RT Journal Article
SR Electronic
T1 A Bidirectional Link between Brain Oscillations and Geometric Patterns
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 7921
OP 7926
DO 10.1523/JNEUROSCI.0390-15.2015
VO 35
IS 20
A1 Federica Mauro
A1 Antonino Raffone
A1 Rufin VanRullen
YR 2015
UL http://www.jneurosci.org/content/35/20/7921.abstract
AB Like hallucinogenic drugs, full-field flickering visual stimulation produces regular, geometric hallucinations such as radial or spiral patterns. Computational and theoretical models have revealed that the geometry of these hallucinations can be related to functional neuro-anatomy. However, while experimental evidence links both visual flicker and hallucinogenic drugs to upward and downward modulations of brain oscillatory activity, the exact relation between brain oscillations and geometric hallucinations remains a mystery. Here we demonstrate that, in human observers, this link is bidirectional. The same flicker frequencies that preferentially induced radial (<10 Hz) or spiral (10–20 Hz) hallucinations in a behavioral experiment involving full-field uniform flicker without any actual shape displayed, also showed selective oscillatory EEG enhancement when observers viewed a genuine static image of a radial or spiral pattern without any flicker. This bidirectional property constrains the possible neuronal events at the origin of visual hallucinations, and further suggests that brain oscillations, which are strictly temporal in nature, could nonetheless act as preferential channels for spatial information.