| Chapter 1: | Study One: Introduction / Overview of Study Goals |
Memory has also been defined in terms of how it is structured. Traditionally, a multi-store model of memory has been widely accepted among scholars. Long-term (LTM) and short-term memory (STM) are generally considered to be two forms of storage in such a model. Typically short-term memory is considered to have a limited capacity of about seven, plus or minus, two items (Miller, 1956), and it serves as a storage space for processing information (Glanzer, 1972). Long-term memory, on the other hand is a storage space where more information is held for a considerably longer time. Although STM and LTM are often considered to be two separate storage spaces, researchers have also argued that they can be viewed as elements on a continuum (Melton, 1963) and that information can often be held in both stores simultaneously (Waugh & Norman, 1965).
The Atkinson–Shiffrin (A–S) model is one of the most well known models of human memory from a multi-store perspective. Atkinson and Shiffrin drew on the earlier work of Broadbent and Neisser who also suggested multi-store systems of memory (Lachman, Lachman, & Butterfield, 1979). Similarly, Waugh and Norman’s (1965) memory model is also a precursor to the A–S model. Waugh and Norman suggested a two-store model distinguishing between long-term and short-term memory by discussing them asprimaryandsecondarymemory (these terms were originally used by James, 1890, as indicated in Waugh & Norman, 1965). The model outlined a process whereby rehearsal of information in the limited primary store could transfer that information into the larger and more stable secondary store. It should be noted here that although the A–S model is not the first multi-store model, it is a very heavily cited model in experimental psychology (Izawa, 1999).
The Atkinson and Shiffrin model is a three-part memory model consisting of the sensory register, the short-term store and the long-term store (Atkinson & Shiffrin, 1968). The sensory register receives auditory and visual stimuli through our senses. The short-term store (STS; also referred to as the working memory) is where information is held before it is either lost or transferred into the long-term store (LTS).