Flag waving is a metaphor for stirring up the public towards adopting a more nationalistic, generally hard-line stance. Indeed, "rally 'round the flag" is a venerable expression of this phenomenon.

It comes as some surprise, then, that studies conducted by researchers at the Hebrew University of Jerusalem have shown that exposing people to a subliminal image of the national flag had just the opposite fact -- moderating their political attitudes.

Further, the researchers say that their studies indicate that, in general, subliminal messages -- that is, messages that are processed by our brains but never reach our consciousness -- do indeed influence explicit attitudes and real-life political behavior, a significant extension to what we know about the effects of non-conscious processes.

The studies, led by cognitive scientist Dr. Ran Hassin of the Hebrew University of Jerusalem Psychology Department, show that the subliminal presentation of a national symbol affects not only political attitudes, but also voting intentions and actual voting in general elections.

In an article in the journal Proceedings of the National Academy of Sciences, a team led by Hassin reported on a set of experiments that examined the effects of the subliminal presentation of the national flag. The experiments involved over 300 participants who were recruited on the Mount Scopus campus of the Hebrew University.

In the first experiment, the Israeli participants, divided into two groups at random, were asked about their attitudes towards core issues in the Israeli-Palestinian conflict. Prior to answering these questions, half of them were exposed to subliminal images of the Israeli flag projected on a monitor and half of them were not. The results show that the former group tended to shift to the political center.

In other words, a brief presentation of the Israeli flag -- so brief, that people didn't even notice it -- was sufficient to make people adopt more moderate views. Another experiment, that was conducted in the weeks that preceded the Israeli pullout from Gaza, replicated these results and reflected centrist views in relation to the withdrawal and Jewish settlers in the West Bank and Gaza.

The third experiment was held just prior to Israel's last general elections. The results were identical. The subliminal presentation of Israel's flag drew right wing, as well as left wing, Israelis towards the political center. Crucially, participants who were subliminally exposed to the flag said they intended to vote for more central parties than those who had not been exposed to the subliminal message. The researchers then called the participants after the elections, and found out that people who were exposed to the flag indeed voted in a more moderate way.

Why this exposure to a national symbol should have what appears to be a surprising moderating effect remains yet to be studied and analyzed.

"I think these results are interesting for two reasons," says Hassin. "First, they provide sound empirical evidence for the non-conscious ways in which national ideologies subtly affect our thoughts and behaviors. We are now extending this research to examine what other ideologies can do so and in what ways this is expressed. "

"Secondly," he continued, "these results significantly extend the empirical knowledge regarding the nature and influences of unconscious processes. We are now investigating the mental mechanisms that underlie this phenomenon, and I am confident that this journey will yield new insights to our understanding of the cognitive unconscious -- and hence, of consciousness itself."