Memory and Memory Errors

Memory and Memory Errors:
Covered topics include:

  • Autobiographical Memory: A type of memory that involves recollection of personal experiences from one’s life, which shape identity and influence behavior.

  • Influence of Music and Odor: Sensory stimuli such as music and specific odors can trigger vivid memories and emotional responses. For instance, a particular song might bring back memories of a significant event, while certain scents can evoke nostalgia.

  • Exceptional Events: Memory is often enhanced for significant or traumatic events, leading to what are termed flashbulb memories, which are detailed and vivid memories of shocking events.

  • Focus on Memory Creation and Misinformation Effects: Investigates how newly acquired information can alter our recollections of prior events, often introduced through misleading information following the original event.

Constructive Nature of Memory
Why We Remember:

  • Significant experiences: Events such as weddings, graduations, and births are often remembered clearly due to their emotional intensity and personal relevance.

  • Events from specific life periods known as the reminiscence bump, typically between ages 10-30, where individuals have heightened recall for events that shaped their identity during formative years.

Memory Representation:
What we remember can differ from actual events due to:

  • Omission: Important details may be left out of our memories.

  • Distortion: Details of events can be misremembered or altered.

  • Change: As time goes on, memories might blend with other experiences.

  • Addition: New information may be integrated into existing memories, creating inaccuracies.

Factors Influencing Memory
Memories are influenced by:

  • Semantic knowledge: General knowledge accumulated over a lifetime can lead to expectations that shape how we remember events.

  • Episodic experiences: Specific, personal experiences can color our recollections of similar events.

  • Expectations: Prior knowledge and beliefs can influence the way we interpret and remember events.

  • Source Monitoring: A process of determining the origin of our memories.
    Example: Remembering a song’s source (friend, party, media).
    Errors in this process can lead to misattributed sources, known as Source Monitoring Errors.

Error Types and Effects
Source Monitoring Errors:
Common errors in memory attribution, such as misremembering where a song was heard and confusing the source of knowledge.

  • Cryptomnesia: Unconsciously recalling someone else's work as our own, leading to instances like musical plagiarism without intent.

  • Jacoby et al. (1989): Conducted a study investigating familiarity and source errors using famous versus non-famous names, concluding that familiarity can lead to misattribution of non-famous names as famous.

Illusory Truth Effect
Definition: A cognitive bias wherein repeated statements are perceived to be more truthful regardless of their actual veracity.

  • Illusory truth effect highlights how exposure can distort our perception of reality, leading to the inadvertent reinforcement of false information.

  • Study by Fazio et al. (2015): Participants were exposed to a mix of true and false statements and later assessed based on their evaluations of truth; findings showed that repeated statements were rated as true more often.

  • Fluency: The ease with which information is processed affects judgments, leading to misperceptions in recalling the truth of statements.

    • Increased familiarity with statements can create a false sense of accuracy, further complicating our ability to discern fact from fiction.

Memory vs. Real-World Knowledge
Bartlett’s “War of the Ghosts” Study (1932):
Investigated how memory distortion occurs over time as participants reconstructed an unfamiliar story influenced by their own cultural knowledge and schemas, highlighting the differences between actual events and recollections shaped by pre-existing knowledge.

  • Had participants try to remember a story from a different culture

  • Used repeated reproduction technique: participants had to try to remember the story over longer and longer intervals of time after the first read

  • Reproductions were shorter over time and reproductions contained omissions and inconsistencies

  • As time went on, changes to the story reflected participants making the story more consistent with their own culture

Making Inferences in Memory
Pragmatic Inference:
A person believes something, even though it is not explicitly stated or implied in the sentence, image, or situation but based on knowledge from experience

  • Memories influenced by experiences and knowledge

  • Brewer (1977) and McDermott & Chan (2006): Participants read sentences then the participants were presented with the same sentences, but with blanks to fill in. One third of the time, participants used different, similar, words e.g. used “collapsed” instead of “weakened”

    • They inferred what would happen

  • Schemas and Scripts: how knowledge influences memory by providing guidelines for making inferences

  • Schema: Organized frameworks of knowledge about environments shaped by prior experiences, affecting how future experiences are processed.

  • Script: Expectations regarding sequences of actions in specific contexts (e.g., how a restaurant meal typically unfolds).

Memory Creation and Misinformation
Misinformation Effect:
Refers to the phenomenon where misleading information presented post-event alters a person’s perspective and recollection of the event itself.

  • Misleading Post-event Information: The misleading information that causes the misinformation effect

    • MPI affects what people say they saw, in addition to the conclusions and characteristics they draw from certain situations

    • Linked to source monitoring where MPI is used as source


Study by Loftus (1978):
Demonstrated that the wording of questions manipulated eyewitness recall (e.g., whether a stop sign or yield sign was present), illustrating the power of suggestive questioning.

Memory Creation

  • Creating Childhood Memories: A study by Wade et al. (2002) showed that suggestive techniques could lead to implanted false memories, such as participants recalling a fictitious hot air balloon ride.

    • People were more likely to recall the “hot air balloon ride” after being shown pictures of the event, even though it never actually occurred, highlighting how visual cues can enhance the creation of false memories.

  • Repressed childhood memory: Memories that were pushed out of one’s consciousness

    • Therapists hypothesized that repressed childhood memories caused psychological problems

      • Treat patient by retrieving memory

      • Many court cases against therapists, who often used techniques such as: Hypnosis Guided Imagery Strong Suggestion

Eyewitness Testimonies
Importance: Eyewitness testimonies can provide crucial evidence in legal settings, yet they are often riddled with inaccuracies.
Common Errors in Testimonies:

  • Misidentification: Resulting from limitations in perception, selective attention, and suggestive prompts.

  • Three common errors: Perception and attention, Misinformation from familiarity, Suggestion

    • Perception and attention:

      • Difficult to accurately identify a perpetrator after watching a videotape of a crime

      • There is a strong inclination to pick someone as a perpetrator, even if they aren’t included in the lineup or photos

      • Emotions can affect what people pay attention to and, subsequently, what they remember

      • Weapons focus: Tendency to focus attention on weapons

        • Narrows attention because people are focused on the weapon, not the crime as a whole

    • Misinformation from familiarity:

      • Crimes usually involve: a perpetrator, a victim, and bystanders Bystanders might mistakenly be identified as perpetrators- This is a source monitoring error

      • Ross et al. (1994): In their study about eyewitness testimony they showed participants the video of a male teacher reading to his students followed by a video of a female teacher being robbed. Then they showed participants a photo spread that did not contain a picture of the robber. Under that condition, most participants identified male teacher as the perpetrator.

    • Suggestion:

      • Example: Police lineup “Which of person in the lineup committed the crime” Implies the perpetrator is actually in the lineup, even if they aren’t Increases chance that an innocent person will be chosen

      • Post-identification feedback effect: Increase in confidence of identification decision based on confirming feedback from officer (Can be as simple as the word “okay”)

      • This effect can lead to overconfidence in a witness's memory accuracy, ultimately impacting legal outcomes.

Cognitive Interview:

  • Let the witness talk with little interruption

  • Use techniques to help witnesses recreate the situation

  • Have them place themselves back at the scene

  • Recreate emotions, points of view, how it would look from different POVs which decreases likelihood of suggestions by interviewer

  • Disadvantage: takes more time


Recommendations to Improve Lineup Procedures:

  • Inform witnesses that the perpetrator may not be present in the lineup.

  • Use similar fillers to the suspect in lineups to avoid bias.

  • Utilize administrators unaware of the suspect's identity to prevent inadvertent cues.

  • Obtain immediate confidence ratings from eyewitnesses after identification to gauge reliability.

Impact of Suggestion and False Confessions
Eliciting False Confessions: document how suggestion and social pressure can compel individuals to falsely confess to crimes they did not commit.
Studies by Nash & Wade (2009):

  • Participants played gambling game on computer and some participants were shown fake video of them cheating

    • All those participants confessed, even though they didn’t cheat

    • Some participants were told they cheated, but were not shown a video 73% of the participants confessed to cheating

Shaw & Porter (2015):

  • Participants made to believe they committed a crime that involved police

  • Presented with a true event from age 11 to 14 and presented false event of committing a crime. The participants remembered the true event and didn’t remember the false crime event. After the Interviewers used social pressure and guided imagery the participants interviewed 1 and 2 weeks later and 70% said they remembered false event, and they even gave details

The Central Park Five:

  • White woman raped in Central Park in 1989. 5 Black and Hispanic boys, who were innocent, brought in for questioning were found guilty based on their confessions after being aggressively interrogated for 14 to 30 hours, the police used false evidence to convict them

  • Convictions reversed in early 2000s

    • This high-profile case exemplified the significant repercussions of false confessions obtained under duress, resulting in wrongful convictions and highlighting systemic issues within the criminal justice system.