Anterograde Amnesia - Pathophysiology

Pathophysiology

The pathophysiology of anterograde amnesic syndromes varies with the extent of damage and the regions of the brains that were damaged. The most well-described regions indicated in this disorder are the medial temporal lobe (MTL), basal forebrain, and fornix. Beyond the details described below, the precise process of how we remember — on a micro scale — remains a mystery. Neuropsychologists and scientists are still not in total agreement over whether forgetting is due to faulty encoding, accelerated forgetting, or faulty retrieval, although a great deal of data seem to point to the encoding hypothesis. In addition, neuroscientists are also in disagreement about the length of time involved in memory consolidation. Though most researchers, including Hasselmo et al., have found the consolidation process is spread out over several hours before transitioning from a fragile to a more permanent state, others, including Brown et al., posit that memory consolidation can take months or even years in a drawn-out process of consolidation and reinforcement. Further research into the length of time of memory consolidation will shed more light on why anterograde amnesia sometimes affects some memories gained after the event(s) that caused the amnesia, but does not affect other such memories.