Publishing in Nature Communications scientists from UCL explore the potential effects a satellite navigation system could have on the brain.
Dr Christopher Connolly, Reader in Neurobiology, University of Dundee, said:
“This is an interesting study into hippocampal function in navigation, where choices may be made using spatial mapping and relational memory. As expected, it is demonstrated that such mechanisms are not required if navigational decisions are made by satnav (or presumably by Mum, Dad or friend).
“We still need to navigate ourselves around other maps not covered by satnav, such as at work/school or when shopping. Furthermore, the hippocampus plays a critical role in the consolidation of short term memory to long term memory, a function that is lost during Alzheimer’s disease. Although previous studies have reported that brain training exercises improve the skills in that task, they do not necessarily improve our performance in other learning tasks.
“Rather than a highly dubious extrapolation (from the findings of this excellent study) to suggest a need to restrict our use of satnavs to less than 5 minutes per day, perhaps a more relevant, and positive, message would be to engage our brains and bodies in a variety of different tasks that promote our happiness and health.”
Dr Dean Burnett, Neuroscience and psychiatry lecturer, Cardiff Centre for Medical Education, Cardiff University, said:
“The study is interesting, but I feel the claims made (in the press release) are a bit misleading. Sat navs don’t ‘switch off’ parts of the brain, they just prevent increased activation of the hippocampus, which would normally be the result of people engaging in complex spatial navigation. But that ‘increased’ is important, as the hippocampus, a vital brain region for encoding long term memories, is always on, if it’s ‘switched off’ for even a few seconds lasting damage can occur, as stroke victims often find out.
“The study itself is relatively small but about usual for a scanning study of this nature, given the restrictions in terms of expense and timing and practicality (scanners are huge, costly things to run). This means any results from it shouldn’t be taken as definitive proof of any claims made, but the link between spatial navigation and the hippocampus is based on a large body of data now so it’s fairly consistent with current understanding.
“The theory that the hippocampus becomes more active in response to challenging spatial navigation demands being made on the brain is not exactly new, but I think this may be the first time it’s been demonstrated in ‘typical’ subject. Eleanor Maguire, who first demonstrated the London cabbies having bigger and more active hippocampi, did a follow up experiment comparing their brains to those of London bus drivers, who have very similar jobs, but only stick to pre-set routes and don’t have to work out directions and coordinates ‘on the fly’, so to speak. Bus driver brains were far more in-keeping with standard brain activity, so it’s the need to work out directions and navigation that causes this raised activity. Sat navs would also remove the need for the individual to do this, so seeing a similar result isn’t that surprising.
“Most people manage a normal existence without taxing their navigation skills very much, but the taxi driver data suggests the more you do it, the better you are at it as your brain develops to facilitate it in response. If you want to become better at spatial navigation, then you should avoid sat navs where possible. If you just want to get to your destination with as little worry or effort as possible, then they’re fine.”
* ‘Hippocampal and prefrontal processing of network topology to simulate the future’ by Javadi et al. will be published in Nature Communications on Tuesday 21st March.
Dr Connolly: None
Dr Burnett: None