Figure 6.

Ignition in a large-scale cortex. (a) Signal propagation across some areas but not others in response to a brief input to V1 in a large-scale monkey cortex model of spiking neurons. The areas along the ventral stream showing strong response activity are indicated in orange. The list of full names of cortical areas shown is provided in Markov et al. (2014a). (b) The peak response averaged over areas in the occipital, temporal, parietal, and frontal lobes as a function of the intensity of a stimulus to V1. (c) Illustration of ignition as a physiological signature of consciousness. (d) Average normalized activity of neurons in V1, V4, and dorsolateral prefrontal cortex (DLPFC) of monkeys performing a visual detection task with intermediate contrast levels around the detection threshold. Neural signals in visual areas predominantly reflect the physical stimulus in hit and miss trials, whereas neural firing in the DLPFC displays strong responses correlated with subjective awareness in hit and false alarm trials. Panels a and b adapted from Joglekar et al. (2018). Panel c adapted with permission from Dehaene et al. (2006). Panel d adapted with permission from van Vugt et al. (2018).