Tag: hypnotherapy

Secondhand Trauma — Is It Real? The 2017 Hurricane Season Is Affecting Everyone

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As we have all witnessed in the last few months, 2017 has produced an incredibly destructive hurricane season. For many of us not living in the affected areas, just watching the devastation on TV and hearing about it on the radio or social media can also cause a deep sense of fear and anxiety.

It can even cause many to suffer secondhand trauma or more specifically, Secondary Trauma Stress (STS). STS is a psychiatric condition which mimics symptoms of Post-Traumatic Stress Disorder (PTSD). It affects individuals who did not witness the traumatic event firsthand but were still exposed to it in other ways.

When we are faced with crisis situations of this magnitude like floods, hurricanes, earthquakes, fires, war, terrorism, etc., we feel our sense of safety and security is compromised — we experience trauma. This kind of emotional devastation can make us fearful for ourselves and for our loved ones. For most people this anxiety and worry is manageable, but for others it can become incapacitating. Trauma is fear on steroids.

Hence, symptoms that resemble Post-Traumatic Stress Disorder can develop even by experiencing it from afar. Secondhand trauma is indeed real.

According to the DSM-V, PTSD is a debilitating anxiety disorder manifesting after a traumatic experience that involves an actual or perceived threat of death or serious injury. Research shows that about 8% of Americans will experience PTSD at some point in their lives. Women are more likely to be effected than men.

Remember, anxiety is first and foremost a critical survival mechanism. It’s a vital throwback function dating back to our ancestors, so understanding its adaptive function is important.

The part of your brain called the amygdala, or the fear center, is your private 911 operator. It’s the first responder to any perceived threat even if the threat is thousands of miles away. The brain then dispatches the signal to the body increasing blood pressure, heart rate, etc. Vital hormones like cortisol and adrenaline are then sent into the blood stream which gets the body ready for fight-or-flight (the body’s own built-in defense response system).

It’s essential to understand that if evolution put anxiety there to safeguard us from injury, it has to be fail-safe, meaning it has to work every time no matter what. What’s the point of having a 911 operator that is incredulous or unsure? Otherwise humans would have perished as a species a long time ago.

Since it’s an iron-clad system, it also means it cannot always distinguish between real fears and imagined fears. For example, being late for an important meeting or dreading going to the dentist may feel as frightening as having a gun to your head or being chased by a hungry bear. Therefore you may also struggle to distinguish between disasters close to home that could happen to you and ones that are far away and unlikely to happen to you.

So, despite how it makes us feel and how debilitating it can be, anxiety can also be an ally. At times it may feel like a dubious partner, but either way we need to coexist with it.

Signs to pay attention to if you have been affected by the “emotional devastation” of the recent disasters.

  • Do you excessively worry about loved ones affected by the recent hurricanes? Do you excessively worry about anyone suffering from the effects of these hurricanes? Strangers too.
  • Do you feel super anxious, fearful, panicked? Do you have heart palpitations? Racing thoughts and labored breathing?
  • Do you feel numb, detached or lacking in emotional responsiveness?
  • Do you experience increased arousal? Do you feel irritable, angry, have trouble concentrating? Do you have trouble sleeping?
  • Do you re-experience images or flashbacks of the devastation throughout the day? Do you have recurring bad dreams or nightmares about it?
  • Do you avoid situations, places or even people that remind you of it?

Here are some tips to help manage your anxiety:

Accept that you DON’T have control. Accept that you don’t have control over much at all, especially not natural disasters. Keep a healthy perspective and try to focus on what you DO have control over, like your job, taking care of your kids, keeping your home safe, caring for others, etc.

Accept your fear. It’s natural to feel scared. Allow yourself to acknowledge the anxiety as a natural component of your fight/flight response system which is there to help protect the body from harm. God or evolution did not put it there to harm you. It is there to protect you.

Don’t isolate. Stay connected. Fears are fleeting, but human contact is solid and reliable. Connect with others and talk about your fears and concerns. Maintaining social contacts and engaging in activities can help preserve a sense of healthy consistency and provide meaningful opportunities for sharing feelings and relieving tension.

Maintain a sense of normalcy. Don’t change the composition of your day-to-day living. Keep routines active. Keep engaging in hobbies, meeting with your friends, going to the movies, to dinner, etc. A sense of normalcy and daily structure also helps to keep your perspective healthy and leaves less opportunity for the mind to wander off and over-magnify your fears.

Limit your exposure to media coverage. We all know that staying informed is a good thing to do in these crisis situations, but too much exposure can heighten fears and cause your anxiety to escalate. Your mind can only take so much.

And lastly, if your symptoms of anxiety begin to overwhelm you and it impairs your ability to function on a day to day basis, seek professional help. Reach out to a trained counselor or a mental health clinician for guidance and support. Remember, anxiety and phobias are treatable conditions that should never be underestimated.

September 22, 2017 at 02:19PM

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Alzheimer’s disease: When does personality start to change?

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woman looking confusedMood swings and apathy are known to affect the personality of those living with Alzheimer’s disease.

A new study recently published in the journal JAMA Psychiatry investigates whether or not changes in personality precede the onset of mild cognitive impairment or dementia.

The researchers – who were jointly led by Antonio Terracciano and Angelina Sutin, both associate professors at Florida State University College of Medicine in Tallahassee – investigated dementia-related personality changes in a cohort of more than 2,000 people.

The longitudinal study followed these participants for 36 years, during which time the researchers looked for increased neuroticism, decreased conscientiousness, and other personality changes.

It is known that personality and behavioral changes accompany Alzheimer’s disease. Caregivers report irritability, moodiness, or loss of motivation in their patients, which negatively affect their quality of life.

These are clinical criteria for diagnosing the illness, but it remains debatable whether or not these changes occur before the onset of dementia – as a consequence of the brain pathologies that characterize the disease and occur years before a formal diagnosis – or whether personality changes are just independent risk factors for the condition.

Personality stays the same before onset

For the new study, 2,046 participants were recruited from the Baltimore Longitudinal Study of Aging. Of them, 45.5 percent were female, and the average age was 62 years.

During the follow-up period, little over 5 percent of the participants developed mild cognitive impairment (MCI) and 12.5 percent developed dementia. The majority of these patients had Alzheimer’s disease.

MCI describes a level of cognitive decline that affects seniors. Although it is not serious enough to interfere with the daily functioning of those it affects, MCI is considered to be a strong predictor of Alzheimer’s disease.

Prof. Terracciano and colleagues used the Revised NEO Personality Inventory to assess changes in personality traits, as they were observed and reported by the participants themselves.

The questionnaire assessed five different personality dimensions: “neuroticism, extraversion, openness, agreeableness, and conscientiousness.”

The researchers examined the “slopes” that depicted personality changes over time, and they compared the trajectories of those who went on to develop dementia or MCI with those of cognitively healthy participants.

Having adjusted for age, sex, race, and education, the researchers found that “change in personality […] was not significantly different between the non-impaired and the Alzheimer’s disease group.”

When compared with healthy individuals, participants who developed MCI did not exhibit any personality changes, either.

In other words, the study found that the personalities of people with Alzheimer’s disease remain unchanged before the onset of the condition.

We further found that personality remained stable even within the last few years before the onset of mild cognitive impairment.”

Prof. Antonio Terracciano

Additionally, the study adds to the evidence showing that certain personality traits, such as high levels of neuroticism, can increase the risk of dementia.

The authors write that these results “provide evidence against the reverse causality hypothesis.” This hypothesis refers to the possibility that changes in personality are a consequence of Alzheimer’s neuropathology, such as the build-up of amyloid plaque in the brain.

But the findings strengthen the idea that certain personality traits associated with Alzheimer’s disease are, in fact, independent risk factors for the condition, rather than a consequence of it.

Strengths and limitations of the study

Speaking about the study’s strengths, Prof. Terracciano says, “Unlike previous research, this study examined multiple waves of self-rated personality data collected up to 36 years before participants developed any sign of dementia.”

In addition to the long-term follow-up, the authors list the considerable sample size and the “in-depth personality and clinical assessments” as strengths of the study.

However, they also admit some limitations to their research. For one thing, the sample was limited to people with a higher level of education.

Also, participants who did not develop dementia during the follow-up tended to be younger on average, so the authors concede that these people may go on to develop dementia in the future.

Finally, the authors note that some personality traits might make some people resilient to the brain pathology that characterizes Alzheimer’s disease. More research is warranted in this direction.

September 22, 2017 at 02:02PM

12 Jobs That Make People Most Satisfied

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…and the 12 linked to the least satisfaction with life.

The clergy are the happiest and most satisfied workers in America, a large US survey finds.

87% of them reported being very satisfied with their work.

They are closely followed by physical therapists, 80% of whom were very satisfied with their work and firefighters, 78% of whom were very satisfied.

Dr Tom W. Smith, the study’s author, explained the common thread in these different jobs:

“The most satisfying jobs are mostly professions, especially those involving caring for, teaching, and protecting others and creative pursuits.”

Here is the full list of the top 12 most satisfying jobs:

1. Clergy
2. Physical Therapists
3. Firefighters
4. Education Administrators
5. Painter, Sculptors, Related
6. Teachers
7. Authors
8. Psychologists
9. Special Education Teachers
10. Operating Engineers
11. Office Supervisors
12. Security & Financial Services Salespersons

Rev. Cynthia Lindner, Director of Ministry Studies at the University of Chicago’s Divinity School, said:

 “Persons engaged in ministry have great opportunity to live and work out of their deepest convictions, oftentimes in the midst of communities of faith who share their concern for meaning, compassion and justice.

This congruence of belief, values, and actions in one’s daily work can be immensely satisfying.”

Across all the occupations, 47% of people reported being very satisfied with their jobs and 33% said they were very happy with their lives in general.

Down at the bottom of the list, the 12 least satisfying jobs were:

1. Roofers
2. Waiters/Servers
3. Laborers, Except Construction
4. Bartenders
5. Hand Packers and Packagers
6. Freight, Stock, & Material Handlers
7. Apparel Clothing Salespersons
8. Cashiers
9. Food Preparers
10. Expediters
11. Butchers & Meat Cutters
12. Furniture/Home Furnishing Salespersons

These jobs are generally low-paid and often involve manual labour.

Customer service and food/beverage preparation was also particularly unsatisfying, according to the survey.

Over 27,000 people were interviewed for the survey across a wide variety of social classes and occupations.

→ Try one of PsyBlog’s ebooks, all written by Dr Jeremy Dean:

The study was published by the National Opinion Research Center at the University of Chicago (Smith, 2007).

September 22, 2017 at 01:21PM

Long-term sexual satisfaction: What’s the secret?

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CoupleIs there a secret to a fulfilling sex life?

Once the flutters of a new relationship are over, for many, the slog of everyday life sets in. But how do you keep the spark alive?

Sex is a key factor in most romantic relationships. In fact, earlier this year, Medical News Today reported that the “afterglow” that newlywed couples feel for up to 2 days after having sex is associated with greater marital satisfaction.

But last week, a new study showed that 34 percent of women and 15 percent of men who had lived with their partner for at least 1 year had lost interest in sex.

There are many factors that can affect sexual desire. Find out how much sex has the greatest effect on happiness, why some people lose interest, and what factors contribute to long-term sexual satisfaction.

How much sex is enough?

In a 2016 paper, Amy Muise, Ph.D. – a postdoctoral fellow in the Department of Psychology at the University of Toronto Mississauga in Canada – explains that there is plenty of evidence that “[…] the more sex people reported, the happier they felt.”

However, Dr. Muise also questions whether trying to have sex as “frequently as possible” is actually going to have the desired effect, particularly in light of the busy lives that many people lead.

Is the pressure of having frequent sex getting in the way of happiness?

Dr. Muise reports a clear relationship between the frequency of sex and happiness. What she found was that people who had sex once per week or more often were significantly happier than those who had sex less often.

But study participants who had sex on several occasions per week were not happier than those who had sex once each week.

The results were true for individuals who were in a romantic relationship, including women, older participants, and those in long-term relationships who tend to have less sex.

Interestingly, having sex had a greater effect on the participants’ happiness than income. So if sex makes us happy, why do so many people lose interest?

Who loses interest in sex?

There is plenty of evidence that being in a long-term relationship, being a woman, and increasing age are linked to a drop in sexual frequency.

Last year, MNT reported that women’s sexual desire decreased in long-term relationships. However, over the 7-year study period, the participants’ ability to reach orgasm improved – especially in those who had been in the same relationship the entire time.

So, for women, staying with a partner means better orgasms but less interest in sex, according to the research.

Last week, we reported on a new study published in BMJ Open that adds to the body of evidence showing that women’s interest in sex decreases in relationships.

Prof. Cynthia Graham, from the Centre for Sexual Health Research at the University of Southampton in the United Kingdom, found that more than 34 percent of women who had lived with their partner for at least 1 year lacked interest in sex, while only 15 percent of men did.

The biggest turn-offs

Prof. Graham identified a number of factors that were associated with the drop in sexual desire found in her study.

For women, these were having young children, having been pregnant in the past year, living with their partner, being in a longer relationship, not sharing the same level of sexual interest, and not sharing the same sexual preferences.

For both genders, health conditions (including depression), not feeling close to their partner during sex, being less happy with their relationship, and having sex less often than they were interested in all contributed to a drop in sexual interest.

Age was another factor. Men experienced the lowest levels of interest in sex between the ages of 35 and 44, while for women, this was between 55 and 64.

Julia Velten, Ph.D. – a postdoctoral fellow at the Mental Health Research and Treatment Center at Ruhr University Bochum in Germany – reported that when men felt that their partner expected them to always initiate sex, it had a negative effect on their sexual satisfaction.

Sexual desire discrepancy, which is the difference between the actual and desired frequency of sex, was a negative factor for both men and women.

Sexual function also played a role for the couples in Dr. Velten’s study. Men were affected by their partner’s lack of sexual function, such as lack of arousal, while women were more affected by the partner’s distress about their own sexual problem, such as erectile dysfunction.

How does masturbation fit into the picture?

On this topic, research findings do not agree. In a study involving couples living in Prague, Kateřina Klapilová, Ph.D. – from the Department of General Anthropology at Charles University in Prague – found that for women, masturbation negatively affected their sexual satisfaction.

But masturbation had no effect on men in these couples.

Meanwhile, Prof. Graham found that men who had recently masturbated were less interested in sex, while masturbation was not related to a change in women’s sex drive.

Prof. Graham told MNT that in her previous research, she had “found striking gender differences in factors associated with frequency of masturbation in men and women.”

She added that “when men were having less partnered sex, they tended to masturbate more often, whereas the reverse was true for women.”

With 51.7 percent of male and 17.8 percent of female participants reporting to have masturbated in the 7 days prior to study interviews, this is clearly a factor that is important in many relationships.

But just how masturbation contributes to or distracts from long-term sexual satisfaction remains to be seen.

With significant levels of both men and women reporting a drop in sexual interest and satisfaction, is there a secret to keeping the spark alive?

The secret to sexual satisfaction

Dr. Klapilová’s study found that for both men and women, penile-vaginal intercourse and the consistency of being able to reach vaginal orgasm were associated with sexual satisfaction.

She points to the “special role that vaginal orgasm (as distinct from other orgasm triggers) had in maintaining higher-quality intimate relationships.”

Anik Debrot, Ph.D. – alongside Dr. Muise and other colleagues from the University of Toronto Mississauga – recently studied the link between affection and sexual activity.

In her study paper, which was published this year in the journal Personality and Social Psychology Bulletin, she explains that “when engaging in sex, people not only seek an intimate connection, but indeed experience more affection, both when having sex and in the next several hours.”

“Thus, sex within romantic relationships provides a meaningful way for people to experience a strong connection with their partner,” she adds.

To her, this indicates that sex is important in romantic relationships because of the emotional benefits that we feel. Dr. Debrot suggests, “[When sex may be impaired], affection could help maintain well-being despite decreased sex frequency.”

The effect of time

A study by Prof. Julia Heiman, from the Department of Psychological & Brain Sciences at Indiana University in Bloomington, studied 1,000 couples in five countries (Brazil, Germany, Japan, Spain, and the United States).

Although the length of the couples’ relationships ranged from 1 to 51 years, half had been together for at least 25 years.

Prof. Heiman found that “[w]omen reported significantly more sexual satisfaction than men and men more relationship satisfaction.” In particular, “Men who valued their partner’s orgasm were more likely to report relationship happiness.”

Women’s sexual satisfaction increased from 40 percent at the start of the relationship to 86 percent once they had been with their partner for 40 years.

From these studies, penile-vaginal sex, affection, and the time spent in the relationship are key ingredients to a happy sex life. But there is one more factor that could be key: open communication.

Talking about sex

In Dr. Velten’s study, open communication about sexual wishes and frequencies had a positive effect on the quality of sex that the participants reported.

Likewise, participants in Prof. Graham’s study who found it easy to talk about sex with their partner were more interested in sex.

She told MNT that “[their] findings underline that open communication with a partner about sex is one of the most important things you can do to try to maintain sexual interest in a relationship.”

Sexual desires and preferences are, by nature, intrinsically personal and individual. Research in this field is complex, and while studies can show associations and trends, they will not be able to tease apart the reasons for an individual’s sexual satisfaction.

I don’t think that there is any ‘secret’ to long-term sexual satisfaction! Human sexuality is too diverse and ‘fluid’ for this to be the case – but […] open communication about sex with a partner should go some way to preventing sexual problems from developing.”

Prof. Cynthia Graham

Talking about sex may be a good starting point. Finding a way to fit sex into the pressures of daily life may be challenging, but affection and time together might well help.

September 22, 2017 at 12:15PM

September Is National Family Meals Month

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tips for doing it allNow in its third year, Family Meals Month is intended to encourage people to set aside time at least a few days a week to convene the family around a home-cooked meal. Research has concluded time and again that when families eat together, the kids are happier and get better grades, the family is more cohesive and emotionally close, everyone eats better and both the family’s health and the family’s budget benefit. A 2010 study at Columbia University found that teenagers who frequently ate with their families tended to use drugs less often. Another study, this one at Cornell, showed that children who eat family dinners had fewer signs of depression. So why don’t people do it as often as they’d like to?

Often, parents tell me it’s that they just don’t have time. There is so much that can get in the way. The adults have jobs, family obligations (like elder care), volunteer or political work, time at the gym and maintaining connection with their partner and a social life. Grocery shopping, chores, home maintenance and childcare have to be done. Most kids have homework and are involved in sports and activities. Teens are navigating the complicated social scene and starting to date. And a new challenge is the pull, and distraction, of technology. It feels impossible to get everyone together at the same time around the same table, much less to prepare a wholesome meal.

The result? A recent study by the Toluna group shows that nearly half (47%) of parents say that they share fewer meals with their family than when they were growing up. And yet that same Toluna study shows that 78% of families see having dinner together as a priority. The good news is that nearly all (99%) of the families surveyed reported that they have at least one meal together as a family a week. And four in five (85%) typically have dinner together as a family four or more nights each week (accounting for more than half the dinners each week). The issue for most of these families is not that they are never having meals together but rather that they’d like to do it more often.

To pull it off, many parents need to rethink the idea that there isn’t “time”. It’s probably not that there isn’t time. It’s more likely that they need to look at how they are choosing to use it that determines whether there is “time” for more dinners at home with the family

Consider this: There are 168 hours in every week. A mealtime together, from prep time to clean up, may take less than an hour and a half. It’s up to each of us as parents, to think about how we can manage to sit down as a family for, say, 4 meals a week. That’s 1.5 hours x 4 dinners = 6 hours total out of your week. If you want to have dinner together on 5 nights, it only adds up to 7.5 hours of your week devoted to family meals. Only you can decide if it is worth 6 – 7 ½ hours a week for family health, happiness and togetherness! Only you can determine if you can squeeze another hour and a half a week out of your collective schedules to have an additional mealtime together.

7 Ways to Increase Family Dinner Times

If you would like to increase the number of times a week that your family eats dinner together, it might be helpful to consider these tips:

  1. Make sure the adults agree: These days, more and more young parents did not themselves grow up with regular family mealtimes. If you and your partner do not agree about how many times a week it is important to convene the family around a pleasant meal, it will be almost impossible to make it happen. Start with a conversation about the benefits of family meals and come to a clear and mutual decision about how often you will establish a family dinner time.
  2. Schedule family meal times. Make eating together a priority instead of something that will happen only if everyone happens to be around. If everyone knows, for example, that family meals happen on Monday, Tuesday, Wednesday and Thursday at 6:00 and Sunday at 5:00, other activities will be scheduled around them – at least most of the time.
  3. Be flexible. Sometimes parents have to work late for a special project or work an evening shift. Sometimes kids’ sports practices or other activities will compete with your preferred meal time. Get creative: You can set an earlier dinner so everyone can be there. A healthy snack in the afternoon can make it possible for dinner to happen later. Yes. Sometimes it’s all we can do to let everyone graze out of the slow cooker to accommodate competing schedules and to get everyone fed. Just don’t lose sight of the goal to bring the family together regularly to share food and conversation.
  4. Include everyone in planning. When everyone in a household (particularly teens) are involved in planning, they have a greater stake in the plans. Periodically review with the entire family what is practical and manageable as a family meal time schedule.
  5. Focus on the time, not the dinner. Remember that take out now and then or meals that can be thrown together in 15 minutes can still be nutritious, budget-friendly and sufficient for a family mealtime. If you really love to cook gourmet meals, do it — but preferably with the kids. Kids who cook with their parents are less likely to be picky eaters and more likely to stick around for the meal. Prepping food together can be as much a bonding experience as eating it.
  6. Ban technology at the table. If mealtimes are important to family bonding, each member needs to be truly present and not distracted by a phone, the TV or a tablet. Children learn the art of conversation by listening and talking. If you are out of practice yourself, find some discussion starters or word games on the internet to jump start family talk. Do spend a few minutes letting each member of the family share their day.
  7. Keep meal times happy. Dinner time is not the time to scold, nag, complain or discipline. It’s a time to set aside all that and focus on the positive aspects of being a family. Be interested in what interests the kids. Expand their world by including them in discussions about community and world events. Share jokes and stories. When people have a good time, they’ll want to do it more often.

September 22, 2017 at 11:51AM

Jellyfish Caught Snoozing Give Clues to Origin of Sleep

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The purpose and evolutionary origins of sleep are among the biggest mysteries in neuroscience. Every complex animal, from the humblest fruit fly to the largest blue whale, sleeps—yet scientists can’t explain why any organism would leave itself vulnerable to predators, and unable to eat or mate, for a large portion of the day. Now, researchers have demonstrated for the first time that even an organism without a brain—a kind of jellyfish—shows sleep-like behaviour, suggesting that the origins of sleep are more primitive than thought.

Researchers observed that the rate at which Cassiopea jellyfish pulsed their bell decreased by one-third at night, and the animals were much slower to respond to external stimuli such as food or movement during that time. When deprived of their night-time rest, the jellies were less active the next day.

“Everyone we talk to has an opinion about whether or not jellyfish sleep. It really forces them to grapple with the question of what sleep is,” says Ravi Nath, the paper’s first author and a molecular geneticist at the California Institute of Technology (Caltech) in Pasadena. The study was published on 21 September in Current Biology.

“This work provides compelling evidence for how early in evolution a sleep-like state evolved,” says Dion Dickman, a neuroscientist at the University of Southern California in Los Angeles.

Mindless sleep

Nath is studying sleep in the worm Caenorhabditis elegans, but whenever he presented his work at research conferences, other scientists scoffed at the idea that such a simple animal could sleep. The question got Nath thinking: how minimal can an animal’s nervous system get before the creature lacks the ability to sleep? Nath’s obsession soon infected his friends and fellow Caltech PhD students Michael Abrams and Claire Bedbrook. Abrams works on jellyfish, and he suggested that one of these creatures would be a suitable model organism, because jellies have neurons but no central nervous system. Instead, their neurons connect in a decentralized neural net.

Cassiopea jellyfish, in particular, caught the trio’s attention. Nicknamed the upside-down jellyfish because of its habit of sitting on the sea floor on its bell, with its tentacles waving upwards, Cassiopea rarely moves on its own. This made it easier for the researchers to design an automated system that used video to track the activity of the pulsing bell. To provide evidence of sleep-like behaviour in Cassiopea (or any other organism), the researchers needed to show a rapidly reversible period of decreased activity, or quiescence, with decreased responsiveness to stimuli. The behaviour also had to be driven by a need to sleep that increased the longer the jellyfish was awake, so that a day of reduced sleep would be followed by increased rest.

Other researchers had already documented a nightly drop in activity in other species of jellyfish, but no jellyfish had been known to display the other aspects of sleep behaviour. In a 35-litre tank, Nath, Abrams and Bedbrook tracked the bell pulses of Cassiopea over six days and nights and found that the rate, which was an average of one pulse per second by day, dropped by almost one-third at night. They also documented night-time pulse-free periods of 10–15 seconds, which didn’t occur during the day.

Restless night

Without an established jellyfish alarm clock, the scientists used a snack of brine shrimp and oyster roe to try to rouse the snoozing Cassiopea. When they dropped food in the tank at night, Cassiopea responded to its treat by returning to a daytime pattern of activity. The team used the jellyfish’s preference for sitting on solid surfaces to test whether quiescent Cassiopea had a delayed response to external stimuli. They slowly lifted the jellyfish off the bottom of the tank using a screen, then pulled it out from under the animal, leaving the jelly floating in the water. It took longer for the creature to begin pulsing and to reorient itself when this happened at night than it did during the day. If the experiment was immediately repeated at night, the jellyfish responded as if it were daytime. Lastly, when the team forced Cassiopea to pull an all-nighter by keeping it awake with repeated pulses of water, they found a 17% drop in activity the following day.

“This work shows that sleep is much older than we thought. The simplicity of these organisms is a door opener to understand why sleep evolved and what it does,” says Thomas Bosch, an evolutionary biologist at Kiel University in Germany. “Sleep can be traced back to these little metazoans—how much further does it go?” he asks.

That’s what Nath, Abrams and Bedbrook want to find out. Amid the chaos of finishing their PhD theses, they have begun searching for ancient genes that might control sleep, in the hope that this might provide hints as to why sleep originally evolved.

This article is reproduced with permission and was first published on September 21, 2017.

September 22, 2017 at 09:47AM