The study zeroes in on a phenomenon known to anyone who’s ever had trouble doing the same task for a long time: After a while, you begin to lose your focus and your performance on the task declines.
Some researchers believe that this “vigilance decrement,” as they describe it, is the result of a drop in one’s “attentional resources,” said University of Illinois psychology professor Alejandro Lleras, who led the new study. “For 40 or 50 years, most papers published on the vigilance decrement treated attention as a limited resource that would get used up over time, and I believe that to be wrong. You start performing poorly on a task because you’ve stopped paying attention to it,” he said. “But you are always paying attention to something. Attention is not the problem.”
Lleras had noticed that a similar phenomenon occurs in sensory perception: The brain gradually stops registering a sight, sound or feeling if that stimulus remains constant over time. For example, most people are not aware of the sensation of clothing touching their skin. The body becomes “habituated” to the feeling and the stimulus no longer registers in any meaningful way in the brain.
In previous studies, Lleras explored the limits of visual perception over time, focusing on a phenomenon called Troxler Fading: when continual attention to a stationary object in one’s peripheral vision can lead to that object’s complete “disappearance” from view.
“Constant stimulation is registered by our brains as unimportant, to the point that the brain erases it from our awareness,” Lleras said. “So I thought, well, if there’s some kind of analogy about the ways the brain fundamentally processes information, things that are true for sensations ought to be true for thoughts. If sustained attention to a sensation makes that sensation vanish from our awareness, sustained attention to a thought should also lead to that thought’s disappearance from our mind!”
In the new study, Lleras and postdoctoral fellow Atsunori Ariga tested participants’ ability to focus on a repetitive computerized task for about an hour under various conditions. The 84 study subjects were divided into four groups:
• The control group performed the 50-minute task without breaks or diversions.
• The “switch” group and the “no-switch” group memorized four digits prior to performing the task, and were told to respond if they saw one of the digits on the screen during the task. Only the switch group was actually presented with the digits (twice) during the 50-minute experiment. Both groups were tested on their memory of the digits at the end of the task.
• The “digit-ignored” group was shown the same digits presented to the switch group during the task, but was told to ignore them.
As expected, most participants’ performance declined significantly over the course of the task. But most critically, Lleras said, those in the switch group saw no drop in their performance over time. Simply having them take two brief breaks from their main task (to respond to the digits) allowed them to stay focused during the entire experiment.
“It was amazing that performance seemed to be unimpaired by time, while for the other groups performance was so clearly dropping off,” he said.
This study is consistent with the idea that the brain is built to detect and respond to change, Lleras said, and suggests that prolonged attention to a single task actually hinders performance.
“We propose that deactivating and reactivating your goals allows you to stay focused,” he said. “From a practical standpoint, our research suggests that, when faced with long tasks (such as studying before a final exam or doing your taxes), it is best to impose brief breaks on yourself. Brief mental breaks will actually help you stay focused on your task!”
Lleras is a researcher at the university’s Beckman Institute for Advanced Science and Technology.
Diana Yates | University of Illinois
Europe’s Demographic Future. Where the Regions Are Heading after a Decade of Crises
10.08.2017 | Berlin-Institut für Bevölkerung und Entwicklung
Scientists reveal source of human heartbeat in 3-D
07.08.2017 | University of Manchester
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences