How Can We Measure Human Oxytocin Levels?

Is oxytocin really the love and trust chemical? Or is it just the hype hormone? A new paper suggests that many studies of the relationship between oxytocin and behaviors such as trust have been flawed. The paper is a meta-analysis just published by Norwegian researchers Mathias Valstad and colleagues. Valstad et al. found that the level of oxytocin in human blood, often used as a proxy measure of brain oxytocin, has no relation to central nervous system oxytocin levels under normal co