Definitions Flashcards
memory
is the ability to store and retrieve info over time. the persistence of learning over time. not 100% stable, subject to disruption during reconsolidation. stored in networks of related info.
encoding
the process of transforming what we perceive, think, or feel into an enduring memory.
storage
the process of maintaining info in memory over time.
Retrieval
The process of bringing to mind info that has previously been encoded or stored. out of long term storage into working memory.
How memories are made
Made by combining info we already have in our brains with new info that comes in through our senses. Memories are constructed, not recorded.
Three types of encoding processes
Semantic encoding, visual imagery encoding, and organizational encoding.
Semantic judgements
Requires participants to think about the meaning of the words. Have much better memory of words than did those who thought about how the word looked or sounded.
Rhyme judgements
Requires the participants to think about the sound of the words.
Visual judgements
Requires the participants to think about the appearance of the words.
Semantic encoding
meaning; the process of relating new info in a meaningful way to knowledge that is already stored in the memory. Enhances long term retention. Uniquely associated with increased activity in the lower left part of the frontal lobe and the inner part of the left temporal lobe. More activity in these areas = the more likely the person will remember the info.
Visual imagery encoding
imagery; strengthens semantic encoding. visual memories endure longer. the process of storing new info by converting it into mental pictures. Can recall twice as many items as participants who just mentally repeated the words. When creating a visual image, you relate incoming info to knowledge already in memory. You have two mental placeholders when encoding words with images - a visual and a verbal one - which gives you more ways to remember them. Activates visual processing regions in the occipital lobe.
Organizational encoding
The process of categorizing info according to the relationships among a series of items. Activates the upper surface of the left frontal lobe. Different types of encoding strategies appear to rely on different areas of brain activation.
Survival and reproduction
Memory mechanisms that help us survive and reproduce should be preserved by natural selection, and our memory systems should be built in a way that allows us to remember well-encoded info that is relevant to our survival.
Survival encoding
Draws on elements of semantic, visual imagery, and organizational encoding. Encourages participants to engage in extensive planning.
Three kinds of memory storage
Sensory, short term, and long term.
Sensory memory
Type of storage that holds sensory info for a few seconds or less. limited sensory record.
Iconic memory
Fast decaying store of visual info. Decay in 1 second or less. (1/2 sec)
Echoic memory
Fast decaying store of auditory info. Decay in 5 seconds or less. (3-4 secs)
Short term memory
Holds non sensory info for more than a few seconds, but less than a minute. Usually about 15-20 seconds. About 7 items. active encoding.
Rehearsal
The process of keeping info in short term memory by mentally repeating it.
Chunking
Combing small pieces of info into larger clusters or chunks that are more easily held in short term memory. meaningful units.
Working memory
Active maintenance of info in short term storage. Consciously aware of info in working memory. New short term memories encoded from sensory memory: organized and rehearsed and may be encoded into long term memory. Recall long-term memories and utilize, modify, and integrate with new info. 7 +/- 2 pieces of info. ~20 seconds. Capacity extended by chunking and rehearsal. // Includes subsystems that store and manipulate visual images or verbal info, as well as a central executive that coordinates the subsystems. Central executive component depends on regions within the frontal lobe that are important for controlling and manipulating info on a wide range of cognitive tasks.
Long term memory
Type of storage that holds info for hours, days, weeks, or years. No known capacity limits. encoded and stored. based on improved communication in the neural network activated by the info being learned. formation relies on neural changes. does not create an exact replica of the info.
Anterograde amnesia
Happens when the hippocampal region is damaged; inability to transfer new info from the short term store into the long term store.
Retrograde amnesia
The inability to retrieve info that was acquired before a particular date, usually the date of an injury or surgery.
Storage of different aspects of a memory
Including sights, sounds, smells, emotional content - are stored in different places in the cortex
Hippocampal region
Acts as a kind of “index” that links together all of these separate bits and pieces so that we remember them as one memory. Over time, the index may become less necessary.
Consolidation
The process by which memories become stable in the brain. More resistant to disruption. One type occurs in seconds/minutes and another over days, weeks, months, and years. Second type likely involves transfer of info from the hippocampus (where early consolidation occurs and memories are fragile and easily lost + anterograde amnesia) to more permanent storage sites in the cortex (long term consolidation + retrograde amnesia). The act of recalling a memory, thinking about it, and talking about it probably contribute to consolidation. Sleep too.
Consolidated memories
Can become vulnerable to disruption when they are recalled, thus requiring them to be consolidated again. Called reconsolidation.
Disrupting reconsolidation
Can seemingly eliminate a conditioned fear memory in the amygdala.
Aplysia
knowledge about the neurological basis for long term memory comes from this sea slug. it has a simple nervous system consisting of only 20,000 neurons. when it’s tail is stimulated with a mild electric shock, the slug immediately withdraws it gill, and if the mild shock is done a moment later, it withdraws it’s tail even more quickly. come back an hour later, withdrawal rate is as slow as before. if the slug is shocked over and over, it can develop an enduring memory that lasts for days or even weeks. suggests this long term storage involves the growth of new synaptic connections between neurons.
long term potentiation (LTP)
process whereby communication across the synapse between neurons strengthens the connection, making further communications easier. drugs that block LTP cause short term memory loss.
retrieval cue
external info that is associated with stored info and helps bring it to mind. helps bring inaccessible info to mind.
encoding specificity principle
states that a retrieval cue can serve as an effective reminder when it helps recreate the specific way in which info was initially encoded
state dependent retrieval
the tendency for into 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
process by which retrieving an item from long term memory impairs subsequent recall of related items.
act of retrieval
can change what we remember from an experience
retrieval brain regions
regions in the left frontal lobe show heightened activity when people try to retrieve info that was presented to them earlier.
successfully remembering a past experience
tends to be accompanied by activity in the hippocampal region. also activates parts of the brain that play a role in processing the sensory features of an experience.
during memory retrieval
fMRI evidence indicates that regions within the frontal lobe that are involved in retrieval effort play a role in suppressing competitors. when hippocampal activity during retrieval signals successful recall of an unwanted competitor, frontal lobe mechanisms are recruited that help suppress the competitor. once the competitor was been suppressed, the frontal lobe doesn’t have to work as hard at controlling retrieval, ultimately making it easier to recall the target item. also causes reduced activity in the hippocampus.
Explicit (declarative) memory
Occurs when people consciously or intentionally retrieve past experiences. episodic, semantic. hippocampus is critical for these memories.
Implicit (non-declarative) memory
Occurs when past experiences influence later behavior and performance, even without an effort to remember those past experiences or an awareness of the recollection. exist outside language. priming, procedural not critical implicit memories.
Procedural memory
Type of implicit memory; the gradual acquisition of skills as a result of practice, or “knowing how” to do things. motor muscles.
People with amnesia
Can acquire new procedural memories, which suggests that the hippocampal structures that are usually damaged may be necessary for explicit memory, but aren’t needed for implicit procedural memory. Appears that regions outside the hippocampal area (including areas in the motor cortex) are involved in procedural memory.
Priming (retrieval cue)
An enhanced ability to think of a stimulus, such as a word or object, as a result of a recent exposure to the stimulus. Implicit memory. Can persist over very long periods of time. 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. Brain saves processing time after priming. tiny cues that trigger memory.
Amnesia and priming
Can show substantial priming effects even though they have no explicit memory of the objects studied. Priming does not require the hippocampal structures.
Semantic memory
A network of associated facts and concepts they make up our general knowledge of the world. Hippocampus isn’t required for acquiring new semantic memories. non-emotional, doesn’t matter where you learned it.
Episodic memory
Collection of past personal experiences that occurred at a particular time and place. Rely heavily on episodic memory to envision our personal futures. autobiographical.
Hippocampal amnesia
Individuals have difficulty imaging new experiences.
Older vs younger
Older adults provide fewer details about past experiences or about possible future events than did college students.
Neuroimaging studies
Reveal that a network of brain regions known to be in episodic memory - including the hippocampus - shows similarly increased activity when people remember past and future events.
Collaborative memory
How people remember in groups. Groups typically recall more times than an individual.
Collaborative inhibition
The same number of individuals working together recall fewer items than they would on their own. Retrieved strategies used by some members of the group may disrupt those used by others whenever group members are recalling items together.
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, first illustrated by Ebbinghaus.
Retroactive interference
Situations in which later learning impairs memory for info acquired earlier. new memories impair recall of older memories.
Proactive interference
Situations in which earlier learning impairs memory for info acquired later. older memories impair encoding of newer memories.
Absentmindedness
A lapse in attention that results in memory failure. One common cause is lack of attention. Attention plays a vital role in encoding info into a long term memory. Another cause is forgetting to carry out actions they we planned to do in the future.
Divided attention
Less activity in the lower frontal lobe. Prevents lower left frontal lobe from playing its normal role in semantic encoding and the result is absentminded forgetting. Also leads to less hippocampal involvement in encoding. Given the importance of the hippocampus to episodic memory, this may explain why absentminded forgetting is so extreme.
Prospective memory
remembering to do things in the future.
Blocking
A failure to retrieve info that is available in memory even though you are trying to produce it. Relatively infrequent, but occurs more often as we grow older. “Tip of the tongue” phenomenon.
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.
Memory misattribution
Assigning a recollection or an idea to the wrong source. may result in false recognition, misidentification, unintentional plagiarism.
Source memory
Recall of when, where, and how info was acquired. memory of the source and the context in which info was learned.
Deja vu
Misattribution can cause this. 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 situation previously.
Frontal lobes
Damage to the frontal lobes are especially prone to memory misattribution errors. The frontal lobes play a significant role in effortful retrieval processes, which are required to dredge up the correct source of a memory.
PET and fMRI
Brain scanning studies with these techniques show that many of the same brain regions are active during false recognition, including the hippocampus.
False recognition
Mistaken feelings of familiarity.
Suggestibility
The tendency to incorporate misleading info from external sources into person recollections.
Storage of details
We do not store all the details of our experiences in memory, making us vulnerable to accepting suggestions about what might have happened or should have happened. Visual imagery plays an important role in constructing false memories.
Bias
The distorting influences of present knowledge, beliefs, and feelings on recollections of previous experiences.
Persistence
The intrusive recollection of events that we wish we could forget. Occurs frequently after disturbing or traumatic experiences.
Flashbulb memories
Detailed recollections of when and where we heard about shocking events. Not entirely accurate, but better than mundane events. Enhanced retention is caused by emotional arousal, high stress, and by the fact that we tend to talk and think about these experiences a lot. Susceptible to misattribution, revision, and misinformation when retrieved and reconsolidated repeatedly.
Amygdala
Influences hormonal systems that kick into high gear when we experience arousing events; these stress related hormones, such as adrenaline and cortisol, mobilize the body in the face of threat - and they also enhance memory for the experience.
