Adults Sought for Study on Aging and Mobility

                                                               Walking stickman
The Biomechanics Laboratory in the kinesiology department is recruiting volunteers for a study about the effects of age and exercise on walking and muscle function. The researchers hope to learn about how changes in muscle function with age are related to the onset of disability.

The lab is looking for individuals who meet the following criteria: ages 55-70 with healthy body weight who participate in fewer than five 30-minute bouts of exercise per week (or less than a total of 150 minutes of planned exercise per week), no history of reconstructive surgery of the legs, no major health issues (heart disease, diabetes, neurological disease), able to walk for 30 minutes and no contraindications to MRI (metal implant, claustrophobia).

The study consists of two visits: a 1-hour visit to an MRI facility in Amherst and one 3-hour visit to the Biomechanics Lab on campus. During the lab visit researchers will collect data on how participants’ joints move as they walk over the ground and on a treadmill. The study will also collect data on the strength of the muscles in participants’ thighs. All procedures are non-invasive.

Source: UMass

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Alcohol interferes with body's ability to regulate sleep

At right: Mahesh Thakkar, PhD, associate professor and director of research in the MU School of Medicine’s Department of Neurology, and Pradeep Sahota, MD, chair of the MU School of Medicine’s Department of Neurology, have studied alcohol’s effects on sleep for more than five years. Their study found that drinking interferes with the brain’s built-in system for regulating a person’s need for sleep. Credit: Image courtesy of University of Missouri-Columbia

Researchers from the University of Missouri School of Medicine have found that drinking alcohol to fall asleep interferes with sleep homeostasis, the body's sleep-regulating mechanism.

Alcohol is known to be a powerful somnogen, or sleep inducer, and approximately 20 percent of the U.S. adult population drinks alcohol to help fall asleep. The researchers, led by Mahesh Thakkar, PhD, associate professor and director of research in the MU School of Medicine's Department of Neurology, have studied alcohol's effects on sleep for more than five years. They found that alcohol interferes with the brain's built-in system for regulating a person's need for sleep.

"The prevailing thought was that alcohol promotes sleep by changing a person's circadian rhythm -- the body's built-in 24-hour clock," Thakkar said. "However, we discovered that alcohol actually promotes sleep by affecting a person's sleep homeostasis -- the brain's built-in mechanism that regulates your sleepiness and wakefulness."

Sleep homeostasis balances the body's need for sleep in relation to how long a person has been awake. If an individual loses sleep, the body produces adenosine, a naturally occurring sleep-regulating substance that increases a person's need for sleep. When a person goes to sleep early, sleep homeostasis is shifted and he or she may wake up in the middle of the night or early morning. The researchers found that alcohol alters the sleep homeostatic mechanism and puts pressure on an individual to sleep. When this happens, the sleep period is shifted, and a person may experience disrupted sleep.

"Based on our results, it's clear that alcohol should not be used as a sleep aid," said Pradeep Sahota, MD, chair of the MU School of Medicine's Department of Neurology and an author of the study. "Alcohol disrupts sleep and the quality of sleep is diminished. Additionally, alcohol is a diuretic, which increases your need to go the bathroom and causes you to wake up earlier in the morning."

In addition to studying alcohol's impact on sleep homeostasis, the researchers explored how alcohol withdrawal affects sleep. The investigators found that after extended periods of frequent drinking, subjects would fall asleep as expected, but would wake within a few hours and would be unable to fall back asleep. When the subjects were not given alcohol, the researchers found that subjects showed symptomatic insomnia.

"During acute alcohol withdrawal, subjects displayed a significant increase in wakefulness with a reduction in rapid eye movement and non-rapid eye movement sleep," Thakkar said. "This caused insomnia-like symptoms and suggests an impaired sleep homeostasis."

The researchers hope to use these findings to explore other effects of alcohol consumption.

"Sleep is an immense area of study," Thakkar said. "Approximately one-third of our life is spent sleeping. Coupled with statistics that show 20 percent of people drink alcohol to sleep, it's vital that we understand how the two interact. If you are experiencing difficulty sleeping, don't use alcohol. Talk to your doctor or a sleep medicine physician to determine what factors are keeping you from sleeping. These factors can then be addressed with individualized treatments."

The study, "Alcohol Disrupts Sleep Homeostasis," is an invited article published in the international biomedical journal Alcohol.

Source:  University of Missouri-Columbia

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‘Smart’ drugs won’t make smart people smarter, research concludes

Dr. Ahmed Dahir Mohamed is in the School of Psychology at The University of Nottingham Malaysia Campus. Credit: The University of Nottingham

The study carried out by Dr Ahmed Dahir Mohamed, in the School of Psychology at The University of Nottingham Malaysia Campus, and published in the open access journal PLOS ONE, showed the drug had negative effects in healthy people.

Dr Mohamed said: "We looked at how the drug acted when you are required to respond accurately and in a timely manner. Our findings were completely opposite to the results we expected."

In a randomised double blind study, 'Modafinil increases the latency of response in the Hayling Sentence Completion Test in Healthy Volunteers: A Randomised Controlled Trial', they administered 32 participants with the drug and 32 with a placebo. All the participants were given a famous neuropsychological task known as the Hayling Sentence Completion Test in which they were asked to respond both quickly and accurately. Dr Mohamed found the drug slowed down reaction times, impaired their ability to respond in a timely manner and failed to improve their performance of the task.

Dr Mohamed said: "It has been argued that Modafinil might improve your performance by delaying your ability to respond. It has been suggested this 'delay dependent improvement' might improve cognitive performance by making people less impulsive. We found no evidence to support those claims.

"Our research showed that when a task required instant reactions the drug just increased reaction times with no improvement to cognitive performance."

This backs up the findings of a previous study carried out by Dr Mohamed and published in September 2014 in The Journal of Creative Behaviour. The study: The Effects of Modafinil on Convergent and Divergent Thinking of Creativity: A Randomised Controlled Trial showed that the so called 'smart' drug impaired the participant's ability to respond in a creative way particularly when they were asked to respond laterally -- outside the box.

Does Modafinil benefit anyone?

When Dr Mohamed looked at participant's ability to problem solve in a creative manner he found that those who weren't particularly creative to start with were improved by the drug while those who were creative were impaired by the drug. He said: "Our study backs up previous research that suggests psychostimulants improve people at the lower end of the spectrum in cognition whereas they impair people who are at the optimum level of cognitive function -- healthy people for example. It looks like Modafinil is not helpful for healthy individuals and it might even impair their ability to respond and might stifle their lateral thinking, while people who have some sort of deficiency in creativity are helped by the drug."

What can make us smarter?

Ahmed Mohamed's research was carried out while he was at Cambridge University. He has since moved to The University of Nottingham Malaysia Campus where he will be looking at the effects of non-pharmacological interventions, such as meditation, exercise and diet on the healthy brain. He is also currently using Electroencephalography (EEG) to study how mindfulness can affect the healthy adolescent brain.

Dr Mohamed said: "What I have found in my doctoral studies is that if you are already a healthy person and functioning at an optimum level, it is really difficult to improve your cognition. But the brain of the adolescent is still in development and you might be able to improve cognition at this stage of our development through positive interaction, healthy diet or mindfulness."

Source: University of Nottingham

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