Working Memory

Working Memory

1. Short-term memory or working memory as the gateway between perception and long-term memory

2. It comprises a coherent collection of specialized cognitive functions:

   • One group of functions enables temporary storage of the visual appearance of objects and scenes (the visual cache)
   • A second group likewise offers temporary retention of verbal material in terms of sounds or 'phonology' (the phonological loop)
   • A third offers a coordinating executive function which enables the conscious manipulation of information (central executive)

3. Basics of working memory

   • Basic features of a usable working memory:
     • Its limited capacity
     • The temporary nature of working memory
   • The contents of working memory can be combined with stored knowledge and manipulated, interpreted and recombined to develop new knowledge, assist learning, form goals, and support interaction with the physical environment.

4. Visual appearance and location

   • To suggest that we have a temporary memory that can hold information about where objects are and what those objects are
   • Allowing us to guide hand and arm movements to the correct location and to pick up the objects in the absence of vision
   • Allowing us to recall and describe the physical appearance or layout of familiar environments, such as the inside of our living room or the main square of our home town.

5. Memory span, counting and language acquisition

   • Any activity that requires retention of a verbal sequence such as remembering a new telephone number long enough to dial it, repeating a foreign word or counting objects would rely on this aspect of working memory
   • Memory span for digits is severely disrupted if the experimental participant is required to repeat aloud an irrelevant word
   • Digit span is language specific, and we should be cautious when interpreting digit span scores across languages and cultures
   • Counting and mental arithmetic
     • If we are counting objects, such as coins or number of events, we continually have to update our mental record of where we are in the counting sequence.
     • If we are counting an array of objects, such as words on this page, then we have in addition to keep track of which words have been counted and which have not.
   • Articulatory suppression had a dramatic effect on counting. Participants rarely achieved the correct total, although they could do so if they were not repeating an irrelevant word.
   • Mentally repeating the numbers is crucial for keeping track in a counting task, and this mental repetition comprises the subvocal rehearsal com ponent of the phonological loop.
     • The phonological loop component of working memory has proved useful in studies of language acquisition in young children
       • The ability to repeat an unfamiliar speech sound is important for acquiring vocabulary and other language skills, both in young children and in adults learning a second language
       • The loop has also been found invaluable in interpreting the pattern of difficulties encountered by brain-damaged patients who show deficits of one component of working memory while having other components intact

6. Long-term working memory

   • Working memory should offer temporary memory for immediate past experience, plus some means to mentally represent the immediate environment and to manipulate and continually update the contents of that mental representation
   • It should support the acquisition of new knowledge, problem solving and decision making knowledge accumulated over our lifetime is clearly available to each of us
   • The greater our expertise in a particular domain, the greater is our working memory capacity for information in that domain
   • The expert knowledge allows very efficient coding and retrieval of information within the area of expertise
     • Expertise greatly facilitates activation of relevant information in the knowledge base, and this activated knowledge can offer significant support for the more limited temporary working memory system