Feedback to distal dendrites links fMRI signals to neural receptive fields in a spiking network model of the visual cortex.
The blood oxygenation level-dependent (BOLD) response has been strongly associated with neuronal activity in the brain. However, some neuronal tuning properties are consistently different from the BOLD response. We studied the spatial extent of neural and hemodynamic responses in the primary visual cortex, where the BOLD responses spread and interact over much longer distances than the small receptive fields of individual neurons would predict. Our model shows that a feedforward-feedback loop between V1 and a higher visual area can account for the observed spread of the BOLD response. In particular, anisotropic landing of inputs to compartmental neurons were necessary to account for the BOLD signal spread, while retaining realistic spiking responses. Our work shows that simple dendrites can separate tuning at the synapses and at the action potential output, thus bridging the BOLD signal to the neural receptive fields with high fidelity.
Department of Neuroscience and Biomedical Engineering, School of Science, Aalto University, Espoo, Finland; Aalto Neuroimaging, Aalto University School of Science, Espoo, Finland; hanna.m.heikkinen@iki.fi.
Hanna
H
Heikkinen
Department of Neuroscience and Biomedical Engineering, School of Science, Aalto University, Espoo, Finland; Aalto Neuroimaging, Aalto University School of Science, Espoo, Finland; Clinical Neurosciences, Neurology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Fariba
F
Sharifian
Department of Computer Science, Aalto University School of Science, Espoo, Finland; and.
Ricardo
R
Vigario
Aalto Neuroimaging, Aalto University School of Science, Espoo, Finland; Clinical Neurosciences, Neurology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Simo
S
Vanni
D000200:Action Potentials / Q000502:physiology; D000328:Adult; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003712:Dendrites / Q000502:physiology*; D025461:Feedback, Physiological / Q000502:physiology*; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D016571:Neural Networks, Computer; D009474:Neurons / Q000502:physiology; D010100:Oxygen / Q000097:blood*; D014793:Visual Cortex / Q000098:blood supply / Q000502:physiology*
D010100:Oxygen
BOLD; BOLD simulation; Brian simulator; V1; conductance-based model; dendritic processing; fMRI; hemodynamic coupling; recurrent neural network; visual cortex