What did your school smell like? Was it noisy or peaceful?
It might not seem important, but a growing body of research suggests that smells and sounds can have an impact on learning, performance and creativity. Indeed, some head teachers have recently taken to broadcasting noises and pumping whiffs into their schools to see whether it can boost grades. Is there anything in it? And if so, what are the implications for the way we all work and study?
There is certainly some well-established research to suggest that some noises can have a detrimental effect on learning. Numerous studies over the past 15 years have found that children attending schools under the flight paths of large airports lag behind in their exam results.
But general noise seems to have an effect too. Bridget Shield, a professor of acoustics at London South Bank University, and Julie Dockrell, now at the Institute of Education, have been conducting studies and advising politicians on the effects of all sorts of noises, such as traffic and sirens, as well as noise generated by the children themselves. When they recreated those particular sounds in an experimental setting whilst children completed various cognitive tasks, they found a significant negative effect on exam scores. “Everything points to a detrimental impact of the noise on children’s performance, in numeracy, in literacy, and in spelling,” says Shield. The noise seemed to have an especially detrimental effect on children with special needs. `
Shield says the sound of “babble” – the chatter of other children, is particularly distracting in the classroom. Architects that fashion open-plan classrooms in schools would do well to take this on board. “People are very distracted by speech – particularly if it’s understandable, but you’re not involved in it.” This phenomenon is also known as the irrelevant speech effect, she says, adding that “it’s a very common finding in open-plan offices as well.”
Whether background sounds are beneficial or not seems to depend on what kind of noise it is – and the volume. In a series of studies published last year, Ravi Mehta from the College of Business at Illinois and colleagues tested people’s creativity while exposed to a soundtrack made up of background noises – such as coffee-shop chatter and construction-site drilling – at different volumes. They found that people were more creative when the background noises were played at a medium level than when volume was low. Loud background noise, however, damaged their creativity.
This makes sense for a couple of reasons, says psychologist Dr Nick Perham, at Cardiff Metropolitan University in the UK, who studies the effect of sounds on learning but was not involved in the study. Firstly, he says, sounds that are most distracting tend to be very variable. A general hum in the background suggests a steady-state sound with not much acoustical variation. “So there’s not much there to capture your attention – nothing distracting the subjects,” he says. At the same time, the background noise might cause the subjects to be in a slightly heightened state of arousal, says Perham. You don’t want too much or too little arousal. “Medium arousal is best for good performance. So it might be that a general hum in the background gives an optimum level of arousal.” With that in mind, Perham suggests there may be some benefit to playing music or other sounds in an art class or other situations where creativity is key.
Many teachers all over the world already play music to students in class. Many are inspired by the belief that hearing music can boost IQ in subsequent tasks, the so-called Mozart effect. While the evidence actually suggests it’s a stretch to say classical music boosts brainpower, researchers do think pleasant sounds before a task can sometimes lift your mood and help you perform well, says Perham, who has done his own studies on the phenomenon. The key appears to be that you enjoy what you’re hearing. “If you like the music or you like the sound – even listening to a Stephen King novel – then you did better. It didn’t matter about the music,” he says.
However, it’s worth considering that music is not always helpful while you’re trying to work. Trying to perform a task which involves serial recall – for instance, doing mental arithmetic – will be impaired by sounds with acoustic variation, which includes most types of music, says Perham. (Except a few, like extreme death metal.) Songs with lyrics, on the other hand, are more likely to interfere with tasks that involve semantics – such as reading comprehension. “The task and the sound are important, when you have both of them using the same process then you get problems,” he says.
So, it seems that schools that choose to screen out disturbing noises and create positive soundscapes could enhance the learning of their students, so long as they make careful choices.
This isn’t the only sense being tweaked to affect learning. Special educational needs students at Sydenham high school in London are being encouraged to revise different subjects in the presence of different smells – grapefruit scents for maths, lavender for French and spearmint for history.
Less research has gone into the idea of whether scents can help with cognitive performance, although there have been intriguing findings. In 2003, psychologist Mark Moss, at Northumbria University, carried out a range of cognitive tests on subjects who were exposed either to lavender or rosemary aromas. “Rosemary in particular caught my attention as it is considered to be arousing and linked to memory,” he says, whereas lavender is considered to be sedating. Moss found that those who were smelling lavender performed significantly worse in working memory tests, and had impaired reaction times for both memory and attention-based tasks, compared to controls. Those in the rosemary group, on the other hand, did much better than controls overall in the memory tasks, although their reaction times were slower.
Why might this be? It’s perhaps not surprising that smells affect memory, given that the brain’s olfactory bulb is intimately linked to the hippocampus, which deals with learning. But Moss suspected there was more to it. To explore the pharmacological effects of rosemary on the body, he drew blood samples from volunteers who had just undergone cognitive tests in a rosemary-infused room, and found that they had elevated levels of a compound called 1,8-cineole in their blood. Previous research has shown that this compound increases communication between brain cells, which might explain how it improves brain function.
So, as you finish reading this story, take a moment to tune into your senses. Close your eyes and take a few nice deep breaths. What can you hear and smell? The answer, it seems, may affect how much you learnt in the past few minutes.