Neuroscientists literally change the way we think: Advantages of a wandering mind

Bar-Ilan University

Summary:

Does your mind wander when performing monotonous, repetitive tasks? Of course! But daydreaming involves more than just beating back boredom. In fact, according to a new study, a wandering mind can impart a distinct cognitive advantage.

Does your mind wander when performing monotonous, repetitive tasks? Of course! But daydreaming involves more than just beating back boredom. In fact, according to a new study published in the Proceedings of the National Academy of Sciences, a wandering mind can impart a distinct cognitive advantage.

Scientists at Bar-Ilan University are the first to demonstrate how an external stimulus of low-level electricity can literally change the way we think, producing a measurable up-tick in the rate at which daydreams -- or spontaneous, self-directed thoughts and associations -- occur. Along the way, they made another surprising discovery: that while daydreams offer a welcome "mental escape" from boring tasks, they also have a positive, simultaneous effect on task performance.

The new study was carried out in Bar-Ilan's Cognitive Neuroscience Laboratory supervised by Prof. Moshe Bar, part of the University's Gonda (Goldschmied) Multidisciplinary Brain Research Center which Prof. Bar also directs.

What Makes a Mind Wander?

While a far cry from the diabolical manipulation of dream content envisioned in "Inception" -- the science-fiction thriller starring Leonardo DiCaprio -- the Bar-Ilan University study is the first to prove that a generic external stimulus, unrelated to sensory perception, triggers a specific type of cognitive activity.

In the experiment -- designed and executed by Prof. Bar's post-doctoral researcher Dr. Vadim Axelrod -- participants were treated with transcranial direct current stimulation (tDCS), a non-invasive and painless procedure that uses low-level electricity to stimulate specific brain regions. During treatment, the participants were asked to track and respond to numerals flashed on a computer screen. They were also periodically asked to respond to an on-screen "thought probe" in which they reported -- on a scale of one to four -- the extent to which they were experiencing spontaneous thoughts unrelated to the numeric task they had been given.

The Brain-Daydream Connection

According to Prof. Bar -- a long-time faculty member at Harvard Medical School who has authored several studies exploring the link between associative thinking, memory and predictive ability -- the specific brain area targeted for stimulation in this study was anything but random.

"We focused tDCS stimulation on the frontal lobes because this brain region has been previously implicated in mind wandering, and also because is a central locus of the executive control network that allows us to organize and plan for the future," Bar explains, adding that he suspected that there might be a connection between the two.

As a point of comparison and in separate experiments, the researchers used tDCS to stimulate the occipital cortex -- the visual processing center in the back of the brain. They also conducted control studies where no tDCS was used.

While the self-reported incidence of mind wandering was unchanged in the case of occipital and sham stimulation, it rose considerably when this stimulation was applied to the frontal lobes. "Our results go beyond what was achieved in earlier, fMRI-based studies," Bar states. "They demonstrate that the frontal lobes play a causal role in the production of mind wandering behavior."

Improved "Cognitive Capacity" of the Wandering Mind

In an unanticipated finding, the present study demonstrated how the increased mind wandering behavior produced by external stimulation not only does not harm subjects' ability to succeed at an appointed task, it actually helps. Bar believes that this surprising result might stem from the convergence, within a single brain region, of both the "thought controlling" mechanisms of executive function and the "thought freeing" activity of spontaneous, self-directed daydreams.

"Over the last 15 or 20 years, scientists have shown that -- unlike the localized neural activity associated with specific tasks -- mind wandering involves the activation of a gigantic default network involving many parts of the brain," Bar says. "This cross-brain involvement may be involved in behavioral outcomes such as creativity and mood, and may also contribute to the ability to stay successfully on-task while the mind goes off on its merry mental way."

While it is commonly assumed that people have a finite cognitive capacity for paying attention, Bar says that the present study suggests that the truth may be more complicated.

"Interestingly, while our study's external stimulation increased the incidence of mind wandering, rather than reducing the subjects' ability to complete the task, it caused task performance to become slightly improved. The external stimulation actually enhanced the subjects' cognitive capacity."

Toward A Less-Mysterious Mind

Bar says that, in the future, he would be interested in studying how external stimulation might affect other cognitive behaviors, such as the ability to focus or perform multiple tasks in parallel. And while any therapeutic application of this technique is speculative at best, he believes that it might someday help neuroscientists understand the behavior of people suffering from low or abnormal neural activity.

In the meantime, Bar's team at the BIU Lab for Cognitive Neuroscience is pleased to note that in their work on mind wandering -- probably the most omnipresent internal cognitive function -- they have made the human brain just a little less mysterious

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Story Source:

The above story is based on materials provided by Bar-Ilan University. Note: Materials may be edited for content and length.

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Journal Reference:

1.         Vadim Axelrod, Geraint Rees, Michal Lavidor, Moshe Bar. Increasing propensity to mind-wander with transcranial direct current stimulation. Proceedings of the National Academy of Sciences, 2015; 201421435 DOI: 10.1073/pnas.1421435112

Keep calm, anger can trigger a heart attack

University of Sydney

The risk of a heart attack is 8.5 times higher in the two hours following a burst of intense anger, researchers have found after investigating the link between acute emotional triggers and high risk of severe cardiac episodes. High levels of anxiety were associated with a 9.5 fold increased risk of triggering a heart attack in the two hours after an anxiety episode.

University of Sydney research reveals that the risk of a heart attack is 8.5 times higher in the two hours following a burst of intense anger.

Published in European Heart Journal: Acute Cardiovascular Care, this is the first Australian study to investigate the link between acute emotional triggers and high risk of severe cardiac episodes.

"Our findings confirm what has been suggested in prior studies and anecdotal evidence, even in films -- that episodes of intense anger can act as a trigger for a heart attack," said lead author Dr Thomas Buckley, Sydney Nursing School, University of Sydney, and researcher at Royal North Shore Hospital.

"The data shows that the higher risk of a heart attack isn't necessarily just while you're angry -- it lasts for two hours after the outburst.

In the study, 'anger' was qualified as 5 and above on a 1-7 scale, referring to 'very angry, body tense, clenching fists or teeth, ready to burst', up to 'enraged, out of control, throwing objects'. Anger below this level was not associated with increased risk.

"The triggers for these burst of intense anger were associated with arguments with family members (29 per cent), argument with others (42 per cent), work anger (14 per cent) and driving anger (14 per cent)," said Dr Buckley.

"The data also revealed that episodes of anxiety can also make you more likely to have heart attack.

"High levels of anxiety were associated with a 9.5 fold increased risk of triggering a heart attack in the two hours after the anxiety episode.

"Increased risk following intense anger or anxiety is most likely due to increased heart rate, blood pressure, tightening of blood vessels and increased clotting, all associated with triggering heart attacks," he said.

The study was an investigation of consecutive patients suspected of heart attack and confirmed by angiography reports at Royal North Shore hospital. Patients confirmed with acute coronary blockage were admitted, interviewed about their activities in the 48 hours before the onset of symptoms, and usual frequencies of activities were recorded for comparison.

"Although the incidence of anger-triggered heart attacks is around 2%, of the sample, those people were 8.5 times more likely to have a heart attack within two hours of the emotional episode. So while the absolute risk of any one episode triggering a heart attack is low, this data demonstrates that the danger is very present.

"Our findings highlight the need to consider strategies to protect individuals most at risk during times of acute anger.

Senior author Professor Geoffrey Tofler, Preventive Cardiology, University of Sydney said "Potential preventive approaches may be stress reduction training to reduce the frequency and intensity of episodes of anger, or avoiding activities that usually prompt such intense reactions, for instance, avoiding an angry confrontation or activity that provokes intense anxiety.

"Additionally, improving general health by minimising other risk factors, such as hypertension, high cholesterol or smoking would also lower risk.

"For those at high risk, it is possible that medication such as beta-blockers and aspirin taken at the time of a trigger may interrupt the link between the stressor and the heart attack. We are currently recruiting subjects for a study examining this option.

"Our research suggests that when managing a person with heart disease or in preventing heart disease in others, a person's frequency of anger and anxiety should also be assessed and be part of helping individuals to take care of themselves.

"Our message to people is they need to be aware that a burst of severe anger or anxiety could lead to a coronary event, so consider preventative strategies where possible," Dr Tofler said.

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Story Source:

The above story is based on materials provided by University of Sydney. Note: Materials may be edited for content and length.

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Journal Reference:

1.         Geoffrey H Tofler et al. Triggering of acute coronary occlusion by episodes of anger. European Heart Journal: Acute Cardiovascular Care, February 2015 DOI: 10.1177/2048872615568969 

We went out for a walk in the snow this weekend