The Chicago Journal

Anxiety can come from the heart, a mice study found

Anxiety Many studies on mental health have been conducted over the last several decades with the objective of aiding millions of people worldwide.

Anxiety is one of the most common mental illnesses, affecting around 30% of people and causing their hearts to beat.

Some, on the other hand, think that their beating heart adds to their anxiety.

Until now, a new mouse study found that they both belonged to the same group.

A new finding

The study, published in the March 9 issue of Nature, shows that in high-risk settings, a beating heart sends signals to the brain, increasing anxiety.

The findings may offer a new perspective on understanding and treating anxiety disorders.

Scientists observed anxiety-like behavior in mice after artificially increasing their heart rates.

They then calmed the mice by turning off a part of their brain.

The brain and emotions

According to Stanford University neuroscientist Karl Deisseroth, William James, the pioneer of psychology, proposed that physical experiences may contribute to emotions in the brain.

In his 1890 book The Principles of Psychology, James created the thesis that emotion follows what the body goes through, writing:

“We feel sorry because we cry, angry because we strike, afraid because we tremble.”

Interoception is the phenomenon in which the brain feels impulses within the body.

Nevertheless, neuroscientist Anna Beyeler of the French National Institute of Health and Medical Research in Bordeaux feels that determining whether these experiences contribute to emotion is impossible.

Beyeler analyzes brain networks connected with emotion and makes the following comment on his findings:

“I’m sure a lot of people have thought of doing these experiments, but no one really had the tools.”

Read also: Insomnia linked to heart attacks in new studies

The new study

Karl Deisseroth spent the most of his career developing devices for this kind of study.

He is one of the scientists that developed optogenetics, a method that utilizes viruses to modify the genes of certain cells so that they respond to light flashes.

With a light switch, scientists can regulate the activity of the cells.

In the current work, Deisseroth and his colleagues used a tiny vest with a light to change the heart rhythm of a mouse with a genetically altered heart.

When the mouse was switched off, its heart rate was around 600 beats per minute.

At 900 beats per minute, the mouse’s heartbeat was synced with the flashing light.

“It’s a nice reasonable acceleration [one mouse] would encounter in a time of stress or fear,” said Deisseroth.

When their hearts began to speed, the mice began to exhibit anxiety-like behavior.

In stressful situations, mice tend to retreat to the walls and hide in dark corners.

In another instance, when pressing a water lever resulted in a little shock every now and again, mice with normal heart rates pressed on it without hesitation.

Mice with a pounding heart, on the other hand, would become thirsty.

“Everybody was expecting that, but it’s the first time that it has been clearly demonstrated,” said Beyeler.

Brain scans

The researchers analyzed the mice’s brains for areas that may be processing the increased heart rate.

One of the most notable signals, according to Deisseroth, came from the posterior insula.

“The insula was interesting because it’s highly connected with interoceptive circuitry,” he said.

“When we saw that signal, [our] interest was definitely piqued.”

Further optogenetics were utilized to suppress activity in the posterior insula, which lowered the mice’s anxiety-like behaviors.

Although their hearts were still hammering, the animals behaved normally, spending more time in open areas of the mazes and pressing water levers without reluctance.

What next?

According to Wen Chen, branch chief of basic medical research for complementary and integrative health at the National Center for Complementary and Integrative Health in Bethesda, the study’s findings caught the curiosity of many people.

“No matter what kind of meetings I go into, in the last two days, everybody brought up this paper,” said Chen.

The next step, according to Karl Deisseroth, is to look at other physical regions that may impact anxiety.

“We can feel it in our gut sometimes, or we can feel it in our neck or shoulders,” he said.

Using optogenetics, scientists may tense a mouse’s muscles or give it butterflies in the stomach to reveal new circuits that trigger fear or anxiety-like responses.

Yet, Beyeler believes that understanding the heart-brain connection might help doctors manage fear and anxiety.

The trip from the laboratory to the clinic, however, is more convoluted than the path from the heart to the head.

Image source: PETA

Mental health becomes concern following studies

Image source: Mashable

Mental health: The brains of teenagers in the US changed during the Covid-19 pandemic, causing them to age faster than average, according to studies.

Younger study participants reported more severe symptoms of anxiety, depression, and internalized problems.

Internalized problems typically include feelings of sadness, low self-esteem, anxiety, and difficulty regulating emotions.

The symptoms all appeared after the first year of the pandemic.

Factors

Recent studies reveal multiple factors that caused adolescent mental health to suffer during the pandemic.

Teens were pulled out of school and separated from friends and support structures.

Many were forced to live with fear and uncertainty the Coronavirus brought.

Additionally, teens witnessed their parents losing their jobs while millions lost their parents and loved ones to the Coronavirus.

The study

Titled Biological Psychiatry: Global Open Science, the study is among the first to examine physical changes in the brain caused by stress and anxiety.

The paper was also published last Thursday.

The research comes from a more extensive study in which scientists tried to understand gender differences in adolescent depression.

Eight years ago, scientists launched a plan to perform MRI scans on 220 children aged 9 and 13 every two years.

The team conducted two rounds of analysis before the pandemic halted their research.

As a result, they had to wait until late 2020 to resume the scanning.

Read also: Portland woman breaks into another apartment and raises mental health help concerns

The brain

By then, scientists determined that the children affected by the 2020 pandemic had brains older than their chronological age.

The brain had growths in the amygdala and hippocampus.

The amygdala is the area regulating anxiety and stress, while the hippocampus is the area controlling access to memories.

During this time, tissues in the cortex, the part of the brain that controls executive functions, have thinned.

While a child’s brain naturally changes over time, research has shown that physical changes can happen more quickly in the face of significant adversity.

Other studies show that the brains of people who experience abuse, neglect, poverty and family problems early in life age faster.

They are also prone to later mental health issues.

Findings

The study’s lead author is Ian Gotlib, who teaches psychology at Stanford University.

He said the team expected to find a problem behind anxiety and depression.

However, they weren’t sure what they’d find with the MRI scans.

“The pandemic has not been kind to adolescent mental health,” said Gotlib.

“It’s always interesting to do research like this when you’re not really sure what’s going to happen.”

“These effects were interesting and happened pretty quickly.”

“This wasn’t just a one-year shutdown,” Gotlib added.

“So we didn’t know that the effects on the brain would be this pronounced after that short a period of stress.”

“It tracks with the mental health difficulties that we’re seeing.”

Ian Gotlib says it is unclear whether brain changes will have an impact as they grow older.

Future plans

Ian Gotlib’s team plans to examine ten children from the study who had Covid-19 to see if there is a different effect.

He noted that the physical difference is more pronounced in children with Covid-19.

Meanwhile, the diversion chief of pediatric neurology at UH Rainbow Babies & Children’s Hospital, Dr. Max Wiznitzer, agreed that the brain changes were interesting.

However, he stressed whether the mental health issues persist is more important.

“The anatomy is not important,” said Wiznitzer, who was uninvolved with the research.

“It’s the functionality that’s important.”

“The clinical consequence here is the functional impact, the mental health condition clinically and how it’s functioning and how you deal with it.”

Wiznitzer also said that people can manage anxiety or depression with the right mental health interventions.

“The brain has that capacity for reorganization – or call it improvement, if you will,” said Wiznitzer.

Read also: Dylan Sessler’s One-on-One Mental Health Coaching Helps People Overcome Their Struggles

Other notes

Ian Gotlib is hopeful that parents and guardians will remember that mental health consequences can linger despite the end of lockdowns and school closures.

“Be sure that your adolescent or your teen is getting any help that he or she, that they, might need if they’re experiencing symptoms of depression, anxiety or being withdrawn.”

Reference:

Teens’ brain aged faster during the first year of the pandemic, study says, and stress may be to blame