Models of memory -The multi- store model
What is a model?
Computer programmes mimic human cognitive functioning. These programmes need to highly specific and detailed. However computer is modelling is complex and time consuming. To compromise researchers use flow charts rather than develop programmes to represent their theories. Theories base on information- processing systems are known as models.
Short term memory is a temporary store where small amounts of information can be kept for brief periods. It’s a fragile store and information can easily be lost. Long term memory is a permanent store where limitless amounts of information can be stored for long periods of time.
Research study: Atkinson and Shiffrin model
Imagined memory as a flow of information through an information processing system. System is divided into a series of stages. There are restrictions at each stage in terms of capacity, duration and encoding which is the way information is represented in the memory store. The information first enters the system from the environment and registers on the sensory memory where it stays for a brief period of time. The short term memory store has a very small capacity. If not rehearsed it can be lost in a matter of seconds. Items in the short term memory are usually held as sounds. If item is sufficiently rehearsed it is passed on to long term memory. Once there can stay there for a lifetime although can be lost through damage or decay.
This model is a structural model because it focuses on the storage components of the system. One of the most important processes for their model is rehearsal.
Stimuli from the environment first registers in the sensory store. Hold information for a fraction of seconds. There are three separate sensory stores to accommodate different kind of input. Iconic store for visual input, things we see. Echoic store for auditory input, things we hear. Haptic store for tactile input, things we feel or touch.
The purpose of visual store is to allow integrate visual information to conscious level, so we experience smooth, continuous visuals. Another function of the sensory memory is to sift through huge amount incoming sensory information to avoid overloading the system.
Research study: Sperling 1960
A chart of three rows of letters is displayed for very brief exposure. Participants were asked to recall as many letters as possible. He decided to change the procedure slightly by training the participants to distinguish between three tones. He then exposed the chart for the same amount of time, played the tone as soon as the chart disappeared. Participants were instructed to recall top line if there was a high tone, middle line for middle tone and last line for low tone. Under these circumstances participants were able to recall, on average three letters. The advantage of a lab experiment is that there is a high level of control and that it can be replicated. However the stimuli used were artificial therefore may not reflect how we use…