Spatiotemporal dynamics of multispectral oscillatory activity underlying the processing of negative and positive emotional images.

Behavioral and neural responses to visual scenes depicting potential threat or harm constitute core aspects of human behavior and can illuminate symptoms of internalizing disorders. Decades of research have shown that negative content undergoes facilitated processing across a distributed brain network whereby perception is facilitated, and cognitive systems appraise the stimulus to regulate emotions and plan motor action. However, relatively limited studies have examined the multispectral dynamics underlying the neural processing of negative emotional images, with mixed results among existing studies. Herein, we used magnetoencephalography (MEG) to derive dynamic functional maps of positive and negative image processing in healthy adults. Alpha (from 200 to 700 ms) and beta (from 200 to 550 ms) oscillations were stronger for negative images in primary and ventral visual regions, as well as parietal and prefrontal cortices (all ps < .005). Similarly, theta activation was stronger for negative images in ventral temporal cortex (p < .001) from 0 to 250 ms. Lastly, gamma oscillatory activity was stronger for negative images in the pre-supplementary motor area (p < .005) from 150 to 500 ms. These results are consistent with the literature in regard to the critical brain regions involved in emotional processing, but importantly also delineate the multispectral oscillatory dynamics within these regions that support the swift synthesis of low-level visual inputs, appraise emotional meaning, and guide appropriate motor system activation (as necessary) to avoid harm.