Growth, Self Concept, the Sun and Stress
GROWTH AND SELF-CONCEPT LINKED
IT HAS been revealed that the physical developments and characteristics affects a child’s body image, which is part of his/her self-concept and does not always match with observable reality.
According to Thomas (1990), a child has an internal model shaped not only by direct experience but what they hear from others and their ideas about the current cultural image of an ideal body.
Like all internal models, the body image becomes relatively difficult to change and can affect the child throughout childhood and adolescence – even into adulthood.
Helen Bee, a noted writer in the field of child development writes: "Each young child or teenager has an internal model about what’s ’normal’ and ‘right’ about puberty. Each girl has an internal model about the ‘right age’ to develop breasts and start menstruation; each boy has an internal model about when it is right to begin growing a beard or for his voice to get lower."
The research of scientists like Faust (1983), Lerner (1985, 1987) and Petersen (1987) have revealed that it is the difference between a child’s expectations and what actually happens that determines the psychological effect. If they fall outside expectations, the child or teenager will tend to think less of themselves, may have fewer friends or experience other signs of distress.
For boys, the earlier they start puberty the better it is for them psychologically. They become more confident and their sense of self worth increases when they develop the desired body shape that comes with puberty – with its more muscular and athletic build. Boys score themselves more highly on how early they perceive their pubertal timing rather than the physical timing. The later a boy feel he enters puberty the worse it gets for him psychologically. "It is a linear relationship in the case of boys," Helen Bee said.
It is a different picture for girls, who feel that they are worse off the earlier they enter puberty. For girls, the best time is on time. With a perceived early puberty, they see themselves as too fat and have other negative body images. Late puberty leaves them feeling left out, but the effects do not score as badly as an early puberty. On a graph plotting perceived outcomes against perceived timing of puberty, the girl’s response is a distorted hyperbolic curve with the peak being "at the right time".
Summary of perceived timing of puberty:
Who are well off?
Normally developed girls and early developed boys
Who are worse off?
Early developed girls and late developed boys
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FUN IN THE SUN?
RESEARCH INTO the effect of light on puberty and sexual maturation has revealed a possible role for vitamin D or 1,25-dihydroxycolecalciferol. When light hits the skin, the prohormone cholecalciferol (Vitamin D3) is produced. This can then be converted by the process of hydroxylation to vitamin D in the liver, kidney, placenta and some other sites. Vitamin D is a steroid hormone and together with melatonin secreted from the pineal gland in the brain, they provide a complimentary regulatory system integrating daily and seasonal variations of darkness and light with reproduction.
When there is light, the vitamin D levels increase and melatonin decreases. Not surprisingly, in darkness vitamin D decreases and melatonin increases.
In puberty there seems to be a several fold increase in vitamin D levels which coincides with breast development in girls and pubic hair development in boys. Melatonin levels also fall to match the rise in vitamin D levels.
Studies in the USA, Japan and Holland have discovered that menarche (a girl’s first menstruation; pronounced ‘men-ark-kee’) occurs most frequently in spring and summer and least in autumn and winter. There is also a corresponding increase in conceptions during the spring equinox.
Unfortunately, the mechanism of action of vitamin D is still not well understood, but if it acts like the other steroid hormones, it may provide a way to organise biological rhythm during development. "It’s simple really," said one biologist, "It would be logical to adjust the reproduction to the best seasonal conditions so that it gives the greatest chance for a new generation to survive.
"This may also give us some clue into why we get more randy during the hot summer months!"
"I didn’t fail 800 times, I just found 800 ways it didn’t work."
- Thomas Edison on being accused of failing to make a light-bulb
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Stress can make kids short
Social pack review
The paper "A new stress-related syndrome of growth failure and hyperphagia in children, associated with reversibility of growth-hormone insufficiency" by Straus et al is all about a disorder where children don’t grow properly because of behavioural disturbance and psychosocial stress.
If you take these children away from the stress, they grow properly. Then when they’re stuck back into their old environment, they stop growing again. Why? They seem to produce less growth hormone (GH) – some connection between stress and the hypothalamus.
What sort of stress?
This includes emotional, sexual and physical abuse, neglect, marital conflict and serious parental difficulties.
The term ‘psychosocial short stature’ describes this but there haven’t been any clinical criteria to help doctors to actually diagnose the condition. This paper is groundbreaking in that it has been able to define specific behavioural and developmental criteria so that these children can be identified and may benefit from being removed from the stress.
Straus et al call their syndrome ‘hyperphagic short stature’ which separates it from the umbrella term of other stress-induced neurobehavioural and neuroendocrine syndromes e.g. linked with malnutrition. There is characteristic behaviour like hyperphagia (e.g. stealing food, getting food abnormally, gorging and vomiting, food hoarding) and polydipsia (e.g. abnormal pattern of drinking any liquid – usually too much of it or they’re not actually bothered what type of liquid it is!).
Finally, to get some flavour of what the syndrome is about, here are the diagnostic criteria Straus et al came up with:
These features must be present:
Height for age below third population centile with growth failure (Gotta have this to be of ‘short stature’)
Body-mass index in normal range (They’re not underweight/overweight)
Age greater than 2 years (Why? See the other criteria below)
At least one of these symptoms must be present and should reflect a current pattern of behaviour:
Steals food at home and/or school
Gorges and vomits (This happens when there’s plenty of food around)
Two of these symptoms must be present and should reflect a persistent pattern of behaviour:
Wakes up at night and searches for food
Forages for discarded food and rummages for food in bins (Ugghh!)
This information fact-pack is sponsored by:
* The Manchester Valentines Self Help Group
Didn’t receive any Valentine’s cards? Haven’t got any secret admirers? You needn’t suffer alone! Join the Manchester Valentines Self Help Group (MVSHG) and share your feelings with people just like yourself! Medicine has failed to address the psychological impact and the expressive needs of people with no Valentines. MVSHG is here to actively challenge this shortcoming, and welcomes new members!
"I know that there are people who do not love their fellow man, and I hate people like that!"
- Tom Lehrer
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