The human self

My research on self-referential processing in the brain, primarily using electroencephalography (EEG) and magnetoencephalography (MEG), contributes to a "multiple aspect theory of the self."1 My work challenges the idea of a singular, monolithic "self" in the brain, suggesting instead that the human self is dynamic and comprises at least two distinct, serially processed aspects.

Here's a summary of my key findings and propositions:

1. Two Serial Aspects of the Self (Me1 and Me2):

• Early Processing (Me1 - "Non-personal" or "We" Self): At an early cortical processing stage (around 200 ms post-stimulus onset), we found that the brain differentiates between stimuli that have any personal reference (e.g., "my garden," "his garden") and those that have no personal reference (e.g., "a garden"). Crucially, at this early stage, self-related stimuli ("my") are processed similarly to other-related stimuli ("his"). This early effect, referred to as "Me1," is hypothesized to represent a more primitive, "non-personal" self or a sense of "we" – a general engagement with personally relevant information, but not yet distinguishing between "me" and "you." This early processing is observed in left occipito-parietal regions.
• Later Processing (Me2 - "Personal" or "Distinct" Self): At a later processing stage (around 400 ms post-stimulus onset), brain activity patterns elicited by self-related stimuli ("my garden") significantly diverge from both other-related stimuli ("his garden") and non-personal stimuli ("a garden"). This later effect, termed "Me2," is thought to represent the "proper self" – the distinct and differentiated self that is unique from others. This later processing occurs over left fronto-temporal areas.

2. Dynamic and Hierarchical Processing:

• This research emphasizes that self-referential processing is not a single, instantaneous event, but a dynamic and hierarchical process. The brain first processes information as generally relevant to a "self" or "us" (Me1) before refining that processing to distinguish one's own self from others (Me2). This aligns with very early philosophical ideas about separate self-aspects, such as William James's distinction between the "Me" (the empirical self, what is known about oneself) and the "I" (the pure ego, the knower).

In essence, my work tells us that the human self is not a simple, fixed entity but a complex, dynamically constructed phenomenon in the brain, processed in a hierarchical fashion from a more general, "non-personal" engagement to a highly individualized and distinct sense of self over time.