summary of concepts

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© Bob Jacobson/Corbis

LO 1 Define memory. (p. 217)

Memory refers to the information collected and stored in the brain that is generally available for later use. Exactly how the brain absorbs information from the outside world and files it for later use is still not completely understood. However, scientists have proposed many theories and constructed various models to help explain how the brain processes, or works on, data on their way to becoming memories.

LO 2 Identify the processes of encoding, storage, and retrieval in memory. (p. 217)

Encoding is the process through which new information enters our memory system. Information is taken in by our senses and converted into neural activity that travels to the brain, and if successfully encoded, it is stored. Storage preserves the information for possible recollection in the future. Retrieval is the process of accessing information stored in memory.

LO 3 Explain the stages of memory described by the information-processing model. (p. 219)

According to the information-processing model, the brain has three types of memory storage associated with the stages of memory: sensory memory, short-term memory, and long-term memory. The levels of processing framework suggests there is a hierarchy of stages that corresponds to different depths of information processing.

LO 4 Describe sensory memory. (p. 221)

Data picked up by the senses enter sensory memory, where sensations are registered. Here, almost exact copies of our sensations are processed for a very brief moment. Information from the outside world floods our sensory memory through multiple channels. Although this stage of memory is fleeting, it is critical to the creation of memories.

LO 5 Summarize short-term memory. (p. 224)

Short-term memory is the second stage of the original information-processing model. This is where information is temporarily maintained and processed before moving on to long-term memory or leaving the memory system. Short-term memory has a limited capacity; how long and how much it can hold depends on how much you are distracted by other cognitive activities. Through maintenance rehearsal, we can prolong short-term memory.

LO 6 Give examples of how we can use chunking to improve our memory span. (p. 226)

Grouping numbers, letters, or other items into meaningful subsets, or “chunks,” is an effective strategy for juggling and increasing the amount of information in short-term memory. In addition, chunking can help nudge the same information into long-term memory.

LO 7 Explain working memory and how it compares with short-term memory. (p. 226)

The active processing component of short-term memory, working memory, has four important parts. The phonological loop is responsible for working with verbal information for brief periods of time. The visuospatial sketchpad is where visual and spatial data are briefly stored and manipulated. The central executive directs attention, makes plans, coordinates activities, and determines what information should be ignored. The episodic buffer is where information from the phonological loop, visuospatial sketchpad, and long-term memory can all be brought together temporarily, as directed by the central executive.

LO 8 Describe long-term memory. (p. 229)

Long-term memory is a stage of memory with essentially unlimited capacity. Long-term memories may be explicit or implicit. Explicit memory is the type of memory you are aware of having and can consciously express, and can be further divided into semantic and episodic memory. Semantic memory pertains to general facts about the world, while episodic memory is your record of the memorable experiences in your life. Implicit memory is for something you know or you know how to do, but that might be automatic or unconscious, and therefore difficult to articulate.

LO 9 Illustrate how encoding specificity relates to retrieval cues. (p. 235)

Retrieval cues are stimuli that help you retrieve stored information that is difficult to access. The encoding specificity principle states that memories are more easily recalled when the context and cues at the time of encoding are similar to those at the time of retrieval. Thus, the context (external or internal) at the time of encoding and retrieval provides retrieval cues. Priming, recall, and recognition also play a role in the retrieval of stored information.

LO 10 Identify some of the reasons why we forget. (p. 239)

Memory failure may occur during any of the three stages of memory processing: encoding, storage, and retrieval. One example of memory failure is the tip-of-the-tongue phenomenon, which occurs when we cannot retrieve a stored memory.

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LO 11 Explain how the malleability of memory influences the recall of events. (p. 243)

Eyewitness accounts are not always reliable because people’s memories are far from perfect. Memories can change over time, which means we should be careful when questioning people about crimes and other events they have witnessed. Studies on the misinformation effect suggest that information obtained after an incident can distort one’s memory of it.

LO 12 Define rich false memory. (p. 244)

Rich false memories are experienced as true recollections of an event, including details, emotions, and confidence that the event occurred, although it never did. Some researchers have implanted memories of events that never occurred.

LO 13 Compare and contrast anterograde and retrograde amnesia. (p. 247)

There are varying degrees of amnesia, or memory loss, due to medical or psychological conditions. Anterograde amnesia is the inability to “lay down” or create new long-term memories, and is generally caused by damage to the brain resulting from surgery, alcohol, head trauma, or illness. Retrograde amnesia is an inability to access memories created before a brain injury or surgery.

LO 14 Identify the brain structures involved in memory. (p. 249)

Researchers have identified many brain structures involved in the processing and storage of memory. The hippocampus is essential for creating new explicit memories, as are the temporal lobes and frontal cortex. Other areas, such as the cerebellum and amygdala, are integral in the processing of implicit memories.

LO 15 Describe long-term potentiation. (p. 252)

Long-term potentiation refers to the increased efficiency of neural communication over time, resulting in learning and the formation of memories. The communication among neurons improves and strengthens, allowing for new skills to develop and become more natural. These new pathways explain how a skill, for example, is learned and thus becomes an implicit memory.