The term Emotion in physiology is referred to an alteration of the internal psychophysiological state as reaction to an external event or situation.

This definition already links this concept to the neurophysiological dimension: one century ago it was already clear that “measures as skin resistance, heart rate, blood pressure, blood flow, skin temperature, blood-oxygen saturation, gastric motility, pupillary diameter, etc. have been shown to be remarkably sensitive and responsive measures in a variety of emotional states” (Lacey and Lacey, 1958).

Nowadays, different neurophysiological correlates of emotional variations have been proposed, such as heart activity (Lane et al., 2019), skin sweating (Levenson, 2003), respiration (Philippot et al., 2002). However, it remains difficult to categorise these correlations in relation to specific emotions.

BrainSigns addressed this concern by retrieving the psychological model of emotions suggested by Russel (1980), namely the “Circumplex plane of affects”. Russel placed 8 main emotions on a circle living on a Cartesian plane, whose two orthogonal dimensions were the valence (x-axis) and the arousal (y-axis). Since it has been proved that Heart Rate is highly correlated with Valence, while Skin Conductance with Arousal (Bradley and Lang, 2000), Vecchiato and Babiloni (Vecchiato et al., 2014) suggested to merge these two physiological data to obtain a synthetic indicator of emotional response, the emotional index, providing evidence of the insightfulness of this index.

Today, this index is successfully used in BrainSigns to assess the emotional experience of users when watching advertising contents, or in a shop journey, or while visiting a museum, or in other situations where the emotional dimension plays a key role in the user experience (Cherubino et al., 2015; Martinez Levy et al., 2022).

REFERENCES

• Bradley, Margaret M., and Peter J. Lang. "Emotion and motivation." Handbook of psychophysiology 2 (2000): 602-642.
• Cherubino, Patrizia, et al. "Measuring cognitive and emotional processes in retail: A neuroscience perspective." Successful technological integration for competitive advantage in retail settings. IGI Global, 2015. 76-92.
• Lacey, John I., and Beatrice C. Lacey. "Verification and extension of the principle of autonomic response-stereotypy." The American journal of psychology 71.1 (1958): 50-73.
• Lane, Richard D., et al. "Neural correlates of heart rate variability during emotion." Neuroimage 44.1 (2009): 213-222.
• Levenson, Robert W. "Blood, sweat, and fears: The autonomic architecture of emotion." Annals of the New York Academy of Sciences 1000.1 (2003): 348-366.
• Martinez-Levy, Ana C., et al. "Message framing, non-conscious perception and effectiveness in non-profit advertising. Contribution by neuromarketing research." International Review on Public and Nonprofit Marketing 19.1 (2022): 53-75.
• Philippot, Pierre, Gaëtane Chapelle, and Sylvie Blairy. "Respiratory feedback in the generation of emotion." Cognition & Emotion 16.5 (2002): 605-627.
• Russell, James A. "A circumplex model of affect." Journal of personality and social psychology 39.6 (1980): 1161.
• Vecchiato, Giovanni, et al. "How to measure cerebral correlates of emotions in marketing relevant tasks." Cognitive computation 6 (2014): 856-871.