Mind Brain & mind 

In animals, the brain, or encephalon , is the control center of the central nervous body system, responsible for thought. In most animals, the brain is located in the head, protected by the skull & close to the primary sensory apparatus of vision, hearing, equilibrioception, taste & olfaction. While all vertebrates have a brain, most invertebrates have either a centralized brain or collections of individual ganglia. Primitive animals such as sponges do not have a brain at all. Brains could be extremely complex. For example, the human brain contains more than 100 billion neurons, each linked to as many as 10,000 others.

Understanding the relationship between the brain & the mind — mind-body problem is 1 of the central issues in the history of philosophy — is a challenging problem both philosophically & scientifically. There are 3 major philosophical schools of thought concerning the answer - dualism, materialism, & idealism. Dualism holds that the mind exists independently of the brain materialism holds that mental phenomena are identical to neuronal phenomena & idealism holds that only mental phenomena exist.

The most straightforward scientific evidence that there is a strong relationship between the physical brain matter & the mind is the impact physical alterations to the brain have on the mind, such as with traumatic brain injury & psychoactive drug use.

In addition to the philosophical questions, the relationship between mind & brain involves a number of scientific questions, including understanding the relationship between mental activity & brain activity, the exact mechanisms by which drugs influence cognition, & the neural correlates of consciousness.

Through most of history many philosophers found it inconceivable that cognition could be implemented by a physical substance such as brain tissue . Philosophers such as Patricia Churchland posit that the drug-mind interaction is indicative of an intimate connection between the brain & the mind, not that the 2 are the same entity. Descartes, who thought extensively about mind-brain relationships, found it possible to explain reflexes & other simple behaviors in mechanistic terms, although he did not believe that complex thought, & language in particular, could be explained by reference to the physical brain alone.