Sequential unfolding of novelty and pleasantness appraisals of odors: Evidence from facial electromyography and autonomic reactions.

Abstract

We investigated the effects of odors on appraisal processes and consequent emotional responses. The main goal was to test whether an odor is detected as novel or familiar before it is evaluated as pleasant or unpleasant. Participants performed a recognition task in which they were presented with pairs of unpleasant or pleasant odors (sample and target odors). Within a pair, the sample and target were either identical or different to assess participants' novelty detection; unpleasant and pleasant target odors were contrasted to examine participants' appraisal of intrinsic pleasantness. We measured facial expressions using electromyography and physiological reactions using electrocardiogram and electrodermal activity in response to odors. The earliest effects on facial muscles and heart rate occurred in response to novelty detection. Later effects on facial muscles and heart rate were related to pleasantness evaluation. This study is the first to demonstrate the existence of a sequence of appraisal checks for odors eliciting emotional reaction.

Understanding the Mechanisms Underlying the Production of Facial Expression of Emotion: A Componential Perspective

“…In the Delplanque et al (2009) odor study, the authors found an increase in muscle activity over the forehead region for novel stimuli, in comparison to familiar stimuli, at about 100 ms after the presentation of the stimulus. In contrast, the effect of pleasantness on frontalis and corrugator was observed about 500 ms after the presentation of the stimulus, supporting the hypothesized sequence of appraisal checks.…”

“…Results showed that the two appraisals affected activity of the facial muscles in accordance with CPM predictions: Activity in the cheek region was higher for pleasant stimuli and goal conducive events; activity in the brow region was higher for unpleasant stimuli and obstructive events. Delplanque et al (2009) presented pleasant or unpleasant odors that were either novel or familiar to the participants and investigated physiological and facial reactions to appraisals of novelty and intrinsic pleasantness. The results showed a highly significant increase in the activity of muscle over the forehead region (frontalis) for novel stimuli and over the forehead and brow region (corrugator) for unpleasant stimuli.…”

Advocating a Componential Appraisal Model to Guide Emotion Recognition

“…EMG studies found that: a) the activity of the Scherer, , 2010. corrugator supercilii (the muscle whose activity produces frowning, Action Unit 4 using the notation of FACS; Ekman & Friesen, 1978) was correlated with appraisals of perceived obstacle and motivational incongruence (Pope and Smith, 1994;Smith, 1989), as well as with goal obstructive events and unpleasant stimuli (Aue, Flykt, & Scherer, 2007;Aue & Scherer, 2008;Delplanque et al, 2009); b) the activity of the zygomaticus major (the muscle whose activity pulls the corners of the lips up, i.e., smile, Action Unit 12 using FACS notation) was associated with the appraisal of subjective pleasantness and with goal conducive events (Aue et al, 2007;Aue & Scherer, 2008); and c) the activity of the frontalis (the muscle whose activity pulls the eyebrows up -Action Units 1 and 2 using FACS notation) was higher for novel stimuli than for familiar stimuli. In a recent study Mortillaro, Mehu, and Scherer (2011) tested the plausibility of an appraisal approach as a way to distinguish facial expressions of different positive emotions.…”

Evaluating Industrial Products in an Innovative Visual-Olfactory Environment

“…This is related to the fact that after a smell is experienced and associated in our memory with a specific emotional experience, it is able to evoke the associated emotion when later encountered [20]. Also, researches demonstrated that smells can impact on physiological parameters, such as heart rate or skin conductance, and consequently can induce activation or relaxation states in people [4,21].…”