Hockenbury Discovering Psychology 5th txtbk

242 CHAPTER 6 MemoryEpisodic MemoryEvents you have experiencedExplicit Memory(Declarative Memory)Memory with conscious recallFigure 6.5 Types of Long-Term MemoryLong-Term MemorySemantic MemoryGeneral knowledge, factsImplicit Memory(Nondeclarative Memory)Memory without conscious recallProcedural MemoryMotor skills, actionsHere’s the point: Your ability to type thephrase “most zebras cannot be extravagant”without looking demonstrates thatyou do know the location of the letters Z,X, C, V, B, N, and M. But your inability torecite that knowledge demonstrates thatyour memory of each key’s location cannotbe consciously recollected. Eventhough you’re not consciously aware ofthe memory, it still affects your behavior.Implicit memories are also called nondeclarativememories, because you’re unableto “declare” the information. Proceduralmemories, including skills and habits, typicallyreflect implicit memory processes.Figure 6.5 summarizes the different typesof long-term memory.Although much of the memory research covered in this chapter centers onexplicit memory, psychologists and neuroscientists have become increasinglyinterested in implicit memory. As we’ll see in a later section, there is growing evidencethat implicit memory and explicit memory involve different brain regions(Thompson, 2005). Some memory theorists believe that implicit memory andexplicit memory are two distinct memory systems (Kihlstrom & others, 2007;Tulving, 2002).Figure 6.6 Clustering DemonstrationStudy the words on this list forone minute. Then count backward bythrees from 108 to 0. When you’vecompleted that task, write down asmany of the words from the list asyou can remember.clusteringOrganizing items into related groups duringrecall from long-term memory.semantic network modelA model that describes units of informationin long-term memory as being organized ina complex network of associations.The Organization of Information in Long-Term MemoryExactly how information is organized in long-term memory is not completelyunderstood by memory researchers. Nonetheless, memory researchers know thatinformation in long-term memory is clustered and associated.Clustering means organizing items into related groups, or clusters, during recall. Beforereading further, try the demonstration in Figure 6.6. Even though the words arepresented in random order, you probably recalledgroups of vehicles, fruits, and furniture. In other words,chairboatfootstoolorangepearpeachbedbustrainplumgrapesmotorcycleapplecarairplanelampbananadressersofabookcasetrucktablestrawberrybicycleyou organized the bits of information by clusteringthem into related categories.Different bits and pieces of information in longtermmemory are also logically linked, or associated.For example, what’s the first word that comes to yourmind in response to the word red? When we asked ourstudents that same question, their top five responseswere “blue,” “apple,” “color,” “green,” and “rose.”Even if you didn’t answer with one of the same associations,your response was based on some kind oflogical association that you could explain if asked.Memory researchers have developed several models to show how information isorganized in long-term memory. One of the best-known models is called thesemantic network model (Collins & Loftus, 1975). When one concept is activatedin the semantic network, it can spread in any number of directions, activating otherassociations in the semantic network. For example, the word red might activate“blue” (another color), “apple” or “fire truck” (objects that are red), or “alert” (asin the phrase, “red alert”). In turn, these associations can activate other concepts inthe network.The semantic network model is a useful way of conceptualizing how informationis organized in long-term memory. However, keep in mind that it is just a metaphor,not a physical structure in the brain. Nevertheless, the fact that information isorganized in long-term memory has important implications for the retrieval process,as you’ll see in the next section.