[Neuropathologic, immunologic and psychobiological aspects of Alzheimer's dementia]

This review attempts a consolidated overview of the results of molecular biological research on amyloid pathology in Alzheimer's disease crosslinked with other aspects of the disease that have not been so much in focus in recent years. The spotlight will be on many pointers to an immunological process as part of the Alzheimer pathology. The problem of the specificity of plaques and of neurofibrillary tangles that both are considered to be classical neuropathological markers of Alzheimer's disease is critically reviewed on the basis of existing findings in neuropathology in non-demented and demented elderly persons. The traditional unidirectional concept that interprets the neuropsychological functions inhibited in Alzheimer's dementia merely as sequels to damaged morphological structures, is questioned. Earlier and more recent experimental findings indicating that dysfunctional and deficient use of neuropsychological functions can inhibit neuronal plasticity and can be the origin of morphological changes, are placed in relation to numerous pointers to non-cognitive mental anomalies prior to the outbreak of Alzheimer's disease. In Alzheimer's dementia, pathology of synapses is preferably correlated with neuropsychological deficits. Findings on this pathology are discussed as a possible expression of a neuronal plasticity decrease that is partly conditioned by psychobiological mechanisms.