Biology subjects

de Gelder, B.

Publications and source records attributed to de Gelder, B..

3 recordsLinked to original sources

bioRxiv2018

Layer-specific ultra-high field 7T fMRI showing that threat anticipation is mediated by the pulvinar input to the superficial layers of primary visual cortex (V1)

The perceptual system gives priority to threat-relevant signals with survival value. Its mechanism may not only include the processing initiated in the presence of threat signals but also in the mere anticipation of such signals. Here, we show that the pulvinar modulates activity in the early visual cortex (V1) specifically in threat anticipation. Using ultra-high-field 7T fMRI, we examined the layer-specific interaction between V1 and the pulvinar, while taking advantage of the fact that the directionality of such interaction is anatomically constrained in specific V1 layers. Only in anticipation of a fearful face target, but not of a control happy face target, was false perception of anticipated-yet-unpresented target face accompanied by stronger activity in the V1 superficial-cortical-depth (layers 1-3), which was preceded by pre-target-onset pulvinar activity. The pulvinar may contribute to the visual processing initiated in the anticipation of threat, and play an important role in anxiety.

neuroscience↗

bioRxiv2018

First person experience of threat modulates cortical network encoding human peripersonal space

Peripersonal space is the area directly surrounding the body, which supports object manipulation and social interaction, but is also critical for threat detection. In the monkey, ventral premotor and intraparietal cortex support initiation of defensive behavior. However, the brain network that underlies threat detection in human peripersonal space still awaits investigation. We combined fMRI measurements with a preceding virtual reality training from either first or third person perspective to manipulate whether approaching human threat was perceived as directed to oneself or another. We found that first person perspective increased body ownership and identification with the virtual victim. When threat was perceived as directed towards oneself, synchronization of brain activity in the human peripersonal brain network was enhanced and connectivity increased from premotor and intraparietal cortex towards superior parietal lobe. When this threat was nearby, synchronization also occurred in emotion-processing regions. Priming with third person perspective reduced synchronization of brain activity in the peripersonal space network and increased top-down modulation of visual areas. In conclusion, our results showed that after first person perspective training peripersonal space is remapped to the virtual victim, thereby causing the fronto-parietal network to predict intrusive actions towards the body and emotion-processing regions to signal nearby threat.

neuroscience↗

bioRxiv2017

Gender-specific brain activation during visual art perception

The human body is the most common object of pictorial representation in western art. The goal of this study was to probe its evolutionary basis of visual art perception by investigating neural markers of gender-specific brain activity triggered by paintings of male and female images. Our results show significant activity in brain areas other than those recently associated with visual arts perception. Novel findings concern participant-general as well as gender specific brain activity. Although our participants were fully aware that they were viewing artworks, the inferior parietal lobule - known for its role in the perception of emotional body images - and the somatosensory cortex - which is related to touch - were selectively active for female body paintings in all participants. The most interesting finding as regards gender was that the sight of female bodies activates the subgenual anterior cingulate cortex in males, an area known to subserve autonomic arousal. In contrast, in females the sight of the male body activated reward and control related parts of the dorsal anterior cingulate cortex. This supports the notion that basic evolutionary processes operate when we view body images, also when they are paintings far removed from daily experience.

neuroscience↗