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The Light Before the Dark: When the Mind Returns- terminal lucidity · Understanding the Brain

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  Speaker 1: Welcome back everybody. Our podcast is back. Sorry for the break.
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  Speaker 1: Today we're going to be talking about a phenomena that
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  Speaker 1: challenges our standard neurobiological understanding of neurodegeneration. It's a concept
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  Speaker 1: called terminal lucidity. In patients with advanced Alzebers or severe TBI,
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  Speaker 1: we typically see a progressive, one way degradation of the
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  Speaker 1: critical and hippocampal circuits. The physical architecture of the brain,
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  Speaker 1: the neurons, of the synaptic connections is objectively dissolving. Yet
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  Speaker 1: we see these well documented cases. We're twenty four to
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  Speaker 1: forty eight hours before death, the lights suddenly turn on.
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  Speaker 1: These individuals who may not have recognized their own children
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  Speaker 1: for a decade, suddenly regain full access to their autobiographical memory,
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  Speaker 1: linguistic fluency, and even their personality. From a mechanistic perspective,
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  Speaker 1: this is highly nonintuitive. If the hardware is degraded, how
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  Speaker 1: can the software run at one hundred percent efficiency? Well,
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  Speaker 1: there are some working hypothesis. What involves the last gas
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  Speaker 1: chemical surge as the body begins the system systemic shutdown process.
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  Speaker 1: There may be a massive release of neuromodulators that briefly
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  Speaker 1: bypass damaged signaling pathways. It's essentially a forced overclocking of
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  Speaker 1: the remaining neural tissue. Another possibility is it involves the
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  Speaker 1: reorganization of neural networks. As possible that the brain under
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  Speaker 1: extreme physiological stress shifts from its traditional hierarchical processing to
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  Speaker 1: a highly integrated global state. Well, we don't have definite
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  Speaker 1: proof to induce this, and frankly it may be a
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  Speaker 1: unique biological signal of the transition toward death. It does
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  Speaker 1: suggest that the self or the mind is far more
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  Speaker 1: resilient than the physical atrophy of the brain might suggest.
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  Speaker 1: It forces us to ask is a memory actually gone
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  Speaker 1: or is it simply a signaling problem if the body
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  Speaker 1: could briefly override when the end is near. The data
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  Speaker 1: is sparse, but the implications for neuroscience are profound.