Neurobiological Architecture of Early Alzheimer 's Failure: A Structural and Biochemical Perspective

Alzheimer's disease is manifested by a pattern of asymmetric neurofunctional decline, with initial impairment in the consolidation of recent memories and relative preservation of remote information. This dissociation is related to the topography of synaptic degeneration and the biochemical selectivity of structures such as the hippocampus, entorhinal cortex, anterior cingulate cortex and dorsolateral prefrontal cortex. The reduction in the synthesis and transmission of neurotransmitters, especially acetylcholine and dopamine, is associated with loss of efficiency in episodic memory, executive functions and sustained attention. The loss of functional connectivity, measured by diffusion and functional imaging, shows that Alzheimer's failure is not only morphological, but also functional. Understanding this complex dynamic is fundamental for the development of preventive approaches and early interventions based on applied neuroscience.