Amnesia is one disorder of memory, Anterograde amnesia is the inability to form new long term memories. Retrograde amnesia is the loss of memory for past events, and recall is usually worst for events occurring closest to the onset of amnesia.

Explicit memory which is where information can be deliberately and consciously recalled, and implicit memory where recollection is independent of conscious awareness. Furthermore,, there are different types of LTM’s, for example procedural memory is the acquisition of motor skills, i.e. knowing how to ride a bike which is an implicit memory and Declarative memory which is fact based i.e. knowing that you can ride a bike which is an explicit memory. Amnesiacs tend to have poor explicit memory and unimpaired implicit memory which this can account for normal performance on tests of procedural memory.

Evidence for this comes from the example of Clive Wearing who had damage to his hippocampus leaving him with only moment to moment memory. However, he could remember how to play the piano so his procedural memory was intact yet he could not remember that he could do so. This could be because the part of the brain responsible for procedural memories is the cerebellum and this was not affected in his case. Moreover procedural memories are stored in motor code rather than verbal code and this may make them less susceptible to decay.

A problem with case studies of human amnesiacs is that they involve a single individual and so findings cannot be generalised to all amnesiacs. An alternative approach, is lesioning animals’ brains and evidence from Remondes showed that rats with damage to the hippocampus could learn a maze but forgot it quickly, suggesting they could make new memories but couldn’t consolidate them in LTM suggesting the hippocampus is associated with consolidation. However, we should be cautious in applying