Models for explaining human memory Psychologists tend to break memory down into components that can be studied separately from one another and consider how each component contributes to an understanding of the whole. A model is then used to represent, describe and explain memory and its components and processes. For the human memory a visual diagram is used to represent the movement of information and arrows to represent the movement of information from one component to another. THE ATKINSON-SHIFFRIN MULTI-STORE MODEL ASMSM- represents memory as consisting of three distinguishable components called sensory register, the short-term store and the long-term store. Each component represents a place where info is held and processed. See figure 6.5 in book on page 293 The three components are represented as separate memory stores through which info is received from the environment, it usually flows from the sensory register to the short term register to the long term register. Info may also flow the opposite way. Each component stores, encodes and processes info in different ways, but they operate simultaneously and interact. According to Atkinson and Shiffrin (1968) the sensory register is the entry point for all new info into memory from the external environment. Any info attended to is then sent to the short-term store and if not attended to it simply decays and disappears. In some cases, info may bypass the shortterm store and transfer directly to the long-term store, but this was explained by the researchers. They indicated it may occur as is there a possibility that there may be different sensory registers for different types of sensory info. One for visual and one for auditory. They described the short-term store as a ‘temporary working memory’ in which we manipulate info that is held to perform everyday functions. It holds all info that we are consciously aware of at any point of time. The STS receives inputs of info from the sensory register as well as info from long- term store. However, unlike the sensory register and long term store, it has a limited capacity, being able to hold up around seven items of info at the same time. Furthermore, info can only be held there for about 30 secs unless a conscious effort is made to keep it there longer. This can be achieved by rehearsal, where you repeat the info over and over again such as trying to remember a phone numer. Rehearsal is crucial as it allows the info to be further encoded and transferred to the long-term store for more permanent storage. If new info is not rehearsed then it decays and the info is lost forever. LONG TERM STORE is described as holding info relatively permanently in a highly organised way and having an essentially unlimited capacity. Unlike the sensory register and STS, info transferred to LTS does not usually decay and may be stored up to a lifetime. All info is eventually lost from the SR and STS. We can fail to retrieve info from our LTS and this is primarily a result from the use of ineffective search strategies to find the right memory trace for that information. The presence of related info in the LTS may also result in ‘interference’ with the sought-after info thereby disrupting the retrieval process. Structural features are the permanent , built-in fixed features of memory that do not vary from one situation to another. The three different stores are the basic structural features. Other structural features include : The function of each component (role it plays) The storage capacity of each component (the amt of info it can hold) The duration or length of time for which info can be held by each component IControl processes are selected and used by each individual and may vary across difft situations. They are under the conscious ‘control’ of the individual and which control process is used depends on what the individual does. Ie. Attention is a controlled process and if you decide to pay attention then the info will be transferred from SR to STS. Rehearsal is another control process and its use determines whether info is retained in STS and then transferred to LTS. Retrieval is a controlled process and the search chosen will determine the success of the retrieval or not. While some of their info still remains accurate such as storage, capacity and duration there has been updates which challenge the A & S model. There is considerable evidence that there is a separate sensory register for auditory info and haptic (touch) info as possibly one for the other senses as well. The sensory register is now called sensory memory. The short term store is now referred to as working memory is no longer believed to be a single store in which info is rehearsed until it flows into the long-term store or is discarded. Neuroimaging has shown that short-term memory consists of a number of separate, interacting components or sub-systems that process difft types of info. (Baddeley 2009) Researchers have also distinguished between difft types of rehearsal in stm. Maintenance rehearsal as described by A& S is still relevant, but simply simply repeating info does not guarantee transfer to LTM. Elaborative rehearsal better promotes encoding and is much more effective for long-term storage. Long Term Memory has different sub-systems or stores, such as episodic and procedural, each of which processes and stores difft types of info. Info is not retrieved exactly as we store them, we can construct or build on them as shown with ‘false memories’ . LA 6.4