Forty years ago, the American public suddenly faced an unsettling question: could subliminal persuasion be used to influence the unsuspecting? The anecdotal evidence seemed to confirm the Big Brotherish power of undetected commands slipped "beneath the threshold of awareness." The Central Intelligence Agency, then in the midst of a multi-million dollar mind war research program, was intrigued by the potential power of subliminal messages. Classified documents released decades after these events reveal an obscure and intriguing chapter in the CIA's long involvement with techniques of mental manipulation.

As the CIA learned, the effectiveness of subliminal communication is very much open to question. Even today, the scientific community continues to debate whether subliminals, which are messages too brief to be noticed by the viewer or listener, have any impact at all.

When the CIA peered into the power of subliminal persuasion, what did it find? The best available evidence is the surviving documentation on the CIA's research programs. These records have surfaced sporadically since the mid-1970s, when Congressional investigators and investigative reporters probed into some of the agency's notorious experiments in mind and behavior control.

A few years ago, the CIA began declassifying back copies of Studies in Intelligence, its internal journal on the history and methodology of the spy trade. At last the public can read what is probably the agency's first assessment of "The Operational Potential of Subliminal Perception." A report bearing this title appeared in the CIA journal's Spring 1958 issue.

We don't know when -- if ever -- the CIA quit investigating subliminals, but thanks to this recently released document, we know what piqued their interest. The date of the report is significant; at that time, the United States was in the midst of the first great "subliminal scare" (see Dossier's documented feature on the evolution of this phenomenon).

It began in late 1957, when New Jersey marketing specialist James Vicary claimed to have increased concession sales by flashing too-brief-to-be-seen messages like "Hungry? Eat Popcorn" and "Drink Coke" in the midst of feature films. Vicary later downplayed the effectiveness of the technique, and admitted that his research data on subliminal projection was "too small to be meaningful." But the damage was done. Subliminal mania spread like wildfire across the national consciousness, as people began to wonder, "What do I see that I don't notice, and what can it do to me?"

The concern spread to Washington, D.C., where legislators led by Utah Representative William Dawson started a drive to ban subliminal broadcasting, which he called the "secret pitch." Dawson spoke of the "frightening aspects" of subliminals. "Put to political propaganda purposes," he warned, subliminal communication "would be made to order for the establishment and maintenance of a totalitarian government."

Was Dawson right about the brainwashing potential of subliminals? Could propaganda be secretly delivered and imprinted on the psyche? Down the street from Capitol Hill, at CIA headquarters, some spy scientists were actively exploring such questions.

Martin A. Lee, co-author of Acid Dreams: The Complete Social History of LSD, revealed some of this research in an article called "The CIA's Subliminal Seduction," which appeared in the February 1980 issue of High Times magazine. Lee quoted an unnamed "former CIA operative" as saying that "some thought was given to whether or not we could affect political outcomes by using subliminal perception on things like radio and TV." One partially declassified CIA document cited by Lee contained the ominous observation that "it may be that subliminal projection can be utilized in such a way as to feature a visual suggestion such as 'Obey [deleted].'"

The document, dated January 17, 1958, said that the ssubliminal method "has achieved some success in commercial advertising" and cited James Vicary's now-discredited movie experiments as proof. According to Lee, the CIA then staged in own tests in American movie theaters. "On one occasion, the agency admonished an audience in Alexandria, Virginia, to 'buy popcorn,' but instead, many of the viewers lined up at the drinking fountains because the suggestion made them thirsty," Lee rreported.

The CIA's subliminal experiments on unwitting Americans, alarming as they may seem, were hardly an extreme example of the abuses that the agency's scientists committed. By 1958, the CIA had already spent at least five years testing ways to breach the mind's defenses. CIA Director Allen Dulles had in 1953 launched MKULTRA, a super-secret set of experiments on the science and techniques of mind and behavior control. The program examined everything from sensory deprivation to hypnosis to drugs like LSD.

Amidst this adventurous era that was the dawn of the "Cold War on the mind," as author John Marks calls it, the declassified Studies in Intelligence report on subliminals seems tame and cautious. Richard Gafford, the author of the report, brought a skeptical approach to the subject, and he raised many hard questions for those who take for granted the power of subliminals.

The report directly criticizes Vicary's claims of subliminal success. "It is evident that there are several mighty leaps in logic in the advertising man's argument, and a great many places where his scheme can go astray," Gafford wrote. "He has taken several psychological phenomena which have been demonstrated to a limited degree in controlled laboratory experiments and strung them together into an appealing argument for a 'technique.'"

Gafford did not reject the feasibility of subliminal communication outright. The CIA was rather open-minded when it came to unconventional psychology, after all. "Interest in the operational potential of subliminal perception has precedent in serious consideration of the techniques of hypnosis, extrasensory perception, and various forms of conditioning," he noted. "By each of these techniques, it has been demonstrated, certain individuals can at certain times and under certain circumstances be influenced to act abnormally without awareness of the influence or at least without antagonism."

Ultimately these methods -- "although they occasionally produced dramatic results" -- proved unreliable, the report says. The subliminal tactic was likewise fraught with difficulties. It was too hard to identify and test indicators of the effects of secret stimuli, and probably impossible to standardize a technique that would succeed with most people.

The Studies in Intelligence report concluded with a dim view of the effectiveness of the projection technique that was still spooking the nation: "there are so many elusive variables and so many sources of irregularity in the device of directing subliminal messages to a target individual that its operational feasibility is exceedingly limited."

Did the story of the CIA and subliminals end with Richard Gafford's skeptical assessment? Absolutely not, according to other declassified evidence. Gafford may or may not have been aware of the MKULTRA project, knowledge of which was off limits for all but a handful of CIA officials. His report, therefore, is best viewed as one piece of multi-dimensional puzzle; it represents one CIA officer's take on subliminals, but tells us little about how far the agency's mind control investigators may have gone with the technique.

One CIA memo written shortly after Gafford's report appeared in Studies in Intelligence shows that the agency wasn't done with subliminals. On April 18, 1958, Dr. Sidney Gottlieb, the scientist who administered the various MKULTRA projects, summarized Subproject No. 83, which financed "technical surveys" of "controversial and misunderstood areas" such as ESP, hypnosis, truth drugs, and yes, "subliminal perception." (Click here to read the document.)

Whatever conclusions the CIA drew from the MKULTRA subliminal survey are not publicly known. Would the CIA have shied away from using subliminals on operational targets? The legacy of the MKULTRA experiments strongly suggests not. Time and time again, techniques developed under the auspices of the program were applied in Cold War covert operations.

The presently available documentation does not say when (or if) the CIA quit investigating and/or using subliminals. However, Congressional investigations revealed that MKULTRA scientists tested several severe techniques on unwitting citizens that made subliminal manipulation seem like a walk in the park. So when it comes to the CIA and subliminals, we can be sure of one thing: the agency's mind molders would not have rejected subliminal persuasion operations on ethical grounds.