Inattentional Deafness: How Our Focus Can Silence The Noisy World Around Us

How can someone with perfectly normal hearing become deaf to the world around them when their mind is on something else? New research funded by the Wellcome Trust suggests that focusing heavily on a task results in the experience of deafness to perfectly audible sounds.

In a study published in the journal Attention, Perception, & Psychophysics, researchers at UCL (University College London) demonstrate for the first time this phenomenon, which they term 'inattentional deafness'.

"Inattentional deafness is a common everyday experience," explains Professor Nilli Lavie from the Institute of Cognitive Neuroscience at UCL. "For example, when engrossed in a good book or even a captivating newspaper article we may fail to hear the train driver's announcement and miss our stop, or if we're texting whilst walking, we may fail to hear a car approaching and attempt to cross the road without looking."

Professor Lavie and her PhD student James Macdonald devised a series of experiments designed to test for inattentional deafness. In these experiments, over a hundred participants performed tasks on a computer involving a series of cross shapes. Some tasks were easy, asking the participants to distinguish a clear colour difference between the cross arms. Others were much more difficult, involving distinguishing subtle length differences between the cross arms.

Participants wore headphones whilst carrying out the tasks and were told these were to aid their concentration. At some point during task performance a tone was played unexpectedly through the headphones. At this point, immediately after the sound was played, the experiment was stopped and the participants asked if they had heard this sound.

When judging the respective colours of the arms - an easy task that takes relatively little concentration - around two in ten participants missed the tone. However, when focusing on the more difficult task - identifying which of the two arms was the longest - eight out of ten participants failed to notice the tone.

The researchers believe this deafness when attention is fully taken by a purely visual task is the result of our senses of seeing and hearing sharing a limited processing capacity. It is already known that people similarly experience 'inattentional blindness' when engrossed in a task that takes up all of their attentional capacity - for example, the famous Invisible Gorilla Test, where observers engrossed in a basketball game fail to observe a man in a gorilla suit walk past. The new research now shows that being engrossed in a difficult task makes us blind and deaf to other sources of information.

"Hearing is often thought to have evolved as an early warning system that does not depend on attention, yet our work shows that if our attention is taken elsewhere, we can be effectively deaf to the world around us," explains Professor Lavie. "In our task, most people noticed the sound if the task being performed was easy and did not demand their full concentration. However, when the task was harder they experienced deafness to the very same sound."

Other examples or real world situations include inattentional deafness whilst driving. It is well documented that a large number of accidents are caused by a driver's inattention and this new research suggests inattentional deafness is yet another contributing factor. For example, although emergency vehicle sirens are designed to be too loud to ignore, other sounds - such as a lorry beeping while reversing, a cyclist's bell or a scooter horn - may be missed by a driver focusing intently on some interesting visual information such as a roadside billboard, the advert content on the back of the bus in front or the map on a sat nav.

Source:
Craig Brierley
Wellcome Trust

Experts Would Like Specialized Teaching For Dyscalculia Introduced In Schools

Specialised teaching for individuals with dyscalculia, the mathematical equivalent of dyslexia, should be made widely available in mainstream education, according to a review of current research published in the journal Science.

Although just as common as dyslexia, with an estimated prevalence of up to 7% of the population, dyscalculia has been neglected as a disorder of cognitive development. However, a world-wide effort by scientists and educators has established the essential neural network that supports arithmetic, and revealed abnormalities in this network in the brains of dyscalulic learners.

Neuroscience research shows what kind of help is most needed - strengthening simple number concepts. This can be achieved with appropriate specially-designed teaching schemes, which can be supported by game-like software that adapts to the learner's current level of competence.

Professor Brian Butterworth, co-author of the paper and a member of the Centre for Educational Neuroscience (CEN) from the UCL Institute of Cognitive Neuroscience, said: "Dyscalculia is at least as much of a handicap for individuals as dyslexia and a very heavy burden on the state, with the estimated cost to the UK of low numeracy standing at £2.4 billion."

"Nevertheless, there are only cursory references to the disorder on the Department of Education website - no indications are offered for help either for learners, teachers or parents. It's as if the government does not want to acknowledge its existence."

Like dyslexia, dyscalculia is a condition we are born with, and may be heritable in many or most cases. Research from twins and special populations suggests that an arithmetical disability has a large genetic component, but the genes responsible have not yet been located.

Professor Diana Laurillard, another co-author and a member of CEN from the Institute of Education (IOE), University of London, said: "Just because dyscalculia is inherited it does not mean that there is nothing that can be done about it. As with dyslexia, specialized teaching can help. At the IOE we have developed software resources specifically to help children with dyscalculia, based on brain research showing exactly what problems the brain is having."

One of the main challenges of the effort to understand dyscalculia, is for scientists from these very different disciplines to understand each others' methods and results. The creation of interdisciplinary and inter-institutional centres to promote joint work, such as the Centre for Educational Neuroscience established by UCL (University College London); the Institute of Education, University of London and Birkbeck University of London, aims to address this challenge.

Professor Laurillard added: "Results from neuroscience and developmental psychology tell us that dyscalculic learners need to practice far more number manipulation tasks than mainstream learners. Adaptive, game-like programs that focus on making numbers meaningful, emulating what skilled SEN teachers do, can help learners practice beyond the classroom and build the basic understanding they need to tackle arithmetic."

What is dyscalculia?

Examples of common indicators of dyscalculia are (i) carrying out simple number comparison and addition tasks by counting, often using fingers, well beyond the age when it is normal, and (ii) finding approximate estimation tasks difficult. Individuals identified as dyscalculic behave differently from their mainstream peers, for example: To say which is the larger of two playing cards showing 5 and 8, they count all the symbols on each card. To place a playing card of 8 in sequence between a 3 and a 9 they count up spaces between the two to identify where the 8 should be placed. To count down from 10 they count up from 1 to 10, then 1 to 9, etc. To count up from 70 in tens, they say '70, 80, 90, 100, 200, 300...' They estimate the height of a normal room as '200 feet?' Source:
Clare Ryan
University College London

Sleep On It Is Sound, Science Based Advice

In recent years, much sleep research has focused on memory, but now results of a new study by University of Massachusetts Amherst psychologist Rebecca Spencer and colleagues suggest another key effect of sleep is facilitating and enhancing complex cognitive skills such as decision-making.

In one of the first studies of its kind, Spencer and postdoctoral fellow Edward Pace-Schott investigated the effects of sleep on affect-guided decision-making, that is decisions on meaningful topics where subjects care about the outcome, in a group of 54 young adults. They were taught to play a card game for rewards of play money in which wins and losses for various card decks mimic casino gambling.

Subjects who had a normal night's sleep as part of the study drew from decks that gave them the greatest winnings four times more often than those who spent the 12-hour break awake, and they better understood the underlying rules of the game. Psychologists believe rule discovery is an often hidden yet key factor that is crucial to making sound decisions.

"This provides support for what Mom and Dad have always advised," says Spencer. "There is something to be gained from taking a night to sleep on it when you're facing an important decision. We found that the fact that you slept makes your decisions better."

This role of sleep in everyday life is accepted as common wisdom, but it hasn't been well characterized by science until now, she adds. She and her colleagues believe this sleep benefit in making decisions may be due to changes in underlying emotional or cognitive processes. "Our guess is that this enhanced effect on decision-making is something that depends on rapid-eye-movement or REM sleep, which is the creative period of our sleep cycle," the psychologist notes. Results are in the current early online issue of the Journal of Sleep Research.

The UMass Amherst study used the Iowa Gambling Task, a gambling card game that assesses frontal lobe function, where more emotional decisions originate. Spencer explains, "It means that you care about the wins and losses. You care about winning."

To begin, the researchers gave two groups of 18- to 23-year-old college undergraduates a brief morning or afternoon preview of the gambling task, so brief that it was not possible for them to learn its underlying rule. Subjects were then asked to come back in 12 hours. The 28 subjects who got the preview in the afternoon went home to a normal evening and their usual night of sleep while the 26 who received the game preview in the morning came back after a day of normal activities with no naps.

On the second visit, subjects played the full gambling task for long enough to learn that drawing cards from four decks of cards yielded different rewards of play money: Drawing from two advantageous decks yielded low rewards, occasional low losses and a net gain over many draws, while drawing from disadvantageous decks yielded high rewards, occasional high losses and a net loss over many draws. The object was to avoid losing and collect as much play money as possible.

Subjects who got to sleep between the game's brief introduction and the longer play session showed both superior behavioral outcome, that is, more advantageous draws, and superior rule understanding when asked to explain them at the end, than those who did not sleep between sessions.

To assure that time of day didn't explain the different performance between sleep and wake groups, the researchers added two smaller groups of 17 and 21 subjects to perform both the preview and the full task either in the morning or the evening. All subjects said they had normal sleep patterns (for college students) and the groups didn't differ on overall game skills at the start. Males and females do not differ in game-playing skills, the authors point out, but there were equal numbers in each group.

Source: University of Massachusetts Amherst