The Effect of Motor Action on Emotional Memory
The Effect of Motor Action on Emotional Memory
Douglas Moritz
dlm58@pitt.edu
6/17/2011
INFSCI 2300
Human Information Processing
University of Pittsburgh, Pittsburgh PA
1.
Introduction
In this article, I will attempt to analyze and explain the following question: Can seamless
everyday bodily actions affect our retrieval of memories and the emotional state at which they
are retrieved? “Bodily actions associated with positive and negative emotional valence can
influence retrieval of emotional memories” (Casasanto & Dijkstra, 2010, p. 179). Even actions as
simple as standing up straight or slouching in a chair, in essence our basic posture, can affect our
emotional valence and as such our retrieval of memories during said emotional state. In a study,
participants in one condition were instructed to smile and to stand in an upright erect position
while they recalled pleasant or unpleasant experiences in their lives and other participants under
a different condition were instructed to have a downcast expression and to have their head, neck
and body slumped while they recalled pleasant or unpleasant experiences from their lives
(Dijkstra, Kaschak & Zwaan, 2007). The results showed that when participants postures and
facial expressions were congruent with the emotional valence of those life experiences access to
pleasant or unpleasant experiences improved more than when postures and facial expressions
were incongruent with the emotional valence of those life experience (Dijkstra, Kaschak &
Zwaan, 2007).
It seems apparent from the study mentioned above, in summation – asking some
participants to smile and then to recall an event and others to frown and then to recall an event,
that there is a correlation between our actions and the emotional valence of those memories
during retrieval (Dijkstra, Kaschak & Zwaan, 2007). However, some everyday actions such as
smiling, frowning, slouching, breathing etc. may naturally affect the way we think and feel, at
least in the moment we are exhibiting such actions. What about actions that may not naturally
have a direct effect on emotional valence? In Section 2, we will discuss seemingly meaningless
everyday actions and whether or not they can affect our retrieval of memories and the emotional
state of retrieval. For further analysis, I will also review some additional studies regarding
posture, motor action and mental metaphors in relation to memory and emotional valence.
2.
Background
According to Tulving, the encoding specificity principle (as cited in Casasanto &
Dijkstra, 2010, p. 180), recall is better enabled when the characteristics of retrieval context
correspond with aspects of the contexts in which memories were encoded. When a person
remembers an experience while assuming a similar body position to the original experience, this
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The Effect of Motor Action on Emotional Memory
congruent body position can improve retrieval of memories related to bodily actions (Dijkstra,
Kaschak, & Zwaan, 2007). Feelings of energy and happiness can be connected with experiences
of smiling and sitting upright, while feelings of sadness and laziness can be associated with
experiences of frowning and slumping. Therefore, encoding specificity suggests another
explanation, that non-metaphorical representation of prior reports of interactions for emotional
valence and between bodily actions (Casasanto & Dijkstra, 2010). Basically, the retrieval of
information is more likely to be effective when the emotional state at the time of retrieval is
similar to the emotional state at the time of encoding.
Before continuing to discuss everyday actions and seemingly meaningless actions, how
would someone’s ability to recall a particular memory be affected if a person’s emotional state
either at the time of encoding or retrieval was to an extreme (e.g., very stressed)? In a study, De
Kloet, Joels and Holsboer analyzed GC (GCs; corticosterone in most laboratory animals, cortisol
in humans) (as cited in Wolf 2008, p. 514). Causing negative feedback to several levels of the
HPA axis, De Kloet et al., concluded the increase of cortisol (stress) levels also influences other
parts of the brain (as cited in Wolf 2008, p. 514). In another study using rats as the subjects, De
Quervan, Roozendaal and McGaugh found that even while under the influence of stress or GC,
can have positive effects for the storage of information while having negative effects on memory
retrieval (as cited in Wolf 2008, p. 516).
Figure 1: From “Summary of GC effects on different memory forms in rodents and humans” by O.T. Wolf, 2008,
Acta Psychologica 127, p.516.
Lakoff & Johnson point out that often when talking about emotions, individuals
frequently use expressions that connect upward motion or position in space (e.g., he’s high on
life) to a positive valence and downward motion or position (e.g., he’s feeling down ) with a
negative valence (as cited in Casasanto & Dijkstra, 2010, p. 179). Thereby, in accordance to the
theories of metaphorical representation, these linguistic metaphors seemingly correlate to
‘mental metaphors’ (Casasanto, 2009). It’s possible that people can learn mental metaphors from
patterns in our everyday culture and language (e.g., “thumbs up” and “thumbs down” for
approval and disapproval) (Casasanto, 2009).
We have seen from several studies that actions with some tone or hint of meaning such as
posture, facial expressions, GC or stress and other emotions can affect our emotional valence and
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The Effect of Motor Action on Emotional Memory
memory retrieval. As such, now that we have briefly looked at different conditions that may
directly affect our emotional valence and memory retrieval, we can now try to answer our initial
question: Can seamless everyday bodily actions affect our retrieval of memories and the
emotional state at which they are retrieved?
In a related study, the purpose was to conclude whether motor actions that are unrelated
to the encoding of emotional memories can still have an effect on their retrieval, consistent with
the mental metaphor “positive is up / negative is down” (Casasanto & Dijkstra, 2010). In two
experiments, participants were asked to retrieve and report autobiographical memories while
moving marbles in upward or downward direction when prompted. The prompts during the first
experiment dealt with either positive or negative valence (e.g., tell me about a time when you felt
proud or ashamed of yourself) while in the second experiment the participants were given
neutral-valence prompts (e.g., tell me something that happened yesterday) (Casasanto &
Dijkstra, 2010). For the first experiment, the participants began the telling of memories earlier
when the direction of movement and valence were congruent than when they were incongruent
(Casasanto & Dijkstra, 2010). The objective of the second experiment was to determine if the
simple motor action of moving marbles in an upward or downward direction can alone cause
people to think more positive or negative thoughts. Their results showed for the second
experiment that when participants moved the marbles downward they recounted more often
negative memories and when they moved the marbles upward, they frequently recounted more
positive memories (2010).
According to the mental metaphor, “positive is up / negative is down” essentially
categorizes upward movements as having a positive valence and downward movements having a
negative valence. But is it safe to assume that we can categorize all seemingly meaningless
actions that are done in an upward direction as having positive valence and all downward actions
as having a negative valence? Casasanto & Dijkstra showed in their study that rolling marbles in
upward and downward directions have a corresponding positive and negative valence (2010). In
section 3, the study I would like to propose is that of the simple task of casually walking in an
upward and downward direction and the corresponding positive and negative valence. Before
deciding on the task that I would like the participants to perform, I wanted to determine whether
the simple act of walking could potentially be classified as “meaningless”, as to not have a direct
effect on emotional valence.
Recently, a study has shown that physical activity rooted in the realms of everyday life
can also display beneficial effects on memory functions (Floel et al., 2010). Thus, actions such as
weekly routine exercises can prove beneficial to one’s mental and physical health. More
specifically, when analyzing the daily function of walking among older and younger adults, the
study showed that memory functions and daily health improved much more significantly among
the older generation (Floel et al., 2010). Thus, for the purposes of the following study, by using a
sample of younger adults from the ages 18-48, the simple task of walking can be considered a
meaningless action.
The study will consist of two experiments. Experiment 1 will consist of two sets of 15
positive and negative valence prompts that will ask the participant to remember and recount
autobiographical memories while walking on a treadmill in either a declined or inclined position.
Experiment 2 will consist of 15 valence-neutral prompts that will ask the participant to remember
and recount autobiographical memories while walking on a treadmill in either a declined or
inclined position. Both experiments will be timed from the start of each prompt for 20 seconds
and will consist of two separate sets of 25 individuals. I predict that walking in an upward or
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The Effect of Motor Action on Emotional Memory
inclined position will in fact trigger a negative valence and walking in downward or declined
position will trigger a positive valence. The angles of the incline and decline position will be so
slight that it will not have in impact on the energy needed to perform the task, but just slight
enough that the participants know they are slanted in one direction or another. The hypothesis
here is to determine that people in fact correlate walking on an incline or upward position, even
though it essentially makes no noticeable difference in the walking task, will associate the
memory from the prompt as having a negative emotional valence and walking on a decline or
downward position will have a positive emotional valence associated with the memory (e.g., it's
all downhill from here; people most likely enjoy walking downward, as slight as it may be, more
so than walking upward). The goal of this study will be to test the validity of the mental
metaphor “positive is up / negative is down” and to possibly propose an extension to the
metaphor.
3.
Proposed Experiments
Ideally, in order to achieve the expected results without any discrepancies, the following
two proposed experiments should as closely mirror the conditions as possible found in a 2010
study by Casasanto & Dijkstra. However, rather than applying the mental metaphor, “positive is
up / negative is down” used in the 2010 study by Casasanto & Dijkstra, the valences and
movements will be reversed. Positive valence prompts will be used for a decline or downward
position and negative valence prompts will be used for an incline or upward position.
Experiment 1
Participants
The participants will be 24 English-speaking undergraduate students enrolled in the
Cognitive Lab for class credit.
Materials
Figure 2: Incline and decline treadmill with LCD screen for prompting
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The Effect of Motor Action on Emotional Memory
Participants will be placed on a treadmill with a computer screen placed in front (Figure
2). A list consisting of 24 memory prompts will be used, half requiring the participant to recount
a memory with positive valence (e.g., Tell me about a time when you felt proud of yourself), and
the other half a memory with negative valence (e.g., Tell me about a time when you felt ashamed
of yourself) (Casasanto & Dijkstra, 2010). All instructions and prompts will be in English, as
well as the memories participants recount. The prompts are provided in Appendix A (2010).
Procedure
Part 1 of the experiment will have the participants placed on a slight incline or upward
position on a treadmill. They will walk on the treadmill for 30 seconds to get themselves in a
comfortable walking state. Participants will be prompted with 6 positive valence questions and 6
negative valence questions. Part 2 of the experiment will have the participants placed on a slight
decline or downward position on a treadmill. They will walk on the treadmill for 30 seconds to
get themselves in a comfortable walking state. Participants will be prompted with 6 positive
valence questions and 6 negative valence questions in each position. For each of 24 trials,
participants will be instructed to use a metronome to keep track of their time (Casasanto &
Dijkstra, 2010). The metronome will be sounded, at 2-s intervals (2010). As soon as the
metronome starts, a prompt will appear on the computer screen instructing the participant to tell
either a positive-valence or negative-valence memory (2010). Participants will then have 30
seconds to retrieve and recount the memory, while walking on the treadmill at the speed of the
metronome.
Each set of prompts will contain an equal number of positive and negative memory
prompts, pseudo-randomly intermixed (Casasanto & Dijkstra, 2010). For half of the trials, the
direction of movement will be congruent with the valence of the memory prompt (downward for
positive prompts, upward for negative prompts), and for the other half direction and valence will
be incongruent. Walking positions and memories will be recorded with an audio–video camera
that will be positioned behind the participant (2010). Afterwards, a trained rater will evaluate the
valence of each memory, not knowing which condition the memory will be recounted in.
(congruent vs. incongruent). The latency from trial onset to the first word of the participant’s
memory will be determined from the audio–video recording, by a coder who will be blind to the
valence of the memory that would follow (Casasanto & Dijkstra, 2010). Trials will be removed
from further analysis if the response latency is greater than 20 seconds, leaving less than 10
seconds to tell the memory (2010).
Experiment 2
Participants
The participants will be a new set of 24 English-speaking undergraduate students enrolled
in the Cognitive Lab for class credit.
Materials
Participants will be placed on a treadmill with a computer screen placed in front (Figure 2
– above). A new list consisting of twenty-four memory prompts will be used, all of which are
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The Effect of Motor Action on Emotional Memory
valence-neutral (e.g., Tell me about an event that happened yesterday) (Casasanto & Dijkstra,
2010). All instructions and prompts will be in English, as will be the memories participants
recount. The prompts are provided in Appendix B (2010).
Procedure
As in Experiment 1, Part 1 of the experiment will have the participants placed on a slight
incline or upward position on a treadmill. They will walk on the treadmill for 30 seconds to get
themselves in a comfortable walking state. Participants will be prompted with 12 valenceneutral questions. Part 2 of the experiment will have the participants placed on a slight decline or
downward position on a treadmill. They will walk on the treadmill for 30 seconds to get
themselves in a comfortable walking state. Participants will be prompted with 12 new valenceneutral questions.
However, participants will not retell memories while walking on the treadmill. Rather,
Experiment 2 will be divided into ‘retrieval’ and ‘retelling’ phases (Casasanto & Dijkstra, 2010).
During the retrieval phase, participants will walk on the treadmill in either a downward or
upward position at the speed of the metronome, while silently reading prompts and retrieving
memories (2010). Prompts will appear one at a time in random order for 20 s each, during which
time participants will be instructed to think about an appropriate memory (2010). During the
retelling phase, participants will see each of the prompts again in the same order, and recount the
memories they will have retrieved aloud (2010). The order of upward and downward positions
will be counterbalanced across participants. Retrieval and retelling phases alternated (2010).
After each block of 12 retrieval prompts, the participant will retell the 12 corresponding
memories for a total of 24 memories that will have been retold, half of which will have been
retrieved while walking on an incline or upward position and the other half while walking on a
decline or downward position.
Walking positions and memories will be recorded with a video camera. Afterwards, the
participants will rate the valence of each memory: positive, negative, neither (indicating neutral
valence), or both (indicating mixed valence) (Casasanto & Dijkstra, 2010). The valence of
memories will also be evaluated by a trained rater and if the participant and rater cannot agree on
valence ratings, those trials will be removed from further analyses.
4.
Expected Results
Experiment 1
If my hypothesis is correct, the participants should begin to retell memories faster during
schema-congruent movements (i.e., upward movements for negative memories and downward
for positive memories) than during schema-incongruent movements. The direction of the incline
should influence how efficiently participants produce their memories, consistent with predictions
of the proposed metaphor theory “positive is down / negative is up”. However, for this first
experiment, it will most likely not be clear as to what extent the congruity effect can arise due to
the process of recounting stories aloud as opposed to retrieving them from memory (Casasanto &
Dijkstra, 2010).
Therefore, Experiment 2 will be needed to determine whether motor action influences
how people talk about emotional memories, or simply how they think about them (2010). In the
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The Effect of Motor Action on Emotional Memory
second experiment, retrieval and retelling will have been separated into different phases of the
experiment. Participants will have been instructed to walk up or down only during the silent
retrieval phase. The goal of Experiment 2 will be to test for a causal influence of motor actions
on the valence of memories (Casasanto & Dijkstra, 2010). That is, can walking on a decline or
downward position cause people to think more positive thoughts?
Experiment 2
Hopefully, the results of the second experiment will show the predicted interaction
between motor action and emotional memory, with movement direction (upward, downward)
and valence (positive, negative) (Casasanto & Dijkstra, 2010). Comparisons will most likely
show that, given the neutral-valence prompts, participants will produce positive memories more
often after walking in a downward position and negative memories after walking in an upward
position. For example, when the participant will be prompted to recount something that
happened in high school, participants should be more likely to recollect an experience like
winning an award after walking in a downward position, but failing a test after walking in
upward position.
Appendix A
Positive- and negative-valence prompts used to elicit memories in Experiment 1 (Casasanto &
Dijkstra, 2010).
Tell me about (positive valence):
. . .a time you ate something delicious.
. . .a time when you received a lot of money.
. . .a time when you won a game or competition.
. . .a time when someone gave you a compliment.
. . .a time when you had a lot of fun.
. . .a time you fell in love with someone.
. . .an important event you experienced.
. . .a time when you received a very nice present.
. . .an event that made you really proud.
. . .a time when you felt really cool.
. . .an exciting event you experienced.
. . .a time you accomplished something important.
Tell me about (negative valence):
. . .a time when something took something valuable from you.
. . .a time when you felt really sick.
. . .a time when you had to do something against your will.
. . .a time when you hurt yourself badly.
. . .an event during which you reprimanded someone.
. . .a time when you were ashamed of yourself.
. . .a frustrating event that you experienced.
. . .a time you lost something.
. . .a sad event that you experienced.
. . .a time when you were very disappointed in yourself.
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The Effect of Motor Action on Emotional Memory
. . .a scary event that you experienced.
. . .an event that disgusted you.
Appendix B
Neutral-valence prompts used to elicit memories in Experiment 2 (Casasanto & Dijkstra, 2010).
Tell me about:
. . .a time when you received an unexpected phone call.
. . .a time when something remarkable happened.
. . .a time when you received a different grade for a test than you expected.
. . .a time when someone came to visit you.
. . .a time when you visited someone.
. . .a time when you went on a trip.
. . .something that happened in elementary school.
. . .something that happened in high school.
. . .something that happened yesterday.
. . .something that happened last Summer.
. . .something that happened before you were school aged.
. . .something that happened while you were playing sports.
. . .something that happened while you were on a train.
. . .something that happened while you were playing outside.
. . .something that happened while you were talking to someone.
. . .something that happened in your house.
. . .an event that involved you and a friend.
. . .an event that involved you and a family member.
. . .an event that happened in the evening.
. . .an event that happened early in the morning.
. . .an event when you were at your neighbor’s.
. . .an event that happened when it was snowing.
. . .an event that had to do with water.
. . .an event that had to do with an animal.
REFERENCES
Tables and Figures:
Wolf, O.T. (2008). Summary of GC effects on different memory forms in rodents and humans.
Acta Psychologica 127, p. 516.
Journal Articles:
Breitenstein, C., Flöel, A., Knecht, S., Krüger, K., Lohmann, H., Mooren, F., Ruscheweyh, R.,
Völker, K., Willemer, C., Winter, B. & Zitzmann, M. (2010). Physical activity and
memory functions: Are neurotrophins and cerebral gray matter volume the missing link?
NeuroImage, 49, 2756-2763.
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The Effect of Motor Action on Emotional Memory
Casasanto, D. (2009). Embodiment of abstract concepts: Good and bad in right- and left-handers.
Journal of Experimental Psychology: General, 138(3), 351–367.
Casassanto D. & Dijkstra K. (2010). Motor action and emotional memory. Cognition, 115, 179185.
Dijkstra, K., Kaschak, M. P., & Zwaan, R. A. (2007). Body posture facilitates retrieval of
autobiographical memories. Cognition, 102, 139–149.
Wolf, O.T. (2008). Summary of GC effects on different memory forms in rodents and humans.
Acta Psychologica 127, 516-531.
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