Narcissism has a higher health cost for men

The personality trait narcissism may have an especially negative effect on the health of men, according to a recent study published in PLoS ONE. "Narcissistic men may be paying a high price in terms of their physical health, in addition to the psychological cost to their relationships," says Sara Konrath, a University of Michigan psychologist who co-authored the study. Earlier studies by Konrath and others have shown that the level of narcissism is rising in American culture, and that narcissism tends to be more prevalent among males. The personality trait is characterized by an inflated sense of self-importance, overestimations of uniqueness, and a sense of grandiosity.

For the new study, Konrath and colleagues David Reinhard of the University of Virginia, and William Lopez and Heather Cameron of the University of Michigan examined the role of narcissism and sex on cortisol levels in a sample of 106 undergraduate students. Cortisol, which can be measured through saliva samples, is a widely used marker of physiological stress. The researchers measured cortisol levels at two points in time in order to assess baseline levels of the hormone, which signals the level of activation of the body's key stress response system, the hypothalamic-pituitary-adrenal (HPA) axis. Participants were not asked to complete any tasks that would elevate their stress. Elevated levels of cortisol in a relatively stress-free situation would indicate chronic HPA activation, which has significant health implications, increasing the risk of cardiovascular problems.

To assess participants' narcissism, the researchers administered a 40-item narcissism questionnaire that measures five different components of the personality trait. Two of these components are more maladaptive, or unhealthy – exploitativeness and entitlement; and the other three are more adaptive, or healthy – leadership/authority, superiority/arrogance, and self-absorption/self-admiration. "Even though narcissists have grandiose self-perceptions, they also have fragile views of themselves, and often resort to defensive strategies like aggression when their sense of superiority is threatened," says Reinhard. "These kinds of coping strategies are linked with increased cardiovascular reactivity to stress and higher blood pressure, so it makes sense that higher levels of maladaptive narcissism would contribute to highly reactive stress response systems and chronically elevated levels of stress."

Reinhard, Konrath and colleagues found that the most toxic aspects of narcissism were indeed associated with higher cortisol in male participants, but not in females. In fact, unhealthy narcissism was more than twice as large a predictor of cortisol in males as in females. They also found that there was no relationship between healthy narcissism and cortisol in either males or females. "These findings extend previous research by showing that narcissism may not only influence how people respond to stressful events, but may also affect how they respond to their regular day-to-day routines and interactions," says Konrath. "Our findings suggest that the HPA axis may be chronically activated in males high in unhealthy narcissism, even without an explicit stressor."

Why should narcissism affect males differently? "Given societal definitions of masculinity that overlap with narcissism – for example, the belief that men should be arrogant and dominant – men who endorse stereotypically male sex roles and who are also high in narcissism may feel especially stressed," Konrath suggests.

In future research, she hopes to examine why narcissism is not as physiologically taxing for women as it is for men, and also to examine the potential links between maladaptive narcissism and other physiological responses related to stress and poor coping, including inflammatory markers such as C-Reactive Protein.

With growing concern that excessive levels of fructose may pose a great health risk – causing high blood pressure, kidney disease and diabetes – researchers at the University of Colorado School of Medicine, along with their colleagues at the University of Florida, set out to see if two common sweeteners in western diets differ in their effects on the body in the first few hours after ingestion. The study, recently published in the journal Metabolism, took a closer look at high fructose corn syrup (HFCS) and table sugar (sucrose) and was led by Dr MyPhuong Le (now a postdoctoral fellow at the University of Colorado) and Dr Julie Johnson, a Professor of Pharmacogenomics at the University of Florida.

Both HFCS and sucrose have historically been considered to have nearly identical effects on the body. But this study finds that indeed there is a difference between the two. They found that the makeup of the sugars resulted in differences in how much fructose was absorbed into the circulation, and which could have potential impact on one's health. Sucrose is 50 percent fructose and 50 percent glucose that is bonded together as a disaccharide (complex carbohydrate) and HFCS is a mixture of free fructose (55%) and free glucose (45%). It's the difference in fructose amount that appears to create the ill health effects on the body.

Their study was conducted at the University of Florida, where they evaluated 40 men and women who were given 24 ounces of HFCS- or sugar-sweetened soft drinks. Careful measurements showed that the HFCS sweetened soft drinks resulted in significantly higher fructose levels than the sugar-sweetened drinks. Fructose is also known to increase uric acid levels that have been implicated in blood pressure, and the HFCS-sweetened drinks also resulted in a higher uric acid level and a 3 mm Hg greater rise in systolic blood pressure.

Dr Richard Johnson, a coauthor in the study and Chief of the Division of Renal Diseases and Hypertension at the University of Colorado, commented "Although both sweeteners are often considered the same in terms of their biological effects, this study demonstrates that there are subtle differences. Soft drinks containing HFCS result in slightly higher blood levels of fructose than sucrose-sweetened drinks, "said Johnson. "The next step is for new studies to address whether the long-term effects of these two sweeteners are different."

Max Planck researchers reveal the structure of the cellular protein degradation machinery

Mate competition by males over females is common in many animal species. During mating season male testosterone levels rise, resulting in an increase in aggressive behavior and masculine features. Male bonobos, however, invest much more into friendly relationships with females. Elevated testosterone and aggression levels would collide with this increased tendency towards forming pair-relationships.

Bonobos are among the closest living relatives of humans. Like other great apes they live in groups made up of several males and females. Contrary to other ape species however, male bonobos do not, in general, outrank female individuals and do not dominate them in mating contexts. This constellation suggests that the selection for typically masculine behavioral patterns like aggression, dominance and intrasexual competition are met with antagonistic forces: On one hand it is advantageous if a male outcompetes a fellow male. This, however, implies that there is increased aggression and an elevated level of testosterone in high-ranking males. On the other hand – as dominance relations between the sexes are rather balanced in bonobos – it is likely that males benefit from having friendly pair-relationships with female individuals. Studies with birds and rodents show that a tendency towards forming pair-relationships correlates with lower male aggression rates and testosterone levels.

In a current study, Martin Surbeck, Gottfried Hohmann, Tobias Deschner and colleagues of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, found that in wild bonobos high-ranking males were more aggressive and their mating success was higher when compared to lower-ranking males. Contrary to other species in which males compete fiercely over access to females, there was no correlation between dominance status or aggression with testosterone levels. In addition, the researchers found that high-ranking males invested more often than lower-ranking group members into friendly relationships with females. This suggests that these friendly relationships between the sexes are associated with lower male testosterone levels.

"Our study suggests that in bonobos – as in in humans – intersexual friendships result in hormonal patterns that we know from species in which male individuals are actively participating in raising their young and in which the two sexes enter lasting pair-relationships", says Martin Surbeck.

In cultures that permit men to take multiple wives, the intra-sexual competition that occurs causes greater levels of crime, violence, poverty and gender inequality than in societies that institutionalize and practice monogamous marriage. That is a key finding of a new University of British Columbia-led study that explores the global rise of monogamous marriage as a dominant cultural institution. The study suggests that institutionalized monogamous marriage is rapidly replacing polygamy because it has lower levels of inherent social problems. "Our goal was to understand why monogamous marriage has become standard in most developed nations in recent centuries, when most recorded cultures have practiced polygyny," says UBC Prof. Joseph Henrich, a cultural anthropologist, referring to the form of polygamy that permits multiple wives, which continues to be practiced in some parts of Africa, Asia, the Middle East and North America. "The emergence of monogamous marriage is also puzzling for some as the very people who most benefit from polygyny – wealthy, powerful men – were best positioned to reject it," says Henrich, lead author of the study that is published today in the journal Philosophical Transactions of the Royal Society. "Our findings suggest that that institutionalized monogamous marriage provides greater net benefits for society at large by reducing social problems that are inherent in polygynous societies."

Considered the most comprehensive study of polygamy and the institution of marriage, the study finds significantly higher levels rape, kidnapping, murder, assault, robbery and fraud in polygynous cultures. According to Henrich and his research team, which included Profs. Robert Boyd (UCLA) and Peter Richerson (UC Davis), these crimes are caused primarily by pools of unmarried men, which result when other men take multiple wives. "The scarcity of marriageable women in polygamous cultures increases competition among men for the remaining unmarried women," says Henrich, adding that polygamy was outlawed in 1963 in Nepal, 1955 in India (partially), 1953 in China and 1880 in Japan. The greater competition increases the likelihood men in polygamous communities will resort to criminal behavior to gain resources and women, he says.

According to Henrich, monogamy's main cultural evolutionary advantage over polygyny is the more egalitarian distribution of women, which reduces male competition and social problems. By shifting male efforts from seeking wives to paternal investment, institutionalized monogamy increases long-term planning, economic productivity, savings and child investment, the study finds. Monogamy's institutionalization has been assisted by its incorporation by religions, such as Christianity.

Monogamous marriage also results in significant improvements in child welfare, including lower rates of child neglect, abuse, accidental death, homicide and intra-household conflict, the study finds. These benefits result from greater levels of parental investment, smaller households and increased direct "blood relatedness" in monogamous family households, says Henrich, who served as an expert witness for British Columbia's Supreme Court case involving the polygamous community of Bountiful, B.C.

Monogamous marriage has largely preceded democracy and voting rights for women in the nations where it has been institutionalized, says Henrich, the Canadian Research Chair in Culture, Cognition and Evolution in UBC's Depts. of Psychology and Economics. By decreasing competition for younger and younger brides, monogamous marriage increases the age of first marriage for females, decreases the spousal age gap and elevates female influence in household decisions which decreases total fertility and increases gender equality.

Brain scans of people under the influence of the psilocybin, the active ingredient in magic mushrooms, have given scientists the most detailed picture to date of how psychedelic drugs work. The findings of two studies being published in scientific journals this week identify areas of the brain where activity is suppressed by psilocybin and suggest that it helps people to experience memories more vividly.

In the first study, published today in Proceedings of the National Academy of Sciences (PNAS), 30 healthy volunteers had psilocybin infused into their blood while inside magnetic resonance imaging (MRI) scanners, which measure changes in brain activity. The scans showed that activity decreased in "hub" regions of the brain – areas that are especially well-connected with other areas. The second study, due to be published online by the British Journal of Psychiatry on Thursday, found that psilocybin enhanced volunteers' recollections of personal memories, which the researchers suggest could make it useful as an adjunct to psychotherapy.

Professor David Nutt, from the Department of Medicine at Imperial College London, the senior author of both studies, said: "Psychedelics are thought of as 'mind-expanding' drugs so it has commonly been assumed that they work by increasing brain activity, but surprisingly, we found that psilocybin actually caused activity to decrease in areas that have the densest connections with other areas. These hubs constrain our experience of the world and keep it orderly. We now know that deactivating these regions leads to a state in which the world is experienced as strange." The intensity of the effects reported by the participants, including visions of geometric patterns, unusual bodily sensations and altered sense of space and time, correlated with a decrease in oxygenation and blood flow in certain parts of the brain.

The function of these areas, the medial prefrontal cortex (mPFC) and the posterior cingulate cortex (PCC), is the subject of debate among neuroscientists, but the PCC is proposed to have a role in consciousness and self-identity. The mPFC is known to be hyperactive in depression, so psilocybin's action on this area could be responsible for some antidepressant effects that have been reported. Similarly, psilocybin reduced blood flow in the hypothalamus, where blood flow is increased during cluster headaches, perhaps explaining why some sufferers have said symptoms improved under psilocybin.

In the British Journal of Psychiatry study 10 volunteers viewed written cues that prompted them to think about memories associated with strong positive emotions while inside the brain scanner. The participants rated their recollections as being more vivid after taking psilocybin compared with a placebo, and with psilocybin there was increased activity in areas of the brain that process vision and other sensory information.

Participants were also asked to rate changes in their emotional well-being two weeks after taking the psilocybin and placebo. Their ratings of memory vividness under the drug showed a significant positive correlation with their well-being two weeks afterwards. In a previous study of 12 people in 2011, researchers found that people with anxiety who were given a single psilocybin treatment had decreased depression scores six months later. Dr Robin Carhart-Harris, from the Department of Medicine at Imperial College London, the first author of both papers, said: "Psilocybin was used extensively in psychotherapy in the 1950s, but the biological rationale for its use has not been properly investigated until now. Our findings support the idea that psilocybin facilitates access to personal memories and emotions. "Previous studies have suggested that psilocybin can improve people's sense of emotional well-being and even reduce depression in people with anxiety. This is consistent with our finding that psilocybin decreases mPFC activity, as many effective depression treatments do. The effects need to be investigated further, and ours was only a small study, but we are interested in exploring psilocybin's potential as a therapeutic tool."

The researchers acknowledged that because the participants in this study had volunteered after having previous experience of psychedelics, they may have held prior assumptions about the drugs which could have contributed to the positive memory rating and the reports of improved well-being in the follow-up.

Functional MRI measures brain activity indirectly by mapping blood flow or the oxygen levels in the blood. When an area becomes more active, it uses more glucose, but generates energy in rapid chemical reactions that do not use oxygen. Consequently, blood flow increases but oxygen consumption does not, resulting in a higher concentration of oxygen in blood in the local veins.

In the PNAS study, the volunteers were split into two groups, each studied using a different type of fMRI: 15 were scanned using arterial spin labelling (ASL) perfusion fMRI, which measures blood flow, and 15 using blood-oxygen level-dependent (BOLD) fMRI. The two modalities produced similar results, strongly suggesting that the observed effects were genuine.