MEMORY STORAGE. There are three major kinds of storage:

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1 MEMORY Jill Price was capable of remembering everything that happened last year and several years ago. Memory is the ability to store and retrieve information over time. Memories are the residue of those events, the enduring changes that experience makes in our brains and leaves behind when it passes. The three main functions of the memory: encoding, the process by which we transform what we perceive, think, or feel into an enduring memory; storage, the process of maintaining information in memory over time; and retrieval, the process of bringing to mind information that has been previously encoded and stored. ENCODING Memories are made by combining information we already have in our brains with new information that come in through our senses. Memory is influenced by the type of encoding we perform regardless of whether we consciously intend to remember an event or a fact. Three types of encoding processes are: 1) Elaborative encoding - the process of actively relating new information to knowledge that is already in memory. Elaborative encoding enhances subsequent retention. Thinking about a word s meaning (semantic judgment) results in deeper processing-and better memory for the word later-than merely attending to its sound (rhyme judgment) or shape (visual judgment). This helps remembering things in the long run fmri studies reveal that different parts of the brain are active during different types of judgments: (a) During semantic judgments, the lower left frontal lobe is active; (b) during organizational judgments, the upper left frontal lobe is active; and (c) during visual judgments, the occipital lobe is active. 2) Visual Imagery Encoding - the process of storing new information by converting it into mental pictures. Visual imagery encoding can substantially improve memory. Why does visual imagery encoding work so well? First, visual imagery encoding relates incoming information to knowledge already in memory. Second, when you use visual imagery to encode words and other verbal information, you end up with two different mental placeholders for the items a visual one and a verbal one which gives you more ways to remember them than just a verbal placeholder alone. This encoding activates visual processing regions in the occipital lobe. 3) Organizational Encoding - the process of categorizing information according to the relationships among a series of items. Waitresses use this type of encoding when they take orders instead of writing them down. In their head, they begin to group the orders into a sequence that matches the layout of the kitchen. Organizational encoding activates the upper surface of the left frontal lobe. Memory mechanisms that help us to survive and reproduce should be preserved by natural selection, and our memory systems should be built in a way that allows us to remember especially well encoded information that is relevant to our survival. Three different encoding tasks were used to test the idea: (1) Survival encoding when you have rank certain words that will help you to survive; (2) Moving encoding when you have to move to a different place and rank the words that will be most useful to you; (3) Pleasantness encoding when you have the rank the words based on their pleasantness. Survival encoding helps you to remember more words because it draws on elements of elaborative, imagery, and organizational encoding and we also tend to remember things that are linked to our survival. There are three major kinds of storage: STORAGE 1) Sensory memory - holds sensory information for a few seconds or less. Because we have more than one sense, we have more than one kind of sensory memory. Iconic memory is a fast-decaying store of visual information (decay in about a second). Echoic memory is a fast-decaying store of auditory information (decay in about 5 seconds). The hallmark of both the iconic and echoic memory stores is that they hold information for a very short time.

2 2) Short term memory - holds non-sensory information for more than a few seconds but less than a minute. Information can be held in this storage for about secs. Rehearsal is the process of keeping information in short-term memory by mentally repeating it. This memory is limited in how long and how much it can hold information. This memory can hold about seven meaningful items at once. One way to increase storage is to group several letters into a single meaningful item. Chunking involves combining small pieces of information into larger clusters or chunks. Working memory refers to active maintenance of information in short-term storage. Working memory includes subsystems that store and manipulate visual images or verbal information, as well as a central executive that coordinates the subsystems. This memory helps to remember the arrangement of pieces on a chessboard. Damage to the working memory will make it hard for people to remember a few letters/words and affect learning language. Working memory depends on regions within the frontal lobe. 3) Long term memory - holds information for hours, days, weeks, or years. In contrast to both sensory and shortterm memory, long-term memory has no known capacity limits. The hippocampal region of the brain is critical for putting new information into the long-term store. When this region is damaged, patients suffer from a condition known as anterograde amnesia, which is the inability to transfer new information from the short-term store into the long-term store. Some amnesic patients also suffer from retrograde amnesia, which is the inability to retrieve information that was acquired before a particular date, usually the date of an injury or operation. The idea that the hippocampus becomes less important over time for maintaining memories is related to the concept of consolidation, a process by which memories become stable in the brain. One type of consolidation operates over seconds or minutes. Eg: when someone meets an accident and cannot recall what happened right before the accident. The head injury probably prevented consolidation of short-term memory into long-term memory. Another type of consolidation occurs over much longer periods of time. These people can recall information from when they were kids but not of recent years. How does a memory become consolidated? The act of recalling a memory, thinking about it, and talking about it with others probably contributes to consolidation. Sleep contributes to memory consolidation by (1) increasing hippocampal involvement in recall a couple of days later and (2) facilitating interaction of the hippocampus with the frontal lobe, such that the hippocampus is later less centrally involved in recall. Reconsolidation is when memories can again become vulnerable to interference when they are recalled, thus requiring them to be consolidated again. Memories are not given permanent occupancy. Memories, Neurons & Synapses Memories are stored in the synapse - the small space between the axon of one neuron and the dendrite of another, and neurons communicate by sending neurotransmitters across these synapses. Sending neurotransmitters across a synapse strengthens the connection between the neurons. The story of Aplysia and memory is closely linked with the work of neuroscientist Eric Kandel. Aplysia has a simple nervous system with 20,000 neurons. Memory storage depends on changes in synapses, and LTP increases synaptic connections. Long-term potentiation, more commonly known as LTP, which is a process whereby communication across the synapse between neurons strengthens the connection, making further communication easier. Long-term potentiation has a number of properties that indicate to researchers that it plays an important role in long-term memory storage: It occurs in several pathways within the hippocampus; it can be induced rapidly; and it can last for a long time.

3 How does LTP take place? The NMDA receptor influences the flow of information between neurons by controlling the initiation of LTP in most hippocampal pathways. The presynaptic neuron releases the neurotransmitter glutamate into the synapse. Glutamate then binds to the NMDA receptor sites on the postsynaptic neuron. At about the same time, excitation in the postsynaptic neuron takes place. The combined effect of these two processes initiates long-term potentiation and the formation of long-term memories. (see img pg 232) RETRIEVAL The information outside your head is called a retrieval cue, which is external information that is associated with stored information and helps bring it to mind. Hints is an example of a retrieval cue like when you said you know who starred in pirates of the Caribbean and you remembered it when someone gave u a hint. Other examples of retrieval cue: Encoding specificity principle states that a retrieval cue can serve as an effective reminder when it helps recreate the specific way in which information was initially encoded. External contexts often make powerful retrieval cues. Eg: Recovering alcoholics often experience a renewed urge to drink when visiting places in which they once drank because these places serve as retrieval cues State-dependent retrieval is the tendency for information to be better recalled when the person is in the same state during encoding and retrieval. Eg: retrieving information when you are in a sad or happy mood increases the likelihood that you will retrieve sad or happy episodes. Retrieval cues can even be thoughts themselves, as when one thought calls to mind another, related thought Transfer-appropriate processing states that memory is likely to transfer from one situation to another when the encoding context of the situations match. Eg: if you were asked to think of a word that matches with brain and tom was asked to think of the meaning of brain. The next day, when we ask what matches with train, we will get the answer correct and Tom won t. Consequences of retrieval Retrieval Can Improve Subsequent Memory: the act of retrieval can strengthen a retrieved memory, making it easier to remember that information at a later time. Retrieval Can Impair Subsequent Memory: Retrieval-induced forgetting is a process by which retrieving an item from long-term memory impairs subsequent recall of related items. Eg: retrieval-induced forgetting can affect eyewitness memory. When witnesses to a staged crime are questioned about some details of the crime scene, their ability to later recall related details that they were not asked about is impaired compared with witnesses who were not questioned at all initially Process of Retrieval Trying to recall an incident & successfully recalling one are different processes occurred in different parts of the brain. When people try to recall an incident, the left frontal lobe is working. When successfully recall, the hippocampus is working. Further, successful recall also activates parts of the brain that play a role in processing the sensory features of an experience. For eg, recall of sounds activate the auditory cortex whereas recall of pictures activate the visual cortex. Explicit and Implicit memory forms of long term memory Explicit memory occurs when people consciously or intentionally retrieve past experiences. Eg: recalling last summer vacation. Implicit memory occurs when past experiences influence later behavior and performance, even though people are not trying to recollect them and are not aware that they are remembering them. Eg: when Greg was sad about his dads death but he had no conscious knowledge of the event.

4 A type of implicit memory is procedural memory, which refers to the gradual acquisition of skills as a result of practice, or knowing how to do things. Eg: riding a bike. Another type of implicit memory is priming, an enhanced ability to think of a stimulus, such as a word or object, as a result of a recent exposure to the stimulus. Eg: when you are given a list of words to study and then given fill in the blanks, you would get those words you studied correctly. Priming can persist over very long periods. Priming seems to make it easier for parts of the cortex that are involved in perceiving a word or object to identify the item after a recent exposure to it and therefore the brain saves processing time after priming. People with amnesia lack explicit memory. Semantic and Episodic memory Semantic memory is a network of associated facts and concepts that make up our general knowledge of the world, whereas episodic memory is the collection of past personal experiences that occurred at a particular time and place. Episodic memory is special because it is the only form of memory that allows us to engage in mental time travel, projecting ourselves into the past and revisiting events thus allowing us to connect our pasts and presents. This memory also helps us to envision the future and it is a very flexible system Hippocampus is not necessary for acquiring new semantic memories. Remembering the past and imagining the future depends on this network including the hippocampus & a part of the medial temporal lobe long. Unsure if animals can engage in mental time travel of episodic memory SEVEN SINS OF MEMORY 1) Transience: forgetting what occurs with the passage of time. Transience occurs during the storage phase of memory, after an experience has been encoded and before it is retrieved. The quality of our memory also declines. Retroactive interference, which occurs when later learning impairs memory for information acquired earlier. Eg: when Friday comes, you don t remember clearly what work you did on Monday. Proactive interference, in contrast, refers to situations in which earlier learning impairs memory for information acquired later. 2) Absentmindedness: a lapse in attention that results in memory failure. One common cause is lack of attention. Attention plays a vital role in encoding information into long-term memory. Without proper attention, material is much less likely to be stored properly and recalled later. Another common cause of absentmindedness is forgetting to remember what you have to do. This is called prospective memory, or remembering to do things in the future 3) Blocking: a failure to retrieve information that is available in memory even though you are trying to produce it. Eg: when something is at the tip of your tongue. When you re in a tip of the tongue state you often know something about the item that you can t recall such as the meaning of the word. Name blocking usually results from damage to parts of the left temporal lobe on the surface of the cortex, most often as a result of a stroke 4) Memory Misattribution: assigning a recollection or an idea to the wrong source. Memory misattribution errors are some of the primary causes of eyewitness misidentifications. Eg: when you watch a show with Tom and your house get burgled the description of the thief you give might be that of Tom instead of the burglar. You misattribute the memory of Tom s face to the burglar. Part of memory is knowing where our memories came from. This is known as source memory: recall of when, where, and how information was acquired. A present situation that is similar to a past experience may trigger a general sense of familiarity that is mistakenly attributed to having been in the exact situation previous. Such misattribution could be the cause of déjà vu experiences, where you suddenly feel that you have been in a situation before even though you can t recall any details. We may be even more prone to mistakes in remembering who we have told something before, a process called destination memory. People with damage to frontal lobes are prone to misattribution. False recognition, which is a feeling of familiarity about something that hasn t been encountered before. 5) Suggestibility: the tendency to incorporate misleading information from external sources into personal recollections. Eg: people were shown a videotape of a car at a stop sign. Those who later received a misleading suggestion that the car had stopped at a yield sign often claimed they had seen the car at a yield sign

5 6) Bias: the distorting influences of present knowledge, beliefs, and feelings on recollection of previous experiences. Sometimes what people remember from their pasts says less about what actually happened than about what they think, feel, or believe now. Consistency bias is the bias to reconstruct the past to fit the present. Change bias is the tendency to exaggerate differences between what we feel or believe now and what we felt or believed in the past. Egocentric bias, the tendency to exaggerate the change between present and past in order to make ourselves look good in retrospect. Eg: blood donors sometimes recall being more nervous about giving blood than they actually were. Change biases color memory and make people feel that they behaved more bravely or courageously than they actually did. 7) Persistence: the intrusive recollection of events that we wish we could forget. Persistence frequently occurs after disturbing or traumatic incidents. Emotional experiences tend to be better remembered than nonemotional ones. Flashbulb memories, which are detailed recollections of when and where we heard about shocking events Eg: everyone can recall where and how they heard about 9/11. A key player in the brain s response to emotional events is a small, almond-shaped structure called the amygdala. The amygdala, located next to the hippocampus, responds strongly to emotional events. Patients with amygdala damage are unable to remember emotional events any better than non-emotional ones