According to Baddeley's model of working memory, working memory is composed of three parts. First is the central executive which is responsible for a range of regulatory functions including attention, the control of action, and problem solving. Second, the phonological loop, which is specialized for the manipulation and retention of material in particular informational domains. Finally, the visuospatial sketchpad stores material in terms of its visual or spatial features. The strength of the relationships between the three components of working memory vary; the central executive is strongly linked with both the phonological loop as well as the visuospatial sketchpad which are both independent of each other. Some evidence indicates linear increases in performance of working memory from age 3–4 years through to adolescence. Central Executive Central executive is an integral of the working memory, and involves the all- inclusive attentional control of the working memory system. Initially Kail and Saweikis inferred that the central executive had an important role of storing some information and that the central executive reinforced long-term memory and has the potential to designate resources for focusing, dividing and switching attention. Currently the model of the central executive excludes the possibility of any type of memory storage. However, it does include the understanding that it does have a responsibility for the control and reinforcement of attention. In children from 2–4, the memory storage capacity limitation constrains complex comprehension processes. As the child grows older however, less processing is necessary which opens more storage space for memory. Phonological Loop Evidence indicates linear increases in performance from age 4 years through to adolescence. Prior to about 7 years of age, serial recall performance is mediated by the phonological store which is one of two components of the phonological loop. Preschool aged children do not use a subvocal rehearsal strategy to maintain decaying phonological representations in the store but instead they identify visual features of pictures in order to remember them. This is evident first by watching children for overt sign of rehearsal (for example lip movement) and second if the child is given nameable pictures, there are no differences in retrieval found for long versus short words. At the age of seven, children begin to use a subvocal rehearsal process to maximize retention in the phonological store. As development continues, nonauditory memory material is recoded into a phonological code suitable for the phonological loop when possible. Visuospatial Sketchpad Younger