Aging and natural death: loss of consciousness?
It is well known that old animals and humans tend to be less aware or
conscious (Cheng et al. , 2020). The ability to learn, and form
new memory are significantly reduced. At the synaptic level, it has been
reported that hippocampal late-phase LTP is impaired in old animals that
performed poorly in memory tests. In those animals that show normal
memory performance, late-phase LTP is normal (Bach et al. , 1999).
This finding suggests the importance of synaptic LTP in age-related
memory loss. Recently, it has also been reported that synaptic tagging
in the ACC is reduced in middle-aged animals (Zhou et al. , 2023).
Similarly, synaptic plasticity is less robust in the aged animals’
cortex. It is quite possible that these reduced synaptic LTP and tagging
will contribute to altered consciousness levels in orders. It will be
very important to investigate the last moments of natural death by aging
if the loss of consciousness is due to the failure of synaptic
transmission and plasticity in the brain. Natural death due to aging may
be related to changes in consciousness or shutdown of the consciousness
network. It remains to be explored if deep brain stimulation and/or
novel chemicals that increase synaptic activity/plasticity may prolong
life before natural death.