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The idea of the boundless unconscious mind is once again in the spotlight. In order to explain why, we take a romp along the winding road that subliminal research has travelled.

The public has, by and large, supported the idea of subliminal messaging. The willingness to entertain the notion of subliminal messaging, albeit with a load of healthy scepticism, is actually quite extraordinary. This is despite the lack of support from clinicians. For most, Freud’s incarnation of a steamy, incestuous and violent subconscious has found less appeal as has time progressed. Psychodynamic approaches arguably took backstage in favour of the less bizarre and empirical cognitive methods.

Nonetheless, the true potential of subliminal messaging had already captured the imagination of science fiction writers who pumped out good stories, sustaining the willingness to remain open to the idea. (Fatefully, author Leonard Mlodinow wrote for the TV series Star Trek.)  The concept endured not only because the idea felt right intuitively but because its tenets were also supported by our greatest thinkers going back to the year dot. Wundt, Carpenter, Pierce, Jung, Jastrow, James (and let us not forget ancient Greece here) gave claim to the existence of the unconscious and hinted to its potential (Mlodinow, 2012).

When today’s scholars such as Dr. John Bargh (2006, 2012), look over their shoulders, they are greeted with a shift in academic discourse more in tune with public sentiment. They see a slow but sure tide of evidence supporting their ideas which, to some figures in the late 1970s, bordered on the paranormal. Though the waters of evidence remain muddy and confusing to navigate, they are rising rapidly. No longer is the debate centred on the existence of subliminal communication, but on why it works and how it is best induced. The subconscious is no longer considered to be a mysterious, uncontrollable entity within, but an automatic, behind the scenes governor of normal everyday functioning (Bargh, 2012; Mlodinow, 2012).

Fuelled by the growing popularity of subliminal messaging as a potential form of clinical therapy as well as the subject’s penchant for a blistering academic debate, research efforts renewed and matured. The tide swelled.

By the mid-1980s there was already a slew of research in the offing covering specific applications including weight loss (Silverman, Martin, Ungaro, & Mendelsohn, 1978), curing agoraphobia (Lee, Tyler & Horn, 1983), honing the accuracy of darts (Plumbo & Gillman, 1984), and influencing learning potential (Cook, 1985).

The Placebo Effect

The case for subliminal self-help messaging may have been severely weakened by the presence of a strong Placebo Effect. This was best represented by Greenwald, Spangenberg, Pratkanis & Eskena’s study which showed a strong Placebo Effect (1991). This was also supported by a follow up study (Spangenberg, Obermiller & Greenwald, 1992). More recent research underscored the role of the Placebo Effect (Kouider & Dupoux, 2004).

The workings of the Placebo Effect remain to date, one of the most elusive explanations of modern science. The Placebo Effect is used to explain desired change, usually an improvement in a medical condition, even though no treatment is given. In controlled medical testing, sugar pills (called a Placebo) are usually given instead of the real medicine. This is so the study can rule out the Placebo effect. In short, this is improvement as a result that one thinks they are being treated.

For example, depression is cured even though someone is taking sugar pills, thinking they are antidepressants. Stranger still is the lack of improvement reported by people who are administered antidepressants without their knowledge (Brooks, 2009). The Placebo effect is arguably common to all forms of treatment. In the case of the abovementioned studies, respondents reported significant improvement although their actual performance in the assigned task did not. This was no great revelation, as this quandary is also true of widely accepted chemical treatments such antidepressants and pain relief.

Controversially, lacking any scientific evidence, a handful of alternative therapies still exist and are popular, blissfully trading on the Placebo Effect. The purpose of the subliminal research from that moment on was to show that subliminal self-help is not one of them.

Studies such as these would have dampened the debate should they have failed to demonstrate that subliminal messaging had a strong influence upon something invaluable outside the laboratory, self-efficacy. Self-Efficacy refers to the self-perception that one is capable in a particular task. In reality the belief that one can succeed is the strongest determinant of eventual success, and often what subliminal self-help programmes are used for.

The debate chimed throughout the nineties and into the noughties. The tide of empirical support ebbed and flowed. The previously mentioned Placebo findings were refuted by the Hudesman, Page and Rautiainen study which showed subliminal stimulation enhanced real Maths proficiency (1992). It now appeared that Placebo wasn’t the only kid on the block.

Enter the most critically acclaimed series of subliminal messaging experiments, loosely referred to as the ‘symbiotic/oneness fantasies’, they showed subliminal suggestions in action. What was impressive about these studies is they showed change occurring at a very deep level. This line of research demonstrated that indirect subliminal messaging can reduce anxiety levels (Talbot, Duberstein & Scott, 1991; Malik, Krasney, Aldworth & Ladd, 1996). This built on previous research concerning the potential for the treatment for smoking cessation (Palmatier & Bornstein, 1980) and Schizophrenia (Kaplan, Thornton & Silverman, 1985).

These studies, and others like them, were surely impressive but they could not explain that (once the Placebo Effect is accounted for) subliminal messaging was associated with the desired result. They could only show that it worked, but they should not show how. What was required was convincing evidence that there was truly a clear divide between the conscious and unconscious and that it was this which was exploited by subliminal messaging.

Without the ‘how’ they lacked the full picture to end debate with any credibility.

Receiving Subliminal Stimuli

By this time, it already demonstrated that human senses acknowledged and were able to relay subliminal stimuli to the brain (that is the senses could pick up and send some form of signal to the brain). Physiological responses had been explored by Borgeat, Elie, Chaloult and Chabot (1985) who monitored changes in frontal EMG, skin conductance and heart rate. 

In 1996, Harris, Salus, Rerecich and Larsen demonstrated that it is possible to be consciously aware of subliminal messages without being able to consciously identify the message content. This was an important step which put subliminal self-help back on the map. Subliminal self-help requires that the critical conscious mind is bypassed (and the message not consciously identified) before the creative unconscious can accept suggestions. Should this be the case, the conscious mind could filter out the new ideas.

So at this stage researchers were assured that messages can be received by the brain, if only as signals devoid of interpretation.

Scans showing MRI of brainsResearch really needed to know whether message content was hitting the mark and producing the desired neurological responses. This would explain how the improvement was being created. That is, messages needed to influence the parts of the brain where meaningful information is processed at an unconscious level. With subliminal researchers’ access to MRI, research took a huge leap forward. The amazing link between the reception of the stimuli and the measurable influence on the intended area of the brain flickered on screen, (Kouider Dehaene, Jobert & Le Bihan, 2007; Dupoux, de Gardelle & Kouider, 2008). Oh, happy days.

This research proved that the messages received subliminally were sent to the appropriate part of the brain. With credit to MRI, it was ‘so far so good’ for the case of subliminal self-help messaging but there were still missing pieces to the argument. It was still not known how meaningful this was.

Interpreting and the Unconscious Perception of Information

The next step would be to determine what this unconscious influence could be. Is it akin to unconscious thought? The debate here, to some, is yet to be fully explored. What was clear from these studies is that some form of information is processed in the brain, but it is not readily apparent whether this process is semantic in nature.

That is, from MRI studies we were unable to say whether the words used in messages, were interpreted and processed as language in the brain.

To date, the most reasonable argument was evidenced by Van den Bussche, Notebaert & Reynvoet (2009) who concluded that the mode of thought depended upon the context of the messages used. In this study, the nature of the processing (semantic versus something else) was also linked to the type of influence the messages had upon desired effect. The following year, Davis, Kim & Barbaro (2010), strengthened the case for semantic processing. Their study demonstrated that the words which are selected for the message have significant impact. From these studies, it is reasonable to argue that subliminal messages are processed as words once they have reached the unconscious mind. The outcome of this debate is not absolutely critical for the case of subliminal messaging.

To date, it was shown that subliminal messages are received and are processed in the brain. It was still not properly demonstrated that these thoughts had influence on the individual. Alas, one final cornerstone of this research was missing. It came only very recently.

Psychological Traction

The most convincing evidence that subliminal messages impacts the relevant psychological processes came in 2012. Studies in May and June 2012 demonstrated that messages interacted with psychological constructs (in this case anxiety levels) and that some form of relationship existed, (Paul, Pope, Fennell & Mendl, 2012; Bustin, Quoidbach, Hansenne & Capa, 2012). The latter is still awaiting peer review.

Our True Human Potential

Science once again has caught up with human intuition (which ironically is the forte of the unconscious). Speculations of the great thinkers throughout the generations have been ratified by new technology. Messages can indeed be relayed to the subconscious mind, received, and (in all likelihood) semantically processed and influence our conscious attitudes and behaviour. Subliminal MP3s have been popular for a long time, despite the lack of empirical evidence to explain how they work. The research is starting to teach us how it is best used, what it can and cannot achieve.

For some this is a brand new world of possibility.  For some great thinkers and their adoring public (the author among them), a huge and welcome vindication.



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