London-Neuroscience is a fast growing and popular field, but despite advances, when an area of the brain ‘lights up” it does not tell us as much as we’d like about the inner workings of the mind.

Many of us have seen the pictures and read the stories. A beautiful picture of the brain where an area is highlighted and found to be fundamental for processes like fear, disgust or impaired social ability.

There are so many stories it can be easy to be swayed into thinking that much more of the brain’s mystery has been solved than is the case.

The technology is impressive but one of the most popular scanning methods - functional magnetic resonance imaging (fMRI) actually measures regional regional changes of blood flow to areas of the brain, not our neurons directly.

Researchers use it when they want to understand what part of the brain is involved in a particular task. They can place a person in a brain scanner and see which areas become active.

The areas that light up are then inferred to be important for that task, but the resulting images and phrase “lighting up the brain” can lead to over interpretation.

Neuroscientist Molly Crockett from University College London explains that while fMRI is extremely useful, we are still very far from being able to read an individual’s mind from a scan.

“There’s a misconception that’s still rather common that you can look at someone’s brain imaging data and be able to read off what they’re thinking and feeling. This is certainly not the case,” Dr Crockett told the BBC’s Inside Science programme. “A study will have been done which tells us something about the brain, but what [the public] really want to do is make the leap and understand the mind.”

She cites an article with the headline, “You love your iPhone, literally”. In this case a team saw an area previously associated with love - the insula - was active when participants watched videos of a ringing iPhone. But this area also been cited as the brain’s hate circuit, likened with disgust and as the brain’s addiction centre.

New blood ‘recharges old brain’


London-Researchers in the US say they might have discovered how to combat and even reverse some effects of ageing, at least in mice.

Injecting the blood of young mice into older rodents boosted their brainpower, a study found.

The scientists now want to carry out trials in people in the hope that new treatments for dementia can be developed. A UK dementia research charity said the human significance was unknown. In the study, published in Nature Medicine, mice aged 18 months were given transfusions of the fluid part of blood (plasma) from mice aged three months.

The treated mice performed better on memory tests than mice of the same age that had not been treated. “There are factors present in blood from young mice that can recharge an old mouse’s brain so that it functions more like a younger one,” said Dr Tony Wyss-Coray of Stanford University School of Medicine. “We’re working intensively to find out what those factors might be and from exactly which tissues they originate.” He said it was not known whether the same was true in humans, but a clinical trial was planned. Alzheimer’s Research UK said the treatment rejuvenated certain aspects of learning and memory in mice, but was “of unknown significance to humans”.