Finger length

There are now many studies that show how the relative length of the ring and index fingers, known as the 2D:4D ratio, predict a variety of outcomes including susceptability to prostate cancer, sporting prowess, longevity and sexual orientation. It is believed that it reflects exposure to testosterone shortly after conception.
This newspaper article discusses how it predicts earnings amongst traders in the City. It would be interesting to see how it fares in a human capital model on a representative sample of the population. Since it is relatively easy to measure (as biomarkers go), hopefully it will be incorporated into datasets in the future.

Does Cortisol Help Us To Regulate Our Emotions?

Low levels of the stress hormone cortisol could be linked to antisocial behaviour in adolescent boys, UK researchers say...

An increase in cortisol levels is thought to make people behave more cautiously, and help them to regulate their emotions, particularly their temper and violent impulses.

But (the) Cambridge university study found this did not happen in boys with a history of severe antisocial behaviour.

Read comments from lead researcher Dr. Graeme Fairchild on MedIndia.com here.

Substance P at the nexus of mind and body in chronic inflammation and affective disorders

A potentially very interesting serum marker: For decades, research has demonstrated that chronic diseases characterized by dysregulation of inflammation are particularly susceptible to exacerbation by stress and emotion. In recent years, substance P has been implicated in both the pathophysiology of inflammatory disease and the pathophysiology of depression and anxiety by 2 parallel fields of study. This review integrates the literature from these 2 parallel fields and examines the possibility that substance P dysregulation may be a point of convergence underlying the overlap of chronic inflammatory disease and mood and anxiety disorders.

Abstract, Full

Recent article by Andrew Steptoe points to neuroendocrine and cardiovascular correlates of daily affect

Steptoe applies a methodology which he perfected studying the positive psychobiological effects of a good cuppa to show that positive emotion, like tea, has many positive effects and can guard against stress. This study uses ecological momentary assessment (EMA) whereby mood is assessed using rating scales at four periods throughout the day. They also use a stress test to evaluate cardiovascular reactivity and then relate this to affect throughout the day. Having a high level of positive affect througout the day means that you have lower levels of systolic BP at rest and after the stress task and also quicker diastolic BP recovery. Interestingly, having low positive affect was predictive of a greater cortisol response and this effect was independent of negative affect. Those who were high in positive affect did not differ from those low on positive affect in terms of negative affect indicating that they are separable concepts rather than existing on a continuum from negative to positive. Positive emotion aslo has independent effects indicated that merely focusing on removing ill-being is not enough.

This article pre-empts what will be quite a significant piece of work when the bloods from this study come back to show relationships between daily mood and a variety of measures of immune function, inflammation, and neuroendocrine function. They did not, however, include cardiovascular measures across the day. Steptoe seems to prefer to examine stress in the laboratory and relate this to daily affect. Coupling both methodologies would be worthwhile. The DRM may offer advantages over EMA and incorporating both into a study and seeing their level of similarity may be worthwhile.

Overall, demonstrating a protective effect of positive emotion on biological stress hormones which is independent of age, BMI, or importantly negative affect is a valuable finding which needs to be replicated in a larger sample.


Neuroendocrine and cardiovascular correlates of
positive affect measured by ecological momentary
assessment and by questionnaire

Assessment of biological function in psychosocial research on health

In this chapter entitled "Tools of psychosocial biology in health care research" Andrew Steptoe outlines the main types biological measurements which should be included in psychosocial research on health. The review points to the importance of "non-specific biological markers of stress-related activation or resistance to disease". Biological measures which fall into this category include: (1) neuroendocrine factors such as cortisol, the steroid hormones DHEA and DHEA sulphate, the catechlomines adrenaline and noradrenaline, and insulin-like growth factor and gonadal hormones such as testosterone and oestrogen, (2) cardiovascular measures such as blood pressure (author recommends self-measurement as a more cost-effective alternative to ambulatory monitoring systems), and measures of heart rate variability, (3) measures of inflammation such as C-reactive protein, fibrinogen and the proinflammatory cytokines IL-6 and tumour necrosis factor a (TNFα), (4) measures of immune function such as T cells, cytotoxic T cells, B cells, natural killer cells can be made via blood or saliva sample, (5) musculoskeletal problems which can be assessed via self-report, physical examination, or through surface electromyography (EMG). Sweat gland activity and forced respiratory volume are also discussed in brief. Steptoe also suggests that combining biological measures with mental stress testing and naturalistic monitoring is a useful advance in evaluating the extent to which individual differences in acute stress reactivity generalize to everyday life situations.

see also Psychobiological Processes: Pathways Linking Social Factors with Disease a presentation by Steptoe which includes a model of where brain, neuroendocrine, autonomic and immune responses fit into the relationships between social structure various other factors (work, social environment, genes, health behaviours) and well-being.