Human consciousness is a complex phenomenon that generally refer to the state of being aware of and responsive to one's surroundings. Consciousness encompasses a wide range of mental phenomena, including thoughts, feelings, perceptions, and memories.
One of the key features of human consciousness is its subjectivity. Each individual's experience of consciousness is unique and private. We cannot directly experience the consciousness of others. This makes it difficult to study consciousness scientifically, as we are limited to our own subjective experiences.
Another important feature of human consciousness is the qualitative experiences of consciousness, such as the redness of red, the pain of a toothache, or the smell of coffee. They are difficult to define or explain. It is one of the main challenges for the scientists to study consciousness.
Despite the challenges, there has been significant progress in our understanding of consciousness in recent years. Scientists have identified a number of brain activities that are associated with conscious experience but still do not fully understand how these brain activities give rise to consciousness.
Here are some of the different theories of consciousness:
- Integrated information theory (IIT) Proposed by neuroscientist Giulio Tononi in 2004. IIT proposes that consciousness is a fundamental property of any system that has a high degree of information integration. This means that the system's parts are highly interconnected and that the system as a whole is more than the sum of its parts. IIT provides a way to measure the degree of consciousness of a system. It is based on the idea that consciousness is a measure of how much information a system can process in a unified way. The more integrated a system is, the more conscious it is. IIT measures the degree of information integration in a system using a mathematical quantity called φ (phi). IIT is a unifying theory of consciousness and has been used to explain a wide range of phenomena related to consciousness, including the subjective experience of qualia, the difference between conscious and unconscious states, and the emergence of consciousness in artificial systems. IIT is a complex and challenging theory, but it is one of the most promising theories of consciousness that has been proposed. IIT has been criticized for being difficult to test and for not providing a clear explanation of how consciousness arises from physical matter.
- Higher-order thought theory (HOT) Proposed by philosophers David Chalmers and Daniel Dennett in the 1980s. HOT proposes that consciousness is the ability to have thoughts about one's own thoughts and is a special kind of mental state that is reflexive. HOT is a qualitative theory of consciousness and it is concerned with the subjective experience of consciousness, rather than with the neural correlates of consciousness. HOT is a representational theory of consciousness and it proposes that consciousness is a representation of mental states. HOT is a reflexive theory of consciousness and it proposes that consciousness is the ability to have thoughts about one's own thoughts. HOT is a complex and challenging theory and it is one of the most promising theories of consciousness that has been proposed. But it does not provide a clear explanation of how higher-order thoughts arise from physical matter. Also it does not provide any methods to measure the presence or absence of higher-order thoughts.
- Global workspace theory (GWT) Proposed by cognitive scientists Bernard Baars and Stan Franklin in the late 1980s. GWT proposes that consciousness is a global workspace in the brain that allows different brain regions to communicate with each other. This workspace allows us to focus on one thing at a time and to be aware of our thoughts, feelings, and perceptions. GWT is a functional theory of consciousness and it focuses on the function of consciousness, rather than on its underlying mechanisms. GWT is a cognitive architecture theory of consciousness and it proposes that consciousness is a property of a specific cognitive architecture. GWT is a communication-based theory of consciousness and it proposes that consciousness arises from the communication between different brain regions. GWT has been used to explain a wide range of phenomena related to consciousness, including the subjective experience of qualia, the difference between conscious and unconscious states, and the emergence of consciousness in artificial systems.