Posts Tagged ‘DAVID NIELD’



Why is it sometimes so hard to convince someone that the world is indeed a globe, or that climate change is actually caused by human activity, despite the overwhelming evidence?

Scientists think they might have the answer, and it’s less to do with lack of understanding, and more to do with the feedback they’re getting.

Getting positive or negative reactions to something you do or say is a greater influence on your thinking than logic and reasoning, the new research suggests – so if you’re in a group of like-minded people, that’s going to reinforce your thinking.

Receiving good feedback also encourages us to think we know more than we actually do.

In other words, the more sure we become that our current position is right, the less likely we are to take into account other opinions or even cold, hard scientific data.

“If you think you know a lot about something, even though you don’t, you’re less likely to be curious enough to explore the topic further, and will fail to learn how little you know,” says one of the team members behind the new study, Louis Marti from the University of California, Berkeley.

For the research, more than 500 participants were recruited and shown a series of colored shapes. As each shape appeared, the participants got asked if it was a “Daxxy” – a word made up for these experiments.

The test takers had no clues as to what a Daxxy was or wasn’t, but they did get feedback after guessing one way or the other – the system would tell them if the shape they were looking at qualified as a Daxxy or not. At the same time they were also asked how sure they were about what a Daxxy actually was.

In this way the researchers were able to measure certainty in relation to feedback. Results showed the confidence of the participants was largely based on the results of their last four or five guesses, not their performance overall.

You can see the researchers explain the experiment in the video below:

The team behind the tests says this plays into something we already know about learning – that for it to happen, learners need to recognise that there is a gap between what they currently know and what they could know. If they don’t think that gap is there, they won’t take on board new information.

“What we found interesting is that they could get the first 19 guesses in a row wrong, but if they got the last five right, they felt very confident,” says Marti. “It’s not that they weren’t paying attention, they were learning what a Daxxy was, but they weren’t using most of what they learned to inform their certainty.”

This recent feedback is having more of an effect than hard evidence, the experiments showed, and that might apply in a broader sense too. It could apply to learning something new or trying to differentiate between right and wrong.

And while in this case the study participants were trying to identify a made-up shape, the same cognitive processes could be at work when it comes to echo chambers on social media or on news channels – where views are constantly reinforced.

“If you use a crazy theory to make a correct prediction a couple of times, you can get stuck in that belief and may not be as interested in gathering more information,” says one of the team, psychologist Celeste Kidd from UC Berkeley.

So if you think vaccinations are harmful, for example, the new study suggests you might be basing that on the most recent feedback you’ve had on your views, rather than the overall evidence one way or the other.

Ideally, the researchers say, learning should be based on more considered observations over time – even if that’s not quite how the brain works sometimes.

“If your goal is to arrive at the truth, the strategy of using your most recent feedback, rather than all of the data you’ve accumulated, is not a great tactic,” says Marti.

The research has been published in Open Mind.



A specific part of the brain called the caudate nucleus could control pessimistic responses, according to animal tests, a finding which might help us unlock better treatments for mental disorders like anxiety and depression.

These disorders often come with negative moods triggered by a pessimistic reaction, and if scientists can figure out how to control that reaction, we might stand a better chance of dealing with the neuropsychiatric problems that affect millions of people worldwide – and maybe discover the difference between glass half full and glass half empty people along the way.

The research team from MIT found that when the caudate nucleus was artificially stimulated in macaques, the animals were more likely to make negative decisions, and consider the potential drawback of a decision rather than the potential benefit.

This pessimistic decision-making continued right through the day after the original stimulation, the researchers found.

“We feel we were seeing a proxy for anxiety, or depression, or some mix of the two,” says lead researcher Ann Graybiel. “These psychiatric problems are still so very difficult to treat for many individuals suffering from them.”

The caudate nucleus has previously been linked to emotional decision-making, and the scientists stimulated it with a small electrical current while the monkeys were offered a reward (juice) and an unpleasant experience (a puff of air to the face) at the same time.

In each run through the amount of juice and the strength of the air blast varied, and the animals could choose whether or not to accept the reward – essentially measuring their ability to weigh up the costs of an action against the benefits.

When the caudate nucleus was stimulated, this decision-making got skewed, so the macaques started rejecting juice/air ratios they would have previously accepted. The negative aspects apparently began to seem greater, while the the rewards became devalued.

“This state we’ve mimicked has an overestimation of cost relative to benefit,” says Graybiel. After a day or so, the effects gradually disappeared.

The researchers also found brainwave activity in the caudate nucleus, part of the basal ganglia, changed when decision-making patterns changed. This might give doctors a marker to indicate whether someone would be responsive to treatment targeting this part of the brain or not.

The next stage is to see whether the same effect can be noticed in human beings – scientists have previously linked abnormal brain activity in people with mood disorders to regions connected to the caudate nucleus, but there’s a lot more work to be done to confirm these neural connections.

Making progress isn’t easy because of the incredibly complexity of the brain, but the researchers think their results show the caudate nucleus could be disrupting dopamine activity in the brain, controlling mood and our sense of reward and pleasure.

“There must be many circuits involved,” says Gabriel. “But apparently we are so delicately balanced that just throwing the system off a little bit can rapidly change behaviour.”

The research has been published in Neuron.