Previously, I blogged about the possibility that stress that we are not aware of (or ‘unconscious stress’) could play a role in the development of, for example, cardiovascular disease. If we are not aware of things that threaten us– which means we can’t think consciously about them, let alone talk about them – we cannot address or cope with these threats. This may prolong physical stress responses that, in the long run, can be damaging to our health. This idea is discussed further in this theoretical paper by Jos Brosschot.

Measuring unconscious emotions

After the last blog we performed a series of studies to test the hypothesis that stress we are not aware of influences our physical state. Recently we published two experiments in an Open Access journal.

In the first study we showed a group of students four video fragments to elicit happiness, sadness, anger, or no emotion. Before and after the video fragments we measured their conscious emotions by asking them how they were feeling, and their unconscious emotions by giving them a task (the Implicit Positive and Negative Affect Test, IPANAT) from which we inferred emotions without directly asking about them.

In this study we found that the IPANAT was able to measure changes in unconscious emotions, but that these changes were not related to changes in conscious emotions. So the IPANAT seems to be capable of measuring a different aspect of emotion, something we normally cannot report because we are not aware of it: unconscious emotions.

The effects of unconscious stress

In this study we found that the IPANAT was able to measure changes in unconscious emotions, but that these changes were not related to changes in conscious emotions. So the IPANAT seems to be capable of measuring a different aspect of emotion, something we normally cannot report because we are not aware of it: unconscious emotions.

We found that the conscious emotions were not related to the physiological changes measured during the counting task, regardless of whether the participant received negative feedback or not. So the reported emotions did not reflect the participant’s physiological state. However, we did find a relationship between unconscious emotions and physiological changes. More specifically, we found that higher blood pressure during the task was related to higher unconscious negative emotions, and that blood pressure was slower to return to its normal level during recovery when unconscious positive emotions were lower. So, importantly, in the case of these emotions the participants were not aware of, feeling fewer positive emotions was just as important as feeling more negative emotions. Moreover, unconscious emotions appear to play an important role in health-related physiological changes, perhaps even more than conscious emotions.

In short, with this paper we have shown two important things about how we get sick. First, simply asking people about their stress levels is not sufficient. The emotions we are aware of may not be an accurate reflection of how we actually are in physical terms. Second, it is important to look at unconscious positive emotions as well as unconscious negative emotions. When it comes to unconscious emotions, a reduction in positive emotions may be just as detrimental as an increase in negative emotions.

Implications

These results suggest that stress may influence our health without us being aware of it. But there’s another important implication of these findings. Until now, the field of health psychology, in research and clinical practice, has been limited to the subjective responses of participants or patients. We could make considerable progress in detecting vulnerable groups and underlying mechanisms of disease if we extend the current scope of measurements of well-being to include measures that tap into unconscious processes. This might help people to feel better and be more healthy, both consciously and unconsciously.