unit 6 memory

autobiographic memories

1. these are the memories that we hold regarding ourselves, our interactions with the world around us

2. these memories help to define us who we were at different time points

3. they are episodic memories that form part of our life stories → specific events tied to time and place, they are vivid and detailed

4. they also include semantic autobiographical memory that includes historical facts, traits and knowledge states that are NOT unique to any particulat place or time (e.g. general fact abt your life → i have lived in spain)

autobiographic memories are made up of 2 parts:

1. generalized knowledge of events (semantic)

2. specific memories (episodic)

autobiographical knowledge base

• these are facts about ourselves and our past that form the basis of autobiographical memory (like where were you born)

• autobiographical memory has hierarchial structure with an overall life story being linked to subsidary themes (these themes help to organize)

  • they are conceptualized at relatively abstrace level but can lead to specific episodic memories

autonoetic consciousness

• this is the capacity to reflect on our thoughts → the “self aware” part of the memory

• this ability to reflect on out memories is essential in deciding whether the recollection is an accurate record of the past or is it a made up/distorted memory that feels real but is not accurate

methods of studying autobiographical memories

1. using diaries

2. cue word technique

3. time-based cues (giving a specific date or period)

4. brain damage studies → shows what is lost and what remains

diaries

• older diary entries are harder to recall, unless they are tested more than once (because repeated retrieval strengthens memory)

the most effective cue words for recalling events

• who

• what

• where

the least effective cue word(s)

• when (date only provided)

• this is because we remember people, actions and location than just time

autobiographical can be difficult to remember and unpleasant, but..

with the right cues even the most thoughest memories can ve eventually be recalled

results of the study where P were recording diaries with events and thoughts

• events were 2x as much more remembered than thoughts

• real events were easier to recall than fake but possible events → this shows that doing something makes it more memorable than just thinking about it

• actions are remembered better than thoughts → the more unique action the more likely it is to be remembered

results from Galton’s study where he provided P with a word and asked them to recollect an autobiographical memory associated with it

• P tend to recall few autobiographical memories from the first 5 years of life → infantile amnesia

• P tend to produce the most memories from the most recent period

• there is a marked increase in memories between 15 to 30 = reminiscence bump

reasons for infantile amnesia

1. rapid rate of increase in new neurons in hippocampus (may disrupt the stability of early memory traces)

2. harder to reinstate memories prior to their inclusion (memories formed before the hippocampus was fully developed or connected are hard to access later in life)

3. absence of coherent concept of self during infancy + absence of general set of schemas (the world is not organized yet, so no memory can be retrieved)

4. infantile amnesia in many diff species of non human anumals

reminiscence bump

• this is a tendency in P over 40 to show a high rate of recollecting personal experiences from their late teens to early 20s → as this is a period where a lot of important things happen

• reminiscence bump is NOT limited to episodic memories (specific personal memories), it also includes semantic memories + preferences and cultural memories

• things learned in early adulthood are remembered the best

  • people stick with books, music etc. from this period emotionally

  • people judge political events that occurred during this period as especially important + they know more about them → this is because they were paying more attention and their emotional and social itensity strengthens memory

reminiscence bump include..

1. episodic memories

2. semantic memories

3. preferences and cultural memories

3 reasons for reminiscence bump

1. maturational hypothesis → our cognitive capacities are at peak during this period

2. life narrative hypothesis → this stage of life is when one creates and takes on their adult social identities

3. cognitive hypothesis → encoding is the best during periods of rapid chance (memories stabilize after 30s because not that many new events stand out)

immigrant second remeniscence bump study

• they showed their 2nd reminiscense bump when they moved

• this supports life narrative hypothesis (big identity shift) and cognitive hypothesis (rapid change)

a reminiscence bump was found for…

positive events, over which participants felt they had high degree control over

• reminiscence bump is not only about age - it is also about emotion and agency

• people remember positive, self-directed experiences more vividly from young adulthood

• events where we felt more responsible or proud are more likely to be stored and recalled

positive bias

• positive memories are more likely to be remembered, while negative memories fade or become less vivid

• the older the memory the stronger the bias becomes → the mind preserves good memories and blurs negative memories or makes them less accessible

fading affect bias

• this is the consistent tendency for the negative memories over time to lose affective intensity at a higher rate than positive memories

  • positive memories fade too but just at slower rate

  • the fading happens regardless whether the emotion was active (angry, excited) or passive (sad, calm)

• most people thought that positive emotions fade faster than negative emotions

life narrative

• it represents a coherent account that we are creating for ourselves throughout our lives

• this is the story of who we are and how we got to this point

events that influence our life narrative are more likely to be:

• important to us

• retrieved

• more deeply encoded

• emotionally intense, which is a factor that increases the accessibility of our memories

flashbulb memories

• they are detailed, vivid and highly accurate memory of a dramatic experience

• extreme emotion is assumed to lead to an almost photographic representation of the event and its physical context

• but they are NOT 100% precise → they can include incorrect or inexact details

  • 3 years later, 1/3 of the P showed confident but completely false accounts of what had happened → and they did not give up on these memories easily, even when they were given contradictory evidence

emotions in memory

• when memory of emotions is aroused by new event → it is also vulnerable to distotrion

  • even though emorional events feel unforgettable and vivid → they are NOT immune to distortion

  • when something new or dramatic happens (like a tragedy) it activates strong emotions → but what we remember about it can still change over time

• memories can be substatnially skewed by current views, emorions or social attitudes

  • like if you do not trust someone now, then you might remember the past interactions as more negative than they actually were

study with concentration camp surviors right after WWII and 40 years later

survivor’s memories of important events (like violence or liberation) were generally stable and consistent, but not perfect → some details were forgotten, added or misremembered

highly superior autobiographical memory people

• they are extremely good at recalling public events and dates

• they performed the same as “normal people” on tests like → standard tests of episodic memory, paired associations (remembering word pairs), backward/forward digit span

• they performed slightly better at remembering face-name associations

• in the personality scores there were no differences, but they tend to score higher on obsessionality (strong routing + repetitive thought pattern)

• brain activity → superior functional communication btw PFC and hippocampus

what is the brain activity in highly superior autobiographical memory people?

superiod functional communication between PFC and hippocampus

severely deficient autobiographical memory people

• these individuals have normal memory for facts and tasks, but they cannot recall personal life episodes in a vivid or detailed way

• cognitive and neuropsychological test → normal range or higher on nearly all standardized intelligence and memory tests

• rey complex figure test (RCFT) → severely impaired in delayed condition

  • this test requires to reproduce a complex drawing after some time has passed

  • this suggests difficulty in visual-episodic recall

• brain activity → reductions in medial prefrontal cortex and posterior midline regions, including precuneus

  • their brain shows reduced activity in areas tied to:

    • self-referential thinking

    • scene construction

    • mental time travel

  • these areas are critical for autobiographical recall and imagining oneself in the past events

in which test do the severely deficient autobiographical memory people perform the worst?

Rey complex figure test → their results are severely impaired in delayed condition

→ deficits in visual-episodic recall

what brain areas do the severely deficient autobiographical memory people are the most impacted?

• reductions in medial PFC

• reduction in midline regions (and precuneus)

their brain shows reduced activity in the areas tied to self-referential thinking, scene construction and mental time travel (they are all essential for autobiographical recall)

gender differences in autobiographical memories

• women have slightly better memory for life experiences

• wives have so much more vivid memories than their husbands of past events in their lives together

• women may reminisce more about social events than men → therefore creating more vivid memories

• women also are more accurate in dating past events

psychogenic amnesia

• extreme, emotional distress can lead to dramatic forgetting that can severely disrupt everyday life due to loss of personal memories

• this is primarily due to psychological damage, not physical damage to the brain

psychogenic amnesia is usually due to:

• severe crisis (like divorce or violence)

• past or current history of clinical depression and other disorders

• prior history of head injury or other neurological symptoms → although this may never be directly tied to this

psychogenic amnesia, fugue state

• this is a type of psychogenic amnesia with extreme memory loss + identity disruption

• complete loss of autobiographical memory (who am I?)

• person may wander or travel without knowing how or why

• usually resolves quickly (days or weeks)

from fugue state of psychogenic amnesia to focal retrograde amnesia (FRA)

• FRA is a longer lasting version of fugue related memory loss

• it starts off as fugue state (identity loss)

• but with time identity is re-learned or rediscovered → but autobiographical memory remains impaired, especially for older life periods

focal retrograde amnesia

• loss of personal memory without fugue (identity loss) or travel/wandering

• identity is INTACT

• it is sudden + persistent loss of autobiographical memory (like childhood memories)

• it is like a box that is locked away and you do not want to open it → defensive psychological block

gaps in memory, a type of psychogenic amnesia

• abrupt, localized memory loss

• no identity loss

• loss of specific time periods → multiple blackouts or missing chunks

• often linked to trauma + dissociation

PTSD

• occurs after a traumatic or extreme stress event

• it is a mental health condition that affects both emotion + memory

• after stress, normally your body produces stress hormones (like adrenaline and cortisol) and after the danger passes, the brain tells the body to stop to release the hormones and therefore this allows the body to return to a calm, normal state

  • BUT in PTSD this corrective process is reduced → the off switch for stress hormones does not work properly, so as a result there is a prolonged state of stress , even when the danger is long gone - this makes the trauma feel ongoing, not in the past

role of hippocampus in PTSD

a reduced hippocampus makes one vulnerable to PTSD → because smaller hippocampus is less able to recover from a surge in adrenaline, which is associated with extreme stress (stuck in hyperarousal and fail to regulate body’s stress hormones)

key symptoms of PTSD

1. flashbacks

2. nightmares and intrusive thoughts that repeat the trauma

3. avoidance of places and people related to trauma

4. chronic anxiety → general ongoing state of fear, tension or unease

recalling what was said in conversation

• recalling a convo is never word for word → memory for this recall is very low, even after convo

• it is common to forget the words + basic info (like who said it and when)

results from a study where uni seminar was recorded for an entire term and students were tested after

• recalls were generally sparse → people remembered very little, most of the convo details had faded

• there were few errors → the little people remembered was accurate

• P seemed to choose a level of specificity at which what they said was essenitally correct → people tended to remember the general idea, not the details

  • they avoided the mistakes by recalling just broad themes

• P did not remember better what they said themselves than what others said → no self memory advantage

memory for conversation is positively correlated to

social competence → people who are socially skilled (good at listening, interacting etc.) tend to have better memory for what was said

memory for conversation is negatively correlated to

social anxiety → people who experience social anxiety tend to remember convos less accurate or less in detail

since most memory studies on eyewitnesses are done in controlled lab settings (using videos or photos of crime scene)…

you cannot generalize this because being a witness or victim involves much more higher arousing experience

field studies of crime and eyewitness testimony have identified certain aspects of the eyewitnesses that could later affect the identification accuracy:

1. characteristics of the target

2. duration of the interaction

3. context at questioning (where, when and how the witness is questioned → can influence memory retrieval)

children’s testimony

• children can testify only after repeated questioning by potentially biased interviewers

• children free recall is accurate but sparse → especially young kids provide little info on their own

• directive + leading Q can elicit incorrect info (kids may say yes because of the pressure)

• preschoolers are particularly susceptible to repeated suggestive questioning (because they confuse real vs imagined events, they want to please the adult, are unable to resist strong suggestions)