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Experimental Psychology – PSY402 VU LESSON 09
Memory Process: Encoding, Storage and Retrieval In psychology, memory is an organism's mental ability to store, retain and recall information. Suppose in your entrance test of BS psychology you are asked about the first experimental psychologist. As you track your brain for the answer, several fundamental processes relating to memory come into play. For instance your difficulty in answering the question may be traced to the initial encoding stage of memory. Encoding refer to the process by which information is initially recorded in a form useable to memory. You may never have been exposed to the information related to experimental psychology or if you have expose to it may have simply not registered in a meaningful way.
On the other hand even if you have been expose to the information you may still be unable to recall it because of failure in retention process. Memory specialists speak of the storage the maintenance of the material saved in the memory system. If the material is not stored adequately, it can not be recalled later.
Memory also depends on one last process: retrieval. In retrieval, material in memory storage is located, brought in to awareness and used. Your failure to recall may rest on your inability to retrieve the information that you have learned earlier
In sum, psychologists consider memory as the process by which we encode, store and retrieve information
The Three Systems of Memory: Memory Store Houses The Information Processing Model
Sensory memory Sensory memory corresponds approximately to the initial 200 - 500 milliseconds after an item is perceived. The ability to look at an item, and remember what it looked like with just a second of observation, or memorization, is an example of sensory memory. With very short presentations, participants often report that they seem to "see" more than they can actually report. The first experiments exploring this form of sensory memory were conducted by George Sperling (1960) using the "partial report paradigm." Subjects were presented with a grid of 12 letters, arranged into three rows of 4. After a brief presentation, subjects were then played either a high, medium or low tone, cuing them which of the rows to report. Based on these partial report experiments, Sperling was able to show that the capacity of sensory memory was approximately 12 items, but that it degraded very quickly (within a few hundred milliseconds). Because this
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Experimental Psychology – PSY402 VU form of memory degrades so quickly, participants would see the display, but be unable to report all of the items (12 in the "whole report" procedure) before they decayed.
Short term memory Short-term memory allows one to recall something from several seconds to as long as a minute without rehearsal. Its capacity is also very limited: George A. Miller (1956), when working at Bell Laboratories, conducted experiments showing that the store of short term memory was 7±2 items (the title of his famous paper, "The magical number 7±2"). Modern estimates of the capacity of short-term memory are lower, typically on the order of 4-5 items, and memory capacity can be increased through a process called chunking. For example, if presented with the string:
FBIPHDTWAIBM People are able to remember only a few items. However, if the same information is presented in the following way:
FBI PHD TWA IBM People can remember a great deal more letters. This is because they are able to chunk the information into meaningful groups of letters. Beyond finding meaning in the abbreviations above, Herbert Simon showed that the ideal size for chunking letters and numbers, meaningful or not, was three. This may be reflected in some countries in the tendency to remember phone numbers as several chunks of three numbers with the final four-number groups generally broken down into two groups of two. Working memory is part of short term memory. it is a system for temporarily storing and managing the information required to carry out complex cognitive tasks such as learning, reasoning, and comprehension. Working memory is involved in the selection, initiation, and termination of information-processing functions such as encoding, storing, and retrieving data. One test of working memory is memory span, the number of items, usually words or numbers, that a person can hold onto and recall. In a typical test of memory span, an examiner reads a list of random numbers aloud at about the rate of one number per second. At the end of a sequence, the person being tested is asked to recall the items in order. The average memory span for normal adults is 7 items.
Long term memory The storage in sensory memory and short-term memory generally has a strictly limited capacity and duration, which means that information, is available for a certain period of time, but is not retained indefinitely. By contrast, long-term memory can store much larger quantities of information for potentially unlimited duration (sometimes a whole life span). For example, given a random seven-digit number, we may remember it for only a few seconds before forgetting, suggesting it was stored in our short-term memory. On the other hand, we can remember telephone numbers for many years through repetition; this information is said to be stored in long-term memory. While short-term memory encodes information acoustically, long-term memory encodes it semantically: Baddeley (1966) discovered that after 20 minutes, test subjects had the least difficulty recalling a collection of words that had similar meanings (e.g. big, large, great, huge). Short-term memory is supported by transient patterns of neuronal communication, dependent on regions of the frontal lobe and the parietal lobe. Long-term memories, on the other hand, are maintained by more stable and permanent changes in neural connections widely spread throughout the brain. The hippocampus is essential (for learning new information) to the consolidation of information from short-term to long-term memory, although it does not seem to store information itself. Without the hippocampus, new memories are unable to be stored into long-term memory, and there will be a very short attention span. Furthermore, it may be involved in changing neural connections for a period of three months or more after the initial learning. One of the primary functions of sleep is improving consolidation of information, as it can be shown that memory depends on getting sufficient sleep between training and test, and that the hippocampus replays activity from the current day while sleeping. A major goal of education is to help learners store information in long-term memory and to use that information on later occasions in order to effectively solve problems.
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Experimental Psychology – PSY402 VU Types of Long Term Memory There are actually three different types (or aspects or parts) of long-term memory.
Episodic memory refers to our ability to recall personal experiences from our past. When we recount events that happened during our childhood, a ballet we saw last week, or what we ate for breakfast, we are employing our long-term episodic memory. As its name suggests, this aspect of memory organizes information around episodes in our lives. When we try to recall the information, we attempt to reconstruct these episodes by picturing the events in our minds. Episodic memory enables us to recall not only events, but also information related to those events. For example, a baseball coach faced with an unusual situation requiring a rule interpretation might think like this: "I remember a similar situation in a professional baseball game... When was it...? Last year... Reds vs. Giants... It was a night game, and the Giants had runners on first and second, when a line drive bounced and hit the umpire... What was the call...? I think they gave the batter a single and let the runners advance one base.... But I thought when the ball hit the umpire it remained in play.... Now I remember! If the umpire is in front of the fielders, it's a dead ball and a single. If the umpire would have been behind the fielder, it would have remained in play...." Apparently, recalling memorable episodes enables us to retrieve details that would otherwise be forgotten.
Semantic memory stores facts and generalized information. It contains verbal information, concepts, rules, principles, and problem-solving skills. While episodic memory stores information as images, semantic memory stores information in networks or schemata. Information is most easily stored in semantic memory when it is meaningful - that is, easily related to existing, well-established schemata. When we retrieve information from schematic memory, we mentally follow paths like those shown in Figure 6.1. By using information on numerous occasions after it has been initially learned, we solidify the connections among elements of information, make it easier to retrieve when we need to use it, and make it more likely that this information will be available to help us accept and store additional information in the future.
Procedural memory refers to the ability to remember how to perform a task or to employ a strategy. The steps in various procedures are apparently stored in a series of steps, or stimulus-response pairings. When we retrieve information from procedural memory, we retrieve one step, which triggers the next, which triggers the next, etc.
These various parts of long-term memory do not operate in isolation from one another. While it is not clear how they work together, it is clear that they are related and overlap. For example, a teacher who is asked to write a letter of recommendation for a former student might wish to retrieve information about the ability of that student compared to other students. To do this, she might first use episodic memory to form an image of that student as a real person performing real activities in her class several years ago, and this image might help her recall specific details of class performance and term papers written by that student. Likewise, a college student writing a paper in a history course on mercantilism might first listen to or read a semantic presentation on the topic, perform an episodic memory search to recall instances in his own life when he himself experienced what the teacher was talking about, recall the semantic definitions of related terms from another course, and continue this process until he felt he could understand and integrate the new information.
There are two major problems related to the use of long-term memory: (1) to transfer the information accurately to long-term memory and (2) to retrieve the information accurately. The primary strategy for transferring information from working memory into long-term memory is referred to as encoding or elaboration. These terms refer to the process of relating information to other information that is already stored in long-term memory. Piaget and other constructivists have developed detailed theories regarding how information is stored in long-term memory, and some aspects of these schemata theories are described in Chapter 4 of this book. That information should be considered directly compatible with the information presented in this chapter
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Experimental Psychology – PSY402 VU References http://en.wikipedia.org/wiki/Memory http://www.nwlink.com/~donclark/hrd/learning/memory.html http://education.calumet.purdue.edu/vockell/EdpsyBook/Edpsy6/edpsy6_long.htm
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