4. Memory manipulation - gleneaglesyear12psychology

Memory….Accurate 

Research findings indicate that much of what we recall from LTM is NOT an accurate representation of what actually happened previously.

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Memory includes some exact details but also some additions that are logically plausible, things that might have happened, filtered and shaped by our thoughts, attitudes and beliefs as well as by who we are as individuals and social beings.

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Human memory is able to remember relevant fragments of what we experience, but is prone to errors and distortions.

Memory….Accurate 

Unlike a camera or audio recorder that captures a perfect copy of information, the details of human memory can change over time.

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Without our conscious awareness, details can be added, subtracted, exaggerated or downplayed.

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Confidence in memory is no guarantee of its accuracy, in fact there is little correlation.

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Some researchers believe that strong confidence in the memory of minor details may actually be a cue that the memory is inaccurate or even false. (Reisberg, 2007; Hockenbury & Hockenbury, 2006)

Why so many errors? 

Memory is not simply recorded but actively constructed

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To form a new memory you actively organise and encode different types of information (visual, auditory, tactile etc.) When you later attempt to retrieve this information, you actively reconstruct or re-create the details of your memory.

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Over time recalling memories can change the content and meaning of a memory

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Your experience of memory is NOT a guarantee that it reflects reality!

Bartlett’s research on manipulation of memory 

British psychologist Frederick Bartlett in 1932 first drew attention to the reconstructive nature of human memory.

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Bartlett believed Ebbinghaus studied human memory in an artificial way. E.g. Using nonsense syllables to control influence of past experience excluded important variables that impact on human memory in everyday life such as the influence of our prior experiences, attitudes and expectations.

Bartlett’s research on manipulation of memory  Participants read prose (story or essay) or looked at a picture. 

Participants were asked to recall and describe the prose or draw the picture on several later occasions.

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Each time the original stimulus material was remembered slightly differently. e.g. Unusual or unexpected events were described in a more logical or sensible way (as if to match their personal beliefs of what might likely be true).

Bartlett concluded that we tend to remember only a few key details of an experience, and that during recall we reconstruct the memory, drawing on our personal values, beliefs, and expectations to make up and add missing bits in ways that complete the memory in a logical or plausible way. Usually done without conscious awareness of it happening.

Loftus’s leading question research 

Other studies have confirmed Bartlett’s conclusions and extended his findings.

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U.S. Psychologist Elizabeth Loftus and various colleagues on eyewitness testimony.

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Loftus found that eyewitnesses similarly reconstruct their memories and their testimony is therefore not always accurate.

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Many of Loftus’ studies involve showing participants a short film, video or slides of an event such as a car accident and then asking them specific questions about the scene they “witnessed”.

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Sometimes information that was not present in the actual scene or which contradicts the scene is introduced. At other times, leading questions are asked.

Loftus’s leading question research 

The way questions are asked during eye witness testimony can influence memory

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Shows how recall does in fact involve an active reconstruction of events, that is open to suggestion

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Leading Questions – are questions that have content or are phrased in such a way that suggests what the desired answer is or to lead to the desired answer.

Example of a “Leading Question” e.g. To a witness of a car accident “How fast was the car going when it ran the stop sign?” This is a leading question according to Loftus (1975) because it contains a preposition (i.e. Information that should or must be true in order for the question to make sense). The question presupposes or assumes there was a stop sign. But what if there was no stop sign? The witness might answer the question anyway because it was a question about how fast the car was going and not a question about the presence of a stop sign or whether the car ran the stop sign. Loftus proposed that the way the question was worded the witness might add the new false information about the stop sign to their memory of the event. Then they would be more likely to recall it as a part of their reconstructed memory when answering a question about it such as “Did you see a stop sign?” at a later time.

Loftus’s leading question research – study no. 1 

One of Loftus’ research on memory reconstruction was conducted with US colleague John Palmer (1974). Two lab experiments that investigated the influence of question wording on memory and how information supplied after an event can distort a witness’s memory for that event.

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45 volunteer uni student participants shown 7 clips of car accidents. Clips were short excerpts from driver education films ranging from 5 to 30 seconds long.

Loftus’s leading question research – study no. 1 

Participants were asked to write a description of the accident after viewing each clip.

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Also participants were asked to answer some specific questions about the accident, including a critical question requiring an estimation of speed of the cars involved in each collision.

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There were 5 conditions in the experiment, with 9 participants randomly assigned to each condition.

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Each condition had a different verb used to complete the critical question (therefore different versions of the question were asked).

Loftus’s leading question research – study no. 1 

All participants asked the question – ‘About how fast were the cars going when they________ each other?’

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The gap was filled with Smashed (Condition 1) Collided (Condition 2) Bumped (Condition 3) Hit (Condition 4) Contacted (Condition 5)

Loftus’s leading question research – study no. 1 

To control the potential influence of the order in which the clips were viewed, the clips were presented in a different order to each group of participants.

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The most “intense” verbs resulted in the highest speed estimates and the least “intense” in the lowest speed estimates. See table on next slide.

Differences in speed estimates were found to be statistically significant at p