The body has a built-in pain regulation system and it’s very powerful
Pain evolved as a means of motivating organisms to act to protect injuries and promote healing. The short and grim lives of those rare individuals born without the ability to feel pain is a powerful reminder of the importance of pain to survival (Diatchenko, Nackley, Tchivileva, Shabalina, & Maixner, 2007). Yet unfettered, pain would be ...
Real time measurement
A vast amount of psychology related research consists of asking people about the past: how they felt, what they thought, what they did, and why they did it. The problem with this very common strategy is that human memory is notoriously flawed. It’s flaws and biases have been widely documented. Perhaps even worse and more insidious ...
Salivary alpha amylase
In the presence of a physical or psychological threat, the body reacts with a coordinated series of measures aimed at maintaining homeostasis. This response consists mainly of activity in two systems: the sympathetic adrenomedullary (SAM) system and the hypothalamic-pituitary-adrenocortical (HPA) axis (Herman, and Cullinan, 1997; Tasker and Harman, 2011; Kirschbaum and Hellhammer, 1994). The SAM ...
Heart rate variability
Although it appears to beat at a fairly regular pace, the speed with which the heart beats is in fact quite variable. Over the course of a minute, heart rate variability can spike and fall numerous times. This variability reflects changes in autonomic nervous system activity and can be affected by respiration, movement, and psychological ...
Multilevel modeling: A primer
A remarkable range of phenomena of concern to researchers in many fields are often hierarchical (or nested) in nature. Patients are nested within doctors. Employees are nested within teams. Students are nested within classrooms (each of which has a different teacher), which are in turn nested within schools, family members within families. In addition repeated ...
Salivary cortisol: A viable option for objectively measuring acute stress responses
What is cortisol? Cortisol is a steroid hormone, a glucocorticoid produced in the zona fasciculata of the adrenal cortex. It is released in response to stress and a low level of blood glucose. Its effects in the body are remarkably wide ranging, including the alteration of immune function, the inhibition of insulin utilization, and stimulating ...
Volunteering makes people feel more productive
Swiss researchers recently conducted a survey 746 workers in which participants were asked about paid job demands, volunteering, perceptions of work-life balance, resources, and health and wellbeing outcomes. Health outcomes included a measure of burnout, stress and stress symptoms, psychological and social wellbeing, and work engagement. They found that after controlling for variability across participants in job ...
The test comes back positive. Now what?
You receive the mammography test results for a patient. She tested positive. What are the chances that she in fact has cancer? What do you tell your patient? The necessary statistics are available to help doctors make exactly these types of determinations. Probability that a woman has breast cancer, P(cancer) is 1%. This the prevalence of ...
What does statistically significant mean and what doesn’t it mean?
At a recent statistics workshop I was conducting to a group of medical students I asked how many could define statistically significance. Everyone had heard of it and knew that p < .05 constituted a statistically significant effect, but no one really understood what it meant. To understand what it means, it is crucial to remember that ...
The anchoring bias: The powerful pull of first impressions
In an early experiment by Daniel Kahneman and Amos Tversky, participants were asked to compute the product of a series of numbers in 5 secs. But in one group the series was ascending, 1 x 2 x 3 x 4 x 5 x 6 x 7 x 8 whereas in the other it was descending: ...
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