TY - JOUR TI - Perception is associated with the brain’s metabolic response to sensory stimulation AU - DiNuzzo, Mauro AU - Mangia, Silvia AU - Moraschi, Marta AU - Mascali, Daniele AU - Hagberg, Gisela E AU - Giove, Federico A2 - Kok, Peter A2 - Moore, Tirin A2 - Kok, Peter A2 - Norris, David A2 - Frangou, Polytimi VL - 11 PY - 2022 DA - 2022/02/28 SP - e71016 C1 - eLife 2022;11:e71016 DO - 10.7554/eLife.71016 UR - https://doi.org/10.7554/eLife.71016 AB - Processing of incoming sensory stimulation triggers an increase of cerebral perfusion and blood oxygenation (neurovascular response) as well as an alteration of the metabolic neurochemical profile (neurometabolic response). Here, we show in human primary visual cortex (V1) that perceived and unperceived isoluminant chromatic flickering stimuli designed to have similar neurovascular responses as measured by blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) have markedly different neurometabolic responses as measured by proton functional magnetic resonance spectroscopy (1H-fMRS). In particular, a significant regional buildup of lactate, an index of aerobic glycolysis, and glutamate, an index of malate–aspartate shuttle, occurred in V1 only when the flickering was perceived, without any relation with other behavioral or physiological variables. Whereas the BOLD-fMRI signal in V1, a proxy for input to V1, was insensitive to flickering perception by design, the BOLD-fMRI signal in secondary visual areas was larger during perceived than unperceived flickering, indicating increased output from V1. These results demonstrate that the upregulation of energy metabolism induced by visual stimulation depends on the type of information processing taking place in V1, and that 1H-fMRS provides unique information about local input/output balance that is not measured by BOLD-fMRI. KW - central visual system KW - visual perception KW - human brain metabolism KW - lactate KW - BOLD-fMRI KW - single-voxel 1H-fMRS JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -