Chapter 6: Memory Flashcards
Memory
ability to store and retrieve information over time
3 key functions of memory
encoding, storage, and retrieval
Encoding
process of transforming what we perceive, think, or feel into an enduring memory
Storage
process of maintaining information in memory over time
Retrieval
process of bringing to mind information that has been previously encoded and stored
How do we make memories?
by combining information we already have in our brains with new information that comes in through our senses
3 types of encoding
semantic, visual imagery, and organizational
Semantic encoding
process of relating new information in a meaningful way to knowledge that is already stored in memory, enhances long-term retention
Brain areas activated by semantic encoding
lower left part of the frontal lobe and inner part of the left temporal lobe; more activity=more likely that the person will remember
Visual imagery encoding
process of storing new information by converting it into mental pictures: relates incoming information to knowledge already in your memory and uses two mental placeholders (visual and verbal)
Brain area activated by visual imagery encoding
visual processing areas in the occipital lobe
Organizational encoding
process of categorizing information according to the relationships among a series of items e.g. in a hierarchy and event segmentation
Brain area activated by organizational encoding
upper surface of the left frontal lobe
Survival encoding
Memory mechanisms that help us survive and reproduce (survival-related information) are preserved by natural selection; draws on all 3 types of encoding, goals, and planning
3 major kinds of memory storage
sensory, short-term, and long-term
Sensory memory
type of storage that holds sensory information for a 1 second or less, decays very quickly and no capacity limit
Types of sensory memory
iconic and echoic
Iconic memory
fast-decaying store of visual information, usually decay in about 1 second or less
Echoic memory
fast-decaying store of auditory information, usually decay in about 5 seconds
Short-term memory
storage that holds non-sensory information for more than a few seconds but less than a minute by paying attention to it, can hold up to 7 items
Rehearsal
process of keeping information in short-term memory by mentally repeating it
Serial position effect
the first few and last few items in a series are more likely to be recalled than the items in the middle
Primacy effect
enhanced recall of the first few items because they receive more rehearsals, thus more likely to be encoded into long-term storage
Recency effect
enhanced recall of the last few items, result from rehearsing items that are still in short-term storage
How is short-term memory limited?
Limited in how long it can hold information and how much information it can hold (about seven meaningful items at once)
Chunking
combining small pieces of information into larger clusters or chunks that are more easily held in short-term memory
Working memory
STM storage that actively maintains and manipulates information, can store up to 4 items (without verbal rehearsal)
2 subsystems of working memory that store and manipulate
Visuo-spatial sketchpad (for visual images) and phonological loop (for verbal information like remembering letters)
Episodic buffer in working memory
integrates visual and verbal information from the subsystems into a multidimensional code (not sensory-specific anymore), a gateway to long-term memory
Central executive in working memory
coordinates the subsystems and the episodic buffer, depends on regions within the frontal lobe
Long-term memory
type of storage that holds information for hours, days, weeks, or years, has no known capacity limits
Part of the brain that acts as an index, critical in making new memories
hippocampus- links together separate elements (initially encoded by distinct regions in the cortex) to remember them as one memory, may become less important as the memory ages, and less involved in less detailed memories
Anterograde amnesia
inability to transfer new information from the short-term into the long-term store e.g. patient HM
Retrograde amnesia
inability to retrieve information that was acquired before a particular date, usually the date of an injury or surgery
Consolidation
process by which memories become stable in the brain, boosted by sleep
Reconsolidation
consolidated memories can become vulnerable to disruption when they are actively recalled, thus requiring them to be consolidated again; process of replacing or modifying a stored memory with a new version
Disrupting reconsolidation
eliminates a fear memory in the amygdala
Long-term potentiation (LTP)
process whereby communication across the synapse between neurons, specifically in the hippocampus, strengthens the connection, making further communication easier
Properties of LTP that indicate its important role in long-term memory storage
occurs in several pathways within the hippocampus, can be induced rapidly, can last for a long time
Retrieval cue
external information that is associated with stored information and helps bring it (inaccessible information) to mind
Encoding specificity principle
a retrieval cue can serve as an effective reminder when it helps re-create the specific way in which information was initially encoded
State-dependent retrieval (inner state retrieval cues)
process whereby information tends to be better recalled when the person is in the same state during encoding and retrieval
Transfer-appropriate processing
the idea that memory is likely to transfer from one situation to another when the encoding and retrieval contexts of the situations match
Retrieval-induced forgetting
a process by which retrieving a target item from long-term memory impairs subsequent recall of related items by suppressing (frontal lobe) those unwanted competitors
Brain regions activated when people TRY to retrieve information
regions in the left frontal lobe, reflects the mental effort
Brain region activated when SUCCESSFULLY remembering a past experience
hippocampal region and parts of the brain that play a role in processing the sensory features of an experience e.g. auditory cortex (upper part of temporal lobe) and visual cortex (occipital)
Explicit memory
occurs when people consciously or intentionally retrieve past experiences, tends to fade in the absence of recall, declines with age, varies across individuals
Implicit memory
occurs when past experiences influence later behavior and performance, even without an effort to remember them or an awareness of the recollection, preserved in healthy aging, less individual difference
Procedural memory
kind of implicit memory that refers to the gradual acquisition of skills as a result of practice or “knowing how” to do things, unconscious and automatic, often difficult to explain verbally, does not rely on hippocampus but cerebellum and limbic system
Priming
kind of implicit memory that results in an enhanced ability to think of a stimulus as a result of a recent exposure to that stimulus without awareness of the connection, can persist over long periods of time, reduced activity in cortex regions activated during unprimed tasks, saves processing time and effort (top-down processing)
Perceptual priming
reflects implicit memory for the sensory features of an item, depends more on regions toward the back of the brain and the right hemisphere e.g. goat and boat (rhyming)
Conceptual priming
reflects implicit memory for the meaning of a word or how you would use an object, depends more on regions toward the front of the brain and the left hemisphere e.g. seat and chair
Semantic memory
explicit memory for meaning; a network of associated facts and concepts that make up our general knowledge of the world, hippocampus is not necessary, similar across individuals
Episodic memory
explicit memory for specific events in context; collection of past personal experiences that occurred at a particular time and place, relied on to envision our personal futures, activates a brain network including the hippocampus and medial temporal lobe, varies across individuals
Transience
forgetting what occurs with the passage of time, occurs during the storage phase of memory after an experience has been encoded and before it is retrieved
The curve of forgetting - Hermann Ebbinghaus
Memories fade rapidly soon after the event occurs and slows down as more time passes, and also switches from specific to more general
Retroactive interference
situations in which later learning impairs memory for information acquired earlier
Proactive interference
situations in which earlier learning impairs memory for information acquired later
Childhood amnesia or infantile amnesia
most of us have few or no memories from the first few years of life, may be impacted by culture
Absentmindedness
a lapse in attention that results in memory failure when attention is divided or distracted (information doesn’t disappear from memory)
What happens when attention is divided?
lower left frontal lobe is prevented from performing its role in semantic encoding and less hippocampal involvement for episodic memory, leading to absentmindedness
Prospective memory
remembering to do things in the future, failure of such leads to absentmindedness
Blocking
tip-of-the-tongue experience, a failure to retrieve information that is available in memory even though you are trying to produce it, occurs more as we age and especially for names of people and places
Memory misattribution
assigning a recollection or an idea to the wrong source, primary cause of eyewitness misidentifications
Source memory
recall of when, where, and how information was acquired
False recognition
a feeling of familiarity about something that hasn’t been encountered before from a miscombination between source memory and episodic memory, also primary cause of eyewitness misidentification e.g. déjà vu
Suggestibility
tendency to incorporate misleading information from external sources into personal recollections due to not storing details and social pressure
Bias
the distorting influences of present knowledge, beliefs, and feelings on recollection of previous experiences
Consistency bias
bias to reconstruct the past to fit the present, exaggerates the similarity between past and present
Change bias
tendency to exaggerate differences between what we feel or believe now and in the past
Egocentric bias
tendency to exaggerate change between present and past to make ourselves look good in retrospect
Persistence
intrusive recollection of events that we wish we could forget, often occurs after disturbing or traumatic incidents, consequences of emotional experiences, involves amygdala
Flashbulb memories
detailed recollections of when and where we heard about shocking and emotional events, not always accurate
Are the seven “sins” vices or virtues?
No, they are the price we pay for the benefits that memory provides
What are the seven “sins” (memory failures)?
Transience, absentmindedness, blocking, memory misattribution, suggestibility, bias, persistence
Benefit from transcience
an adaptive property of memory, helps you forget unimportant information and enhances our ability to make decisions based on memory
Benefits from absentmindedness and blocking
side effects of selectivity of memory, preserving details worthy of attention and recall
Benefits from memory misattribution and suggestibility
flexibility of memory, allowing us to recombine elements of past experiences in new ways
Benefits from bias
contributes to our overall sense of contentment
Benefits from persistence
makes us adaptive, able to remember threatening and traumatic events as they could pose a threat to survival
Long-term benefits of retrieval
retrieval can improve subsequent memories, especially LTM e.g. studying (encoding) and testing (retrieval)
How can retrieval change memory?
During reactivation or retrieval, new information can be incorporated into your memory that is reconsolidated into one that is totally different from the original memory
Factors that affect eyewitness memory
Encoding stage factors: stress, violence, emotion, arousal; Storage stage factors: time, Retrieval stage factors: expectations and reconsolidation
