Physical Warmth promotes Interpersonal Warmth

In an amusing study by LE Williams and JA Bargh, published in Science in 2008, subjects exposed to warm objects behaved in a manner which was more interpersonally warm. Here is the reference:
http://www.ncbi.nlm.nih.gov/pubmed/18948544

In the first experiment described by the authors, subjects in the elevator on the way to the study lab were asked to hold an experimenter's drink cup for a moment, while the experimenter wrote some identifying information down on a clipboard. The experimenter in the elevator did not have knowledge of the study's hypotheses. In the study lab afterward, the subjects were given a brief written description of a person (the same description given to all subjects), and were asked to rate that person in terms of a variety of personality dimensions. The subjects who briefly had held a cup of hot coffee gave personality ratings that were significantly "warmer," compared to the subjects who had held a cup of iced coffee. The ratings for warmth were 4.71 out of 7 for the "hot coffee" group, compared to 4.25 out of 7 for the "iced coffee" group; these differed with a p value of 0.05. "Warmth" in this sense refers to traits such as friendliness, helpfulness, and trustworthiness.

The second experiment was more blinded, in that the experimenters did not know whether the subjects were handling a warm or cold object. This time, subjects were offered a choice of two types of gifts after the experiment: the first type would be for personal use, the second would be a gift for a friend. Those who had handled a warm object were substantially more likely to choose a gift for a friend, rather than for themselves.
Those who had handled a cold object chose a "selfish" gift 75% of the time.
Those who had handled a warm object chose the "selfish" gift 46% of the time.

The authors discuss attachment theory, and suggest that one explanation for these findings, on a neurobiological level, is that the insular cortex in the brain is responsible for processing information about both physical and psychological warmth, therefore the two types of warmth perception may influence each other.

I find this type of cross-sectional social-psychological research fun and a bit lighthearted, but often containing kernels of wisdom.

It would be interesting to do similar studies of this sort, but with different groups of subjects who are stratified according to interpersonal style, depressive symptoms, etc. Perhaps there are subjects who are most sensitive to these environmental effects.

I'm amused and delighted, in any case, that figurative or "metaphorical" warmth seems to match up with literal or physical warmth. A nice meeting of the metaphorical with the literal. Perhaps this is typical of what the brain does.

In any case, this little piece of evidence further supports the recommendation to do sensually pleasing, "warmth-oriented" activities, as part of a regimen for maintaining psychosocial health. There may be something in particular about heat which could be therapeutic. Hot baths are anecdotally helpful for relaxation, pain relief, and to promote deeper sleep. I've encountered a few examples in which people found saunas quite helpful for seasonal depressive symptoms. Maybe a very warm, cozy sweater can be helpful for your mental health, and even have positive effects on others!

Here are references to a few studies showing improvement in insomnia following hot baths:
http://www.ncbi.nlm.nih.gov/pubmed/10566907 {a 1999 study from the journal Sleep, showing improvements in sleep continuity and more slow-wave sleep earlier in the night, in older females with insomnia who had 40-40.5 °C baths 1.5-2 hours before bedtime}
http://www.ncbi.nlm.nih.gov/pubmed/15879585 {a 2005 study in the American Journal of Geriatric Psychiatry showing improved sleep in elderly people with vascular dementia, following 30 minute baths in 40°C water, 2 hours before bedtime}

A precipitant of some seasonal depression, at least in Canada, may be not only the darkness but the cold. The cold may lead not only to a disinclination to go outside, but also to a less generous or a "colder" interpersonal stance, which would further perpetuate a depressive cycle. This is another reason to heed that advice mothers often give young children, to dress warmly in the winter.

Here is a link to the abstract of a study from Japan, published in Psychosomatic Medicine in 2005: http://www.ncbi.nlm.nih.gov/pubmed/16046381

In this study, mildly depressed subjects were randomized to receive one of two treatments, 5 days per week, for 4 weeks, in addition to daily physical and occupational therapy:
1) "thermal therapy" in a 60 °C sauna for 15 minutes, followed by 30 minutes wrapped in a blanket, in a 28 °C room.
2) "non-thermal therapy" of 45 minutes in a 24°C room

The thermal therapy group had a 33% reduction in psychological symptoms, compared to a 14% reduction in the non-thermal therapy group.
The thermal group had a 42% reduction in somatic complaints, compared to an 8% reduction in the non-thermal group.

The research literature on this subject is quite limited, but there is some evidence that warmth--physical and psychological--is therapeutic!

Chocolate & Stress

This is a sequel to one of my previous posts:
http://garthkroeker.blogspot.com/2008/10/chocolate.html

A recent study looked at various hormonal and metabolic changes associated with consuming chocolate. In this case, 30 people were given 40 g of dark chocolate daily for 2 weeks. The authors conclude that the chocolate consumption was responsible for reducing metabolic changes associated with stress, including cortisol and catecholamine excretion.

Weaknesses of the study include its brief, non-randomized, non-blinded nature (mind you, many of us would not easily be fooled by a placebo chocolate substitute!). And I see that the study is associated with the "Nestle Research Centre" in Switzerland. While I am pleased to know that a large chocolate company has a "research centre," I do have to wonder if there could be a higher risk of bias at play.

Here's a link to the abstract:
http://www.ncbi.nlm.nih.gov/pubmed/19810704

In the meantime, there is a variety of evidence out there that chocolate consumption in moderation is good for your health, in a variety of ways.

However, one concerning issue I just learned about has to do with lead contamination in cocoa and chocolate products. Lead is a heavy metal poison which should not have any presence in the diet. It can have widespread toxicity, particularly affecting the nervous system, through either acute or chronic exposure. The issue of lead in chocolate is discussed in mainstream research, such as by Rankin & Flegal (references:http://www.ncbi.nlm.nih.gov/pubmed/16757407, http://www.ncbi.nlm.nih.gov/pubmed/16203244). Based on some of this research, it may be true that raw, unprocessed cocoa nibs have no significant lead contamination, rather the lead in some cocoa and chocolate products may be the result of industrial processing.

Hopefully, manufacturers can address this issue, so that we can be reassured about safety, and so that we can get on with the enjoyment of one of life's great pleasures, knowing that it, in moderation, may also be good for psychological and medical health.

Why Cats Paint

Why Cats Paint: A Theory of Feline Aesthetics by Heather Busch & Burton Silver.

I find this book a masterpiece of humour, a wonderful parody of art criticism, and also a simple entertainment for those of us who enjoy pets.

Have a look at the customer review comments from Amazon:
http://www.amazon.com/exec/obidos/ASIN/0898156122/qid=1005224759

More evidence about the impact of nutrition on mood

An important paper was just published by Akbaraly et al. in The British Journal of Psychiatry, in which 3486 people were followed prospectively for 5 years, with an analysis of nutritional habits and depression symptoms. Here's a link to the abstract:
http://www.ncbi.nlm.nih.gov/pubmed/19880930


The data showed that individuals consuming a diet rich in "processed foods" (such as sweetened desserts, fried food, processed meat, refined grains, and high-fat dairy products) had a much higher rate of depression compared to those consuming a diet heavily loaded with vegetables, fruits, and fish.

The analysis controlled for confounding factors such as gender, age, caloric intake, marital status, employment grade, education, smoking, physical activity, hypertension, diabetes, and cardiovascular disease. A component of the analysis also strongly suggests that the association is not due to reverse causation, of depression leading to worse nutrition. Rather, the analysis strongly suggests that poor diet is a component of causation: that is, poor diet directly increases the risk of becoming depressed, or of having worse depressive symptoms.

Those in the third of people with diets highest in processed foods had a 58% higher chance of having clinical depression compared to the third of people with the healthiest diets.

So, once again, more evidence-based advice to eat healthily in order to protect your mental health:
-more vegetables, fruits, and fish
-less sweets, fried foods, white flour, whole milk, ice cream, etc.

Memory Games

Here are a few links to some free memory games. They may be directed towards children, but I think people of any age could find them useful or fun exercises to improve attention & memory (or even better: you can devise your own memory games, to play with a friend, away from a computer screen):

http://faculty.washington.edu/chudler/chmemory.html
http://www.kidsmemory.com/memory_face_off/face_up_memory_game.php
http://www.kidsmemory.com/light_it_up/light_it_up_memory_game.php
http://www.kidsmemory.com/number_scrambler/index.php
http://users.netrover.com/~kingskids/memory.htm