Memory • Memory is a general term for the storage, retention and recall of events, information and procedures. • The quality of an individual’s memory may vary based upon the nature of the information being retained and recalled, the level of interest in it, and its significance to that individual.
Module 7.1 • Varieties of Memory
Ebbinghaus’s Pioneering Studies of Memory • Hermann Ebbinghaus studied his own ability to memorize new material • He invented over 2300 nonsense syllables and put them into random lists. • Over 6 years he memorized thousands of lists of nonsense syllables. • Generally he found that delay between memorization and recall resulted in the forgetting of a large portion of the material.
Figure 7.1 Hermann Ebbinghaus pioneered the scientific study of memory by observing his own capacity for memorizing lists of nonsense syllables.
Ebbinghaus’s Pioneering Studies of Memory • Role of interference • Part of the difficulty for Ebbinghaus may have been the fact that he memorized so many lists of nonsense syllables. • If an individual learns several sets of related materials, the retention of the old material makes it harder to retain new material, and the learning of the new materials makes it harder to retain the old. • This phenomenon is known as interference.
Ebbinghaus’s Pioneering Studies of Memory • Role of interference • When retaining old material makes it hard to retain new material, this is called proactive interference. • When learning new material makes it hard to retain old material, this is called retroactive interference. • The problem for Ebbinghaus was that he had memorized so many lists of nonsense syllabus that he experienced a strong effect from proactive interference.
Concept Check You answer the telephone at your new receptionist job with the name of the your former employer’s firm. What kind of interference caused this embarrassing slip-up? Proactive interference
Ebbinghaus’s Pioneering Studies of Memory • Meaningfulness • Another feature of the pioneering work of Ebbinghaus is that he memorized nonsense syllables. • It is clear from studies of memory that meaningful materials are easier to remember. • It is also true that distinctive or unusual information is easier to retain. • The tendency of people to remember unusual items better than more common items is called the von Restorff effect.
Ebbinghaus’s Pioneering Studies of Memory • Dependence of memory on the method of testing • It is possible that since Ebbinghaus required himself to repeat the syllables in correct order after memorizing them, he underestimated his actual retention of the information. • How well one appears to remember something depends in part on how one is tested after learning.
Ebbinghaus’s Pioneering Studies of Memory • Dependence of memory on the method of testing • Recall (or free recall) is the simplest method for the tester but the most difficult for the person being tested. To recall something is to produce it, as is done on essay and short-answer tests. • Cued recall gives the person being tested significant hints about the correct answer. A fill-in-the-blank test uses this method.
Ebbinghaus’s Pioneering Studies of Memory • Dependence of memory on the method of testing • Recognition is the method that requires the person being tested to identify the correct item from a list of several choices. Multiple-choice tests use the recognition method. • The savings, or relearning method compares the rate at which someone relearns material as opposed to learning something new. The amount of time saved between the original learning and the relearning is a measure of memory.
Ebbinghaus’s Pioneering Studies of Memory • We are indebted to Ebbinghaus for initiating the scientific study of memory. • We have also learned important facts about the nature of memory from his difficulties with interference.
Concept Check The bonus question on your Introductory Psychology test asks you to name the stages of the human sleep cycle. Recall
Concept Check You are on a game show and the question that you must answer is “_________ is the city that is home to the Eiffel Tower, the Louvre, and the Cathedral of Notre Dame.” Cued recall
Concept Check You answer more questions on the subject of molecular biology correctly on the comprehensive semester final than you did on the chapter test two months earlier. Relearning or Savings
Concept Check While at a hardware store, you are looking at several shades of light green paint in hopes of repainting the walls of your home in that exact shade. Recognition memory
The Information-Processing View of Memory • The information-processing model of memory draws an analogy between a computer and the workings of memory in the human brain. • According to this view, information enters the system, is processed and coded in various ways, and is then stored.
Figure 7.4 The information-processing model of memory resembles a computer’s memory system, including temporary and permanent memory.
The Information-Processing View of Memory • The computer has a “buffer” – a temporary storage place for letters that you type faster than it can display them. • This is akin to our sensory memory store
The Information-Processing View of Memory • The computer has RAM, or random-access memory, for temporary storage of information that has not yet been written to the hard drive. This information is still vulnerable to damage or loss. • This is analogous to our short-term, or working memory.
The Information-Processing View of Memory • The computer has a hard drive, in which information that you are writing or entering can be permanently stored. • This is like our long-term memory.
The Information-Processing View of Memory • The sensory store • Although it is probably more accurately described as a combination of memory and perception, the sensory store is considered to be the first stage of memory processing. • It is a very brief (less than a second) stage that registers everything that is perceived in the moment that we call “now.”
Figure 7.5 George Sperling (1960) flashed arrays like this on a screen for 50 milliseconds. After the display went off, a signal told the viewer which row to recite.
The Information-Processing View of Memory • Short-term and long-term memory • Temporary storage of information that someone has just encountered is short-term memory. • Long-term memory is a relatively permanent storage of mostly meaningful information. • Reminders or hints that help us to retrieve information from long-term memory are referred to as retrieval cues.
The Information-Processing View of Memory • Short-term memory • If a friend asks you what he or she just said, and you were paying attention, you could probably repeat their words or something close to them. • This is because you are being asked to recall something from short-term memory. • If you were not paying attention, you would not recall it at all. Attention is the process that moves information from the sensory store to short-term memory.
Table 7.3 After about 1 second, you can no longer recall information from the sensory store. Short-term memories can be recalled up to about 20 seconds without rehearsal—much longer if you continually rehearse them. Long-term memories decline somewhat, especially at first, but you may be able to retrieve them for a lifetime. Your address from years ago is probably in your long-term memory and will continue to be for the rest of your life.
The Information-Processing View of Memory • Long-term memory • If your psychology instructor asks you to name the function of the thalamus, your first reaction might be to panic because you have no idea. • The instructor says, “It has something to do with sensory information, right?”
The Information-Processing View of Memory • Long-term memory • Then it begins to come back to you – the thalamus is a relay and integration station for sensory information on its way to the cerebral cortex. • The instructor gave you a hint that functioned as an effective retrieval cue. These cues can be generated internally or be suggested by others.
The Information-Processing View of Memory • Capacities of short and long-term memory • Most normal adults can immediately repeat a list of about seven bits or pieces of information, with expected variations in range from five to nine items. • This “magic range” of 7 +/- 2 bits is a well-replicated finding regarding the capacity of short-term memory. • It can be expanded through techniques such as chunking into larger, meaningful units.
Figure 7.6 We overcome the limits of short-term memory through chunking. You probably could not remember the 26-digit number in (a), but by breaking it up into a series of chunks, you can remember it and dial the number correctly.
The Information-Processing View of Memory • Capacities of short and long-term memory • The capacity of long-term memory cannot easily be measured. • Unlike a computer, we are not dealing with a physical limit of size. • Humans are constantly dumping or removing some of their stored information through disuse.
The Information-Processing View of Memory • Decay of short and long-term memory • Information that has been stored in long-term memory may be vulnerable to the aforementioned effects of interference, but it generally does not decay due to the effects of time alone. • Information being held in short-term memory is vulnerable immediately to the effects of the passage of time. • Forgetting tends to begin in seconds unless rehearsal is permitted.
Figure 7.9 In a study by Peterson and Peterson (1959), people remembered a set of letters well after a short delay, but their memory faded greatly over 20 seconds if they were prevented from rehearsing during that time.
The Information-Processing View of Memory • Capacities of short and long-term memory • How long one is able to hold information in short-term memory has little relationship to how well it will be stored in long-term memory. • If the information being held in short-term memory is meaningful, it will be transferred easily to long-term memory and be less subject to decay. • Up until recently, cognitive psychologists referred to this transfer process as consolidation, the formation of a long-term memory.
The Information-Processing View of Memory • Capacities of short and long-term memory • It is now thought that how easily information is consolidated depends on its meaningfulness to the individual. This idea implies that perhaps the division between the short and long-term memory stages is at least in part an artificial one. • If the information is meaningful, the groundwork for storing that information has already been done.
The Information-Processing View of Memory • Working memory • Working memory is a revised concept of the intermediate stage between our first encounter with new information and its eventual storage. • Working memory is a system for processing or working with current information. • Working memory is conceptualized as having three major components.
The Information-Processing View of Memory • Working memory’s 3 components: • A phonological loop that stores and rehearses information, similar to the 7 +/- 2 idea from the traditional concept of short-term memory. • A visuospatial sketchpad that stores and manipulates visual and spatial information. • A central executive that governs shifts of attention. Good working memory is able to handle shifts between two or more tasks or multiple aspects of complex tasks.
The Information-Processing View of Memory • Other memory distinctions • Declarative memory is the ability to state a fact. • Procedural memory is the memory of how to do something. • Long-term declarative memory is classified as either semantic (dealing with principles of knowledge) or episodic (containing events and details of life history.) • Your memory of a recent piano lesson is declarative and episodic; your memory of how to read music is semantic; your memory of how to play the piano is procedural.
The Information-Processing View of Memory • Other memory distinctions • A normal type of forgetting is source amnesia. • This involves a combination of episodic and semantic memory. We remember a statement or knowledge related (semantic) fact but we forget the context in which we learned it.
The Information-Processing View of Memory • Other memory distinctions • The context in which one learns information is episodic. • It can be inferred from the occurrence of this phenomenon that episodic memory is more fragile than semantic knowledge.
Varieties of Memory • Although there is still much disagreement about the nature of memory, there is general agreement that memory is not a single store into which we dump the sum of our knowledge and experiences.
Varieties of Memory • Memory is a complex combination of many processes, and its properties depend on a number of factors • The type of material memorized • The individual’s experience with similar materials • The method of testing • The length of time since the material was encountered
Module 7.2 • Long Term Memory Storage
Memory Improvement • To improve memory, one must improve the strategies used to originally store the material.
The Influence of Emotional Arousal • It is well understood that the greater the emotional arousal associated with an event, the greater the likelihood that the event will be remembered. • Although the event itself may be remembered, the emotion associated with the event does not guarantee the formation of an accurate memory for the details of the event.
The Influence of Emotional Arousal • During stressful or emotional events, the sympathetic nervous system works to boost production of the hormones cortisol and adrenaline. • This is usually accompanied by increased stimulation of the amygdala. • The net effect of these processes is to enhance memory storage of information associated with emotional or stressful events.
Concept Check A Vietnam War Veteran who was involved in several very intense and violent campaigns has been medically monitored for years. He has lower than normal levels of cortisol. How would this affect his memory? • He should report frequent memory lapses.
Meaningful Storage and Levels of Processing • The levels-of-processing principle • The levels-of-processing principle states that the ease with which we can retrieve a memory depends on the number and types of associations that we form with that memory • The more ways in which you think about the material, the deeper your processing will be and the more easily you will remember the material later.