Passive Viewing of Emotional Stimuli: An fNIRS-EEG Study


  • Teja Štrempfel University of Ljubljana



With the latest debates in affective neuroscience on how emotions are organised in the brain, an increase in the number of neuroimaging studies of emotion processing can be detected [1]; specifically studies using the relatively young method of functional near infrared spectroscopy (fNIRS) [2]. However, these sorts of research studies differ immensely in the type of tasks and stimuli used to evoke emotions in their participants (from using written sentences to listening to specific emotional prosodies), which affects direct comparison of the results.

Moreover, focusing on studies that used visual stimuli (static pictures), we notice that little research has employed neuroimaging methods to study specific emotions; in most cases, labels “pleasant” and “unpleasant” are used to describe the valence of the emotion stimuli, but there is no clear indication if these stimuli correspond to discrete emotions like fear, anger and disgust [3]. In an up-coming study, we use different emotional contexts as examples to validate studying the brain basis of emotions by simultaneously using fNIRS and electroencephalography (EEG).


In the present study we apply a multi-modal neuroimaging method of combining hemodynamic and electroencephalographic measures in an experimental block design. During the measurements, participants will be presented with diverse emotional visual stimuli (disgust, anger, fear, happiness, sadness and neutral) obtained from the International Affective Picture System collection (IAPS) to evoke corresponding emotional responses. Post evaluation of the same stimuli’s valence and arousal will follow.

Expected results

The new-found results are expected to resemble the findings of previous studies [2][3], which indicate the lateralization of the prefrontal cortex (PFC) based on stimulus valence (pleasant – unpleasant); the left PFC was more active in regards to positive or pleasant stimuli, whereas the right PFC corresponded to negative or unpleasant stimuli. Furthermore, variations in brain activity among specific emotions are expected.


[1] A. Shackman and T. Wager, "The emotional brain: Fundamental questions and strategies for future research", Neuroscience Letters, vol. 693, pp. 68-74, 2019. Available: 10.1016/j.neulet.2018.10.012.

[2] M. Westgarth, C. Hogan, D. Neumann and D. Shum, "A systematic review of studies that used NIRS to measure neural activation during emotion processing in healthy individuals", Social Cognitive and Affective Neuroscience, vol. 16, no. 4, pp. 345-369, 2021. Available: 10.1093/scan/nsab017.

[3] M. Balconi, E. Grippa and M. Vanutelli, "What hemodynamic (fNIRS), electrophysiological (EEG) and autonomic integrated measures can tell us about emotional processing", Brain and Cognition, vol. 95, pp. 67-76, 2015. Available: 10.1016/j.bandc.2015.02.001