Category: Behavior

In a time of shrinking budgets, one University of Missouri professor believes that the current approach to juvenile crime is much too expensive to continue — and he has the numbers to prove it.

Charles Borduin, a professor of psychological sciences in the MU College of Arts and Science finds that multisystemic therapy (MST) is more effective in the lives of troubled youth and costs less.

Borduin has pioneered the model for the treatment and prevention of serious mental health problems in children and adolescents throughout the course of his career. MST interventions involve the offender's entire family and community, as opposed to the current method of individual therapy, where the offender visits a therapist who offers feedback, support and encouragement for behavior change.

With the assistance of Steve Aos from the Washington State Institute for Public Policy and Stephanie Klietz, a psychological science graduate student, Borduin formulated a cost-benefit analysis based on 176 juvenile offenders. With factors such as re-arrest costs and for resources such as law enforcement and correctional facilities, Borduin found that MST cost nearly 10 times less than the current system.

"We wanted to know, what does MST save taxpayers and crime victims? We have demonstrated that the net cumulative benefit of providing MST to a single juvenile offender resulted in a savings of $75,110 to $199,374 throughout the course of almost 14 years," Borduin said. "To put it another way, $1 spent on MST provides $9.51 to $23.59 in savings to taxpayers and crime victims in the years ahead."

Borduin readily admits that MST is initially more expensive because of the extent of the therapy that takes place in the home, schools and community. MST works because the therapy takes into account different environmental causes for behavior, and as a result, participants are half as likely to be arrested again. The numbers are so convincing that the country of Norway has adopted the practice, and states like Ohio, Colorado, Connecticut and Pennsylvania are reforming their systems, according to Borduin.

"Most current treatments are based on the idea that the problem lies entirely within the child," Borduin said. "If you look at the scientific literature, it's not about the individual kid — it's about family problems, low household warmth, high levels of conflict, abuse, neglect, involvement with the wrong group of kids, school problems, and so on. The way we approach violent juvenile crime now is similar to taking a car with a noisy motor to a mechanic, and the mechanic just changes the tires. The sad part is that the vast majority of current treatments are not effective while being very costly."

Borduin hopes that by addressing the problem in monetary terms, he can influence decision-makers and ultimately help more children.

"As widely disseminated as MST is, it's only reaching a fraction of the kids who need it," Borduin said. "I'm sure there are people who are saying 'We're doing the best we can,' but are we really? The monetary costs and the re-arrest statistics don't lie."

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Journal Reference:

1. Stephanie J. Klietz, Charles M. Borduin, Cindy M. Schaeffer. Cost–benefit analysis of multisystemic therapy with serious and violent juvenile offenders. Journal of Family Psychology, 2010; 24 (5): 657 DOI: 10.1037/a0020838

People diagnosed as psychopathic have difficulty showing empathy, just like patients who have suffered frontal head injury. This has been shown in a new study from the University of Haifa. "Our findings show that people who have psychopathic symptoms behave as though they are suffering frontal brain damage," said Dr. Simone Shamay-Tsoory, who conducted the study.

Psychopathy is a personality disorder that finds expression in extreme anti-social behavior and intentional harm to others, including a lack of compassion and empathy. An existing explanation for such behavior suggests inability to comprehend the existence of emotions in others. However, the fact that many psychopaths act with sophistication and deceit with intention to harm others, indicates that they actually have a good grasp of the mental capacity of others — and are even capable of using that knowledge in order to cause them harm.

Earlier research by Dr. Shamay-Tsoory has examined individuals with frontal head injury, i.e., damage to parts of the brain that are responsible for emotional functioning. She has shown that people suffering this type of brain damage have difficulty showing empathy. Having observed similar emotional deficiency in psychopathic behavior, she set out to see if there is in fact a similarity between the two cases.

The current study assessed 17 people who had been diagnosed by psychiatrists as psychopathic — and not suffering from any known brain damage; and another 25 individuals suffering frontal lobe injury. Each of the participants underwent a computerized test examining cognitive ability to recognize feelings in another and the ability to demonstrate empathy for another's emotions. They were also tested to gage their capacity to understand another's thoughts. The results of these tests showed that both groups demonstrated a similar difficulty in showing empathy, while two control groups of individuals with no known mental disorders or brain damage and individuals with non-frontal brain damage both showed different results with positive empathy capabilities.

"Seeing as psychopathic behavior is similar to that of a person with brain damage, it could be that it could benefit from similar forms of treatment," Dr. Shamay-Tsoory noted.

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Journal References:

1. Simone G. Shamay-Tsoory, Hagai Harari, Judith Aharon-Peretz, Yechiel Levkovitz. The role of the orbitofrontal cortex in affective theory of mind deficits in criminal offenders with psychopathic tendencies. Cortex, 2010; 46 (5): 668 DOI: 10.1016/j.cortex.2009.04.008
2. S. G. Shamay-Tsoory. The Neural Bases for Empathy. The Neuroscientist, 2010; DOI: 10.1177/1073858410379268

— Intensive early education programs for low-income children have been shown to yield numerous educational benefits, but few studies have looked more broadly at their impact on health and health behaviors. A new study conducted by researchers at Columbia University's Mailman School of Public Health examines this issue, using data from a the well-known Carolina Abecedarian Project (ABC), a randomized control study that enrolled 111 infants in the 1970s and continued to follow them through age 21.

Researchers found that individuals who had received the intensive education intervention starting in infancy had significantly better health and better health behaviors as young adults.

The study is only the second to explore the relationship of early childhood education and adult health benefits. The first study, based on the Perry Preschool Program, also was conducted by Columbia professors Peter Muennig, MD, and Matthew Neidell, PhD, on a similarly small cohort of children, and found behavioral benefits, but no overall health benefits. The current study is the first randomized control study to definitively show the health benefit of education.

Findings are online in the American Journal of Public Health.

The original study enrolled infants from 1972 to 1977 at the Frank Porter Graham Child Development Institute in Chapel Hill, NC, where they received an age-appropriate curriculum designed to enhance cognition and language development starting in infancy. Researchers had found that infants enrolled in the program had higher IQ by age three and higher reading and math achievement by 15 years of age, lower rates of teen depression and greater likelihood of college enrollment compared with a control group.

The current study expands on the original study to examine the impact of ABC on three health measures and 11 measures of behavioral risk factors. The health measures were the number of self-reported health problems since 15 years of age, a depression index score, and the number of hospitalizations in the past year. Behavioral risk factors concerned traffic safety, drug use, and access to primary care. Researchers found that participants had significantly better health and health behaviors and that these findings were independent of IQ, educational attainment or health insurance status.

The original study was small, but it had a very strong effect on education. Until it came along, the benefit of education had never been proven using the gold standard in research methods-the randomized controlled trial. What we have found is that this educational intervention also reduced health risks like smoking and improved health outcomes as early as age 21," said Dr. Muennig, assistant professor of Health Policy and Management at Columbia's Mailman School and principal investigator of the new study. "The health benefits were quite dramatic."

"While much remains to be learned about both the pathways linking education to health and the overall effect sizes of education on health, our study provides causal evidence in support of the hypothesis that early education enhancements may improve income, reduce crime, and even enhance the global competitiveness of the American workforce," suggests Dr. Muennig. "These interventions may be more cost effective than many traditional medical and public health approaches to improving population health.

— Biologists at Texas A&M University have made an important step toward understanding human mating behavior by showing that certain genes become activated in fruit flies when they interact with the opposite sex.

Their research, published in the January 2011 issue of the journal Genetics, shows that courtship behaviors may be far more influenced by genetics than previously thought. In addition, this new understanding as to why and how these genes become activated within social contexts may also lead to insight into disorders such as autism.

"Be careful who you interact with," said Dr. Ginger E. Carney, associate professor of biology and co-author of the study. "The choice may affect your physiology, behavior and health in unexpected ways."

To make this discovery, Carney and a student in her laboratory, Lisa L. Ellis, compared gene expression profiles in males that courted females, males that interacted with other males and males that did not interact with other flies. The investigators identified a common set of genes that respond to the presence of either sex. They also discovered that there are other genes which are only affected by being placed with members of a particular sex, either male or female. The researchers then tested mutant flies that were missing some of these socially responsive genes and confirmed that these particular genes are important for behavior.

Carney and Ellis predict that analyzing additional similar genes will give further insight into genes and neural signaling pathways that influence reproductive and other behavioral interactions.

"This study shows that we're closing in on the complex genetic machinery that affects social interactions," said Mark Johnston, editor-in-chief of Genetics. "Once similar genes are identified in humans, the implications will be enormous, as it could bring new understanding of, and perhaps even treatments for, a vast range of disorders related to social behavior."

Carney, who joined the Texas A&M Department of Biology faculty in 2004, earned her Ph.D. in genetics from the University of Georgia in 1998. She held positions as a postdoctoral researcher at Oregon State University (1998-2002) and as a faculty research scientist at Georgia Institute of Technology (2002-2004) prior to coming to Texas A&M, where her research focuses on the fruit fly Drosophila melanogaster and its genetic control of behavior and nervous system development.

Ellis earned her doctorate in biology from Texas A&M in August and now works as a research assistant in the Texas A&M Department of Entomology affiliated with Texas AgriLife Research.

Because fruit flies undergo many of the same developmental processes as larger creatures, including humans, Carney said they serve as model organisms, allowing researchers to observe details that can't necessarily be seen in more complex animals. Through this study and her future research, she hopes to learn more about how individual genes regulate behaviors from mating to central nervous system function in humans.

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Journal Reference:

1. L. L. Ellis, G. E. Carney. Socially-Responsive Gene Expression in Male Drosophila melanogaster Is Influenced by the Sex of the Interacting Partner. Genetics, 2010; 187 (1): 157 DOI: 10.1534/genetics.110.122754

 A new treatment program teaches people who suffer from panic disorder how to reduce the terrorizing symptoms by normalizing their breathing.

The method has proved better than traditional cognitive therapy at reducing both symptoms of panic and hyperventilation, according to a new study.

The biological-behavioral treatment program is called Capnometry-Assisted Respiratory Training, or CART, said psychologist and panic disorder expert Alicia E. Meuret at Southern Methodist University in Dallas.

CART helps patients learn to breathe in such a way as to reverse hyperventilation, a highly uncomfortable state where the blood stream operates with abnormally low levels of carbon dioxide, said Meuret, one of the researchers conducting the study.

Hyperventilation, a state of excessive breathing, results from deep or rapid breathing and is common in patients with panic disorders.

"We found that with CART it's the therapeutic change in carbon dioxide that changes the panic symptoms — and not vice versa," Meuret said.

CART: Breathing exercises twice a day

During the treatment, patients undergo simple breathing exercises twice a day. A portable capnometer device supplies feedback during the exercises on a patient's CO2 levels. The goal of these exercises is to reduce chronic and acute hyperventilation and associated physical symptoms. This is achieved by breathing slower but most importantly more shallowly. Contrary to lay belief, taking deep breaths actually worsens hyperventilation and symptoms.

"Most panic-disorder patients report they are terrified of physical symptoms such as shortness of breath or dizziness," Meuret said. "In our study, cognitive therapy didn't change respiratory physiology, but CART did effectively reduce hyperventilation. CART was proved an effective and powerful treatment that reduces the panic by means of normalizing respiratory physiology."

The findings, "Respiratory and cognitive mediators of treatment change in panic disorder: Evidence for intervention specificity," appeared in the Journal of Consulting and Clinical Psychology. Meuret, who developed CART, is an assistant professor in the Department of Psychology at SMU and co-directs the department's Stress, Anxiety and Chronic Disease Research Program. The Beth & Russell Siegelman Foundation funded the research.

CART breathing a proven biological therapy

The study pitted CART against a conventional cognitive therapy treatment, or CT. Traditional CT teaches patients techniques aimed at helping them change and reverse catastrophic thoughts in order to reduce fear and panic.

In the CART-CT study, 41 patients were assigned to complete either a CART or CT treatment program for panic disorder and agoraphobia, a fear of being trapped with no means of escape or help.

Both treatment programs were equally effective in reducing symptoms, said Meuret. But CART was the only treatment to physiologically alter panic symptoms by actively reversing hyperventilation in the patients. Cognitive therapy didn't change the respiratory physiology, said Meuret.

Treatment helps patients address terror associated with panic

The study is the second randomized control trial to measure CART's effectiveness. By reversing hyperventilation, patients reported a new ability to reduce panic symptoms by means of changing their respiration.

With CT, Meuret said, if a patient reports shortness of breath, the therapist challenges the assumption by asking how often the person actually has suffocated during a panic attack, then hopes that will reverse the patient's thinking.

"I found that process very challenging for some of my patients because it acknowledges the symptom but says it's not a problem," Meuret said.

"CART, however, tells us a patient's CO2 is very low and is causing many of the symptoms feared, but it can also show how to change these symptoms through correct breathing. There has been an assumption that if people worry less about symptoms it will also normalize their physiology, but this study shows that this is not the case," she said. "Hyperventilation remains unchanged, which could be a risk factor for relapse down the road. Apart from hyperventilation being a symptom generator, it is an unhealthy biological state associated with negative health outcomes."

Broader study planned to measure CART

The researchers plan to branch out with their studies on CART by taking the program into the community, particularly to ethnic minorities. They believe CART is a more universally understood treatment due to its physical exercises — as opposed to cognitive therapy's more intellectual methods — and therefore more accessible to a broader range of people with varying levels of education and different cultural backgrounds. Ongoing studies will test the efficacy of CART in patients with asthma and fear of blood.

Co-authors of the study at SMU were David Rosenfield, associate psychology professor, and psychology graduate students Anke Seidel and Lavanya Bhaskara. Stefan G. Hofmann, psychology professor at Boston University, was also an author on the paper.

Researchers from Mount Sinai School of Medicine have found that when one copy of the SHANK3 gene in mice is missing, nerve cells do not effectively communicate and do not show cellular properties associated with normal learning. This discovery may explain how mutations affecting SHANK3 may lead to autism spectrum disorders (ASDs).

The research is currently published in Molecular Autism.

"We know that SHANK3 mutation plays a central, causative role in some forms of autism spectrum disorders, but wanted to learn more about how it does this," said Joseph Buxbaum, PhD, Director of the Seaver Autism Center and Professor of Psychiatry, Neuroscience and Genetics and Genomic Sciences at Mount Sinai School of Medicine. "These data provide critical insight into the mechanism behind the development of the cognitive and social changes associated with autism."

Previous research has shown that gene mutation in SHANK3 is associated with delayed language abilities, learning disability, and ASDs. A team of researchers at the Seaver Autism Center for Research and Treatment at Mount Sinai School of Medicine and the Intramural Research Program of the National Institute of Mental Health wanted to better understand the connection between the SHANK3 mutation and subsequent brain and behavioral difficulties. They examined mice genetically engineered to lack one copy of SHANK3, similar to patients who have a mutation in one copy of SHANK3, and compared the nerve cell activity of these mice with that of mice in a control group that did not have the mutation. They also examined social behaviors in these mice.

Mount Sinai scientists looked at brain activity in vitro and worked with the NIMH Laboratory of Behavioral Neuroscience, led by Jacqueline Crawley, PhD, to evaluate behavioral differences in the two groups of mice. The research team observed impaired communication between nerve cells in the mice with the SHANK3 mutation. They also found altered functional and structural plasticity in nerve cells, which is a cellular measure of the flexibility that occurs during learning, and in the synapses — the points of contact between nerve cells. Behavioral observations indicated reduced male-female social interactions in the SHANK3 mutant mice. The studies identify clear brain targets that can implicate drugs that can be therapeutic.

"These results have helped us determine a pathological mechanism behind neurodevelopmental disorders like autism," said Dr. Buxbaum. "Currently, the only therapeutic options for people with ASDs are to treat the symptoms of the disease, like anxiety or aggression. Armed with this breakthrough, we can begin testing drug compounds that treat the disease at its root cause, improving nerve cell communication. We hope and expect that, like other developmental disorders such as Fragile X syndrome, the use of mouse models will lead directly to clinical trials that can benefit patients."

The study was supported by a grant from the Seaver Foundation and a special multi-site grant awarded to co-authors Drs. Buxbaum, Crawley, Hof and Zhou from the Simons Foundation.

Tinnitus — what many think of as "ringing in the ears" — is the perception of sound without any real acoustic stimulation. Sound masking therapy, a common component of tinnitus treatment, is of uncertain benefit when used on its own, a new evidence review finds.

Tinnitus sufferers might hear one sound or multiple ones; they can hear them continuously or intermittently. The sounds are imperceptible to others. For most people, the phantom sounds — hissing, whooshing and others — hardly matter.

But for a small minority, tinnitus causes severe problems, such as anxiety, insomnia and even major depression sometimes leading to suicide.

Jonathan Hobson, lead author of the new Cochrane review, said that sound therapy relies on distraction, with an additional noise — often called white noise — reducing the contrast between the patient's tinnitus signal and the background noise. This reduces the person's perception of the phantom sounds and the distress they cause.

Hobson and colleagues at the Centre for Hearing and Balance Studies at Bristol University, in England, summarized the results of six studies of 553 adults with persistent tinnitus who underwent sound therapy either alone or combined with other treatments.

People receive sound therapy in several ways: by devices worn in or on the ear, by headphones connected to an MP3-like device or with an under-the-pillow speaker for night use.

Sound masking rarely is a standalone therapy; other treatment methods usually accompany it. Tinnitus therapies include medications, psychological interventions such as cognitive behavioral therapy and holistic approaches such as acupuncture.

Most tinnitus sufferers are adults between about 50 and 70 years of age who also have diminished hearing. Accordingly, for most, hearing aids represent a first line of treatment, improving the hearing of actual external sounds and diminishing the phantom sounds at the same time.

The review was published by the Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.

"[The review] does not provide high-quality evidence that sound therapy devices are better than alternative treatments, but they are probably better than no treatment at all and certainly no harm or adverse effects have been reported with their use," Hobson said. "The six trials included were all very different in nature and compared sound therapy devices to a variety of other interventions: information, counseling, tinnitus retraining therapy, hearing aids or no treatment.

U.S. tinnitus expert, Robert Sweetow, Ph.D., views the use of sound therapy somewhat differently. He said that sound therapy, as used today, does not aim to mask tinnitus. "Rather, it is meant to mingle with the tinnitus and provide acoustic stimulation to the brain to help compensate for the lack of stimulation caused by hearing loss," he said.

Hobson said that one study did report that subjectively patients found the sound therapy devices to be useful with lower levels of 'tinnitus annoyance' with their use.

Sweetow, a professor of otolaryngology at the University of California, San Francisco, has treated patients and studied tinnitus for more than 30 years. He agreed with the reviewers that the weight of evidence does not support sound therapy as a primary treatment.

"Rather they, and I, would consider sound therapy to be adjunctive to counseling," Sweetow said. "The authors acknowledge this, stating that the studies they reviewed used a combination of approaches, making it impossible to properly delineate why effects occurred."

Sweetow also concurred with the authors that there are few good long-term studies supporting sound therapy. Still, he said, "I would not like to see the medical community conclude that sound therapy is not helpful on the basis of this analysis. Rather, I would conclude that sound therapy is useful only when combined with a counseling component to complete a therapeutic process."

"Hearing aids are a part of sound therapy and there is absolutely no doubt that they help most tinnitus patients." Sweetow added.

He cautioned review readers from concluding that there is no evidence in support of sound therapy: "There is simply no way one can, or should, separate sound therapy from counseling strategies since the ultimate goal must be habituation, or conscious suppression, rather than elimination of the tinnitus."

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Journal Reference:

1. Hobson J, Chisholm E, El Refaie A. Sound therapy (masking) in the management of tinnitus in adults (review). Cochrane Database of Systematic Reviews, 2010, Issue 12.

— Children exposed to Jalan Sesama, an Indonesian version of the children's television show Sesame Street, had improved educational skills and healthy development, according to a study by researchers at the Johns Hopkins Bloomberg School of Public Health. Over a 14-week period, the children who had the greatest exposure to Jalan Sesama improved significantly in literacy, mathematics, early cognitive skills, safety knowledge and social awareness, compared to those with no or low exposure to the program. The study is available online in advance of publication in the International Journal of Behavioral Development.

"I was amazed with how much television young children in Indonesia watch," said Dina L.G. Borzekowski, EdD, the study's lead author and associate professor in the Bloomberg School's Department of Health, Behavior and Society. She continued, "Mostly the shows children were seeing were of adult nature or dubbed episodes of Sponge Bob Squarepants and Scooby-Doo. In contrast, Jalan Sesama was created in Indonesia for Indonesian children. With this study, we present evidence that when a culturally and age-appropriate show is offered, it can change the lives of preschoolers. Our data show that 4, 5, and 6 year olds learned important and healthy messages."

Using a randomized experimental research study design, Borzekowski and co-author Holly K. Henry, a current doctoral student at the Bloomberg School of Public Health, examined the effect of a 14-week intervention on 160 children in Pandeglang District of Indonesia's Banten Province. The children, ranging in age from 3 to 6 years, were questioned on their knowledge and skills at the beginning and conclusion of the 14-week intervention. In addition to showing improvement in literacy, mathematics and early cognitive skills, the study found that children with the greatest exposure to Jalan Sesama performed best of any of the study groups, even after adjusting for baseline scores, age, gender, parents' education, and exposure to other media.

Jalan Sesama is produced by the Sesame Workshop with funding from the United States Agency for International Development. The program uses live action, puppetry (traditional and new), and animation to deliver relevant lessons on literacy, mathematics, safety, culture, environment and other subjects. Among the special Muppets^TM made for this specific show are Jabrik, a problem-solving and creative white rhino and Tantan, an environmentally-conscious orangutan.

A similar study was done by Borzekowski of Kilimani Sesame, a Tanzanian version of Sesame Street. In that study, published in July 2010, Borzekowski found that children with greater exposure showed more gains in cognitive, social and health outcomes than those with less exposure. Specifically, children who were more receptive to the Kilimani Sesame content had higher scores on tests of literacy and primary math skills, greater ability to describe appropriate social behaviors and emotions, and knew more about malaria and HIV/AIDS.

Funding for Jalan Sesama and research were provided by the United States Agency for International Development (USAID).

Seeing the effect smoking will have on their faces shocks women into giving up the habit, research from Staffordshire University has revealed.

A paper on the research has been published Dec. 6, in the British Journal of Health Psychology, published by BPS Journals in partnership with Wiley-Blackwell.

Using state-of-the-art morphing technology, researchers have been able to produce images of how smokers will age if they continue to smoke and if they stop.

The technique has been so successful that over two thirds of participants in the project said they will quit smoking as a direct consequence of seeing how their appearance will change.

The research has been funded by Stoke-on-Trent NHS Primary Care Trust (PCT).. It has involved 47 women aged between 18 and 34 years of age.

Professor Sarah Grogan, Project Lead and Professor of Health Psychology, said: "Using state-of-the-art age progression software we have been able to take a picture of women's faces and show them how they will age if they smoked and if they stopped.

"We found that women were very concerned about the impact of ageing on their faces in general and in particular the additional impact of smoking on their skin.

"Many experienced a physical shock reaction, including reports of nausea, to seeing how they would age if they continued to smoke.

"And they reported being highly motivated to quit smoking as a result of the intervention and many said that they would take active steps to quit having seen how they would look if they continued to smoke."

As well as Professor Grogan, the other members of the research team at Staffordshire University are Keira Flett, Research Assistant, and Professor David Clark-Carter.

They plan to retest the research participants, six months after they took part in the intervention, to determine whether they continued to smoke. But from the success of initial feedback, it is hoped the technology can be used more widely.

Professor Grogan said: "This is the first research investigating age-progression morphing software in this country, and we're hoping that eventually the findings can be implemented in stop smoking services across the UK."

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Journal Reference:

1. Sarah Grogan, Keira Flett, David Clark-Carter, Brendan Gough, Rachel Davey, Deborah Richardson and Giri Rajaratnam. Women Smokers' Experiences of an Age-appearance Anti-smoking Intervention: A Qualitative Study. British Journal of Health Psychology, 2010; DOI: 10.1348/2044-8287.002006

— Researchers have long argued that marriage generally reduces illegal and aggressive behaviors in men. It remained unclear, however, if that association was a function of matrimony itself or whether less "antisocial" men were simply more likely to get married.

The answer, according to a new study led by a Michigan State University behavior geneticist, appears to be both.

In the December issue of the Archives of General Psychiatry, online December 6, S. Alexandra Burt and colleagues found that less antisocial men were more likely to get married. Once they were wed, however, the marriage itself appeared to further inhibit antisocial behavior.

"Our results indicate that the reduced rate of antisocial behavior in married men is more complicated than we previously thought," said Burt, associate professor of psychology. "Marriage is generally good for men, at least in terms of reducing antisocial behavior, but the data also indicate that it's not random who enters into the state of marriage."

The study is the first to investigate the effects of marriage on antisocial behavior using a genetically informative twin sample to rule out the effects of genes on these associations. The researchers examined the data of 289 pairs of male twins. The twins were assessed four times, at ages 17, 20, 24 and 29.

The study found that men with lower levels of antisocial behavior at ages 17 and 20 were more likely to have married by age 29 (researchers refer to the act of entering into marriage as a selection process). This is noteworthy since previous studies found little support that selection process influenced reduced rates of antisocial behavior among married men.

Burt said her finding may differ from past studies because marital rates have declined significantly in recent years, whereas marriage was more of the norm in the 1950s, meaning selection likely wasn't much of a factor.

Once the men were married, rates of antisocial behavior declined even more. When comparing identical twins in which one twin had married while the other had not, Burt said, the married twin generally engaged in lower levels of antisocial behavior than did the unmarried twin.

Burt said it's unlikely that marriage inhibits men's antisocial behavior directly, but rather that marriage is a marker for other factors such as social bonding or less time spent with delinquent peers. Another factor that seems to be important is marriage quality; the effect of marriage on antisocial behavior tends to be stronger in better marriages.

Burt's co-researchers are M. Brent Donnellan and Mikhila Humbad from MSU; Brian Hicks from the University of Michigan; and Matt McGue and William Iacono from the University of Minnesota.

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Journal Reference:

1. An Examination of Selection vs Causation via a Longitudinal Twin Design S. Alexandra Burt, PhD; M. Brent Donnellan, PhD; Mikhila N. Humbad, MA; Brian M. Hicks, PhD; Matt McGue, PhD; William G. Iacono, PhD. Does Marriage Inhibit Antisocial Behavior?Arch Gen Psychiatry, 2010;67(12):1309-1315 DOI: 10.1001/archgenpsychiatry.2010.159