Are low spatial frequencies or high contrasts the trigger of threat detection?

International audienceResearch in visual cognition has proposed that low spatial frequency (LSF) information could rapidly provide a coarse visual cue for basic emotional response to a potential visual threat in the environment. This effect would be mediated by a large cerebral network involving fronto-parietal and temporal cortical areas, but also subcortical tecto-pulvinar regions. We report a series of behavioral, connectionist and neuroimaging studies in which we investigated the differential role of spatial frequency channels in response to visual danger and emotional facial expressions. Results show a better recognition of visual danger for LSF compared to HSF band-pass stimuli in human subjects but also artificial neural networks. However, our recent neuropsychological data (on Parkinson’s disease and Tourette patients) but also magnetoencephalographic data suggest that contrast, more than spatial frequencies, plays a key role in triggering amygdala’s response through a subcortical pathway. This suggests that the specific role of LSF information for fast recognition of a potential danger in the visual environment could actually be related to their high contrast inherent to the low spatial frequencies