Chapter 7: Remembering Complex Events
Memory Errors, Memory Gaps
Sometimes, when we try to remember an event, we simply draw a blank.
Other times, we recall something, but with no conviction that we're correct.
sometimes, we try to remember, things can go wrong in another way: we recall a past event, but then it turns out that
our memory is mistaken.
in some cases, we even remember events that never happened at all!
Some Initial Examples
Brewer and Treyens participants were asked to wait briefly in the experimenter's office prior to the procedure's
start. They were actually being tested on their memory of the office.
results showed participants' recollections of the office were plainly influenced by their prior knowledge - their
knowledge about what an academic office typically contains (chair, desk, folders)
this agreement between prior knowledge and the specific experience led to accurate memory
participants' recall was often in line with their expectations and not with reality
A Hypothesis of Memory Errors
Memory errors can happen in many different ways:
errors that arise during your initial exposure to the episode to be remembered
continuing through the moment of recall
errors involve the same simple mechanism; the importance of memory connections, linking each bit of knowledge in
your memory to other bits.
sometimes these connections tie together to similar episodes, certain ideas, or ideas that were triggered by some
element within the episode.
with all these connections in place, info ends up being stored in a memory in a system that looks like a spider web
within this web, there are no clear boundaries keeping the contents of one memory separate from the
contents of other memories
the density of connections is what hold together the various elements within a remembered episode
there are many connections linking the various aspects of an event
the more connections you add, the less easier it is to keep track of which bits of info were contained within which
this makes you vulnerable to what we might think of as "transplant" errors in which a bit of info encountered in one
context is transplanted into another.
Understanding Both Helps and Hurts Memory
Memory connections both help and hurt recollection.
help = connections make it easier to locate info in memory
hurt = they can make it difficult to see where the remembered episode stops and other, related knowledge
as a result, the connections encourage intrusion errors: errors in which other knowledge intrudes into the
The DRM Procedure
The presence of a word theme helps memory: the words that are on the list are relatively easy to remember.
e.g. bed, rest, awake, dream, tired, snooze, blanket, doze, nap, yawn, drowsy (all associated with sleep)
though the word "sleep" isn't on the list, participants make the connection between the list words which lead
to memory error. This is known as the DRM
Deese-Roediger-McDermott (DRM): procedure for eliciting and studying memory errors; intrusion errors from
words or ideas coming from background knowledge we bring to most situations. Schematic Knowledge
generic/schematic knowledge: it's knowledge about how things unfold in general, and knowledge about what's
typical in a particular setting.
schema: summarize the broad pattern of what's normal in a situation to you
schema tells you there are normal occurrences in a setting and you instantly understand how they fit into the
schemata also help when time comes to recalling events; you can rely on them to fill in gaps in your recollection
you'll unwittingly supplement what you actually remember with plausible reconstructions based on your schematic
Evidence in Schematic Knowledge
schemata generalizes our experience to what we see as typical or ordinary in a setting. any reliance on this
knowledge, can also hurt and shape information about what's normal.
reliance on schemata will make the world seem more "normal" than it really is and will make the past seem more
"regular" than it actually was.
elements that fit within our frame remain in our memories or could perhaps be reconstructed later
elements that didn't fit are dropped out of our memory or are changed.
Planting False Memories
memory connections can undermine memory accuracy.
connections can, in some circumstances, even lead us to recall whole episodes that never happened. (e.g. seeing a
plane crash on TV)
we rely on memory in many aspects of our lives, and it is therefore unsettling that the memories we're relying on may
be wrong - misinterpreting how the past unfolded.
the mistakes seem surprisingly frequent - with 2/3 of the participants in one study remembering books that weren't
there at all, etc.
we can easily find circumstances in which these memory errors are deeply consequential.
e.g. in eyewitness testimony, identifying the wrong person can lead an innocent person to jail
false memories can persist and have lasting behavioural effects
Limits on the Misinformation Effect
misinformation effect: when memory is being influenced by misinformation being received after an episode is over.
misinformation can change many details of how an event is remembered and can create memories that never existed
children are more vulnerable than adults to memory planting.
entire events can be planted in someone's memory so that the person ends up recalling - confidently and in detail - an
episode that never happened.
it seems relatively easy to plant these memories: two or three brief interviews, with no particular pressure, no effort
toward coercion, are all that is needed.
it is easier to plant a memory if the false suggestion is repeated, rather than delivered just once.
imagination inflation: false memories are also more easily planted if people don't just hear about the false event, but
are urged to imagine how the suggested event unfolded.
Memory errors can occur through our:
schematic knowledge; our memory for an event is connected to a schema, creating a risk that elements from
this generic knowledge will intrude into our recollection of the target episode
DRM procedure; errors in memory episode trigger certain thoughts which connect to the target memory and
can intrude into the recall.
misinformation effect; errors arise because different episodes get linked together in memory, allowing
elements of one episode to intrude into the other. Accurate Memories
In our daily lives, we usually can trust our memories.
our recollection is complete, detailed, long-lasting and correct.
The Importance of the Retention Interval
retention interval: the amount of time that elapses between the initial learning and the subsequent retrieval.
as the retention interval grows, you will gradually forget more and more of the earlier event, and so forced to rely
more and more on after-the-fact reconstruction to fill the gaps in the memory record.
if you forget the details of an episode, it will become more difficult to distinguish which elements were actually part of
the event and which ones were associated with the event in your thoughts.
source monitoring: remembering the source of the various ideas that are associated with an event in your thoughts.
as time goes by you will have more difficulty in source monitoring.
this in turn, increases risk of intrusion errors
decay: memories may fade or erode.
this may occur because the relevant brain cells die off
or perhaps connections among memories need to be constantly refreshed, if not they gradually weaken
memories decay with passage of time but is far from inevitable
interference: less is remembered about older events because the passage of time allows new learning, and it is the