A woman fights back tears as she views flowers and mementoes left at a makeshift memorial outside the New York Fire Department's 48th Street firehouse two days after the Sept. 11 attacks. ((Ed Bailey/Associated Press))

Though Sept. 11 attacks on the U.S. remains forever etched in the memories of many North Americans, the intensity has inevitably faded with time.

But a recent study by a trio of German researchers brings back into sharp focus the emotions raging throughout that day, as the Twin Towers collapsed in New York, the Pentagon was struck and politicians reacted to the catastrophic chain of events.

Text messages from each emotion category



Guys we have cancelled our flight as you can expect. We are due to fly out @ 10:30 tomorrow, hopefully. Please let Joyce know, and call us or page us (if you can) on the cell. Kill the bastards! Jim


A lot of people were freaking out in the building. It was just terrible. Now is the time to strike back at these bastards.  rich


Amorcito, this is so shocking, I cannot believe this tragedy! Whatever you do...please be very careful, I know you might not be coming. I think I know where you are. I'm deeply sad, I imagine how you feel.

Clearly, no one should be in the vicinity of the downtown area or O'Hare under any circumstances. Work in the suburbs or work from home. Stop and a say a prayer for those that needlessly lost their loved ones.


Call me. I'm freaked out. Explosion prob. Plane hit Pentagon.  White House evacuated. Roads to DC closed.

The comparison to the Pearl Harbor attack is frightening. Too many angry people want to punch back and don't know where to strike. This will get uglier  :-0-cb

Interrupting u have u heard the shit thats goin down im really scared and i wish u were Love you always Richard

Three Mainz University professors — Albert Kuefner, Mitja Back and Boris Egloff — used a WikiLeaks-released document of pager messages from Sept. 11 to detail a timeline of the emotions (anger, sadness and anxiety) expressed in texts throughout the day.

"I think we can get some sort of idea or hint at least of what was going on in the States that day, all that anguish and wanting to seek revenge," said Kuefner.

The German team used a portion of the 24-hours' worth of pager messages, from 6:45 a.m. to 12:44 a.m., a period that encompasses two hours prior to and 18 hours after the first attack at 8:45 a.m.

A total of 6.4 million words from more than 85,000 distinguishable pager messages were analyzed by a well-known text analysis software program, checking for words related to anxiety (worried, fearful), sadness (crying, grief) and anger (hate, annoyed).

What they found surprised the scientists. "We expected a massive sad reaction to the tragedy … which wasn't the case at all. It pretty much stayed baseline," said Kuefner.

The striking discovery was instead the steady rise of anger throughout the day and into the night. Anger was present as soon as the first plane crashed and strengthened throughout the day, rising to 10 times the original amount by the end.

A temporary pause in the rising anger happened shortly after then-president George W. Bush's two speeches at 1:04 and 8:30 p.m., according to the study published in the Psychological Science journal.

Researchers believe Bush's impassioned speech helped to alleviate individual feelings of anger by serving as a collective outlet.

The biggest pause in rising anger occurs following Bush's first speech, when he told Americans that "the United States will hunt down and punish those responsible for these cowardly acts." It begins to climb again after 2:49 p.m. when New York Mayor Giuliani refuses to speculate about body count, saying it is "more than any of us can bear."

Anxiety peaked throughout the day, with the largest increase after the World Trade Center's south tower collapsed at 10:05 a.m. and the fourth plane crashed in Pennsylvania at 10:10 a.m. It's nearly as high after American Airlines reports the loss of two planes at 11:18 and United Airlines reports the Pennsylvania crash at 11:26 a.m.

As more information was released by the media, the anxiety reaction appears to drop. "We kind of interpret this as if you are unsure … you're really frightened. When you have information — a lot of people talking — then you're getting more secure. The anxiety reaction lessens," says Kuefner.

In the end, the analysis doesn't have an immediate practical application, admits Kuefner.

The professors suggest it may contribute to refining theories of emotion generation, coping in tragedy and making sense after a tragedy. At the very least, it provides an illuminating behind-the-scenes look at a traumatic day.

Delving into such personal messages — never intended to be made public — was a bit disquieting, Kuefner admits.

"It was a reminder of that day. It was nine years ago. I was a little surprised how much from your personal feeling, how much time was between attacks and now," said Kuefner. "You have very personal messages within the texts and you kind of get some sort of close feeling to those people.

"There were a lot of people texting that really loved somebody or who were afraid that they lost somebody. I felt closer to them that day."


The timeline of sadness, anxiety and anger on Sept. 11 as expressed in pager messages. Each data point represents the mean percentage of words related to the specific emotion, averaged across 30 minutes.