Mermaid, neuroscience does not deal with "Temporalities of Identity"-
Yes, it does. Look at work by Dennett, and especially work by Damasio. Nothing to do with MLC, but all about the neurology of identity.
Here's a summary Damasio's neurological research on temporalities of identity.
Damasio hypothesised three neurological levels of the self, which explains how we can remain the same, yet change with time and context. The first level is the stable, but unconscious, proto-self, present before birth (1999:154); the second level, core-consciousness (1999:16), leads to a sense of self in the present moment, and is the source of emotions (1999:219) and is stable across a life time, under strong gene control. The third level, extended consciousness, associated with autobiographical, narrative self (self-identity), is an awareness of the lived past and anticipated future, language and memories playing a key role. It developed later evolutionarily than core and proto-self, and is dependent on core consciousness for its existence. Thus thought and learning are not limited to language, nor does language give access to the whole of consciousness. Although there is a tendency towards multiple stories about the self, the deeply biological self selects drafts according to a unified sense of self. There are limits to how this unity can be maintained in all contexts at all times, and there are instances when conflicting conscious and unconscious desires may change the direction of this self. Damasio argues that there is a tendency to “return to base”.
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This bit is about the neurology of decision making. None of us makes purely rational decisions; neurologically, emotions always underlie them.
Recent neurological research supports the idea that emotions underlie rationality and decision-making. Wilson (2004) shows how the “adaptive unconscious” filters information, sets goals, and makes judgements and decisions. These processes may lead to both thoughts and actions, so conscious thoughts may be only rationalizations of unconscious processes. Damasio (1994, 1999, 2003) demonstrates that patients whose emotional reactivity is impaired (through damage to the prefrontal cortex or the anterior cingulated cortex) have immense difficulty making decisions. This difficulty exists despite patients having full knowledge of decision outcomes and normal intelligence. Their difficulty arose from their inability to assign values to the options available, leading Damasio to propose the Somatic Marker Hypothesis. This describes how the brain is positively or negatively affected by experiences from socialization, connecting rationality, emotions and the self. Knowledge, says Damasio, is thus deeply dispositional. However, this is not a behaviourist mechanism; somatic markers do not cause decisions, but form the neurological basis of a personal value system. According to Damasio (1994), emotions have precedence neurologically over rationality. As not every aspect of behaviour is conscious, not everything is open to rationality. Paradoxically, this means that rational decisions can be made subconsciously, using a value system formed according to emotional reactions.
This has important consequences, as rational decisions do not only arise from abstract knowledge, but are linked to emotional biases. These lie partly in the unconscious domain; thus tacit knowledge is important. It supports the idea of a pragmatic, bounded rationality in which relationships and trust are important. Thus socially rational behaviour is not necessarily conscious, and conscious knowledge does not necessarily lead to rational behaviour. Neither knowledge nor emotions lead to socially rational decisions on their own, but emotions, as markers of social values, are an essential part of decision-making. Yet explanations of decision-making may only be an illusion, a rationalization after decisions have been made unconsciously (Wilson 2004).
I know this is a bit academic and dense in constructs, but I hope it helps.
My point is that ideas such as self and identity are always social constructions; the third level of self, which is autobiographical, is linguistic, and comes from how we develop and change in social context. We all have multiple drafts of this "self" which are always changing. There is no one true "self", but proto-self is closest to it, although it's not accessible to our consciousness except in brief glimpses. The second level, emotional self, together with somatic marker mechanisms (from by social learning) may affect how our MLCers appear to suddenly redraft their social identity, especially if conflicting emotions bubble up from the unconscious.
It's unlikely that neurological disorders cause MLC, which basically a social and emotional crisis. I've posted these summaries to show how neurologically people reorganise their identities, life stories, and make decisions.
It's entirely possible of course that some people have a neurological malfunction, from an ischemic attack or other causes, but it's unlikely to be an explanation for what we call MLC. Most especially, some of the diseases mentioned on this forum have a number of other manifestations.
It is possible that hormonal changes underlie the effects seen in some MLCers.
In other cases, it seems more likely that psychological and social forces are at play.
Hope this helps, to anyone who has read through to the end.
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