Explain why distant, well-rehearsed memories tend to remain strikingly well preserved even as recent memory deteriorates markedly under Ribot's law.

Distant, well-rehearsed memories, such as those from childhood, can remain strikingly well preserved even as recent memory deteriorates markedly, a pattern that reflects how memories become more deeply consolidated and less dependent on the specific, more vulnerable brain systems involved in recent memory formation the longer they have existed and the more often they have been recalled and reinforced over a lifetime. Recent memories, by contrast, have had less time to become consolidated in this way, making them more vulnerable to early disruption as a progressive brain disease takes hold. This matters clinically because recognising this characteristic pattern, rather than assuming memory loss is uniform across all time periods, helps a clinician both anticipate the likely course of a progressive illness and, in some cases, distinguish it from other patterns of memory disturbance in which the loss does not follow this same recent-before-remote gradient.