Ian Stevenson: Birthmarks and birth defects corresponding to wounds on deceased persons

Discussion

Because most (but not all) of these cases develop among persons who believe in reincarnation, we should expect that the informants for the cases would interpret them as examples according with their belief; and they usually do. It is necessary, however, for scientists to think of alternative explanations.

The most obvious explanation of these cases attributes the birthmark or birth defect on the child to chance, and the reports of the child’s statements and unusual behavior then become a parental fiction intended to account for the birthmark (or birth defect) in terms of the culturally accepted belief in reincarnation. There are, however, important objections to this explanation.

First, the parents (and other adults concerned in a case) have no need to invent and narrate details of a previous life in order to explain their child’s lesion. Believing in reincarnation, as most of them do, they are nearly always content to attribute the lesion to some event of a previous life without searching for a particular life with matching details.

Second, the lives of the deceased persons figuring in the cases were of uneven quality both as to social status and commendable conduct. A few of them provided models of heroism or some other enviable quality; but many of them lived in poverty or were otherwise unexemplary. Few parents would impose an identification with such persons on their children.

Third, although in most cases the two families concerned were acquainted (or even related), I am confident that in at least 13 cases (among 210 carefully examined with regard to this matter) the two families concerned had never even heard about each other before the case developed. The subject’s family in these cases can have had no information with which to build up an imaginary previous life which, it later turned out, closely matched a real one. In another 12 cases the child’s parents had heard about the death of the person concerned, but had no knowledge of the wounds on that person. Limitations of space for this article oblige me to ask readers to accept my appraisal of these 25 cases for this matter; but in my forthcoming work I give a list of the cases from which readers can find the detailed reports of the cases and from reading them judge this important question for themselves.

Fourth, I think I have shown that chance is an improbable interpretation for the correspondences in location between two or more birthmarks on the subject of a case and wounds on a deceased person.

Persons who reject the explanation of chance combined with a secondarily confected history may consider other interpretations that include paranormal processes, but fall short of proposing a life after death. One of these supposes that the birthmark or birth defect occurs by chance and the subject then by telepathy learns about a deceased person who had a similar lesion and develops an identification with that person. The children subjects of these cases, however, never show paranormal powers of the magnitude required to explain the apparent memories in contexts outside of their seeming memories.

Another explanation, which would leave less to chance in the production of the child’s lesion, attributes it to a maternal impression on the part of the child’s mother. According to this idea, a pregnant woman, having a knowledge of the deceased person’s wounds, might influence a gestating embryo and fetus so that its form corresponded to the wounds on the deceased person. The idea of maternal impressions, popular in preceding centuries and up to the first decades of this one, has fallen into disrepute. Until my own recent article (Stevenson, 1992) there had been no review of series of cases since 1890 (Dabney, 1890); and cases are rarely published now (Williams and Pembroke, 1988).

Nevertheless, some of the published cases — old and new — show a remarkable correspondence between an unusual stimulus in the mind of a pregnant woman and an unusual birthmark or birth defect in her later-born child. Also, in an analysis of 113 published cases I found that the stimulus occurred to the mother in the first trimester in 80 cases (Stevenson, 1992). The first trimester is well known to be the one of greatest sensitivity of the embryo/fetus to recognized teratogens, such as thalidomide (Nowack, 1965) and rubella (Hill, Doll, Galloway, and Hughes, 1958). Applied to the present cases, however, the theory of maternal impression has obstacles as great as the normal explanation appears to have.

First, in the 25 cases mentioned above, the subject’s mother, although she may have heard of the death of the concerned deceased person, had no knowledge of that person’s wounds.

Second, this interpretation supposes that the mother not only modified the body of her unborn child with her thoughts, but after the child’s birth influenced it to make statements and show behavior that it otherwise would not have done. No motive for such conduct can be discerned in most of the mothers (or fathers) of these subjects.

It is not my purpose to impose any interpretation of these cases on the readers of this article. Nor would I expect any reader to reach even a preliminary conclusion from the short summaries of cases that the brevity of this report entails. Instead, I hope that I have stimulated readers to examine the detailed reports of many cases that I am now in the process of publishing (Stevenson, forthcoming). “Originality and truth are found only in the details” (Stendhal, 1926).

Acknowledgements

I am grateful to Drs. Antonia Mills and Emily W. Cook for critical comments on drafts of this paper. Thanks are also due to the Bernstein Brothers Parapsychology and Health Foundation for the support of my research.

Correspondence and requests for reprints should be addressed to: Ian Stevenson, M.D., Division of Personality Studies, Box 152, Health Sciences Center, University of Virginia, Charlottesville, VA 22908

References

Cockayne, E, A. (1933). Inherited abnormalities of the skin. London: Oxford University Press.

Cook, E. W., Pasricha, S, Samararatne, G, Win Maung, & Stevenson, I. (1983). Review and analysis of “unsolved” cases of the reincarnation type: II. Comparison of features of solved and unsolved cases, Journal of the American Society for Psychical Research, 77, 1 15-135.

Dabney, W. C. (1890). Maternal impressions. In J. M. Keating (Ed.), Cyclopaedia of the diseases of children, Vol. 1 , (pp. 1 9 1 -2 1 6). Philadelphia: J. B. Lippincott.

Denaro, S. J. ( 1944). The inheritance of nevi. Journal of Heredity, 35, 2 1 5- 1 8.

Fatteh, A. (1976). Medicolegal investigation of gunshot wounds. Philadelphia: J. B. Lippincott.

Frantz, C. H., & O’Rahilly, R.(1961). Congenital skeletal limb deficiencies. Journal of Bone and Joins Surgery: 43-A, 1202-24.

Gordon, I., & Shapiro, H. A. (1982). Forensic medicine: A guide to principles. (2nd ed.) London: Churchill Livingstone.

Hill, A, B,, Doll, R,, Galloway, T. M., & Hughes, J.P.W. (1958). Virus diseases in pregnancy and congenital defects. British Journal of Preventive and Social Medicine, 12, 1-7.

Maruri, C. A. (1961). La herencia en dermarologia. (2nd ed.) Santander: Aldus, S.A. Artes Graficas.

Mills, A. (1989). A replication study: Three cases of children in northern India who are said to remember a previous life. Journal of Scientific Exploration, 3, 133-184.

Nelson, K., & Holmes, L. B. (1989). Malformations due to presumed spontaneous mutations in newborn infants. New England Journal of Medicine, 320, 19-23.

Nowack, E, (1965). Die sensible Phase bei der Thalidomid- Embryopathie. Humangenetik, I, 516-36.

Pack, G. T., & Davis, J. (1956). Moles. New York State Journal of Medicine, 56, 3498-3506.

Pack, G. T., Lenson, N. & Gerber, D. M. (1952). Regional distribution of moles and melanomas. AMA Archives of Surgery. 65, 862-70.

Smith, D. W. (1982). Recognizable patterns of human malformation. (3rd ed.) Philadelphia: W. B·Saunders.

Spalteholz. W· (1943). Hand atlas of human anatomy. Translated by L. E Barker. 7th English ed. Philadelphia: J,B. Lippincott.

Stendhal (1926). Lucien Leuwen. Paris: Librairie Ancienne Honor 6 Champion, 4, 169.

Stevenson, I. (1975). Cases of the reincarnation type. I. Ten cases in India. CharlottesviIle: University Press of Virginia.

Stevenson, I. (1983). American children who claim to remember previous lives. Journal of Nervous and Mental Disease, 17 1, 742-748.

Stevenson, I. (1987). Children who remember previous lives. Charlottesville: University Press of Virginia.

Stevenson, I. ( 1990). Phobias in children who claim to remember previous lives. Journal of Scientific Exploration, 4, 243-254.

Stevenson, I. (1992). A new look at maternal impressions: An analysis of 50 published cases and reports of two recent examples. Journal of Scientific Exploration, 6, 353-373.

Stevenson, I. (Forthcoming). Birthmarks and birth defects: A contribution to their etiology.

Williams, H. C., & Pembroke, A. C. (1988). Naevus of Jamaica. Lancet, 11, 915.

Wilson, J. G. (1973). Environment and birth defects. New York: Academic Press.

What’s in a name? The surprising ways your name affects your life

From dating to job prospects, a name has remarkable power over the path of its owner’s life.

I was at a party for Bastille Day in Paris a few years back, and we were leaning over the balcony to watch the fireworks. A cute French girl sat next to me, but after a few flirty glances the moment was entirely ruined with the most basic of interactions: “What’s your name?” she asked in French. “Cody,” I said.

That was it. We were done. “Co-zee?” she said, sounding out the entirely foreign name, looking more disgruntled with each try. “Col-bee?” “Cot-ee?”

I tried a quick correction, but I probably should’ve just lied, said my name was Thomas or Pierre like I did whenever I ordered take-away or made restaurant reservations. Not being able to pronounce a name spells a death sentence for relationships. That’s because the ability to pronounce someone’s name is directly related to how close you feel to that person. Our brains tend to believe that if something is difficult to understand, it must also be high-risk.

In fact, companies with names that are simple and easy to pronounce see significantly higher investments than more complexly named stocks, especially just after their initial public offerings when information on the stock’s fundamentals are most scarce. People with easier to pronounce names are also judged more positively and tend to be hired and promoted more often than their more obscurely named peers.

There are more variables at play than just pronunciation, though. In competitive fields that have classically been dominated by men, such as law and engineering, women with sexually ambiguous names tend to be more successful. This effect is known as the Portia Hypothesis (named for the heroine of Shakespeare’s The Merchant of Venice who disguises herself as a lawyer’s apprentice and takes on the name Balthazar to save the titular merchant, Antonio). A study found that female lawyers with more masculine names – such as Barney, Dale, Leslie, Jan, and Rudell – tend to have better chances of winning judgeships than their more effeminately named female peers. All else being equal, changing a candidate’s name from Sue to Cameron tripled a candidate’s likelihood of becoming a judge; a change from Sue to Bruce quintupled it.

Names work hard: They can affect who gets into elite schools, what jobs we apply for, and who gets hired. Our names can even influence what cities we live in, who we befriend, and what products we buy since, we’re attracted to things and places that share similarities to our names.

A name is, after all, perhaps the most important identifier of a person. Most decisions are made in about three to four seconds of meeting someone, and this “thin-slicing” is surprisingly accurate. Something as packed full of clues as a name tends to lead to all sorts of assumptions and expectations about a person, often before any face-to-face interaction has taken place. A first name can imply race, age, socioeconomic status, and sometimes religion, so it’s an easy – or lazy – way to judge someone’s background, character, and intelligence.

These judgments can start as early as primary school. Teachers tend to hold lower expectations for students with typically black-sounding names while they set high expectations for students with typically white – and Asian – sounding names. And this early assessment of students’ abilities could influence students’ expectations for themselves.

On this year’s French baccalaureate, an exam that determines university placement for high school students, test-takers named Thomas (for boys) and Marie (for girls) tended to score highest. These are, you will note, typically white, French, middle- or upper-class names. One could imagine these students were given the advantage of high expectations and self-perception, whether or not they had the money and support that comes with the socioeconomic background associated with those names.

People change their names for different reasons. Angelina Voight became Jolie to estrange herself from her father and Natalie Hershlag became Portman to maintain her family’s privacy. The inclusion of a middle initial in formal correspondence is a strong identifier of intelligence (even though the New York Times claims it’s a dying trend). But what if parents from disadvantaged circumstances gave their children “advantaged” names? Could just a name really have that great of an effect on a person’s career and future?

A 2004 study showed that all else being equal, employers selected candidates with names like Emily Walsh and Greg Baker for callbacks almost 50 percent more often than candidates with names like Lakisha Washington and Jamal Jones. Work experience was controlled and the candidates never met face-to-face with the employer so all that was being tested was the effect of the candidate’s name. The researchers concluded that there was a great advantage to having a white-sounding name, so much so that having a white-sounding name is worth about eight years of work experience. “Jamal” would have to work in an industry for eight years longer than “Greg” for them to have equal chances of being hired, even if Jamal came from a privileged background and Greg from an underprivileged one. (Perhaps that’s why mega-celebrities can get away with giving their children peculiar names. A résumé with the name North West probably wouldn’t do as well as James Williamson – unless Papa Kanye called up the boss.)

After the girl at the party had so much trouble saying my name, I asked what her name was. “Edwige,” she said. It’s a lovely name, very French, but it is also pronounced the exact same way as “Hedwige,” which just so happens to be the French version of Hedwig, the owl in Harry Potter. “Don’t make fun,” she said, and I didn’t. But neither did we talk very much for the rest of the night. But still, I wonder what would’ve happened if I had been a Pierre and she a Marion. Perhaps we would’ve gotten along quite well that night, perhaps we would’ve quickly trusted each other. Perhaps I’d have a date this weekend.

Cody C. Delistraty is a writer and historian based in Paris. He has worked for the Council on Foreign Relations, UNESCO, and NBC News.

Not in front of the kids: Children can detect their parents’ emotional suppression

“Not in front of the kids.” It’s an age-old plea for parents to avoid showing conflict and strong negative emotions around their children. But new research from a Washington State University scientist disagrees, showing that it’s better to express negative emotions in a healthy way than to tamp them down.

After people suppress compassionate feelings, they lose a bit of their commitment to morality.

Sara Waters, an assistant professor in the Department of Human Development on the WSU Vancouver campus, and co-authors from the University of California, Berkley and the University of California, San Francisco, write about their findings in the journal Emotion.

“We wanted to look at how we suppress emotions and how that changes the way parents and kids interact,” Waters said. “Kids pick up on suppression, but it’s something a lot of parents think is a good thing to do.”

The study was conducted on 109 mothers or fathers with their children in San Francisco. The sample was split almost evenly between mothers and fathers, as the scientists wanted to see if any differences existed in the results between genders.

First, the researchers gave the parent a stressful task: public speaking with negative feedback provided by the audience. Then, the parents were given an activity to complete with their children, with some randomly told to suppress their emotions. The others were told to act naturally.

The activity was the same for all pairs, working together to assemble a Lego project. However, the kids, ages 7-11, received the paper instructions, but weren’t allowed to touch the Legos. The parents had to assemble the project, but couldn’t look at the instructions. This forced them to work together closely to succeed.

“We were interested in behaviors,” Waters said. “We looked at the responsiveness, warmth, quality of the interactions, how the parent provided guidance for the child.”

Waters and her co-authors had a team of undergraduate research assistants from WSU Vancouver watch all 109 videos of the interactions to mark every instance of warmth, guidance, and other emotions.

Both the parent and the child were also hooked up to a variety of sensors, to measure heart rate, stress levels, etc. The study authors combined that data with the coding done by the assistants to get their results.

“The act of trying to suppress their stress made parents less positive partners during the Lego task,” Waters said. “They offered less guidance, but it wasn’t just the parents who responded. Those kids were less responsive and positive to their parents. It’s almost like the parents were transmitting those emotions.”

Gender Differences

Since the team made such an effort to get an equal mother/father split, they were able to make further discoveries. It turns out that emotional suppression made kids more sensitive to their mothers. The children showed less change in their responses when a father was suppressing his emotions, Waters said.

For now, there isn’t enough data on fathers and their children in emotion studies to say why that is.

“We just don’t have much research on dads because it’s really hard to get dads to participate in research projects,” Waters said. “It took a LOT of work to get enough dads in this study.”

In previous research, it has been found that, in general, men are more likely to suppress their emotions. Waters suspects that it’s possible a father suppressing his emotions isn’t unusual, so it didn’t have as much impact on the kids in this study.

Kids Pick Up Emotional Residue

Waters said there are dozens of studies that show kids are good at picking up “emotional residue” from their parents.

“Kids are good at picking up subtle cues from emotions,” she said. “If they feel something negative has happened, and the parents are acting normal and not addressing it, that’s confusing for them. Those are two conflicting messages being sent.”

Rather than suppressing emotions in front of your children, Waters suggests the best course of action is to let kids see a healthy conflict, from start to resolution.

Journal of Social and Clinical Psychology: Facebook can cause depression

A new report conducted by psychologists at the University of Pennsylvania have determined that an excessive amount of time on “social media” sites like Facebook, Instagram, and Snapchat are making millennials depressed.”It was striking,” said Melissa Hunt, a psychology professor at the University of Pennsylvania, who led the study. “What we found over the course of three weeks was that rates of depression and loneliness went down significantly for people who limited their (social media) use.”

The study, “No More FOMO: Limiting Social Media Decreases Loneliness and Depression,” is being published in December’s Journal of Social and Clinical Psychology.

Researchers recruited 143 students for two different trials, one in the spring semester and one in the fall semester. Each subject was required to have a Facebook, Instagram, and Snapchat account, plus an Apple iPhone. They collected data on the students for about a week to get a baseline reading of their social media usage, and also had them submit questionnaires that assessed their mental health according to seven different factors: social support, fear of missing out, loneliness, autonomy, and self-acceptance, anxiety, depression, and self-esteem.

“Here’s the bottom line,” Hunt explained to Science Daily. “Using less social media than you normally would leads to significant decreases in both depression and loneliness. These effects are particularly pronounced for folks who were more depressed when they came into the study.”

The link between increasing social media usage and mental health issues have already been established in past studies. But, depression and loneliness have not, until now.

Hunt said lonely and depressed people use platforms like Facebook because they are seeking social connections. Social media as a whole is making millennials more lonely, and increasingly depressed.

The study did not cover why social media makes people depressed. Hunt does provide an example:

The first is “downward social comparison.” A person reviews their feed and finds countless posts of their friends enjoying wonderful experiences. The result: “You’re more likely to think your life sucks in comparison,” said Hunt.

Social media sites are a vital tool for many millennials in the modern economy. This means they cannot cut it out altogether, Hunt Said.

That is why the study focused on cutting back usage. While ten minutes might not seem like much, the study showed it certainly helped with depression.

Bad Science – Psychopaths and successful creative types have one thing in common

They say you should never meet your heroes. There’s plenty of reasons why, but in the case of your creative heroes, it might be because they’re jerks.

The idea of the “cantankerous creative” has likely been around since the first arrogant caveman learned to make fire. Pablo Picasso carried around a revolver loaded with blanks that he’d fire at people he disliked. H.P. Lovecraft was a staggering racist, even for his time. Thomas Edison happily electrocuted an elephant to discredit his rival, Nikola Tesla. It seems like creative people – whether gifted in the visual arts, science, writing, or what have you – are often thoroughly unpleasant people.

While creative success may make one bigheaded, an emerging stream of research is showing that creativity and being a real jerk may actually have a more intimate relationship. In fact, for some people, being a bit of a psychopath might nudge one toward creative success.

The artistic psychopath

One study in particular has shed light on the link between creativity and psychopathy. Published in Personality and Individual Differences, in the spring of 2017, A.J.R. Galang’s study looked at creative success and how it matched up with the so-called Dark Triad of personality traits: narcissism, Machiavellianism, and psychopathy.

Participants were instructed to indicate how much they agreed with a given statement presented over a series of surveys designed to measure both creative achievements (with statements like “My work has been critiqued in a national publication”) and Dark Triad personalities (with statements like “Payback needs to be quick and nasty”). Galang found that creative achievement in a variety of arts, ranging from creative writing to the culinary arts, was consistently associated with higher narcissism and psychopathy.

Prior evidence showed that narcissists tended to inflate their successes on such questionnaires, but, as Galang writes,

The finding for psychopathy is much more interesting […] People with tendencies towards psychopathy would have less reason than narcissists to falsely portray themselves as creative. Therefore, it is reasonable to suspect that this association might imply a substantial link between trait psychopathy and creativity.



Where psychopathy and creativity overlap

Based on these findings, Galang dug more deeply into the link between psychopathy and creativity. One model of psychopathy breaks the trait down into three broad categories: boldness, meanness, and disinhibition. Psychopaths don’t experience fear and stress very much (boldness), are often aggressive and lacking in empathy (meanness), and behave impulsively (disinhibition). Galang surveyed a new sample, again measuring participants’ creative achievements in various fields of art in addition to measuring their boldness, meanness, and disinhibition.

The findings were clear. Most artists tended to score high in psychopathic boldness, which Galang characterized as a “kind of emotional disinhibition that should be associated with less restricted decision-making […] and creative ideation.” This is in contrast to psychopathic disinhibition, which is “mostly associated with problems with control and aggression, and also with negative affect.”

Although these findings held up across the board of artistic disciplines, there were a few interesting outliers. Successful architects scored high in boldness, meanness, and disinhibition. In the first survey, they also scored highly in Machiavellianism, narcissism, and psychopathy. So, maybe don’t invite any architects to your next dinner party. Creative writing was negatively associated with meanness and disinhibition but scored highly in boldness, and comedians were both strikingly bold and mean.

Testing the theory

But so far, this research relied on self-reports of creativity or psychopathic tendencies. Based on the idea that creative people are emotionally disinhibited in much the same way as psychopaths, Galang recruited some participants to perform the Iowa Gambling Task – a common cognitive test designed to measure risk-taking and decision-making – while measuring skin conductance responses, which spike in response psychological stress and anxiety.

After completing the task, participants were asked to perform two divergent-thinking tasks designed to approximate general creativity. The first was to come up with as many uses for a bottle as possible, and the second was to consider the consequences of a scenario where people no longer needed to sleep.

The responses were then graded for their creativity by different researchers. For instance, some highly creative responses to no longer needing to sleep where that moon bathing would become a fad or that Santa Claus would be caught in the act on Christmas. Those individuals who felt little or no stress in the gambling task tended to perform better creatively.

What does this mean?

Together, this research provides evidence for what Galang calls the “prosocial psychopath model of creativity.” Many (but not all) highly creative people tend to have personality traits similar to those of psychopaths. Their emotional disinhibition expresses itself in striking works of art as well as rude remarks (or in Picasso’s case, firing pistols at people). At the same time prosocial psychopaths aren’t quite so mean or impulsive as a true psychopath; hence, they are “prosocial.” Success in art may, in some cases, be due to boldness bordering on psychopathy.

Cortisol the ‘stress hormone’ linked to early toll on thinking ability

Brain changes, visible on scans, are also associated with Alzheimer’s precursors

The stresses of everyday life may start taking a toll on the brain in relatively early middle age, new research shows. The study of more than 2,000 people, most of them in their 40s, found those with the highest levels of the stress-related hormone cortisol performed worse on tests of memory, organization, visual perception and attention.

Higher cortisol levels, measured in subjects’ blood, were also found to be associated with physical changes in the brain that are often seen as precursors to Alzheimer’s disease and other forms of dementia, according to the study published in October in Neurology.

The link between high cortisol levels and low performance was particularly strong for women, the study found. But it remains unclear whether women in midlife are under more stress than men or simply more likely to have their stress manifested in higher cortisol levels, says lead researcher Sudha Seshadri. A professor of neurology, she splits her time between Boston University and The University of Texas Health Science Center at San Antonio, where she is the founding director of the Glenn Biggs Institute for Alzheimer’s & Neurodegenerative Diseases.

Working on the study “made me more stressed about not being less stressed,” Seshadri says, laughing. But, she adds, the bottom line is serious: “An important message to myself and others is that when challenges come our way, getting frustrated is very counterproductive-not just to achieving our aims but perhaps to our capacity to be productive.”

The study is the largest of its kind to look at these factors and tightens the link between cortisol, midlife stress and brain changes, says Pierre Fayad, medical director of the Nebraska Stroke Center at the University of Nebraska Medical Center, who was not involved in the new research. “It confirms some of the previous suspicions,” he says. “Because of its quality, it gives a lot more credibility.”

Bruce McEwen, a neuroscientist and cortisol expert at The Rockefeller University who also was not part of the study, says he found it “frankly remarkable.” Cortisol, he notes, is necessary for life-so it is obviously not all bad. But stress can lead people to potentially problematic behaviors such as smoking, drinking and eating unhealthy food. “Cortisol is itself the tip of the iceberg of things that are going on in a person’s life and a person’s body,” he says.

The new research included volunteers from the Framingham Heart Study, a 70-year-old study of residents from a Boston suburb. Researchers are now studying the grandchildren of the original participants, most of whom were white, middle class and suburban, Seshadri says. Although the scientists did not ask participants what kinds of specific stresses they were under on the day their blood was drawn, she says the volunteers were able to come in for a three-to-four-hour examination-so “you would say they were at a reasonably stable point in their life.”

Yet even these relatively young and apparently well-off people showed signs of brain changes, both in brain scans and in their performance. “This is the range of stress that a group of average Americans would experience,” Seshadri says. The highest cortisol levels were associated with changes that could be seen on an MRI scan of the brain, the study found.

Cortisol does not distinguish between physical and mental stress, so some of the people with high levels might have had physical illnesses such as diabetes that drove up their cortisol levels, Seshadri says. It is also possible levels of the hormone might spike in people’s blood if they are already undergoing brain changes-that is, the elevated cortisol could be the result of the changes rather than their cause-she says. But she thinks this is unlikely because the trial participants were so young. Each subject’s cortisol level was measured only once (in the morning), so the measurements do not reflect changes over time or variations throughout the day, she notes.

The volunteers were given tasks such as copying a shape they were shown, or being asked to repeat a story they had been told 20 minutes earlier. The differences in performance were subtle, Seshadri says. She could not immediately tell whether subjects had higher or lower cortisol levels based on how well they carried out the tasks. “It was more that in terms of group averages there was a real difference,” she explains.

Earlier research has shown weaker-than-average performances on tests like these are associated with a higher risk of dementia decades later, and Seshadri says high stress levels in midlife might be one of many factors that contribute to dementia. Understanding that link might offer a potential opportunity to reduce risk-but she cautions research has not yet shown conclusively that lowering cortisol levels will reduce the risk of Alzheimer’s.

Other research has shown cortisol levels can be reduced with adequate sleep, exercise, socializing and relaxing mental activities such as meditation. “There are a number of intriguing, fairly simple things that have been shown to change these levels,” Seshadri says. “But whether they will in turn translate into better preservation of the brain is something that can only be determined in a clinical trial.”

Rockefeller University’s McEwen says other research suggests it is never too late to adopt a healthier lifestyle by taking steps like reducing stress, exercising regularly, eating a healthy diet, getting enough good-quality sleep and finding meaning in one’s life. “The life course is a one-way street,” he says. But “the brain does have the capacity for repairing.”