The study is part of the project ‘Craving and alimentary disorders: Assessment instruments and psychophysiological mechanisms’, by Sonia Rodríguez Ruiz, a researcher of the Department of Personality, Assessment and Psychological Treatment of the Universidad de Granada, and deals with the assessment of the psychophysiological mechanisms underlying craving for chocolate. The term craving refers to the “an intense desire for some particular substance”.
According to the researcher, the predictive capacity of the cravings for food as regards alimentary disorders makes their knowledge a useful tool to understand better compulsive consumption, eating huge amounts of food in nervous bulimia or the early abandonment of the treatments to lose weight in obese persons.
72 women healthy students aged 18 to 23, selected according to their punctuations in the questionnaire Food Craving Questionnaire-Trait adapted to chocolate, participated in the study. Once they were selected they were subjected to test consisting of the visualization of images with a different emotional content: pleasant, unpleasant, neutral and specific of chocolate.
In order to study corporal emotions and reactions during the test, they carried out peripheral measures of the autonomous nervous system. By means of sensors they registered the electric signals produced by the body: blood pressure, heart rate, breathing, conductance (skin sweating) and blinking. During the projection of the images, they presented a white noise to the participants to evoke the defensive reflexes, the heart response and the motor reflex for start (blinking). This test has been completed with the subjective assessment of the participants through three more questionnaires.
Result of the tests
The results show that, in the high craving group, both the appetitive motivational system and the defensive motivational system are activated to a greater degree in front of unpleasant and chocolate slides, than in the low craving group.
Contrary to what they thought, the high craving group increased the magnitude of the start motor reflex (blinking) and the conductance response (skin sweating) in front of the chocolate slides, in comparison with the low craving group. According to Sonia Rodríguez, it suggests that in the high craving group, during the start tests and in front of the chocolate slides, the defensive motivational system was activated in stead of the appetitive one, to a greater extent that in the low craving group.
The punctuations in the subjective reactivity questionnaire in front of the chocolate slides showed that the participants of the high craving group declared that they felt happier, more involved and motivated and, at the same time, more anxious, unable, vulnerable and guilty than the low craving group. According to Sonia Rodríguez, chocolate slides produced ambivalent feelings in the high craving group, this is, an “appetitive-aversive conflict” or a “motivational approach-avoidance conflict”. According to the researcher, it can be due to the cultural, social and mental influences, tastes and habits.
Reference: Sonia Rodríguez Ruiz. Department of Personality, Assessment and Psychological Treatment. Phone number: 958 244 251 – 244251. E-mail: srruiz@ugr.es
