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I. Attention and Memory H.M. (Henry Molaison) suffered from severe epilepsy. Originated in the temporal lobes > surgery, lost the ability to form new long term memory-world stopped Sept 1953 “Every day is alone in itself” Memory: the nervous system’s capacity to acquire and retain useable skills and knowledge, allowing organisms to benefit from experience, often incomplete biased, distorted A. How Does Attention Determine What is Remembered Look, listen = commands that direct attention attention is limited, when divided among too many tasks, performance suffers multitasking’ 1. Visual Attention Is Selective and Serial Anne Treisman: we automatically identify “primitive” features, such as color, shape, orientation, and movement, within an environment Tresiman has proposed that separate systems analyze objects’ different visual features Parallel processing: these systems all process information at the same time, and we can attend selectively to only feature by effectively blocking the further processing of the others; visual search tasks (feature search tasks)participants look at a display of different objects on a computer screen, searching for the ones, called targets, that differ from the others in only one feature, other objects in the display = distractions Color, motion, orientation, and size features that pop out despite # of distracters Searching for two features is serial (need to look at stimuli one at a time), and effortful (takes longer and requires more attention) Conjunction task: ex-trying to find all the red X’s in a display of differently colored Xs and Ys, stimulus looking for is made up of two different features 2. Auditory Attention Allows Selective Listening Hard to perform two tasks the same time, esp if uses same mechanisms E.C. Cherry-(selective listening) cocktail party phenomenon: focus on a single conversation in the midst of a chaotic cocktail party, yet a particular stimulus can capture your attention Proximity and loudness influence what you will attend to, your selective attention can also determine which conversation you hear Personally relevant information often gets through attention filter 3. Selective Attention Can Operate At Multiple Stages of Processing Donald Broadbent: the filter theory-people have a limited capacity for sensory information and thus screen incoming information ,letting in only the most important information and closes for irrelevant information Some stimuli demands attention, ex: cramps, higher pitched sounds like crying baby Decisions about what to attend are made early in the perceptual process, but studies also reveal that unattended information is processed to some extent Change blindness: often “blind” to large changes in our environments because we cannot attend to everything in the vast array of visual information available (ex: giving directions to stranger, then momentarily blocked, 50% of participants didn’t notice if talking to different person if same race and sex) Large discrepancy between what people believe they see and what they actually see, change blindness shows how attention influences memory B. What Are the Basic Stages of Memory Information processing model: Memory’s multiple processes can be thought of as operating over time in three distinct phases (1) encoding phase: occurs at the same time as learning, as info is acquired. Encoded or changed into a neural code that the brain can use (on acquisition) (2) the storage phrase, which can last a fraction of a second or as long as a lifetime-at least three storage systems (3) retrieval Modal memory model: Sensory memory, short term/working memory and long term memory proposed by Richard Atkinson and Richard Shiffrin 1. Sensory Memory is Brief Sensory Memory: temporary memory system, lasting only a fraction of a second and closely tied to the sensory system-often unaware that it’s operating Sensory systems transduce or change that information into neural impulses and everything we remember is the result of neurons firing n the brain George Sperling provided initial empirical support for sensory memory: three rows of letters flashed on a screen for 1/20 of a second-part. Asked to recall all the letters Concludes that visual memory only persists for ½ of second after which the sensory memory trace faded progressively until it was no longer accessible See the world continuously rather than in jerky bits b/c of visual memory, keeps info just long enough for you to connect one image with the next 2. Working Memory is Active Information attended to is passed from sensory stores to STM: a limited capacity memory system that holds information in awareness for a brief period This short term system often referred to as working memory (WM) to indicate that it is a memory (storage) system that combines information from difference sources and can work on the information we have in memory Also called immediate memory Info remains in the working memory for about 20-30s then disappears unless you actively prevent that from happening by thinking about or rehearsing the information a) Memory Span and Chunking Memory span: amount of information WM can hold, George Miller estimates 7 Chunking: organizing information into meaningful units to make it easier to remember b) Working Memory’s Four Parts WM is an active processing unit that deals with multiple types of information, such as sounds, images, and ideas Aland Baddeley and his colleagues developed an influential model of an active memory that they called the working memory-3 components are the central executive, the phonological loop, the visuospatial sketchpad, and the episodic buffer Central executive: presides over interactions among the phonological loop, v. sketchpad, e. buffer, and ltm. Encodes information form the sensory systems, then fulterns information that is sufficiently important to be stores in the long term memory, also retrieves info from the ltm Phonological loop: encodes auditory information and is active whenevery a person tries to remember works by reading them, speaking them, or repeating them“inner voice,” words processed by ho they sound rather than how they look or mean Visiospatial sketchpad: processes visual information, objects’ features and location Study the visiospatial and phonological loop through brain damage Episodic buffer: recently added, holds temporary information about oneself, deawing heavily on long term episodic memory C. Long Term Memory Is Rel. Permanent -Long Term Mry (LTM)-rel permanent storage of information 1) Distinguishing LTM from Working Memory LTM distinct from working memory in two different ways: duration and capacity Serial position effect: the ability to recall different items from a list depends on order of presentation, with items presented early or late in the list remembered better than those in the middle Primacy effect: better memory people have for items presented at the begging of the list Recency effect: better mem. For most recent Items at end of list Rehearse the earliest items the most, last few items by contrast are still in WM Biological level of analysis: H.M. WM is working normal to keep track of conversation, his LTM is intact but unable to transfer new information from WM to LTM. Two memory systems are highly indertependent 2) What Gets Into LTM Information enters permanent storage through rehearsal Overlearning: keep rehearsing material leads to improved memory, esp over long periods of time therefore distributed practice-is remembered better than massed practice (cramming) We attend just enough for the task at hand and lose information that seems irrelevant Only information that helps us adapt to the environment is typically transformed into LTM II. What Are the Different LTM Systems Older view: memories differed in terms of strength, and their accessibility , but generally all memories were considered to be of the same type Late 1970s and early 1980s, Endel Tulving, Daniel Schacter, Larry Squire challenged this-memory is not just one entity but rather a process that involves several interacting systems The systems share a common function, they encode and store different types of information in different ways A. Explicit Memory Involves Conscious Effort The most basic distinction between memory systems is the division of memories we are consciously aware of from memories we acquire without conscious effort or intention and do not know we know Implicit memory: unconscious memory Explicit memory: process we use to remember info we can say we know Declarative memory: cognitive info retrieved in explicit memory Endel Tulving found that explicit memory can be divided into episodic and semantic memory Episodic memory: person’s past experiences and includes information about the time an dplace the experiences occurred Semantic memory: knowledge of facts independent of personal experience B. Implicit Memory Occurs Without Deliberate Effort Implicit memory consists of memories without awareness of them, not able to put the memories into words Classical Conditioning employs implicit memory Attitudes are influenced by implicit learning Advertisers rely on implicit memory to influence our purchasing decisions Often unaware of influences on how we think or feel At the social level of analysis, implicit attitude formation can affect our beliefs about people (ex: false fame) Implicit memory involved in repetition priming, improvement in identifying or processing a stimulus that has been experienced previously Procedural memory/motor memory: involves motor skills, habits, and other behaviors employed to achieve foals such as coordinating muscle movements to ride a bicycle or following the rules of the road while driving C. Prospective Memory Is Remembering to Do Something Prospective memory: future orientated Individual remembers to do something at some future time The cognitive effort involved in attending to certain information makes us unable to attend closely to other information Prospective memory involves both automatic and controlled processes III. How Is Information Organized In Long Term Memory A. Long Term Storage Based on Meaning memory is a process of storing new information so that the information is available when the remember needs it. Perceptual experiences were transformed into representations, or codes, which are then stored ex: the concept of dog is a mental representation for the category animals that share a certain features such as barking and fur retrieval often involves an explicit effort to access the contents of memory storage, sometimes retrieve information without any effort (implicit) memories are stored by meaning levels of processing model: Craik and Lockhort, the more deeply an item is encoded the more meaning it has the better it is remembered. Different types of rehearsal leads to different encoding Maintenance rehearsal is repeating the item over and over Elaborative rehearsal encodes the information in a meaningful ways-link it to knowledge from LTM Brain imaging studies-semantic encoding activates more brain regions than shallow encoding-better brain activity is associated with better memory B. Schemas Provide an Organizational Framework Schemas: structures and long-term memory to help us perceive, organize, process, and use information. Schemas help us sort out incoming information, and guide our attention to environments relevant features Thanks to schema we construct new memories by filling in holes within existing memories, overlooking inconsistent information, and interpreting meaning based on past experiences Schemas can lead to biased encoding, culture influences schemas C. Information is Stored in Association Networks networks of associations, knowledge of the world is organize the things related to meeting are linked in storage. An item's distinctive features are linked, so that is asked to identify the item. Each unit of information in the network is in node, node is connected to many other nodes. An important feature of network models for activating one increases the likelihood that closely associated node, the stronger the association between them and therefore the more likely activating one will activate the others spreading activation models of memory, if the idea for activating one node increases the likelihood of associated nodes becoming active stimuli in working memory activates specific nodes in long-term memory. In this activation increases the ease of access that material, thereby facilitating retrieval D. Retrieval Cues Provide Access to LTS a retrieval cue: anything that helps a person sort through the ast data in long term memory to access the right information explains why it is easier to recognize than to recall information 1) Encoding Specificity Endel Tulving’s encoding specificity principle, any stimulus encoded along with an experience can later trigger a memory of the experience Memory enhancement, the recall sityation is similar to the encoding situation, is known as context depedent memory Physical location, odors, and background music Internal cues such as mood state or inebriation can facilitate the recovery of information from LTM Enhancement of memory when internal states match during encoding and recall is known as state dependent memory IV. What Brain Processes Are Involved in Memory? A. There Has Been Intensive Effort TO Identify Memory’s Physical Location Engram: physical site of memory storage Lashley found that the size of the area removed rather than its location was the most important in predicting retention Equipotentiality: Memory is distributed throughout the brain rather that confined to any specific location <emories are stored in multiple regions of the brain and linked through memory circuts, Donald Hebbs “wire together fire together” A great deal of neural specification occurs , such that different brain regions are responsible for storing different aspects of information Declarative memory and procedural memory use different brain regions Lashley’s failure to find critical brain regions for memorit us due to at least two factors Main task he used to study memory involved multiple sensory systems Lashley did not examine subcortical areas, which are now known to be important FOR MEMORY RETENTION Regions within temporal lobes are important for the ability to encode new memories The temporal lobes are important for declarative memory, less important for implicity memor Amygdale: fear learning B. The Medial Temporal Lobes Are Important for Consolidation of Declarative Memory Medial section of the temporal lobes important for declarative memory, includes amygdala and hippocampus Anterograde amnesia-inability to store new explicit memories (H.M) Damage to the medial temporal lobes interrupts storage of new material without impairing acess to old material Immediate memories become lasting memories through consolidation, all learning leaves a biologival trial in the rbain Results from changes in the strength of neural connections that support memoriy and from the construction of new synapses Medial temporal lobes are responsible for coordinating and strengthening the connections among neurons when something is learned but the actual storage most likely occurs in the particular brain regions engaged during the perception, processing, and analusos of the material being learned Visual information is stored in the cortical areas involved in visual perception, whereas sound is tored in the areas involved in auditory perception Memory for sensory experiences involves reactivating the cortical circuits involved in perceiving them Medial temporal lobes form links or poiners between the different storage sties and direct the gradual strengthening of the connections between these links Once memories are activated they ned to be consolidated afain to be stored back in memory (reconsolidation) The newly reconsolidated memories may differ from their original versions, memories change when we use them and are not accurate reproductions of what was experienced 1)Spatial Memory Hippocampus, spatial memory: memory for the physical environment (directions, locations of objects, and cognitive maps) Supported by place cells, neurons that, in lab test with rates, fire only when a rat returns to a specific location, such as one part of the maze When rat is placed in novel environment, none of the hippocampus place cells fire Place cells acquire links to the surrounding Sleep is important to consolidate memories C. The Frontal Lobes Are Involved in Many Aspects of Memory Frontal lobes are important to many aspects of memory, including episodic, working, and spatial memory, tim sequences, and various aspects of encoding and retrieval Extensive neural networks connect the prefrontal cortex with other brain regions such as the medial temporal areas Brain imaging studies have provided compelling evidence that the frontal lobes are crucial for encoding Deep encoding tasks will more likely lead to frontal activation than will shallow encoding tasks Remembered words are associated with stronger activation of the frontal lobes than are than are forgotten words Working memory holds information temporarily so that it can be used to solve provlems, understand conversations, and follow plans Patients with damage to the frontal areas often have difficulty following plans and goals, and monkeys given frontal lesions show impaired frontal memory Frotnal regions bcome active when info is being retrieved from ltm into wm or encoded form wn into ltm D. Neurochemistry Underlies Memory Mry involves alterations in connections across synapses, as memories are consolidated neurons like into distributed networks and those networks become linked Various of neurotransmitters can weaken or enhance memory Collectively know as memory modulatoirs because they modulate or modify memory storage 1) Neurochemistry Indicates the Meaningfulness of Stimuli Important events lead to neurochemical changes that produce emotional reactions Epinephrine is secrete not within the brain bit into the bloodstram from the adrenal glands, which are near the kidneys Glucose=memory enhancer 2) The Amygdala and the Neurochemistry of Emotion Arousing event causes greater activity of norepiniphrine receptors which strengthens the memory of that event The amygdale has norepiniphrine receptors and is involved in the memory of fearful events Emotional memory activates the right but not the left amygdale in men, and it activates left but not right amygdale in women Women have better emotional memory than men PTSD, hypervigilant to stimuli associated with their traumatic events V. When Do People Forget? Frgetting: the inability to retrieve memory from LTS Forgetting occurs rapidly over the first few days but then levels off “method of savings” examine how long it took people to relearn lists of nonsense syllables, difference between learning and relearning\ David Schacter the seven sins of memory: transience, absentmindedness, blocking, misattribution, suggestibility, bias, persistence 1) Transience Transience: the pattern of forgetting over time Most forgetting occurs because of interference from other information Proactive interference: old information inhinits the abilty to remember new information Retroactive information: new information inhibits the ability to remember old information 2) Blocking is Temporary Blocking: person temporarily unable to remember something Tip of the tongue phenomenon-Roger Brown and David McNeill Blocking often occurs because of interference from words that are similar in some way such as in sound or meaning, and that keep recurring 3) Absentmindedness Absentmindedness: inattentive or shllow encoding of events Change blindness Cultural variations in patterns of attention, and attributed these differences to early socialization practices 4) Amnesia is a Deficit in LTM Amnesia is a deficit in ltm, resulting from disease, brain injury, or psychological trauma Retrograde amnesia, people lose past memories for events, facts, people, or even personal information Anterograde amnesia: people lose ability to form new memories Many cases of amnesia results from damage to the medial temporal lobes, damage to other subcortical areas, such as a round the thalamus can also lead to amnesia Korsakoff’s syndrome VI. How Are Memories Distorted A. Flashbulb Memories Can Be Wrong Flashbulb memories refers to vivid memories for the circumstances in which one first learned of a surprising and consequential or emotionally arousing event 1) Do You Remember Where You Were When You Heard…? Researchers have to wait for a “flash” to go off and then immediately conduct their study Neisser and Harsch had 44 psych students fill ut a questionnaire the day the shuttle exploded, only three students had perfect recall 2) Stress and memory revisited Flashbulb exoeriences are recalled more accurately than inconsequential or unsurprising events Any event that produces a strong emotional response will likely produce a vivid, though not necessarily accurate, memory Von restorff effect: A distinctive event might simply be recalled more easily than trivial events, however inaccurate B. People Make Source Attributions Source misattribution: the misremembering of the time, place, person, or circumstances involved with a memory False fame effect: people mistakenly believe that someone is famous because they have encountered the person’s name before Sleeper effect: arguments that initially are not very persuasive because they come from questionable sources become more persuasive over time Cryptomnesia: when a person thinks he or she has come up with a new idea, but really has retrieved an old idea from memory and failed to attribute the idea to its proper source C. People are Bad Eyewitnesses Most powerful forms of evidence eyewitness account People are particularly bad at accurately identifying individuals of other ethnicites or races The greatest activiation of fusiform face area to same race races accounts for people’s superior memory for members of their own race Change blindness Suggestibility: the development of biased memories when people are provided with misleading information Loftus and Palmer-participants asked to watch a videotape of the same scene but with a yield rather than a stop sigh-smashed vs. contacted, hit, bumped, collided Eyewitnesses who report vivd details of all the scene’s aspects are probably less credible than those with poor memories for little details D. People Have False Memories Source amnesia: person has a memory for an event but cannot remember where he or she encountered the information The absence of early memories, childhood amnesia, may be due to the early lack of linguistic capacity as well as to immature frontal lobes List of associated words often produces false recollections extremely reliable Confabulation: the false recollection of episodic memory “honest lying” ex: Moskavitch, H.W. Capgras syndrome, often have damage to the frontal lobes and the limbic brain regions, brain region involved in emotion is separated from the visual imput so the images of family members is no longer associated with warm feelings E. Repressed Memories are Controversial False memories for traumatic events have been implanted by well meaning but misguided therapists F. People Reconstruct Events to Be Consistent Memory bias: people’s memories for events change over time to be consistent with current beliefs or attitudes People tend to recall their past attitudes ad past beliefs as being consistent with their current ones, often revising their memories when they change attitude G. Neuroscience May Make It Possible to Distinguish Between T/F Memories When we remember something, the brain areas activated are the same ones that were active when we first learned it, auditory memories activate auditory areas of the brain Retrieving a memory seems to require the same neural activity that was involved in the initial encoding\ False memories tend to be similar in many ways to true memories