The role of alpha oscillations in attentional prioritization of emotional arousal

• Applicant: Dr. Valeria Bekhtereva
• Subject Area: Biological Psychology and Cognitive Neuroscience ; Human Cognitive and Systems Neuroscience
• Term: from 2020 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 442650349

Emotionally arousing images are often regarded as a privileged stimulus category, whose visual processing is prioritized due to their pivotal role in motivation and behavior. However, it is not yet clear how prioritized encoding of and attentional bias towards emotionally arousing content is implemented in the human brain. Although studies with steady-state visual evoked potentials (SSVEPs) have been used to examine how such stimuli capture attention, the role of ongoing, endogenously generated brain activity, such as alpha oscillations, has been relatively neglected. There is strong evidence that alpha oscillations generated in visual cortex are involved in gating attention at the neural level, and thus represent a key attentional mechanism. For example, lateralized changes in alpha band activity are consistently found in spatial attention studies, with attenuated occipital alpha band power over the hemisphere contralateral to the attended location and enhanced alpha ipsilateral to the attended location. Thus, alpha oscillations may have a role in prioritization of emotional stimuli. Changes in perceptual processing of visual images due to their emotional salience or task relevance may be reflected by attenuation of alpha oscillations, which in turn reflects cortical engagement and gating the access of relevant sensory input to higher-order processing areas. However, no study to date has obtained direct electrocortical evidence on whether changes in alpha may (causally) affect the sensory representations of pictures as a function of emotional arousal or attention, because none of previous research has simultaneously assessed continuous perceptual processing and alpha rhythm changes during EEG. In the proposed project, we aim to obtain detailed evidence on the continuous dynamic interplay between alpha band modulations and sensory (visual) processing with images varying in emotional content. The experiments will elucidate whether alpha band activity covaries with emotional arousal as measured via subjective reports of image arousal, or rather is modulated by top-down selective attention, and whether the mechanisms indexed by alpha interact with those tracked by SSVEPs. The project will ultimately provide new insights and evidence into whether alpha and SSVEP modulations with emotional arousal may index similar or complementary cortical mechanisms in gating attention, and whether both may similarly be modulated by top-down higher-order cortical areas involved in emotional encoding.

• DFG Programme: Research Fellowships
• International Connection: United Kingdom
• Host: Dr. Matt Craddock