What can neuroscience tell us about our 'self'?

when does a healthy ego cross the Rosetta stone language
line into unhealthy territory? Where is the line between confident, positive self-image and grandiose self-importance, which might signal a personality disorder or other psychiatric illness? More fundamentally, what do we mean by ego, from a neural perspective? Is there a brain circuit or neurotransmitter system underlying ego that is different in some people, giving them too much or too little?What is Ego?What ego is depends largely on who you ask. Philosophical and psychological definitions abound. Popularly, ego is generally understood as one's sense of self-identity or how we view ourselves. It may encompass self-confidence, self-esteem, pride, and self-worth, and is therefore influenced by many factors, including genes, early upbringing, and stress.The popular concept of ego is a far cry from what Sigmund Freud elaborated at the turn of the 19th century in his seminal work on psychoanalytical theory. Freud distinguished between primary (id) and secondary (ego) cognitive systems and proposed that the id, or unconscious, was characterized by a free exchange of neural energy and more primitive or animistic thinking. It was the job of the ego, the conscious mind, to minimize that free energy, to bind it and thereby regulate the impulses of the unconscious. It was Freud's attempt to link the workings of the unconscious mind to behavior, says Joseph T. Coyle, M.D., chair of psychiatry and neuroscience at Harvard School of Medicine/McLean Hospital and a Dana Alliance for Brain Initiatives member.Ego constructs continue to be used Rosetta Stone German Levev 1-5
in some psychoanalytical therapies, but beyond that, the term seems to be falling out of favor in modern psychiatry. (Ego is so last century, quips Coyle.) Dana Alliance member Jerome Kagan, Ph.D., professor emeritus of psychology at Harvard, says: Ego is a terrible word. In Freudian theory, ego has a meaning-not a very precise one, but a meaning. But you can't take the word ego out of Freudian theory and apply it in non-Freudian ways. It just doesn't work.According to psychiatrist John M. Oldham, M.D., chief of staff at Baylor College of Medicine's Menninger Clinic and President-elect of the American Psychiatric Association (APA), terms like sense of self or self-identity are more common today. The new diagnostic criteria for personality disorders being developed for the revised APA Diagnostic and Statistical Manual of Psychiatric Disorders (DSM-5) will reflect this newer language, he says.Where's the Ego in Neuroscience?If ego is loosely defined in psychiatric circles, a neural definition is virtually nonexistent. Ego doesn't exist in the brain, says Kagan. What does exist, he explains, is a brain circuit that controls the intrusiveness of feelings of self-doubt and anxiety, which can modulate self-confidence. But, Kagan says, We are nowhere near naming the brain circuit that might mediate the feeling of 'God, I feel great; I can conquer the world.' I believe it's possible to do, but no one knows that chemistry or that anatomy.Dana Alliance member Joseph LeDoux, Ph.D., a neurobiologist at New York University, has argued that psychological constructs such as ego are not incompatible with modern neuroscience; scientists just need to come up with better ways of thinking about the self and its relation to the brain. For many people, the brain and the Rosetta Stone Italian Levev 1-5
self are quite different, he writes in The Synaptic Self, where he made the opposite case. For LeDoux, it's a truism that our personality -- who we are in totality -- is represented in the brain as a complex pattern of synaptic connectivity, because synapses underlie everything the brain does. We are our synapses, he says.Researchers are increasingly applying the tools of modern neuroscience to try to understand how the brain represents self and other aspects of ego as popularly defined -- they just don't call it ego. Brain-imaging studies have used self-reference experiments to investigate the neurobiology of self. For example, asking a subject to make a judgment about a statement, such as I am a good friend versus a statement that is self-neutral, such as water is necessary for life. Others have looked at brain pathology in people with disorders of self. These studies have fairly consistently linked self-referential mental activity to the medial prefrontal cortex, a subregion of the frontal lobe where higher-order cognitive functions are processed.The medial prefrontal cortex is the locus of the brain's default mode network, where metabolic activity is highest when the brain is not actively engaged in a task. During task performance, default mode activity decreases. Washington University neuroimaging pioneer and Dana Alliance member Marcus E. Raichle, M.D., first reported the default mode and has argued that default-state activity may hold clues to the neurobiology of self.[i]