October Neuroscience Round-Up for Mindful Leaders

By The Mindful Leader Team

For this month’s Round-Up, we look at the science behind mental exhaustion, what we can learn from the brains of seniors, the value of listening to silence, the relationship between a lost sense of time and mental distress, and finally, the phenomenon of lucid dreaming. We have summarized the main ideas and key takeaways below with links to the full articles.

Study Explains the Likely Cause of Mental Exhaustion  

Why does mental labor make you feel as tired as physical labor? According to a recently published study, it may have to do with the need to recycle potentially toxic byproducts that are produced by intense neural activity (i.e. thinking hard). Researchers used magnetic resonance spectroscopy to measure brain chemistry throughout the day in individuals with either cognitively demanding jobs or jobs requiring undemanding mental tasks. Signs of fatigue were only observed in the group with cognitively demanding jobs, and these same individuals were more likely to seek instant gratification when work was over. Cognitive tasks become more taxing after hours of intense mental labor, so it’s best to avoid making important decisions at the end of a long, mentally-draining day.

Key Points:

• This research suggests that mental exhaustion is the result of a functional change in the brain, a build-up of harmful substances, specifically glutamate, in the prefrontal cortex. This accumulation makes cognition more challenging and energetically costly.
• The best way to recover from your mental exhaustion is rest and sleep. Previous scientific evidence shows that glutamate is naturally eliminated from the brain synapses (and therefore decreased) during sleep.
• You can help limit your mental fatigue and avoid burnout by protecting your energy — set boundaries (especially when using technology), avoid multitasking, and consider a daily meditation routine to improve focus and reduce distractibility.

Read the full article here. 

Mental Skills Slow With Age, But Seniors Gain in Other Ways, Study  

Cognitive ability declines with age, but mental health seems to improve. People over 60 years old generally have better psychological health than those in their 20s. To explore this interplay between cognition and mental wellbeing, researchers recruited 62 young participants and 52 old participants and surveyed their mental health, including measures of anxiety, depression, loneliness, and overall mental wellbeing. Then, EEG was used to measure brain activity while participants performed several mentally demanding tasks. The findings demonstrate that different regions of the brain are activated during cognitive tasks, depending on your age. 

Key Points:

• Older participants showed greater activation of the default mode network (associated with mind-wandering, rumination, and daydreaming) during cognitive tasks. Mindfulness meditation training can help suppress this network and prevent getting distracted when thinking about the task at hand.
• While younger participants had greater activity in regions associated with executive control (dorsolateral prefrontal cortex), older participants seemed to compensate for the age-related decline in this region by relying more on the inferior frontal cortex, an area that helps focus attention and eliminate distraction.
• Further study of the brains of older individuals may provide insight into how younger people can improve their mental wellbeing.

Read the full article here. 

How Listening to Silence Changes Our Brains  

The world continues to get louder and louder with noise pollution continuing to double or triple every three decades. Ambulance sirens are six times louder than they were 100 years ago; they need to be in order to cut through all the sounds of our modern world. We already know how harmful noise can be. Noises trigger the release of stress hormones, and excessive noise exposure can increase your risk for hearing loss, cardiovascular disease, stroke, and depression. Aside from the absence of noise, does silence have any additional value? According to a study performed at Duke University, the answer is a resounding yes. Researchers placed mice inside anechoic chambers (soundless booths) for two hours a day before testing the effect of five types of sounds on their brains: white noise, mice pup noises, a Mozart piano sonata, ambient noise, and silence. After each noise exposure, they measured cell growth in the hippocampus (brain region largely associated with memory) of each mouse.

Key Points:

• Of the five sounds, silence resulted in the highest growth of neurons in the mice hippocampus. For mice in their natural environment, silence is the most atypical sound, and thus the most arousing and alerting.
• The researchers note that listening to silence is more than just relaxation — it can actually elicit a positive stress called eustress, and this exertion is likely responsible for stimulating the growth of valuable brain cells.
• Whether you have a meditation practice or not, you can reap the cognitive and health benefits of eustress simply by stopping for a few moments and taking the time to listen in silence. 

Read the full article here. 

How living in a pandemic distorts our sense of time  

Since Spring 2020, time has felt entirely out of whack, a phenomenon colloquially coined “Blursday”. A warped sense of time like this can negatively impact people’s wellbeing . Back in the 90s, psychologist Alison Holman interviewed survivors of the 1993 California wildfires and found that two years later, individuals who had lost their temporal bearings during the fire were still experiencing higher levels of distress compared to those who had maintained their sense of time. Concerning the pandemic, surveys conducted during the first six months found that over two-thirds of people reported feeling “strangely out of sync”. For some, it’s easy to shake off this weird feeling and move on, but for others, this lingering temporal distortion could lead to mental distress and decreased health down the line. 

Key Points:

• Participants aged 18-29 and women reported greater feelings of time distortion, which puts them at a higher risk of developing mental health problems.
• Research suggests that those who experience time as moving slowly tend to have less mental distress (including increased feelings of loneliness) than those who experience time as moving fast. Remembering a “longer pandemic” (i.e. one that lasted for a longer time) can make it feel more recent, and therefore, more present. 
• Mindfulness training can help people overcome distortions in time by bringing them back to the present. However, in the unique instance of the ongoing pandemic, it’s important that people also actively focus on (re)building a vision for the future.

Read the full article here. 

Scientists spoke to people in their sleep. They responded. What’s lucid dreaming?  

Lucid dreaming occurs when someone becomes aware they are dreaming. From that moment on, they can even control what they do in their dream. They might decide to fly through the sky, for instance. Roughly 20% of people are regular lucid dreamers, but it’s estimated that at least half of us will experience it once in our lifetime. Some people find themselves lucid dreaming by accident, while others use specific training techniques to encourage it (like repeating, “next time I’m dreaming, I’ll remember I’m dreaming”). It’s still not clear exactly how or why lucid dreaming occurs, but Professor Paller has started to study it in the lab and has successfully trained participants to signal researchers (via eye movements or nose sniffs) the moment they begin to lucid dream; sometimes, participants can even successfully answer math problems presented to them.

Key Points:

• The brain of someone who is lucid dreaming looks more like the brain of someone awake rather than sleeping and shows increased activity in the regions used for critical thinking.
• Researchers theorize that lucid dreaming may be a sort of hybrid state of consciousness, similar to sleep paralysis or sleep walking, in which some regions of the brain are awake and others asleep. 
• Lucid dreaming has the potential to treat PTSD and nightmares, inspire creativity, and help us prepare for future tasks in the form of a “sleep rehearsal”. However, future research is also needed to better understand the potential risks, such as if and how lucid dreaming may interfere with necessary sleep processes, including memory consolidation.

Read the full article here.