In terms of reducing both overall and physical aggression, clozapine was significantly better than olanzapine, which, in turn, was significantly better than haloperidol. By contrast, the agents were comparable in their ability to improve psychiatric symptoms.
"Clozapine was better than the other drugs at reducing physical assaults, threats, and insults and in preventing patients from destroying property and throwing objects," Krakowski said.
While clozapine is the most effective drug, Krakowski warned that the drug also has some important side effects and regular blood monitoring is critical. For this reason, olanzapine might be a better initial choice, he added, unless the patient has hard-to-control aggressive behavior.
SOURCE: Archives of General Psychiatry,
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Fact is, without the help of color, the human brain can't pay attention to more than three moving objects at once, concluded a team of neurological researchers reporting in the July issue of Psychological Science.
Grouping even a vast number of objects or people together by color makes all the difference, the researchers said.
"That's a new finding -- that humans can attend to more than three items if those items form a single set," said study co-researcher Justin Halberda, an assistant professor of psychological and brain sciences at Johns Hopkins University. "The set itself can then function as an individual," he added.
According to Halberda, a variety of tests have proven over and over that humans of all ages, as well as other primates, can't keep their attention fixed on more than three items at once in a given visual field. "We've never seen a case where that wasn't true," he said.
So, that finding begged the question: How can humans follow and enjoy team sports, which often contain dozens of players running in various directions at once? Halberda and his colleagues suspected the answer lay in the fact that societies have historically clothed opposing teams -- even opposing soldiers -- in different colors.
"Color is processed very early [by the brain]," Halberda said, so it makes sense that it would function as a nearly immediate cue to who belongs to what.
In their study, the Hopkins scientists had undergraduate volunteers view a series of colored dots that flashed before their eyes on a computer screen for just a half-second -- too short a time for counting.
The dots were arranged randomly, but some shared a color -- say, red or green. The researchers would sometimes warn the volunteers ahead of time to "watch for the red dots," for example. But in other experiments, the volunteers were given no such warning and were simply told to pay attention to the screen.
The researchers then asked the participants to recall how many dots of a specific color they thought they had seen.
The result: Participants did well at estimating the number of dots when told in advance which colors they should pay attention to, demonstrating they could pay attention to large numbers of items based on color alone. In fact, participants were accurate in estimating the number of color-specific dots even when the total collection consisted of a wide spectrum of colors.
Participants did less well when they weren't told beforehand which color they should fix their attention on. They were still able to recall, with some accuracy, the number of dots of a certain color -- but only when the whole array was comprised of dots of three colors or less.
Translating these findings from the computer screen to the playing field isn't a great leap, Halberda said.
"If you consider something like the World Cup, you have this big green field, and you're not so much tracking the items as they move, in terms of color -- it's just seeing them all in the first place," Halberda said. "So, England's bright white jerseys jump out from the green background and that makes them easier to pay attention to."
But humans also have an upper limit when it comes to paying attention to sets, Halberda said, and it's the same as their tolerance for tracking individual objects -- three.
That could explain why, throughout history, people have stuck to games with just two opposing teams. "Our research suggests that if a game was devised with four teams playing simultaneously, it would just be too many for any spectator, coach or player to pay attention to," Halberda said.
