Neuroscientific and neurophilosophical investigation of the link between self and brain

One of the most fascinating characteristics of human nature is our ability to experience ourself as a self and person. However, because we have no direct access to our brain in experience, the nature of the link between brain and self, and thus between mental and neural states, is not self-evident. Recent imaging studies suggest that cortical midline structures (CMS) may be involved in the neural processing of self.

Our work focuses on the relationship between CMS, emotional processing, and self-related processing in both healthy and psychiatric subjects using a variety of neuroimaging techniques. Our work branches into the development of psychiatric diagnostic and therapeutic tools, such as for depression and schizophrenia. In addition, our work both uses and in turn has novel implications for philosophical avenues of investigation spanning the mind-brain relation, personal identity, and our brain-based knowledge apparatus.

Neuroscientific approach: We make use of a variety of imaging techniques including fMRI, PET, DTI, EEG, MEG, and TMS. These investigations are combined with neurochemical studies focusing on the measurement of metabolites (such as GABA and glutamate) using MRS as well as neurochemical challenge with GABAergic or glutamatergic substances.

Neuropsychiatric approach: We investigate CMS/emotional/self-related neural mechanisms in patients suffering from emotional disorders such as depression or anxiety, as well as those with alterations in experience of self. Such investigations help to reveal the causes of these conditions, the knowledge of which is vital to the production of new treatments. In addition, an understanding of mechanisms underlying changes in experience of self is an important component in the understanding of the link between the mind, self, and brain.

Neurophilosophical approach: Our empirical studies require an epistemic, ontological, and ethical reconsideration of the link between the self and the brain. Consequently, they also have implications for old philosophical problems such as the mind-brain relationship and “the self”. Most importantly, we aim to develop empirically plausible definitions of mental states (for example, qualia), the self, and the mind-brain relationship. In addition, new developments in neuroscience and psychiatry that enable us to manipulate our mental states and even personal identity call for clarification of the concepts involved and discussion of corresponding ethical issues.

Vision for the Future
Our vision is to reveal the key neural mechanisms that underlie the generation of mental states and the self. Insight into the physiology of CMS gained through both neuroimaging and conceptual work may elucidate specific functional principles underlying this link. Application of this approach to both healthy and psychiatric subjects and augmentation with translational work opens the door to the development of reliable diagnostic markers and novel therapeutic interventions. Insight into the link between neural and mental states bears profound implications for understanding human nature, which feeds back into the ongoing development of neuroepistemology and neuroethics.