Course: PSYC*1000 (DE)
Professor: Harvey Marmurek
Schedule: Summer, 2012
Textbook: Psychology – Tenth Edition in Modules authored by David G. Myers
Textbook ISBN: 9781464102615
Module 26: Forgetting, Memory Construction, and Improving Memory
Why do we forget?
Forgetting and the Two-Track Mind
For some, memory loss is severe and permanent. Henry Molaison (H.M.) had brain surgery to stop severe
seizures but was then unable to form new conscious memories. Suzanne Corkin neuroscientist. He suffered from
anterograde amnesia, able to recall his past but not form new memories.
Oliver Sacks – Jimmie had no memories beyond his injury in 1945.
Although incapable of recalling new or recent facts or events, they can learn nonverbal tasks. Can find their
way to the bathroom without being told again, read mirror-image writing, find Waldo, complicated job skills – all
classically conditioned; but with no awareness of having learned them. Lost ability to form new explicit memories.
Age can affect encoding efficiency. The brain areas that jump into action when young adults
encode new information are less responsive in older adults.
Eternal Events Sensory Memory (attention) Working/short-term memory –> (encoding) long-
term memory storage
*Encoding failure leads to forgetting
Hermann Ebbignhaus learned nonsense syllables and measured how much he retained from 20
minutes to 30 days later. The course of forgetting is initially rapid, then levels off with time.
Harry Bahrick – Spanish vocabulary in school, 3 years out of school and forgotten much of what
they had learned, but that which they remembered at that time was still recalled 25 years later. Some
memories are never encoded. Others are discarded.
Sometimes important events defy our attempts to access them – a name at the tip of the tongue. Retrieval
problems occasionally stem from interference and, perhaps, from motivated forgetting.
Attic never fills, but it does get cluttered; ability to tune out clutter; focus. Those who were better at
forgetting the irrelevant pairs also focused more on the to-be-remembered pairs and recalled them better on later
Sometimes, however, clutter wins, and new learning and old collide. Proactive (forward-acting) interference
occurs when prior learning disrupts your recall of new information (buy new lock, forget old combination).
Retroactive (backward-acting) interference occurs when new learning disrupts recall of old information (sing
lyrics to the tune of an old song).
Info presented one hour before sleep is protected from retroactive interference because the opportunity for
interfering events is minimized. John Jenkins and Karl Dallenbach – nonsense syllables day after day, recalling up
to 8 hours after being awake or asleep at night; forgetting occurred more rapidly after being awake and involved in
other activities. Learning while sleeping – little memory for info. Old and new learning do not always compete with
eah other – positive transfer.
Memory fails us because memory is an unreliable self-serving historian. Sigmund Freud – memory systems self-
censored this information; we repress painful or unacceptable memories to protect our self-concept and to minimize
anxiety. Can be retrieved by some later cue or during therapy. Educated people believe in repressed memories
more than those with less formal education. Sensory Memory – The senses momentarily register amazing detail
Working / Short-Term Memory – A few items are both noticed and encoded
Long-Term Storage – Some items are altered or lost
Retrieval from Long-Term Memory – Depending on interference, retrieval cues, moods,
and motives, some things get retrieved, some don’t.
What are three ways we forget, and how does each of these happen?
(1) Encoding failure: information never entered our memory system because we were not paying attention
to it, or the information was entered inaccurately. (2) Storage Decay: information fades from our memory. (3)
Retrieval failure: we cannot access stored information accurately, sometimes due to interference or motivated
Memory Construction Errors
How do misinformation, imagination, and source amnesia influence our memory construction? How do we
decide whether a memory is real or false?
Memory is not precise. Information acquired after an event alters memory of he event. We often construct
our memories as we encode them, and every time we replay a memory, we replace the original with a slightly
modified version. Your memory is only as good as your last memory. To some degree, all memory is false.
Misinformation and Imagination Effects
Elizabeth Loftus, eyewitnesses, traffic accident – language, leading questions. Misinformation
Effect – exposed to misleading information, we tend to misremember.
Once eating a spoiled sandwich and either never eating that kind of sandwich again or eating from
the place where the sandwich originated from – imagination. Digitally altered photos have also produced
this imagination inflation. The more vividly we can imagine things, the more likely they are to become
Among the frailest parts of a memory is its source. Did the dream really happen?