The article explores the mechanisms by which anesthetics induce unconsciousness and the conditions under which consciousness may persist despite anesthetic administration. It highlights that while anesthesia typically leads to unresponsiveness and amnesia, the extent of unconsciousness varies. Anesthetics can cause unconsciousness by disrupting the brain's ability to integrate information, particularly in the posterior parietal area, leading to functional disconnection and a loss of information capacity. The thalamus, a key structure involved in consciousness, may serve as a switch or a readout of global cortical activity. Cortical effects of anesthetics are often observed in mesial parietal cortex and lateral temporo-parieto-occipital regions, which are crucial for maintaining consciousness. The loss of consciousness is associated with a breakdown of cortical connectivity and integration, or a reduction in the repertoire of discriminable states, as measured by integrated information (phi). The article also discusses the implications of these findings for developing more specific anesthetic agents and improving consciousness monitoring during surgery.The article explores the mechanisms by which anesthetics induce unconsciousness and the conditions under which consciousness may persist despite anesthetic administration. It highlights that while anesthesia typically leads to unresponsiveness and amnesia, the extent of unconsciousness varies. Anesthetics can cause unconsciousness by disrupting the brain's ability to integrate information, particularly in the posterior parietal area, leading to functional disconnection and a loss of information capacity. The thalamus, a key structure involved in consciousness, may serve as a switch or a readout of global cortical activity. Cortical effects of anesthetics are often observed in mesial parietal cortex and lateral temporo-parieto-occipital regions, which are crucial for maintaining consciousness. The loss of consciousness is associated with a breakdown of cortical connectivity and integration, or a reduction in the repertoire of discriminable states, as measured by integrated information (phi). The article also discusses the implications of these findings for developing more specific anesthetic agents and improving consciousness monitoring during surgery.