Scientists could be one step closer to understanding where consciousness resides in the brain. A new study, led by researcher Jun Kitazono from the Department of General Systems Studies at the University of Tokyo, shows the importance of certain types of neural connections in identifying consciousness.
“Where consciousness resides in the brain has been one of the most important questions in science. Although we have not arrived at a conclusive answer, much empirical evidence has been accumulated in the course of searching for the minimal mechanisms sufficient for conscious experience.” , or the neural correlates of consciousness”, explains Masafumi Oizumi , co-author of the research published in the journal Cerebral Cortex.
The object of the study was to identify the areas of the brain where consciousness resides. To do this, the researchers looked for a specific hallmark of consciousness within the brain’s neural networks, the bidirectional pathways. That is, when we see something or experience a sensation, our brain receives information, but receiving these signals is not enough for consciousness. Our brains also need to give information back, in what is called feedback . But not all parts of the brain can receive both feedback and feedback information.
Hypothesis
The researchers hypothesized that these bidirectional connections are an essential hallmark of the parts of the brain responsible for consciousness.
“Feedback processing alone is insufficient for subjects to consciously perceive stimuli; rather, feedback is also necessary, indicating the need for bidirectional processing. The feedback component disappears not only during the loss of specific contents of consciousness in waking states, but also during unconscious states where conscious experiences are generally lost, such as general anesthesia, sleep, and vegetative states,” he said. Kitazono.
Where is the conscience?
For the experiment, they used a map of the connections between neurons in the brain (also known as a connectome ) as well as computer techniques to test their hypothesis. By applying the algorithm to the map of mouse brain connections, “we found that the extracted complexes with the highest bidirectionality were not evenly distributed among all major regions, but were concentrated in cortical and thalamic regions ,” the authors explain. . “On the other hand, the regions in the other major regions have low bidirectionality. In particular, the cerebellar regions have much lower bidirectionality.”
This discovery points in the same direction that researchers have believed, for decades, that consciousness resides within our brains . The cerebral cortex contains areas essential for the experience of consciousness. Also the thalamus. Be that as it may, these results support the idea that bidirectionality in the brain network is key to identifying the locus of consciousness. We haven’t found out where he is, but it looks like we’re on the right track.
The team is currently analyzing activity-based brain networks in various types of neural recordings. “The ultimate goal of our lab is to find the mathematical relationship between consciousness and the brain . In this study, we have tried to relate the network properties of the brain to the locus of consciousness. We will continue to investigate the relationship between consciousness and the brain.” , towards what our ultimate goal is”, conclude the experts.
Referencia: “Bidirectionally connected cores in a mouse connectome: towards extracting the brain subnetworks essential for consciousness” by Jun Kitazono, Yuma Aoki and Masafumi Oizumi, 21 July 2022, Cerebral Cortex.
DOI: 10.1093/cercor/bhac143
