April 29, 2013 by Cara Flanagan.
A team of Californian researchers, led by Susan Charles, recently published a study linking daily hassles to depression (Charles et al., 2013). A group of just over 700 participants were studied for eight consecutive days. On each day they reported daily hassles and also how negative they were feeling. Ten years later the same participants were re-assessed. The researchers found that those participants who experienced negative emotions on days with high levels of daily hassles were more likely to be depressed. This suggests that people who are stressed by their daily hassles are more likely to suffer from mental health issues later in life.
October 8, 2012 by Cara Flanagan.
Here’s an interesting application of understanding stress. People who have spinal injuries usually lose control of their autonomic nervous system as well as their limbs, which means that their bodies do not respond to stress signals from the brain in the same way that normal people do – ‘normally’ an athlete, at the start of a race feels increased anxiety and the hypothalamus sends signals to the body to be prepared for fight/flight. Such arousal is important to perform well.
The bodies of people with spinal injuries don’t respond to such signals, so they have turned to a practice called ‘boosting’, where they intentionally break their toe or sit on their scrotum or something to generate pain signals that will kick start their body’s reaction to stress. The person will not feel any pain but blood pressure and heart rate will increase and performance improves. Not surprisingly the International Olympics committee has banned boosting for obvious health reasons. The problem is that some paralympic sports competitors don’t have injuries that disable their autonomic nervous systems so there are unfair disadvantages for those athletes. Nothing is simple.
October 4, 2011 by Cara Flanagan.
A recent study by Ramona Scotland (just published) is described on a recent edition of Healthcheck (listen here). The study did involve animals but points clearly to significant gender differences – females have stronger immune systems which means they become less ill and recover faster. There is a downside because women are also more susceptible to more autoimmune diseases because their immune systems are more sensitive.
Such differences are important because most research is conducted using men and the assumption is made that the findings apply to all people. For example if a drug is tested on men it may not function in the same way with women.
August 1, 2010 by Evie Bentley.
Women in our culture generally have richer social networks than men, and this observation has been used as part of the explanation for women coping better with stress and living longer. Now a meta-analysis has shown that a low number of friends, family, colleagues etc. in a person’s social network has similar negative effects on health and longevity as smoking, obesity, sedentary lifestyle or over-use of alcohol. The researchers say that their analysis was not able to differentiate between positive and negative social relationships, so having a good number of positive ones might give an even stronger effect on living healthier and longer!
Holt-Lunstad J, Smith TB, Layton JB. Social Relationships and Mortality Risk: A Meta-analytic Review. PLoS Medicine, 2010; 7 (7):
May 2, 2010 by Adrian Frost.
There really are some beautiful charts and diagrams here…. truly ‘descriptive statistics’. I can’t really do any of it justice by cramming it into a tiny blog post, but it’s well worth having a look at this venn diagram about drugs, for example. Or this interactive representation of the link between stress and work.
January 20, 2010 by Cara Flanagan.
A team at the University of London have just published a report of their study linking stress to atheroschlerosis (narrowing of the arteries), which is a major factor in heart attacks. Hamer et al. (2010) worked with 514 healthy men and women (mean age 62.9 years). The participants were given various tasks to increase their stress levels (such as the Stroop task). Cortisol levels in the saliva were measured before and after the stress tasks (cortisol is a hormone produced when we are stressed). Coronary artery calcification (thickening) was also assessed. The study found that only 40% of the participants had raised cortisol levels after the task but of this group there were significantly more people with thickened arteries. These results support the idea that hypothalamic pituitary adrenal activity (which produces cortisol) is a risk factor for CHD.
December 8, 2009 by Evie Bentley.
Diathesis-stress is an example of nature AND nurture, as it can be interpreted as a gene or genes switched on by environmental factors. Recently it’s been suggested that being lonely and stressed could affect the expression of cancer-linked genes, triggering their action. The research has been done in the USA on rats, comparing those kept in isolation with those living in groups. The former group had over three times the frequency of breast tumours than the latter group, and their breast tumours were also more aggressive and deadly. The isolated rats also produced more stress hormones and were more reactive to stressful situations. Rats, like ourselves, are social animals and so being isolated is likely to cause stress.
September 2, 2009 by Evie Bentley.
Research due to be published this autumn in the USA journal Cancer suggests that too much stress can impact on surviving cancer. This study was a meta-analysis of 3.8 million people, cancer sufferers diagnosed between 1973 and 2004. Married people were found to have a 5 year survival rate of 63% compared to a 45% rate for those who were separated. The explanation offered is that the stress of a break-up in a serious relationship interferes with healing and recovery, and hence survival rates. The researchers suggest that the love and support of a partner is a key factor in battling illness, even one as serious as cancer, and their findings are supported by many previous studies. Of course, important other factors are also relevant – how many can you think of?
January 29, 2009 by Cara Flanagan.
We recently received the question above from Claire Matthews of The Castle School in Bristol and thought some of you would be interested in the answer: The SAM system concerns the adrenal medulla and the release of adrenaline/noradrenaline which has the effect of creating physiological (sympathetic) arousal and producing the fight or flight response. The HPA access concerns the adrenal cortex which produces corticosteroids such as cortisol, which help the body to recover after stress but also have negative effects e.g. reduced immune function. Now to the question – do they happen simultaneously or does the SAM system come first and the HPA second?
The answer is both. Essentially both systems are triggered by a stressor but one (SAM) is an instantaneous response like lighting a match, whereas the other (HPA) is much slower and doesn’t happen very easily (like lighting a fire). It is harder to achieve (needs a continuing stressor) and is only activated in more extreme circumstances. So in a sense the HPA response does come second because, even though it is triggered at the same time as the SAM, its response is seen some time later – well after the fight/flight response.