LEARNING OBJECTIVES • What is working memory? What age differences have been found in working memory?

Attention and Memory 193

• How does implicit and explicit memory differ across age?

• How does episodic and semantic memory performance differ across age?

• What age differences have been found in the autobiographical aspects of episodic memory?

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usan is a 75-year-old widow who feels that she does not remember recent events, such as whether she took her medicine, as well as she used to. She also occasionally forgets to turn off the gas on her stove and sometimes does not recognize her friend’s voice on the phone. However, she has no trouble remem­bering things from her 20s. Susan wonders if this is normal or whether she should be worried.

Memory researchers have long focused on three general steps in memory processing as potential sources of age differences: encoding, storage, and retrieval (Smith, 1996). Encoding is the process of getting information into the memory system. Storage involves the manner in which information is repre­sented and kept in memory. Getting information back out of memory is termed retrieval. Because there is no evidence for age differences in how information is organized in storage, most research has examined encoding and retrieval as sources of age differences (Light, 1996; Zacks, Hasher, & Li, 2000).

As discussed earlier, researchers have looked to research on speed of processing and impaired inhi­bition as providing insights into why age differences in memory occur. We will also add the process of working memory to this list. These mechanisms involve information that is being actively processed at any point in time, and they are aspects of mem­ory showing clear age differences. More recently, researchers have examined contextual features and social-emotional contextual factors that could account for age-related differences in memory. We will see that these approaches offer alternative explanations for changes in memory as we grow older.

Our focus in this section will be on two main components of memory: short-term memory, including both short-term capacity and working memory, and multiple processes of long-term mem­ory. The multiple processes of long-term memory are what Susan is most worried about. As we shall

194 CHAPTER 6 see, it is very common to have memory problems that involve remembering more recent episodes and events as opposed to more remote memories from the past.