Quitting Smoking Enhances Personality Change

"The data indicate that for some young adults smoking is impulsive," said Andrew Littlefield, a doctoral student in the Department of Psychology in the College of Arts and Science. "That means that 18-year-olds are acting without a lot of forethought and favor immediate rewards over long term negative consequences. They might say, 'I know smoking is bad for me, but I'm going to do it anyway.' However, we find individuals who show the most decreases in impulsivity also are more likely quit smoking. If we can target anti-smoking efforts at that impulsivity, it may help the young people stop smoking."

In the study, MU researchers compared people, aged 18-35, who smoked with those who had quit smoking. They found that individuals who smoked were higher in two distinct personality traits during young adulthood:

• impulsivity -- acting without thinking about the consequences
• neuroticism -- being emotionally negative and anxious, most of the time

Littlefield found that those with higher levels of impulsivity and neuroticism were more likely to engage in detrimental behaviors, such as smoking. However, Littlefield also found that those who quit smoking had the biggest declines in impulsivity and neuroticism from ages 18 to 25.

"Smokers at age 18 had higher impulsivity rates than non-smokers at age 18, and those who quit tended to display the steepest declines in impulsivity between ages 18 and 25," Littlefield said. "However, as a person ages and continues to smoke, smoking becomes part of a regular behavior pattern and less impulsive. The motives for smoking later in life -- habit, craving, loss of control and tolerance -- are key elements of smoking dependence and appear to be more independent of personality traits."

Despite the evidence from this study, substance use is still a complex relationship of genetic and environmental factors, Littlefield said.

The study, "Smoking Desistance and Personality Change in Emerging and Young Adulthood," has been accepted by the journal Nicotine and Tobacco Research. The study was co-authored by Kenneth J. Sher, a professor in the MU Department of Psychology.

Littlefield says the tobacco use study will contribute to ongoing research on the relationship between personality and substance abuse. He recently received a $30,000 grant from the National Institutes of Health to study genetic influences on personality and alcohol drinking motives.

A Father's Stress May Affect His Unborn Children

The risk of developing depression, which is significantly increased by exposure to chronic stress, is influenced by both environment and genetics. The interplay of these two factors is quite complex, but in fact, there is even a third factor that most of us know nothing about -- epigenetics. Epigenetics is the science of changes in genetic expression that are not caused by actual changes in DNA sequencing. It is these mechanisms that have been the recent focus of intergenerational investigations into the transmission of stress vulnerability.

Inheritance is complex. We've all known that mothers and fathers have tremendous influence on their children, but "this study highlights how complicated the relationship between genetic, epigenetic, and environmental contributions can be with regards to the inheritance of important behavioral traits," commented Dr. John Krystal, editor of Biological Psychiatry.

Most work to date has focused on maternal effects. In this fascinating new study, researchers investigated paternal effects instead, and found that male mice exposed to chronic stress pass those stress behaviors along to their offspring. Both their male and female offspring showed increased depression and anxiety-like behaviors, although the effects were stronger in males. Importantly, these behavioral changes were only present in offspring produced through natural reproduction, and not in those offspring that were produced via in vitro fertilization. That interesting twist suggests that most stress-related vulnerabilities are transmitted to subsequent generations behaviorally, rather than epigenetically.

"This type of translational animal work is important to help scientists focus their work in humans," explained lead author Dr. Eric Nestler, from Mount Sinai School of Medicine in New York. "These findings in mice raise the possibility that part of an individual's risk for clinical depression or other stress-related disorders may be determined by his or her father's life exposure to stress, a provocative suggestion that now requires direct study in humans."

New Technique to Help Catch Sexual Offenders: Scientists Detect Condom Lubricant On Fingermarks for the First Time

There has been an increase in the use of condoms by sexual offenders, likely due to both to the risk of sexually transmitted diseases and to prevent the transfer of DNA evidence. The method developed by researchers at the University's Biomedical Research Centre (BMRC) can detect condom lubricant on fingermarks left by a suspect at a crime scene.

This can link a suspect, identified by their fingermark, to the crime in one analysis and can aid police in proving that an offence has taken place. And it is hoped the technique might be used to match lubricant found on a fingermark with residues from vaginal swabs collected from the victim.

Sexual Offenders Hoping To outsmart police by using a condom during their crimes may be out of luck thanks to a technique, being developed at Sheffield Hallam University, that can prove they have had contact with a condom & place them at the scene of the crime.

Researchers successfully detected lubricant from two widely available condom brands on fingermarks for the first time, and the technique was proven to be successful even on fingermarks left several weeks before analysis.

And the academics hope the technique can eventually be used to identify distinctive lubricants that could indicate a specific condom manufacturer and possibly even a particular brand. This would allow the forensic case to be profiled in an even stronger way.

For the study, researchers used MALDI-MSI (matrix-assisted laser desorption/ionisation mass spectrometry imaging), a powerful technology that can be used to map fingermark ridge patterns.

Dr Simona Francese, from the University's BMRC, said: "Offenders are increasingly aware of forensic issues and it is common now for condoms to be used and removed from the scene of a sexual assault. However, they are less likely to consider the possibility of lubricant transferring onto their fingertips and then into fingermarks left at the scene.

"If condom lubricant can be detected in fingermarks it would improve the evidence for the prosecution by establishing the assailant's presence at the scene and, crucially, having had contact with a condom. This would enable forensic scientists to provide further support to the evidence in alleged cases of sexual assault."