NEW YORK (WABC) -- Security in Times Square and other locations around New York City has been increased in the wake of the Paris terror attacks, and the NYPD assures residents and visitors that the city is safe. But the latest ISIS propaganda video is still making people nervous.
Mental health experts say the visible signs -- the extra officers on patrol and others who are specially trained -- may ease concerns, but the psychological toll traumatic events can take is too much for some to handle.
"Your worst nightmare, in terms of marrying terrorism with cyberspace and preying on people's vulnerability," Columbia University's Department of Psychiatry chairman Dr. Jeffrey Lieberman said. "And it's very effective."
And even though the material in the video is not new, Dr. Lieberman says the timing of its re-release, right after the vicious attacks on Paris, couldn't be worse.
"Pointing to Times Square during the holidays, Thanksgiving, Christmas, I mean you couldn't get something that was more effectively concocted than that," he said.
So to allay those fears, the NYPD has ramped up security measures, including its new Critical Response Command, consisting of more than 500 officers highly trained and heavily armed, who will go directly at terrorists. Police Commissioner William Bratton has seen the video.
"There is nothing specific on that video that's raising additional concerns on our part at this juncture," he said.
Still, others seek to calm concerns, as Hillary Clinton addressed it during her appearance on "Live with Kelly and Michael."
"The threat of attacks should be taken seriously, but people shouldn't take them personally," she said. "They should keep living their daily lives."
While there are no specific threats to the city, some people nevertheless will be disturbed by the video, experts say, and may harbor uneasy feelings that could manifest themselves in different ways.
"Make them have difficulty sleeping, stress them out," Dr. Lieberman said. "Adding to their usual level of stress dealing with their life during the day."
Terror threat, propaganda videos can take psychological toll, experts say
PARIS TERROR ATTACK