Parkin does not go into any of the underlying biological models of memory acquisition and retention. Since this book was published in 1993, there have been considerable advances in the biology. Instead, the book is pitched towards the higher levels of systems and clinical tests. Many experimental studies are summarised, and placed within an overall coherent and simple to understand framework.
Different models of memory as discussed, along with how these are supported (or not) by experimental evidence. An interesting section is on the short term working memory. We see how this functions like a scratch pad. And we see its limitations. Along with speculations as to how it differs from long term memory.