Transcript Effects of Filled Delay in Implicit and Explicit memory

Effects of Filled Delay in Implicit
and Explicit memory
Laura Steel and Louise
Connor
Outline
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Introduction
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Background Research
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Our Design
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Our Prediction
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Problems encountered
Introduction
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There are many studies concerning implicit and explicit
memory.
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Implicit memory - a lack of conscious awareness when recalling
information.
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Explicit memory – e.g. memories for events, people, places and
objects.
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Study of implicit memory began in the early 1980’s.
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Implicit memories have a large impact on the decisions we
make as humans.
Introduction
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Tasks that involve implicit memory include:
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Tying shoes
Riding a bicycle
Walking
Tasks at work, such as remembering details of an
earlier telephone call.
Tasks at school, such as revision of previously
read information.
Introduction
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Implicit memory is interesting and unique in the
sense that it does not require conscious awareness;
information can manifest itself in our thought
processes without us even knowing about it.
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Practical examples of implicit memory
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studies on amnesiacs demonstrate that they still possess
implicit memory skills.
subliminal messaging, which can occur in advertising, selfhelp tapes and language learning tapes.
Background Research
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This project is based on a study by F. B. Gershberg
and A. P. Shimamura (1994). It observed serial
position effects in implicit and explicit tests of
memory.
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A between-subjects design was used by Gershberg
and Shimamura. They gave an incidental learning
task to all participants. Participants then either
completed a free recall exercise, an implicit wordstem completion task, or explicit cued recall.
Background Research
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The study was split into three separate
sections. The independent variable was
manipulated differently in each.
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We adopted the second section of their
investigation, in which they added a filled
delay between the incidental learning task
and type of recall.
Background Research

Gershberg and Shimamura used the filled delay
mainly to reduce ceiling effects in the explicit
condition, whereas we want to examine how different
types of filled delay affect implicit and explicit tests of
memory.
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We will observe whether serial position effects are
present in our results, but our main focus is the
effects of two types of filled delay.
Our Design
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One of our filled delay tasks is taken from the
original experiment. This is a word-stem completion
task.
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We will compare the effects of this with a circuit
tracing task as our second type of filled delay.
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The test condition will be the same for all participants
and will consist of an incidental learning task.
Our Design
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The words were obtained from ‘The Corpus’
(Kučera and Francis, 1967), which lists how
frequently English words occur per million of
words.
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We randomly selected 24 nouns and paired
them by frequency of occurrence, so that we
had two lists of 12 words as our study
material.
Our Design
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The incidental learning task will consist of the
words being presented on a computer screen
using Microsoft Powerpoint™.
Paint
Pa ___
Our Prediction
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We predict that there will be a difference between
the two types of filled delay used in the experiment.
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In theory, the motor task does not use the
hippocampus whereas the stem-completion task
does.
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We aim to find how and if this affects incidental
learning.
Our Prediction
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Gershberg and Shimamura had to discard
some of their results because participants in
the implicit word-stem completion condition
had guessed that they had to remember
previous words.
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Since one condition in our experiment uses a
different filled delay task to the study task, we
will be able to see if it eliminates this factor.
Problems Encountered
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Finding a way of presenting the words to
participants.
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Choosing which statistical analysis to use.
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The complexity of what to examine based on
the original experiment.
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Counterbalancing.