Brain emits early signal on attention lapses

Trinity College Dublin scientists have discovered a way to predict when a person's lapse in attention is going to cause an error, writes DICK AHLSTROM.

WE ALL MAKE mistakes, but now researchers have found a way to predict when you are about to make one – a full 20 seconds ahead of time.

The discovery at Trinity College Dublin’s School of Psychology and Institute of Neuroscience immediately offers the possibility of developing an early warning system that can watch for lapses in attention, say in long distance truck drivers. The finding may also point to new highly sensitive methods for detecting the onset of neurological problems such as Alzheimer’s disease, suggests lead researcher and professor of psychology Ian Robertson.

He and Dr Redmond O’Connell collaborated with a group from the Nathan S Kline Institute for Psychiatric Research in New York in a study published last month in the Journal of Neuroscience.

The research sought to examine in very precise detail processes in the brain related to our ability to pay attention. “Attention with memory is one of the most important human faculties,” Robertson suggests.

It is disrupted in conditions such as dementia, attention disorders and with emotional disturbances and so lies at the heart of these conditions. He describes attention as “the ability to select certain information relevant to everyday activities”; in effect, keeping focused on what is important and ignoring distractions.

“An awful lot of accidents are caused by people not selecting the right information or not focusing on the right things,” says Robertson.

Being able to maintain focus is an essential part of modern living, but doing so in the face of a tedious task, such as long-haul driving or flying an aircraft, runs counter to the way our brains are programmed to work.

“The human brain is an organ that loves variety, that likes new things,” Robertson says.

Researchers began looking at attention more closely after the introduction of radar. Operators found it difficult to maintain their focus on a screen that seldom changed, leading to an increased risk of errors. “This research was an attempt to explore exactly what happens in the brain when attention wanders,” he explains.

Redmond O’Connell was first author on the project, which involved getting 21 subjects to undergo a screen-based test of concentration while monitoring their background brain activity using an electroencephalogram. The EEG uses electrodes placed on the scalp to detect tiny electrical signals given off by the brain while active and at rest.

This provided two streams of information that were synchronised, one the EEG read-out and another which tracked the person’s interaction with the computer screen.

The test was very simple, but demanded constant attention to avoid errors, O’Connell says. Subjects watched changing checkerboard patterns and were asked to push a button when they saw a pattern that remained on the screen slightly longer than the others. The patterns were not important, it was the time they stayed on the screen, he says.

Subjects took a series of 10 three-minute tests. “When you do the task you really do feel like you have been a boxing ring,” he says.

Once completed, the test results were averaged and then compared to what the EEG was showing. The team was startled to see that the EEG, when recording a brain signal based on production of something called alpha waves, could show in advance when the subject was losing focus and about to make a mistake.

“Our results show that the specific neural signatures of attentional lapses are registered in the EEG up to 20 seconds before an error,” the authors write in their research paper.

This has immediate implications for accident avoidance and safety, O’Connell believes. “This tells us it is possible to predict a loss of attention.” It should be feasible to develop a device that could monitor for this and emit a warning signal.

“It might also provide a more accurate marker for gradual neurological decline,” Robertson adds. “It would provide a very sensitive marker for a very important brain function.” It might give a much earlier warning of advancing dementia long before symptoms begin to arise.