The effect of subliminal evaluative conditioning of cognitive self-schema and illness schema on pain tolerance.

BACKGROUND: Cognitive models explaining medically unexplained complaints propose that activating illness-related memory causes increased complaints such as pain. However, our previous studies showed conflicting support for this theory. PURPOSE: Illness-related memory is more likely to influence reporting of complaints when its activation is enmeshed with that of self-related memory. We, therefore, investigated whether inducing this association would cause a stronger decrease in pain tolerance. In addition, we examined whether SFA acted as a moderator of this effect. METHODS: We used subliminal evaluative conditioning (SEC) to induce an association between activated self-related and illness-related memory. Seventy-six participants were randomly assigned to four combinations of two priming factors: (1) the self-referent word "I" versus the nonself-referent "X" to manipulate activated self-related memory and (2) health complaint (HC) words versus neutral words to manipulate activated illness-related memory. Pain tolerance was assessed using a cold pressor task (CPT). RESULTS: Participants primed with the self-referent "I" and HC words did not demonstrate the expected lower pain tolerance. However, SFA acted as a moderator of the main effect of the self-prime: priming with "I" resulted in increased pain tolerance in participants with low SFA. CONCLUSIONS: The current study did not support the hypothesis that associations between activated self-related memory and illness-related memory cause increased reporting of complaints. Instead, activating self-related memory increased pain tolerance in participants with low SFA. This seems to indicate that the self-prime might cause an increase in SFA and suggests possible new ways to promote adaptive coping with pain.

The effects of a positive health priming intervention on somatic complaints.

Somatic complaints are common and form a major burden. Previous studies suggested that such complaints might be increased by 'illness-related memory', for example due to worries about health. In this ambulatory study we tested whether we could decrease somatic complaints through enhancing the activation of health-related memory by a 'positive health'-priming intervention. Forty-three students were randomly assigned to the 'positive health'-group or a control group. Using online measures, participants reported negative affect (NA) and somatic complaints for a period of six days, while each morning performing the priming task. The intervention caused a decrease in somatic complaints but only for participants with low trait NA or low somatosensory amplification. These findings seem to suggest that priming or other interventions directed at activating positive health memory might reduce health complaints, but only in certain subgroups.

Effects of momentary assessed stressful events and worry episodes on somatic health complaints.

Somatic health complaints are extremely common and are responsible for a large part of human suffering and healthcare costs. It has been recognised that psychosocial stress can affect somatic health. According to the 'perseverative cognition hypothesis', stressful events affect somatic health because people keep on worrying about them. Worry would prolong stress-related physiological activity that can ultimately lead to health problems. In this ambulatory study we tested whether stressful events and worry predict daily somatic complaints, and whether worry mediates the effects of stressful events. In addition, it was tested whether these effects were independent from negative affect. Using electronic diaries, 69 teachers (age 21-60 years) from Dutch primary and secondary schools reported daily stressful events, worry episodes, negative affect and somatic complaints for a period of 6 days. Results showed that worry intensity predicted the number of somatic complaints and mediated the effect of stressful events on somatic complaints. Furthermore, these results were independent from biobehavioural variables and daily negative affect. These findings support the perseverative cognition hypothesis proposing that the negative somatic health effects of stressful events are largely due to the worry; that is, to the prolonged cognitive representation of stressors.

Decreasing pain tolerance outside of awareness.

OBJECTIVE: Medically unexplained symptoms (MUSs) are a humanitarian and economic burden. Among them, pain complaints without organic pathology are the most prevalent. Theoretically, activated illness-related memory may cause reporting of symptoms by changing perception and interpretation of bodily signals to the extent that they are not tolerated and become complaints. We tested whether activating illness-related memory without conscious awareness leads to decreased pain tolerance (PT). METHODS: Activation of illness-related memory without conscious awareness was manipulated by a subliminal priming technique. Eighty participants were randomly assigned to four conditions, with prime words describing either (a) health complaints (HCs), to activate an illness-related memory, or three control categories: (b) neutral content, (c) general bodily sensations, and (d) negative valence. The latter two conditions were added to test the alternative hypotheses that reduced PT could be observed with the semantic activation of these two components of HCs. We measured PT using a cold pressor task. RESULTS: Participants who were subliminally primed with HC words reported lower PT compared with participants who were primed with neutral words. Priming with the other words did not lead to significantly different effects relative to priming with neutral words. CONCLUSIONS: The findings suggest that PT can be involuntarily decreased by activating illness-related memory. This implies partial evidence for a crucial element of a cognitive model of medically unexplained symptoms, which holds that chronically activated illness-related memory causes the development of somatic complaints without observable bodily pathology.