What are the risks of post-traumatic stress disorder after an accident?

Many patients continue to suffer from symptoms (headaches, pain) several months after an accident, which can pose a real handicap to their lives. The team of Emmanuel Lagarde, research director at Inserm’s Research Centre for Epidemiology and Biostatistics (Inserm/University of Bordeaux) has studied the subsequent development of 1,300 people who were admitted to A&R between 2007 and 2009 for trauma. The researchers demonstrate that it is possible to identify people who will develop post-traumatic stress disorder, which generally occurs when the individual’s life was put in danger. This will enable their care to be adjusted accordingly. Their work also reveals that post-concussion syndrome, which has wrongly been defined as the consequence of cranial trauma, is only one part of post-traumatic stress disorder.

The results of the study have been published in the journal JAMA Psychiatry.

Every year, one in ten people in France are taken to A&E with a trauma following an accident. The large majority of the victims have only mild injuries and are discharged from hospital quickly. However, a number of them continue to suffer long after their direct injuries have healed. They may, for example, have headaches, uncontrollable fear or maladies of various kinds, vision problems, balancing problems or be irritable. When the symptoms occur simultaneously in a single context, they constitute what is called a syndrome.

Following a trauma, two syndromes are described: post-concussion syndrome (PCS), which occurs after a mild cranial trauma, and post-traumatic stress disorder (PTSD), which is encountered in people who have been exposed to a stressful situation wherein their life, or that of another person, was put in danger. Post-traumatic stress disorder was initially described in soldiers who, after exposure to combat or an explosion, complain of nightmares or obsessive thoughts which they are unable to get rid of. The two syndromes have been described for several years in the successive editions of the Diagnostic and Statistical Manual of Mental Disorders (DSM) of the American Psychiatric Association, which is a current standard reference in the area of diagnosis in mental health.

In this study, 1,300 people who were admitted to A&E at the Bordeaux Hospital Centre between 2007 and 2009 were contacted three months after their accident. Over 500 were suffering from a mild cranial trauma when they were admitted to hospital while the others had various injuries, all either mild or moderate in severity. The researchers measured the occurrence of 36 symptoms which are included in the definitions of PCS and PTSD.

‘Post-concussion syndrome (PCS) does not deserve its name because, on the one hand, the symptoms that constitute it are not specific to cranial trauma and, on the other, they do not occur simultaneously. It seems that PCS is, in reality, only one part of post-traumatic stress disorder’, explained Emmanuel Lagarde, research director at Inserm.

Post-traumatic stress disorder in the general population

The results obtained also make it possible to have a better understanding of post-traumatic stress disorder, which is still insufficiently described for non-military contexts. In the general population, this disorder occurs in 2% of injured people but this figure rises to 9% when the trauma is cranial. However, it is more frequent among women and people who have been in a road accident or have been attacked. The occurrence of PTSD is also influenced by the state of the victim’s physical and mental health before the accident. All this information can enable doctors to determine if early treatment should be provided.

This study puts the classification of post-traumatic complaints into question because it also questions the very existence of post-concussion syndrome, which should be seen as only one part of post-traumatic stress disorder. These results do not, however, question the reality of the suffering of a significant number of people affected by this disorder, for whom the symptoms continue to persist and considerably impact the quality of their lives.

‘This is why it is necessary to describe these syndromes and their origin more accurately, particularly because identifying them also has important consequences in terms of insurance, compensation and the care and rehabilitation policies of patients’, stressed Emmanuel Lagarde, who is the main author of this work.

Measuring Nurture: Study Shows How “Good Mothering” Hardwires Infant Brain

By carefully watching nearly a hundred hours of video showing mother rats protecting, warming, and feeding their young pups, and then matching up what they saw to real-time electrical readings from the pups’ brains, researchers at NYU Langone Medical Center have found that the mother’s presence and social interactions — her nurturing role — directly molds the early neural activity and growth of her offsprings’ brain.

Reporting in the July 21 edition of the journal Current Biology, the NYU Langone team showed that the mother’s presence in the nest regulated and controlled electrical signaling in the infant pup’s brain.

Although scientists have known for decades that maternal-infant bonding affects neural development, the NYU Langone team’s latest findings are believed to be the first to show — as it is happening — how such natural, early maternal attachment behaviors, including nesting, nursing, and grooming of pups, impact key stages in postnatal brain development.

Researchers say the so-called slow-wave, neural signaling patterns seen during the initial phases of mammalian brain development — between age 12 and 20 days in rats — closely resembled the electrical patterns seen in humans for meditation and conscious and unconscious sleep-wake cycles, and during highly focused attention. These early stages are when permanent neural communication pathways are known to form in the infant brain, and when increasing numbers of nerve axons become sheathed, or myelinated, to speed neural signaling.

According to senior study investigator and neurobiologist Regina Sullivan, PhD, whose previous research in animals showed how maternal interactions influenced gene activity in the infant brain, the latest study offers an even more profound perspective on maternal caregiving.

“Our research shows how in mammals the mother’s sensory stimulation helps sculpt and mold the infant’s growing brain and helps define the role played by ‘nurturing’ in healthy brain development, and offers overall greater insight into what constitutes good mothering,” says Sullivan, a professor at the NYU School of Medicine and its affiliated Nathan S. Kline Institute for Psychiatric Research. “The study also helps explain how differences in the way mothers nurture their young could account, in part, for the wide variation in infant behavior among animals, including people, with similar backgrounds, or in uniform, tightly knit cultures.”

“There are so many factors that go into rearing children,” says lead study investigator Emma Sarro, PhD, a postdoctoral research fellow at NYU Langone. “Our findings will help scientists and clinicians better understand the whole-brain implications of quality interactions and bonding between mothers and infants so closely after birth, and how these biological attachment behaviors frame the brain’s hard wiring.”

For the study, a half-dozen rat mothers and their litters, of usually a dozen pups, were watched and videotaped from infancy for preset times during the day as they naturally developed. One pup from each litter was outfitted with a miniature wireless transmitter, invisibly placed under the skin and next to the brain to record its electrical patterns.

Specifically, study results showed that when rat mothers left their pups alone in the nest, infant cortical brain electrical activity, measured as local field potentials, jumped 50 percent to 100 percent, and brain wave patterns became more erratic, or desynchronous. Researchers point out that such periodic desynchronization is key to healthy brain growth and communication across different brain regions.

During nursing, infant rat pups calmed down after attaching themselves to their mother’s nipple. Brain activity also slowed and became more synchronous, with clearly identifiable electrical patterns.

Slow-wave infant brain activity increased by 30 percent, while readings of higher brain-wave frequencies decreased by 30 percent. Milk delivery led to intermittent bursts of electrical brain activity that were double or five times higher than before.

Similar spikes in rat brain activity of more than 100 percent were observed when mothers naturally groomed their infant pups.

However, these brain surges progressively declined during weaning, as infant pups gained independence from their mothers, leaving the nest and seeking food on their own as they grew past two weeks of age.

Additional experiments with a neural-signaling blocking agent, propranolol, confirmed that maternal effects were controlled in part by secretion of norepinephrine, a key neurotransmitter and hormone involved in most basic brain and body functions, including regulation of heart rate and cognition. Noradrenergic blocking in infant rats mostly dampened all previously observed effects induced by their mothers.

Sullivan says her team next plans similar experiments to look at how behavioral variations by the mother affect infant rat brain development, with the added goal of mapping any differences in brain development.

Long term, they say, they hope to develop diagnostic tools and therapies for people whose brains may have been impaired or simply underdeveloped during infancy.

Sarro says more research is also under way to investigate what other, nonadrenergic biological mechanisms might also be involved in controlling maternal sensory stimulation of the infant brain.

Eye movements reveal difference between love and lust

Soul singer Betty Everett once proclaimed, “If you want to know if he loves you so, it’s in his kiss.” But a new study by University of Chicago researchers suggests the difference between love and lust might be in the eyes after all.

Specifically, where your date looks at you could indicate whether love or lust is in the cards. The new study found that eye patterns concentrate on a stranger’s face if the viewer sees that person as a potential partner in romantic love, but the viewer gazes more at the other person’s body if he or she is feeling sexual desire. That automatic judgment can occur in as little as half a second, producing different gaze patterns.

“Although little is currently known about the science of love at first sight or how people fall in love, these patterns of response provide the first clues regarding how automatic attentional processes, such as eye gaze, may differentiate feelings of love from feelings of desire toward strangers,” noted lead author Stephanie Cacioppo, director of the UChicago High-Performance Electrical NeuroImaging Laboratory. Cacioppo co-authored the report, now published online in the journal Psychological Science, with colleagues from UChicago’s Departments of Psychiatry and Psychology, and the University of Geneva.

Previous research by Cacioppo has shown that different networks of brain regions are activated by love and sexual desire. In this study, the team performed two experiments to test visual patterns in an effort to assess two different emotional and cognitive states that are often difficult to disentangle from one another—romantic love and sexual desire (lust).

Male and female students from the University of Geneva viewed a series of black-and-white photographs of persons they had never met. In part one of the study, participants viewed photos of young, adult heterosexual couples who were looking at or interacting with each other. In part two, participants viewed photographs of attractive individuals of the opposite sex who were looking directly at the camera/viewer. None of the photos contained nudity or erotic images.

In both experiments, participants were placed before a computer and asked to look at different blocks of photographs and decide as rapidly and precisely as possible whether they perceived each photograph or the persons in the photograph as eliciting feelings of sexual desire or romantic love. The study found no significant difference in the time it took subjects to identify romantic love versus sexual desire, which shows how quickly the brain can process both emotions, the researchers believe.

But analysis of the eye-tracking data from the two studies revealed marked differences in eye movement patterns, depending on whether the subjects reported feeling sexual desire or romantic love. People tended to visually fixate on the face, especially when they said an image elicited a feeling of romantic love. However, with images that evoked sexual desire, the subjects’ eyes moved from the face to fixate on the rest of the body. The effect was found for male and female participants.

“By identifying eye patterns that are specific to love-related stimuli, the study may contribute to the development of a biomarker that differentiates feelings of romantic love versus sexual desire,” said co-author John Cacioppo, the Tiffany and Margaret Blake Distinguished Service Professor and director of the Center for Cognitive and Social Neuroscience. “An eye-tracking paradigm may eventually offer a new avenue of diagnosis in clinicians’ daily practice or for routine clinical exams in psychiatry and/or couple therapy.”

The Mediterranean Diet Has Varied Effects on Cognitive Decline Among Different Race-Specific Populations

While the Mediterranean diet may have broad health benefits, its impact on cognitive decline differs among race-specific populations, according to a new study published in the Journal of Gerontology.

The team of researchers, including Ben-Gurion University of the Negev (BGU Prof. Danit R. Shahar RD, Ph.D, analyzed an NIH/NIA prospective cohort study [Health ABC] conducted over eight years in the U.S. to measure the effects of adherence to a Mediterranean diet. Prof. Shahar is affiliated with the BGU S. Daniel Abraham International Center for Health and Nutrition, Department of Public Health, Faculty of Health Sciences.

The Mediterranean-style diet (MedDiet) has fewer meat products and more plant-based foods and monounsaturated fatty acids from olive and canola oil (good) than a typical American diet.

To assess the association between MedDiet score and brain function, the researchers used data of several Modified Mini-Mental State Examinations (3MS) on 2,326 participating older adults (70-79). The 3MS is an extensively used and validated instrument designed to measure several cognitive domains to screen for cognitive impairment and commonly used to screen for dementia.

"In a population of initially well-functioning older adults, we found a significant correlation between strong adherence to the Mediterranean diet and a slower rate of cognitive decline among African American, but not white, older adults. Our study is the first to show a possible race-specific association between the Mediterranean diet and cognitive decline.”

The researchers note that further studies in diverse populations are necessary to confirm association between the MedDiet and cognitive decline, and to pinpoint factors that may explain these results.

(Image: Getty Images)

(Image caption: Whole brain functional connectivity between the nucleus accumbens (NAc) and other brain areas in response to cannabis cues (vs. neutral cues) in all participants)

Dependence Alters the Brain’s Response to Pot Paraphernalia

New research from The University of Texas at Dallas demonstrates that drug paraphernalia triggers the reward areas of the brain differently in dependent and non-dependent marijuana users.

The study, published July 1 in Drug and Alcohol Dependence, demonstrated that different areas of the brain activated when dependent and non-dependent users were exposed to drug-related cues.

The 2012 National Survey on Drug Use and Health shows marijuana is the most widely used illicit drug in the United States. According to a 2013 survey from the Pew Research Center, 48 percent of Americans ages 18 and older have tried marijuana. The National Institute on Drug Abuse says that 9 percent of daily users will become dependent on marijuana.

“We know that people have a hard time staying abstinent because seeing cues for the drug use triggers this intense desire to seek out the drugs,” said Dr. Francesca Filbey, lead author of the study and professor at the Center for BrainHealth in the School of Behavioral and Brain Sciences. “That’s a clinically validated phenomenon and behavioral studies have also shown this to be the case. What we didn’t know was what was driving those effects in the brain.”

To find this effect, Filbey and colleagues conducted brain-imaging scans, called functional magnetic resonance imaging (fMRI), on 71 participants who regularly used marijuana. Just more than half of those were classified as dependent users. While being scanned, the participants were given either a used marijuana pipe or a pencil of approximately the same size that they could see and feel.

A comparison of the images revealed that the nucleus accumbens, the reward region in the brain, was activated in all users in response to the pipe. However, the strengths of the connections with other areas differed between dependent and non-dependent users.

“We found that the reward network is actually being driven by other areas unrelated to reward, like the areas in memory and attention or emotion,” Filbey said.

Non-dependent users showed greater activations in the orbital frontal cortex and hippocampus, suggesting that memory and attention were connected to the activation of the reward network. Dependent users had greater activations in the amygdala and anterior cingulate gyrus, suggesting a more emotional connection.

Additionally, the areas of the brain activated resemble areas activated for other addictions, such as nicotine or cocaine, lending greater support to the addictiveness of marijuana.

These findings suggest that marijuana abuse intervention needs to cater more specifically to a user’s level of addiction.

"Clinicians treating people with problems with marijuana dependence should consider the different processes that trigger the reward response when determining possible pharmacological or behavioral interventions,” Filbey said.

Brain of World’s First Known Predators Discovered

An international team of paleontologists has identified the exquisitely preserved brain in the fossil of one of the world’s first known predators that lived in the Lower Cambrian, about 520 million years ago. The discovery revealed a brain that is surprisingly simple and less complex than those known from fossils of some of the animal’s prey.

The find for the first time identifies the fossilized brain of what are considered the top predators of their time, a group of animals known as anomalocaridids, which translates to “abnormal shrimp.” Long extinct, these fierce-looking arthropods were first discovered as fossils in the late 19th century but not properly identified until the early 1980s. They still have scientists arguing over where they belong in the tree of life.

"Our discovery helps to clarify this debate," said Nicholas Strausfeld, director of the University of Arizona’s Center for Insect Science. "It turns out the top predator of the Cambrian had a brain that was much less complex than that of some of its possible prey and that looked surprisingly similar to a modern group of rather modest worm-like animals."

Strausfeld, a Regents’ Professor in the Department of Neuroscience in the UA College of Science, is senior author on a paper about the findings, which appear in the July 17 issue of Nature.

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