These components were so-called the Visuo-Spatial Sketchpad and the Phonological Loop. Baddeley and Hitch suggested that these two subsystems were governed by central controlling mechanism, which they termed the Central Executive. The Phonological Loop acts like an inner ear and operates like the loop of an audiotape. It can hold spoken information for about 1-2 seconds. Written words must be transferred into spoken words in order to enter the phonological loop.
Its input is from eyes or the LTM. The phonological loop consists of two sub- systems; the phonological store, “the inner ear”, which allows acoustically coded information to be stored for a brief period of time (about two seconds), and the articulatory control system, “the inner voice”, which helps maintain information by sub-vocal information. The phonological loop also has a limited capacity. In 2000, Baddeley introduced a new component to the WMM: the episodic buffer. Its purpose is to organize the information received from the other components with information about time and order.
Kahneman (as cited in Edgar, 2007) explains it in the limited capacity theory of attention. According to it, “the brain contains limited-capacity central processor responsible for analyzing incoming information and integrating it to information already held in memory” (Edgar, 2007, pp.11). Thus, when a person tries to do many things at once interference can occur if those things compete for the same pool of resources. However, Macleod (as cited in Edgar, 2007) showed that it is possible to do two things at once without interference. In his study, participants had to carry out a visual and an auditory task and respond to them by saying ‘bip’.
The articulator loop and the visuo-spatial sketch pad are responsible for short term maintenance of information and the central executive is responsible for coordinating these two systems. The articulatory loop stores phonetic information, for example numbers that we repeat to ourselves as soon as we learn them and the visual-spatial sketch pad stores visual and spatial information. The central executive is responsible for processing the information gathered by the other two components and determining which information is relevant. Another model proposed by Graeme Halford suggests that short term memory can be better defined as the ability to create or distinguish relationships between items or elements. For example in the following sentence "In metropolitan areas budget hotels charge excessively for internet access whereas expensive hotels in seaside resorts charge more
In addition information in the short term memory store is encoded acoustically; this theory is supported by Conrad’s 1964 case study where an experiment was conducted that confirmed Atkinson and Shiffrin’s theory that the STM encodes information acoustically. Their findings showed after rehearsal the info is transferred from the STM to Long term memory store if not rehearsed information is lost through decay. When in the LTM, the material can last for up to a lifetime when rehearsed or is of semantic value. LTM encodes information that is semantic. There are many strong points to consider in terms of the multi store model of memory.
We have sensory memory stores where information from the outside world is taken in unconsciously so if it is not looked at consciously it can be lost via decay as the duration is very short (possibly up to 2 seconds). It is a brief memory of things we have seen (iconic memory) and things we have heard (echoic memory) which help us make sense of the world. We can hold sounds in our sensory memory for a couple of seconds allowing us to hear whole sentences in speech. The majority of information is lost but what we pay attention to is passed on to short term memory. All of our senses – sight, smell, touch, taste and hearing – have a separate store within sensory memory.
Short-term Memory (STM) or "Working Memory"(WM) In the Atkinson and Shiffrin model, information from the sensory memory enters the STM if it is attended to. The Short term memory is also called ‘working memory’ and holds a limited amount of information for a short period of time (about 18 seconds). Once information enters the short term memory it needs to be converted to a code. research indicates the most commonly used code is phonological/acoustic code (based on sound). At times however, encoding in WM may be visual as well as when some people remember the information in terms of images.
As Kandel (2000) points out, in either case the content of all explicit memories can be expressed by declarative statements such as “I was here yesterday” (episodic) and “The hippocampus has something to do with memory”(semantic). Implicit memory involves information about how to perform something; it’s recalled unconsciously. We use implicit memory in trained, reflexive motor or perceptual skills. I know how to drive my car; I know how to get to work. The same people with bilateral medial temporal lobe lesions can learn simple reflexive skills–they habituate and are sensitized, they can be classically and operantly conditioned (see later).
There are three types of memory which are sensory memory, short-term memory and long-term memory. “In 1956, US psychologist George Miller found short term memory is nearly always very close to seven. Nonetheless, in 2001, American psychologist Nelson Cowan argued that the capacity of short-term memory is much less than seven.”(Jarrett, 2011, p.148) Although chunking word seems like beneficial for remembering, not all the memory can be recalled voluntarily as some of the memories were locked by us and it called repression. However, there are something might cause them to unlock at a later time. “In 1915, Sigmund Freud first study repression which is the process of pulling thoughts into the unconscious and preventing painful or dangerous thoughts from entering consciousness; seemingly unexplainable naivety, memory lapse or lack of awareness of one’s own situation and condition.”(Furnham, 2012, p.145) On the other word, it is the defense mechanism to protect us.
Short-term memory refers to information-storage without manipulation and is therefore a component of working memory. Working memory differs from long-term memory, a separate part of the memory system with a vast storage capacity that holds information in a relatively more stable form. According to the multi-component model, working memory includes an executive controller that interacts with separate short-term stores for auditory-verbal and visuo-spatial information. The concept of working memory has proved useful in many areas of application including individual differences in cognition, neuropsychology, normal and abnormal child development and neuroimaging. The term working memory is used most frequently to refer to a limited capacity system that is capable of briefly storing and manipulating information involved in the performance