CHAPTER 8 PSYCH 100 MEMORY Memory: The system that allows us to retain information and bring it to mind. Short-Term Memory Test Read the following list only, concentrating briefly for a few seconds on each word. Vase Tiger Book Cushion Piano Hat Teapot Camera Ice Cream Spade House Orange Short-Term Memory Test Recall the words: • Make a list of all the words that you can remember. How many can you recall? Short-Term Memory Test Here are the 12 words, how many did you get? Vase Teapot Tiger Camera Book Ice Cream Cushion Spade Piano House Hat Orange Memory: The system that allows us to retain information and bring it to mind. Remembering Information Processing Theory Encoding Storage Retrieval Encoding Memory encoding: process of converting information into a form that can be stored in memory. Must form a memory code from some stimulus. Three ways information can be encoded: • Acoustically (by sound, remembering a melody) • Visually (a visual image, remembering the arrangement of furniture in a room) • Semantically (by focusing on the meaning of the information, you remember a new vocabulary word by using it in a sentence) Storage • Putting things into memory would be useless process unless those data remain there (hopefully unchanged) over time. • Memory storage is where memories “hang out” until they are needed again in the future, at which time retrieval takes place. • Memory storage is the process of retaining information in memory Retrieval • Memory retrieval is the process of accessing and bringing into consciousness information stored in memory. • Retrieval cues are associated with the original learning that facilitate the retrieval of memories. These cues are stimuli that help gain access to memories. Retrieval • When you can not retrieve information and it feels as if it’s just out of your reach, you are experiencing the tip-of-the-tongue phenomenon. • This is a failure in retrieval, research shows that retrieval occurs more frequently when retrieval cues are present. • Context cues are types of retrieval cues that can aid our retrieval of memories. Working with context cues involves putting yourself in the context in which a memory occurred. Sensory Memory Short-Term Memory Long-Term Memory Memory researchers identify three time-based memory storage systems: sensory memory, short-term memory, and long-term memory. Like the computer example of memory, information processing is a metaphor – the three storage systems do not refer to tiny “lockers” in the brain where information actually sits. • Sensory memory is a temporary storage that preserves sensory impressions. • Information in sensory memory is held in a “sensory register. ” For visual information, this is called iconic memory (photographic memory). For auditory information it is called echoic memory (sound echo). • For vision and audition, sensory memories only last .25 of a second. • You can see sensory memory, called an afterimage, when a flashlight or sparkler is moved about quickly, creating what appears to be a continuous figure. A sound echo is another form of sensory memory. What’s great about sensory memory is that it allows us to experience a visual pattern, sound, or touch even after the event has come and gone. In doing this, sensory memory gives us additional time to recognize things and bring them into memory. Short-Term Memory • Short-term memory allows us to hold information in mind for ~30 seconds. • Also called working memory, and has a limited capacity, it can only store so much information at any one time. • Magic 7: Can only remember 7 numbers +- 2 digits • This was discovered by George Miller, when he found that most participants could only remember 7 numbers, plus or minus 2 digits. • When we need to memorize more than 7 numbers, plus or minus 2 digits, the information already stored in our short-term memory is displaced. • This is why we have methods of remember more information. • Maintenance rehearsal: practice! Chunking FBINBCCIAIBM FBI NBC CIA IBM • Rather than viewing information broken into bits, we can store multiple bits as chunks, a process known as chunking. • We can put these letters into meaningful, easyto-memorize units, such as FBI-CIA-NBC-IBM. Going from working with 12 letters to 4 pieces/chunks to remember. • Short-term memory can be extended (indefinitely) by using maintenance rehearsal. Long-Term Memory • The final stop for memory storage is our longterm memory, an unlimited capacity storage that can hold information over long periods of time. • Consolidation occurs when unstable, new memories are converted to stable, long-term memories. • Memories can endure indefinitely, especially when we make an effort to strengthen new memories. • We can make memories more durable through repeated practice, such as continuing to practice speaking a foreign language to keep that information. • Information can be organized in semantic networks. Semantic networks consist of nodes representing concepts, joined together by pathways that link related concepts. • For example, the phrase “fire engine” may be organized in a network of similarly related words, such as truck, fire, and red. In this network, words closer to one another are more strongly related. • When one “node” in the network is activated, others that are nearby also light up. This causes ones near them to turn on in a ripple effect called spreading activation. Street Vehicle Car Bus Truck Ambulance House Fire Engine Fire Orange Yellow Red Green Apples Violets Cherries Roses Flowers Pears Sunsets Sunrises Clouds Types of Long-Term Memory • Declarative memory handles factual information and information that requires a deliberate effort to recall. • Nondeclarative memory (called procedural memory) houses memory for actions (memory of “how”), conditioned responses, and emotional experiences. • LTM relies on semantic coding. Elaborative rehearsal (focusing on the meaning of the information and forming relevant connections/associations) helps strengthen long-term memory. Memory Declarative Memory (Factual Information) Procedural Memory (Actions, Perceptual Motor Skills, Conditioned Responses, Emotional Memories) Example: Riding a bike Handle Bars Pedals Spokes • If you know that a bike has two wheels, pedals, handlebars, etc., you are using declarative memory. If you know how to ride a bike, you are using procedural memory. Declarative memory is divided into episodic and semantic memory: Episodic memory is chronological (dated), recollections of personal experiences. Episodic memory includes all memories in which a “time stamp” is made. Semantic memory is general knowledge that is not tied to the time when it was learned. For example, that January 1st marks the new year, that dogs have four legs, etc., are examples of information related to semantic memory. • An analogy is to think of both as books. Episodic memory is an autobiography whereas semantic memory is an encyclopedia. Retrospective Memory Prospective Memory Past Future The Present Prospective memory involves remembering to perform actions in the future. Remembering to walk the dog or to take your medication involves prospective memory. Retrospective memory involves remembering events from the past or previously learned information. In retrospective memory you may try to remember who won the Super Bowl last year or what last week’s lecture covered. Procedural memory • Procedural memory involves remembering how to do things, or “procedures” for specific actions. Riding a bicycle, playing an instrument, or solving a mathematical equation would be examples of procedural memory. • Procedural memories are sometimes thought of as “implicit” memories, because they take very little or no conscious effort to retrieve. When you walk up a flight of stairs or ride a bicycle, are you ‘actively’ thinking of how to carry out those acts, or do they sort of happen on their own with very little conscious attention? Reconstructing Memories • When we retrieve information, it’s never an exact replay of the past. According to constructionist theory, memories are not replicas of past experiences. Instead, we reconstruct the past, and that can be distorted and include inaccurate information. • Our poor abilities to retrieve information accurately has been extensively studied, the misinformation effect, occurs when an individual’s recall of an event is altered by misleading post-event information. • Other research has consistently found that people introduce inaccuracies in the simple story-telling we do every day. These findings have helped psychologists understand that memory is not a perfect process and that its more malleable than once thought. Misinformation Effect • Elizabeth Loftus had people view a film of a car accident that occurred at an intersection with a stop sign. Some people were then given misleading information telling them that the traffic sign was a yield sign. • Participants who were not given the false information were much more likely to recall the correct traffic sign. Eyewitness testimony can be flawed and mistaken because of misinformation effects and other factors affecting reliability of long-term memory. Some of the factors affecting accuracy of eyewitness testimony: Ease of recall Degree of confidence General knowledge Types of questions Facial characteristics Flashbulb Memories Enduring memories of emotionally charged events that seem permanently burned into the brain. They are not necessarily more accurate than other memories. Some flashbulbs are very accurate over time, while others are subject to distortion (misinformation effect). Repressed Memories Skeptics of Repressed Supporters of Repressed Memory Memory Theory Theory • Abuse Do notisthink moreindividuals common than are lying we think on purpose • Therapists Repressionmay is a natural ask leading response questions to trauma until creates a false memory • the Lab patient researchinadvertently on implanting memories cannot be compared to • emotional Countless studies show that itabuse is easy to create events like sexual memories • false No direct and empirical evidence • Some court cases discredit existence of repressed memories • Misinformation effect and other research shows that memory is not as reliable as many of us think • Many psychologists, are skeptical of recovered memories of abuse; they do not imply that people reporting these memories are lying or have bad intentions. • Instead, they point to findings on the misinformation effect, suggestibility, and leading questions as contributors to the “uncovering” or repressed memories. Forgetting Decay Theory • Normally forgetting is a “bad thing,” is adaptive. • We do not have room to remembered everything. But even as an adaptive function, forgetting can be problematic, like when we forget a definition of a term for a test, or where our keys are, or worse. • Hermann Ebbinghaus had participants memorize nonsense syllables and tested their recall after various amounts of time had passed. He then plotted the amount of information (syllables) forgotten in the form of a forgetting curve. • He noticed that he forgot many of the syllables shortly after memorizing them. Though we now know that memorizing things with meaning are less forgettable than information with no meaning. Decay Theory • Decay theory is the belief that memories gradually fade and deteriorate over time. • One limitation of the theory is that it fails to account for unevenness in memory decay. Some memories fade quickly whereas others last a lifetime. • Massed versus spaced practice effect – cramming simply does not work as well as regular exposure to information repeatedly, over time. Interference Theory • Interference theory proposes that people forget information because of competition from other material. This can account for some of our forgetting. • Interference in which new information impairs previously learned information is called retroactive interference. • Proactive interference is the opposite, when old information interferes with new information. • Serial position effect: tendency to recall first and last items in a list better than items in the middle. • Called Primacy or recency effect • To minimize interference effects: Sleep on it, rehearse fresh memories, practice overlearning, give yourself a break between study periods, and avoid sequential study of similar material. Old Info New Info Retrieval Theory • Forgetting is the result of a failure to access stored memories Several ways the retrieval process breaks down: • Encoding failure • Lack of retrieval cues • Tip-of-the-tongue phenomenon Which is the correct image of a penny? This demonstrates encoding failure, due to a failure to bring this information into memory in the first place due to lack of attention. We only encode that which is important to know. We can identify a penny without needing to know the particular features of the image. We all have handled 1000s of pennies, yet most people cannot identify the correct one. This is due to a lack of encoding or ineffective coding – types of encoding failure. Motivated Forgetting Repression • Defense mechanism involving motivated forgetting of anxiety-evoking material • Can it be adaptive – even psychologically healthy – to forget certain things? • Freud offered a new explanation for retrieval failures – that we keep distressing impulses and disturbing memories buried in the unconscious through the process of repression. • This theory of forgetting is controversial in present-day psychology, due to a recent surge in lawsuits in which a potential victim claimed that childhood memories of abuse suddenly surfaced, usually in psychotherapy. Measuring Forgetting Measures of Retention: • How we measure memory has an important bearing on retention. • A recall measure, which requires a person to reproduce information on their own without any cues. If asked to memorize 10 words then say them out loud, this would be a recall test. • A recognition measure, which requires a person to select previously learned information from an array of options. All students take part in this process when completing multiple-choice or true-false questions on exams. Amnesia • After serious trauma, some develop amnesia (extensive memory loss). Similar to how interference is categorized, amnesia can be either retrograde or anterograde. • Retrograde amnesia results in loss of memories for events that occurred before the injury. • Anterograde amnesia results in loss of memories for events that occur after the injury. • By examining the brain structures and functioning of individuals with serious brain injury, scientists have identified some areas that may be important in the consolidation of memories, such as the hippocampus. Amnesia can also be caused by a psychological trauma, resulting in dissociative amnesia. The Biology of Memory • The engram, named by Karl Lashley, is a theoretical space in the brain where (Lashley believed) memories are stored. • Lashley spent years searching for the engram, and eventually concluded that it does not exist, and that memories are not stored in a singular brain structure. • Today experts believe that memories are stored in memory circuits in the brain that consist of complicated networks of nerve cells called neuronal networks. Anatomy of Memory • The hippocampus is essential to the formation of new memories of facts, general information, and life experiences. • Damage to the thalamus can result in amnesia. • The amygdala is involved in encoding emotional experiences, such as fear and anger, each of which have a memory component to them. Long-Term Potentiation • Kandel’s work with large sea snails showed that memory formation involves biochemical changes at the synaptic level. • Long-term memory may depend on a process called long-term potentiation, which is a long-lasting increase in neural excitability at synapses along a specific neural pathway. • Synaptic connections strengthened by repeated stimulation. So repeated presentation of the same information may strengthen these neural connections, resulting in better retention. Long-Term Potentiation Genetics & Memory • Gene regulation • Proteins necessary for making long-term memories • Work on genetic and memory may lead to treatments for Alzheimer’s and other memory disorders Any Questions?