the Philadelphia Inquirer, from the time the crime was first reported to the sentencing of those arrested, and we tallied the number of ape-related metaphors that appeared in print -- things such as "an urban jungle" and "aping a victim's screams." Not only were black men and their crimes much more likely to be described in apelike terms, but the number of ape-related metaphors predicted the likelihood that a defendant would be sentenced to death.

It is important to note that in every study in which we measured people's racial attitudes, using varying techniques, those views about blacks did not influence the results. In other words, the measurable presence of anti-black prejudice did not dictate how strongly people associated blacks with apes.

Instead, we believe that even among people who aren't particularly prejudiced, the association between blacks and apes is still strong, held in place through "implicit knowledge," the result of a lifetime of conditioning, rooted in historical representations of blacks as less than human.

All of this suggests that it was not simple racism, or just a desire to liken the creation of the stimulus bill to an out-of-control chimp, that was reflected in the Post cartoon. It was a kind of racial programming, a legacy even something as progressive as Obama's election cannot obliterate.

Social psychologists Phillip Atiba Goff and Jennifer L. Eberhardt are professors at UCLA and Stanford University, respectively.