orking Memory holds a limited number of sounds and unless rehearsed they decay within seconds. The second component visuospatial sketchpad stores visual and spatial information and like phonological loop the capacity of the sketchpad too is limited. The third component, which Baddeley calls the Central Executive, organises information from phonological loop, visuospatial sketchpad as well as from the long-term memory. Like a true executive, it allocates attentional resources to be distributed to various information needed to perform a given cognitive operation and monitors, plans, and controls behaviour.
memory stores. As suggested earlier, all informations which our senses receive are not registered; if that be the case, imagine the kind of pressure that our memory system will have to cope with. Only that information which is attended to enters the STM from sensory registers and in that sense, selective attention, as you have already read in Chapter , is the first control process that decides what will travel from sensory registers to STM. Sense impressions, which do not receive attention, fade away quickly.
The STM then sets into motion another control process of maintenance rehearsal to retain the information for as much time as required. As the name suggests, these kinds of rehearsals simply maintain information through repetition and when such repetitions discontinue the information is lost. Another control process, which operates in STM to expand its capacity, is Chunking . Through chunking it is possible to expand the capacity of STM which is otherwise + .
For example, if you are told to remember a string of digits such as 194719492004 (note that the number exceeds the capacity of STM), you may create the chunks as , , and and remember them as the year when India became independent, the year when the Indian Constitution was adopted, and the year when the tsunami hit the coastal regions of India and South East Asian countries. From the STM, information enters the long- term memory through elaborative rehearsals . As against maintenance rehearsals, which are carried through silent or vocal repetition, this rehearsal attempts to connect the ‘to be retained