Year: 2007

Scientific American has a short article which examines whether there’s any truth to the common theory that stress makes your hair go grey. It’s turns out there’s some circumstantial evidence that stress may have an effect, but no definite causal link has been found.

Apparently, the gradual loss of melanocyte stem cells, ones that are key for hair colouring, lead to the loss of pigment.

Does stress accelerate this demise of the melanocyte population? “It is not so simple,” Fisher says, noting that the process of graying is a multivariable equation. Stress hormones may impact the survival and / or activity of melanocytes, but no clear link has been found between stress and gray hair. Suspicions ‚Äî and hypotheses ‚Äî abound, however.

“Graying could be a result of chronic free radical damage,” says Ralf Paus, professor of dermatology at the University Hospital Schleswig-Holstein in L√ºbeck, Germany. Stress hormones produced either systemically or locally (by cells in the follicle) could produce inflammation that drives the production of free radicals ‚Äî unstable molecules that damage cells ‚Äî and “it is possible that these free radicals could influence melanin production or induce bleaching of melanin,” Paus says.

“There is evidence that local expression of stress hormones mediate the signals instructing melanocytes to deliver melanin to keratinocytes,” notes Jennifer Lin, a dermatologist who conducts molecular biology research at the Dana-Farber / Harvard Cancer Center in Boston. “Conceivably, if that signal is disrupted, melanin will not deliver pigment to your hair.”

And general practice physicians have observed accelerated graying among patients under stress, says Tyler Cymet, head of family medicine at Sinai Hospital in Baltimore, who conducted a small retrospective study on hair graying among patients at Sinai. “We’ve seen that people who are stressed two to three years report that they turn gray sooner,” he says.

Link to SciAm article ‘Fact or Fiction?: Stress Causes Gray Hair’ (via 3Q).

Cognitive Daily discusses the findings of two interesting studies that suggest that simply seeing the colour red makes us perform worse on tests.

The articles discuss a couple of elegant studies by a research team, led by psychologist Andrew Elliot, which confirmed that seeing red makes us tend to do worse on tests. They then set about trying to understand why.

In a second study, students were given test booklets with the title in one of several possible colours. Interestingly, those who had booklets with red titles tended to choose easier questions, which led to a direct test of a neuropsychological idea about brain symmetry and avoidance:

Students who saw the red test cover chose significantly more easy test questions than either those who saw green or gray test covers. There was no significant difference between the students who saw green and gray.

So it seems that the color red in this context may cause people to avoid challenging or difficult situations. In their final experiment, the researchers took advantage of a robust experimental finding about avoidance. For more than two decades, nearly a hundred studies have found a characteristic brain activity associated with avoidance — asymmetrical activity in the right frontal cortex. This is easily measured using non-invasive EEG equipment.

The research team used exactly this technique and found that relatively greater right hemisphere was found for red material, but not other colours, suggesting red triggers part of the avoidance system.

As Cognitive Daily note, we can’t tell from these experiments whether the red and avoidance link is with us from birth, or whether we’ve just learnt it through cultural exposure.

It’s a really elegant couple of studies though, and as always, they’re wonderfully explained by the CogDaily team.

Link to ‘Does the color red really impair performance on tests?’.
Link to ‘Why does seeing red make test-takers choke?’

The New York Times has a brief but wonderfully illustrated article on the cultural history of absinthe, the highly alcoholic spirit that was adopted by numerous famous artists.

Wikipedia also has a fantastic article on absinthe which looks at the history of its creation, popularity, prohibition and revival.

It also exposes the myth that wormwood, a key flavouring ingredient, causes hallucinations. A scientific article looked at the evidence for this and found that the effects of the drink are almost entirely due to its alcohol content.

While thujone, an active ingredient in wormwood, can causes seizures in high enough quantities, there isn’t enough in absinthe to have a significant effect.

However, erroneous concerns about the drink leading to dangerous forms of ‘madness’ led it to be banned in most European countries in the early 1900s, giving it an instant notoriety and cultural impact that far goes beyond its pharmacological influence.

Link to NYT on ‘Absinthe Returns in a Glass Half Full of Mystique…’
Link to Wikipedia article on absinthe.
Link to scientific article ‘Absinthism: a fictitious 19th century syndrome…’

From a footnote on p282 of Oliver Sacks Musicophilia:

There have been very few systematic studies of music in dreams, though one such [pdf], by Valeria Uga and her colleagues at the University of Florence in 2006, compared the dream logs of thirty-five professional musicians and thirty non-musicians. The researchers concluded that “musicians dreams of music more than twice as much as non-musicians [and] musical dream frequency is related to the age of commencement of musical instruction, but not to the daily load of musical activity. Nearly half of all recalled music was non-standard, suggesting that original music can be created in dreams.” While there have been many anecdotal stories of composers creating original compositions in dreams, this is the first study to lend support to the idea.

The finding has an interesting parallel with findings on the ‘age-of-acquisition effect’ in language research.

It was known for years that things like the ability to name objects or remember words was influenced by the how common the word is, and how ‘concrete’ it is. For example, concrete words like tree, apple and house tend to be more robust than abstract words like hope, love or like.

Largely due to the work Andy Ellis it’s been found that many of these effects are actually a function of at what age the word was first learnt, with earlier words being more robust in terms of being more easily processed or accessed during cognitive processing.

The Uga study hints that a similar process may be at work with music.

Link to PubMed entry for study on music and dreams.
pdf of full-text of music and dreams study.
Link to Google Scholar search for age-of-acquisition effect.

The editorial of the Journal of the National Cancer Institute discusses a recent study that found that hypnosis can be successfully used in breast cancer surgery to reduce pain, nausea, painkiller use, tiredness and emotional impact of the surgical procedure.

The study was a randomized controlled trial of patients who were undergoing breast surgery either to treat a cancer or to test a lump to see if it was cancerous.

Patients were randomly assigned to either a brief 15-minute hypnosis condition, or to another where the patient discussed their concerns with an empathic psychologist (to make sure the effects weren’t just due to having someone their to ‘calm their nerves’).

The study found that patients given hypnosis needed less painkilling medication, were less nauseous, less emotionally upset, and experienced less pain intensity than the patients in the ’empathic listening’ condition.

The editorial notes that the results suggest hypnosis is a powerful tool for helping patients, discusses why it isn’t being used more widely, and what we know about how it affects the brain:

Thus, the study in this issue contributes to an impressive body of research using randomized prospective methodology in sizeable patient populations to demonstrate that adjunctive hypnosis substantially reduces pain and anxiety during surgical procedures while decreasing medication use, procedure time, and cost. If a drug were to do that, everyone would by now be using it.

So why don’t they? For one thing, there is no mediating industry to sell the product‚Äîdangling watches are out of fashion for hypnotic inductions. Plus, there is still lingering suspicion that hypnosis reeks of stage show trickery. After all, the magic wand originated with Mesmer’s use of a magnetic stick to presumably alter magnetic fields in patients’ bodies. Yet hypnosis is the oldest Western form of psychotherapy. Hypnosis is a state of highly focused attention, with a constriction in peripheral awareness and a heightened responsiveness to social cues. It is most similar to the everyday state of becoming so absorbed in a good movie or a novel that one enters the imagined world and suspends awareness of the usual one, a condition playwrights refer to as the “suspension of disbelief.” This state can exert powerful influence on mind and body.

Altering perception using hypnosis results in brain changes that literally reduce pain perception [rather than merely altering the response to pain]. Indeed, simply changing the wording of the hypnotic instruction from “you will feel cool, tingling numbness more than pain” to “the pain will not bother you” alters the brain location of the analgesia from the somatosensory cortex to the anterior cingulate gyrus. Hypnotic alteration of color perception results in bidirectional changes in blood flow in the portions of the visual cortex that process color vision‚Äîblood flow in this region increases when color is imagined rather than seen and decreases when color is hypnotically drained from a colorful stimulus. Thus, there is good neurophysiologic reason to believe that hypnosis is potentially a powerful tool to alter perception of pain and associated anxiety.

If you’re interested in volunteering for research into the neuropsychology of hypnosis in London (which doesn’t involve anything painful!), we’re still recruiting participants for sessions at 2pm on Saturday 17th and 24th November.

There’s more information at our study web page.

Link to Journal of the National Cancer Institute editorial on hypnosis.
Link to abstract of RCT study.
Link to information on our neuropsychology of hypnosis study.

ABC Radio National’s All in the Mind just had a programme looking at both the neuroscience of meditation and its increasing use in evidence-based mental health treatments.

Key aspects of meditation are increasingly become adopted into well-researched mainstream cognitive therapies.

Essentially, it’s Buddhist mindfulness meditation, repackaged to make it sound more palatable to a wider audience, and often included alongside more traditional approaches.

The two big players in the psychological treatment field at the moment are Mindfulness-based CBT and Acceptance and Commitment Therapy.

Mindfulness approaches seem particularly useful for people with chronic or relapsing symptoms, such as severe relapsing depression, rather than for first-episode or acute conditions.

For example, a key study published in 2000 found that mindfulness-based CBT had a beneficial effect on people who had three or more relapse of depression, but not people who had experienced two relapses or less.

The idea is quite different from cognitive approaches, where clients are encouraged to identify, evaluate and retrain their problematic thoughts and behaviours.

Mindfulness instead encourages people to be fully aware of these troublesome thoughts or sensations, but not to engage with them.

In other words, clients are encouraged to develop a degree of separation from their thoughts and emotions, so they can experience them, but not feel that they are fully controlled by them.

Some research has suggested that this is because mindfulness (and indeed other approaches) improve our ability to monitor, evaluate and engage with our own thoughts – so-called metacognitive ability.

Link to AITM on ‘Dr Mindfulness: science and the meditation boom’.