Chapter 36 Structural changes in the normally aging cerebral cortex of primates

摘要: During normal aging humans exhibit some cognitive decline, but it is difficult to determine the underlying causes of this because information about status rarely available and preservation brain usually inadequate for detailed cytological examination. One solution problem use a nonhuman primate model, such as rhesus monkey, which exhibits age-related decline similar humans, can be cognitively tested before brains are preserved It now known that in human primates not due loss cortical neurons there no correlation between frequency senile plaques status. Indeed apart from layer 1, cerebral cortex show few signs aging, although may synapses throughout cortex. In contrast, both microglia astrocytes come contain phagocytosed material, its origin unknown. There also white matter, accompanied by breakdown myelin sheaths alterations oligodendrocytes. suggested changes alter conduction velocities along axons. This would timing neuronal circuits, contributing decline.