Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Laughter helps blood vessels function better

08.03.2005


Volunteers were shown funny and disturbing movies to test the effect of emotions on blood vessels



Using laughter-provoking movies to gauge the effect of emotions on cardiovascular health, researchers at the University of Maryland School of Medicine in Baltimore have shown for the first time that laughter is linked to healthy function of blood vessels. Laughter appears to cause the tissue that forms the inner lining of blood vessels, the endothelium, to dilate or expand in order to increase blood flow.

When the same group of study volunteers was shown a movie that produced mental stress, their blood vessel lining developed a potentially unhealthy response called vasoconstriction, reducing blood flow. That finding confirms previous studies, which suggested there was a link between mental stress and the narrowing of blood vessels.


The results of the study, conducted at the University of Maryland Medical Center, will be presented at the Scientific Session of the American College of Cardiology on March 7, 2005, in Orlando, Florida.

The endothelium has a powerful effect on blood vessel tone and regulates blood flow, adjusts coagulation and blood thickening, and secretes chemicals and other substances in response to wounds, infections or irritation. It also plays an important role in the development of cardiovascular disease.

"The endothelium is the first line in the development of atherosclerosis or hardening of the arteries, so, given the results of our study, it is conceivable that laughing may be important to maintain a healthy endothelium, and reduce the risk of cardiovascular disease," says principal investigator Michael Miller, M.D., director of preventive cardiology at the University of Maryland Medical Center and associate professor of medicine at the University of Maryland School of Medicine. "At the very least, laughter offsets the impact of mental stress, which is harmful to the endothelium."

The study included a group of 20 non-smoking, healthy volunteers, equally divided between men and women, whose average age was 33. The participants had normal blood pressure, cholesterol and blood glucose levels. Each volunteer was shown part of two movies at the extreme ends of the emotional spectrum. They were randomized to first watch either a movie that would cause mental stress, such as the opening scene of "Saving Private Ryan" (DreamWorks, 1998), or a segment of a movie that would cause laughter, such as "King Pin" (MGM, 1996). A minimum of 48 hours later, they were shown a movie intended to produce the opposite emotional extreme.

Prior to seeing a movie, the volunteers fasted overnight and were given a baseline blood vessel reactivity test to measure what is known as flow-mediated vasodilation. For that test, blood flow in the brachial artery in the arm was restricted by a blood pressure cuff and released. An ultrasound device then measured how well the blood vessel responded to the sudden increase in flow.

Volunteers watched a 15-minute segment of the movie while lying down in a temperature-controlled room. After the movie was shown, the brachial artery was constricted for five minutes and then released. Again, ultrasound images were acquired. Changes in blood vessel reactivity after the volunteers watched a movie lasted for at least 30 to 45 minutes. A total of 160 blood vessel measurements were performed before and after the laughter and mental stress phases of the study.

There were no differences in the baseline measurements of blood vessel dilation in either the mental stress or laughter phases. But there were striking contrasts after the movies were seen. Brachial artery flow was reduced in 14 of the 20 volunteers following the movie clips that caused mental stress. In contrast, beneficial blood vessel relaxation or vasodilation was increased in 19 of the 20 volunteers after they watched the movie segments that generated laughter. Overall, average blood flow increased 22 percent during laughter, and decreased 35 percent during mental stress.

Several volunteers had already seen "Saving Private Ryan," says Dr. Miller, but even so, some of them were among the 14 with reduced blood flow.

"The magnitude of change we saw in the endothelium is similar to the benefit we might see with aerobic activity, but without the aches, pains and muscle tension associated with exercise," says Dr. Miller. "We don’t recommend that you laugh and not exercise, but we do recommend that you try to laugh on a regular basis. Thirty minutes of exercise three times a week, and 15 minutes of laughter on a daily basis is probably good for the vascular system."

Dr. Miller says this study was not able to determine the source of laughter’s benefit. "Does it come from the movement of the diaphragm muscles as you chuckle or guffaw, or does it come from a chemical release triggered by laughter, such as endorphins?" he asks. Dr. Miller says a compound called nitric oxide is known to play a role in the dilation of the endothelium. "Perhaps mental stress leads to a breakdown in nitric oxide or inhibits a stimulus to produce nitric oxide that results in vasoconstriction," says Dr. Miller.

The current study builds on earlier research Dr. Miller conducted on the potential benefits of laughter, reported in 2000, which suggested that laughter may be good for the heart. In that study, answers to questionnaires helped determine whether people were prone to laughter and ascertain their levels of hostility and anger. Three hundred volunteers participated in the study. Half of them had suffered a heart attack or had undergone coronary artery bypass surgery; the other half did not have heart disease. People with heart disease responded with less humor to everyday life situations than those with a normal cardiovascular system.

Dr. Miller says certain factors in the earlier study may have affected the results. For example, he says it may be that people who have already had a coronary event are not as laughter-prone as those who do not have heart disease.

He says the current study sought to eliminate that uncertainty by using volunteers whose cardiovascular system was healthy. The results of the brachial artery blood flow measurements, which are precise and objective, appear to make the connection between laughter and cardiovascular health even stronger, according to Dr. Miller.

Bill Seiler | EurekAlert!
Further information:
http://www.umm.edu

More articles from Health and Medicine:

nachricht NTU scientists build new ultrasound device using 3-D printing technology
07.12.2016 | Nanyang Technological University

nachricht How to turn white fat brown
07.12.2016 | University of Pennsylvania School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>