Nicole Naue, Daniel Strüber, Ingo Fründ, Jeanette Schadow, Daniel Lenz, Stefan Rach, Ursula Körner, Christoph Herrmann, "Pattern reversal elicits stronger evoked and induced gamma-band responses than motion", NeuroImage, vol. 55, no. 2, pp. 808-817, 2010.

Hitherto, it is unclear whether gamma-band responses (GBRs, ≈40 Hz) of the electroencephalogram are more strongly modulated by visual stimulation with moving or rather with static objects. Most results suggest that GBRs occur more consistently in response to motion. We measured the electroencephalogram of healthy subjects watching high contrast, achromatic gratings. Briefly after their onset, the gratings either started to move or reversed their black and white pattern. The evoked and induced GBRs were analyzed in response to the onset of the grating, the pattern reversal, and the motion onset. We investigated how these three experimental conditions modulate the GBR and whether such modulations could be explained by microsaccades of the eyes or are due to neuronal processes in visual cortex. Induced as well as evoked GBRs were stronger for pattern reversal than for motion onset. There was no significant difference between the onset of the grating and motion onset. The rate of microsaccades showed a different pattern of results across conditions with a time course different from that of induced GBRs. Therefore, we argue that the induced GBRs in our experiment reflect neuronal processes in visual cortex.