Our memories and our consciousness are the direct result of the relationships among neurons in our brain. These neurons form unique structures called neural networks which allow us to do things like imagine the future or remember an event without being prompted by a stimulus in our present environment. Most mammals with simpler brains (cats, for example) generally have to be prompted with an environmental stimulus (an alarm clock, a can being opened) before they can remember the relationship between the stimulus and themselves. Human neural networks are sophisticated enough that we can form these memories in isolation, no matter how far removed we are from the stimuli that originally helped form them. How do these neural networks result in human consciousness and what do they ultimately mean for the course of modern neuroscience? What can we hope to learn by studying the relationships among neurons in our brains?
First, we must establish there are grades of consciousness: a person is not fully conscious the second he or she wakes. Patients with brain injuries (lack of oxygen, physical trauma) have experienced degrees of consciousness as well. There is a critical point at which the brain’s neural networks and chemistry present the ideal conditions for human consciousness to “re-occur.” There have been many theories put forth as to how consciousness originally emerged, including tracking the amount of surface oxygen available at various periods in pre-history: without enough oxygen, consciousness in the form we recognize today would have been impossible.
Neuroscientist Christof Koch of the Allen Institute for Brain Science breaks down human consciousness thusly: “…consciousness arises within any sufficiently complex information-processing system.” What this means for modern neuroscience is that consciousness is directly related to a) how many neurons a particular organism has and b) how those neurons are arranged into neural networks. Medical researchers hope to better understand how conscious thought emerges from such processes by working in the US Human Brain Initiative as well as Europe’s Human Brain Project, two far-reaching, well-funded programs that have been designed to help us discover the physiological mechanisms behind human consciousness.
What implications could such an understanding have for modern neuroscience and the general public? First, if medical researchers understand human consciousness on a cellular level, this greatly enhances our ability to understand conditions that affect consciousness (Alzheimer’s disease, for example). The more we know about the ways our brains form thoughts, memories, and patterns, the better we can understand how our brains affect our bodies, including the electrical signals the brain sends in order to complete a multitude of daily tasks. This could lead to a better understanding of nerve trauma, neural cell regeneration, and physical rehabilitation for those with spinal cord injuries or other serious illnesses. As the Human Brain Project and the BRAIN Initiative advance, researchers will hopefully uncover more knowledge regarding the brain and how it functions.