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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Humor as a Facilitator of Insight Problem Solving</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Sergei Yu. Korovkin (korovkin_su@list.ru)</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Olga S. Nikiforova (weis</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>@mail.ru)</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Matrosova proezd 9</institution>
          ,
          <addr-line>150057 Yaroslavl</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>P.G. Demidov Yaroslavl State University, Department of Psychology</institution>
        </aff>
      </contrib-group>
      <fpage>134</fpage>
      <lpage>139</lpage>
      <abstract>
        <p>Humor can improve a performance of creative problem solving; this phenomenon was repeatedly demonstrated in various studies. However, mechanisms underlying this phenomenon are still unclear. We analyze the possible mechanisms of how humor facilitates creative problem solving. The experiment demonstrates that preliminary humor production facilitates insight problem solving. There is no such an effect in noninsight problems. Humor and stress relief similarly facilitate visual insight problem solving. We suggest that facilitation effect of humor and stress relief is based on the attentional mechanisms of defocusing.</p>
      </abstract>
      <kwd-group>
        <kwd>insight</kwd>
        <kwd>humor</kwd>
        <kwd>problem solving</kwd>
        <kwd>facilitation</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        A few studies have shown that an affective influence
facilitates the creative problem solving and creativity
        <xref ref-type="bibr" rid="ref16 ref26 ref7">(Isen, Daubman, Nowicki, 1987; O’Quin, Derks, 1997;
Ziv, 1976)</xref>
        . The correlation between creative problems
solving and humor is repeatedly confirmed
        <xref ref-type="bibr" rid="ref10 ref11 ref12 ref6">(Gick,
Lockhart, 1995; Korovkin, Nikiforova, 2014; Kozbelt,
Nishioka, 2010; Martin, 2006)</xref>
        . An understanding of
humor, humor production, “sense of humor”, humor as a
heuristic for problem solving are analyzed in the context
of problem solving. A number of theoretical models
consider a humor as a component of creative thinking
        <xref ref-type="bibr" rid="ref14 ref24 ref9">(Koestler, 1964; Mednick, 1962; Torrance, 1966)</xref>
        .
      </p>
      <p>Humor can not be unambiguously attributed to the
affective or cognitive processes; hence definition and
operationalization of humor and its effects on solver are
strongly hindered. To understand the possible mechanisms
of relationship between humor and problem solving
process we should compare their psychological
components. Processes underlying humor production and
understanding are similar to insight problem solving
process in many ways. The list of similarities include
affective and cognitive processes, which, in our opinion,
are related to common nature of humor and insight.</p>
      <p>
        A number of common features can demonstrate
structural and phenomenological similarity of insight and
humor. First, an instantaneous understanding is the basis
of humor and insight
        <xref ref-type="bibr" rid="ref11">(Kozbelt, Nishioka, 2010)</xref>
        .
Traditionally, both humor and insight are associated with
the instantaneous restructuring of representation, which is
necessary to understand a problem or a joke. The study of
relations between humor comprehension and humor
production showed weak correlation
        <xref ref-type="bibr" rid="ref11">(Kozbelt, Nishioka,
2010)</xref>
        . Participants’ appraisal of cartoon funniness is
negatively correlated with “latent content” cartoon
comprehension in humor comprehension tasks. This fact,
according to the authors, supports an insight nature of
humor comprehension. At the same time, results of the
humor production tasks show smaller support for insight
nature of humor production. The instantaneity of problem
and joke grasp is associated with gestalt-principle of
restructuring of representation. However, it was found
that the less time is given to comprehension and appraisal
of joke, the funnier the joke becomes. In other words,
funniness of the joke is negatively correlated with the
effort for its comprehension and explanation. However,
phenomenological instantaneity of insight apparently is
not associated with the speed of problem understanding.
Insight requires long preparatory phase, which is referred
to as an incubation of solution.
      </p>
      <p>
        Second, insight and humor are accompanied by positive
emotions, which are connected with the understanding of
a problem or a joke. The positive emotion can persist even
after an experimenter told a right answer or explained a
joke, when a solver was not able to understand a joke or a
problem. A special genre of creative (insight) problems,
which has a common structure with a verbal joke, is funny
riddles
        <xref ref-type="bibr" rid="ref23">(Smullyan, 1978)</xref>
        . A funny riddle has attributes of
a creative problem and a verbal joke in its structure. If the
problem cannot be solved independently, and an answer
will soon be told, this problem turns into a joke, because
the solver perceives the problem or the answer as
inappropriate and dishonest. Common experience of
humor comprehension and “aha-reaction” has similar
components, such as unexpectedness and astonishment. In
both cases, an emotional state and emotions are positive.
Insight problem solving can be presented as sudden
restructuring of representation, frame shifting or script
switching.
      </p>
      <p>
        Third, problem solving and understanding of jokes are
based on the internal conflict or collision between at least
two cognitive schemes. A text can be interpreted as a
humorous, if two conditions are observed: 1) text is
compatible and actualizes two different scripts; 2) these
scripts are opposite
        <xref ref-type="bibr" rid="ref19 ref3">(Attardo, Raskin, 1991; Raskin,
1985)</xref>
        . The scripts contradiction provides perception of
the text as humor by three basic oppositions: 1) real
unreal situation, 2) expected - abnormal, unexpected
situation, and 3) possible - impossible situation. Verbal
jokes consist of several components. The components or
knowledge resources can be presented as a hierarchy,
which defines variability of jokes. These knowledge
resources are script opposition (SO), logical mechanism
(LM), situation (SI), target (TA), narrative strategy (NS)
and language (LA)
        <xref ref-type="bibr" rid="ref22">(Ruch, Attardo, Raskin, 1993)</xref>
        .
Hypothetically, the components of logical mechanism and
situation are closely related to problem solving. Logical
mechanisms of jokes are a variety of logical errors, such
as straightforward juxtapositions, false analogies,
figureground reversals etc. Scripts of jokes, which are perceived
as comic, often involve limited number of binary
categories: real/unreal, true/false, good/bad, death/life,
obscene/decent, rich/poor, etc. According to
        <xref ref-type="bibr" rid="ref25">Wyer and
Collins (1992)</xref>
        , humor involves simultaneous activation of
two schemes of one situation. However, situation
becomes comic and humorous if a new scheme, which
causes reinterpretation, is perceived as less serious and
less informative. Moreover, the situation is perceived as
more humorous when activation of the alternative scheme
requires more effort and time, i.e. more semantically
distant schemes are perceived as more comic.
      </p>
      <p>
        4. Humor and insight problem solving are likely to
involve a violation of prohibitions. One of the possible
mechanisms of thinking “outside the box” and functional
fixedness overcoming in insight problem solving is
relaxation of constraints in strategies and problem
representation
        <xref ref-type="bibr" rid="ref18 ref8">(Knoblich et al., 1999; Öllinger, Jones,
Knoblich, 2008)</xref>
        . Verbal joke can be perceived as
humorous under the following conditions: 1) two
contradictory ideas must be actualized; 2) the
actualization should be carried out in a playful state in
unserious and secure conditions
        <xref ref-type="bibr" rid="ref2">(Apter, 1982)</xref>
        , 3) content
of jokes must be associated with prohibitions and
restrictions (with threats, norms and taboos)
        <xref ref-type="bibr" rid="ref13 ref15">(McGraw,
Warren, 2010; Minsky, 1984)</xref>
        . These necessary for humor
conditions are also typical for insight problem solving in
some sense. One of the hypothetical mechanisms of
impasse in problem solving is constraint on the possible
solution consideration, which can be overcome by
constraint relaxation
        <xref ref-type="bibr" rid="ref8">(Knoblich et al., 1999)</xref>
        . The content
of funny humor is close to the constraints, taboos and
experience of possible consequences. However, humorous
reaction to possible threat manifests of this threat become
softened and located at the safe distance
        <xref ref-type="bibr" rid="ref13">(McGraw,
Warren, 2010)</xref>
        . Both the content of jokes and frames
collision as insoluble logical paradox can cause a threat.
In this case, humor is an emotional form of thinking
process and logical problem solving cancellation
        <xref ref-type="bibr" rid="ref15">(Minsky,
1984)</xref>
        .
      </p>
      <p>Cognitive mechanisms are associated with the
actualization of contradictory scripts and ways of solving
the two scripts collision. These mechanisms may
contribute to overcome the limitations in problem solving
by variation of a set of heuristics and problem elements.
They can create presetting of remote associations
searching and contribute to “go beyond” in representation
of a problem. The impact of cognitive mechanisms can be
content specific and content nonspecific.</p>
      <p>Affective (affective-regulatory) mechanisms of humor,
in its turn, aim to reduce emotional strain in a situation of
problem solving, as well as contribute to increase the
overall level of resources, which it related with the
efficiency of problem solving.</p>
      <p>In this experiment, we planned to reproduce the effect
of facilitation of insight problem solving by humor and to
answer a number of potential objections to this
phenomenon. First, the standard research paradigm of
humor and affective facilitation studies involves the
presentation of positively stained stimuli (such as video
fragments). In this case, we observe a passive perception
of humor and emotional reaction to a joke. Participants in
positive mood respond more originally and creative; they
set remote associations and solve insight problems more
sufficiently. In this study, we plan to test a reproducibility
of the effect of facilitation provided by participant’s
humor production. Humor production can include
additional cognitive mechanisms of joke generation,
which can affect the problem solving in another way.</p>
      <p>Second, humor facilitates insight problem solving, but
its specificity for insight problem requires verification.
We need to compare how humor affects the insight and
noninsight problem solving. In addition, humor can
differently facilitate different types of representation
formats that can indicate different mechanisms of
facilitation. In this study, we decided to compare textual
format (semantic processes) and visual format (perceptual
processes).</p>
      <p>Third, the humor has a social nature, and insight can be
a phenomenon of social interaction. The situation of the
experiment, which tests the participant’s ability to solve
creative problems, itself, can be a source of frustration,
stress, and excessive motivation, which can reduce an
effectiveness of insight problem solving. Hence,
facilitation may be a consequence of stress relief in the
situation of communication with an experimenter. We
have tried to include the variable of stress relief via a
confidential conversation between the subject and the
experimenter. According to our idea, such a conversation
can reduce motivational and emotional stress in respect of
problem solving as well as a humor.</p>
    </sec>
    <sec id="sec-2">
      <title>Hypothesis</title>
      <p>The hypotheses are:
1. Humor production facilitates insight problem
solving.</p>
      <p>2. The effect of facilitation of insight problem solving is
a result of stress relief in the situation of interaction with
an experimenter.</p>
      <p>3. Humor specifically facilitates insight problems of
various representation format.</p>
    </sec>
    <sec id="sec-3">
      <title>Participants</title>
      <p>The main study sample consists of 36 participants, aged
17 to 45 years (М = 24.3, σ = 6.96). The study involved
university and school students, people with secondary and
higher education. All participated on a voluntary basis,
without additional motivation. The preliminary study
sample consists of 10 participants, aged 20 to 22 years (М
= 20.8, σ = 0.79), to equalize the difficulty of problems.</p>
    </sec>
    <sec id="sec-4">
      <title>Procedure</title>
      <p>Before the experiment, a set of six problems was
established. According to results of the preliminary study
with 10 participants who did not participate in the main
series, we selected four problems with equal time of
solution to control difficulty for the main series of the
experiment. We used two types of problems: insight and
noninsight problems and two types of representation
format: textual and visual format. The textual insight
problem: “Two men play five games of checkers. Each
man wins the even number of games. There are no ties.
How is that possible?” The textual noninsight problem:
“There are five bulbs: red, green, yellow, blue and gold.
How many ways are there to decorate five trees if you
want each tree to wear only one bulb?” The visual insight
problem: “Remove three matches to get only three
triangles”. The visual noninsight problem: “Find the
perimeter of the given figure. The dimensions are 1 cm x
1 cm. Give an answer in square centimeters.”
using the sentence completion test (examples: “Most of
all, I would like…”, “I hope that…”). Two experimental
conditions were equalized by using the same number of
statements for the completion. In the control condition
(neutral condition) participants did not receive stimuli for
emotional priming.</p>
      <p>Each group of participants received four problems to
solve. In each group, the emotional priming
corresponding to the condition was presented before each
problem solving. The duration of problems and priming
tasks performance was pre-equalized. The sequence of
priming tasks and problems was randomly varied. Time of
each problem solving is the efficiency parameter of the
experimental exposure. Statistical analysis was performed
using ANOVA with repeated measures, Mann-Whitney
Utest, Wilcoxon T-test.</p>
    </sec>
    <sec id="sec-5">
      <title>Results</title>
      <p>Participants solved the presented problems completely.
According to the ANOVA with repeated measures, the
factor of problems type significantly affects the time of
solution (F(1, 144) = 12.15, p &lt; .001, ηp2 = .27). Humor
significantly facilitates insight problem solving. There are
significant differences in solution time between insight
and noninsight problems in the stress relief condition
(T(24) = 43, p &lt;.01) and humor production (T(23) = 49, p
&lt;.01), whereas there are no such differences in neutral
condition.
showed no significant differences (U(24) = 212, p = .12).
This means that the stress relief is not enough for the
effect of facilitation.</p>
      <p>In addition to differences between insight and
noninsight problems there are significant differences in
problem solving of various representation formats (F(1,
144) = 36.38, p &lt; .001, ηp2 = .52). Visual problems are
solved quickly in general. The interactions between
problem type and the type of representation was not found
(F(1, 144) = .35, p = .56, ηp2 = .01).</p>
    </sec>
    <sec id="sec-6">
      <title>Discussion</title>
      <p>Thus, humor production can facilitate insight problem
solving. There is no significant effect of humor
production in noninsight problem solving. We found that
participants solve insight problems in humor production
condition significantly faster comparing to neutral
condition. These findings are supported by a) the
aggregate data: humor production condition significantly
different from the neutral condition without reference to
types of representations; and b) visual format of
representation data: humor production condition
significantly different from the neutral condition in
solving of visual insight problems. That means that humor
specifically affects creative problems and this supports the
assumption about the relationship between humor and the
creative process. At the same time, we have not found the
facilitation effect in textual insight problem solving.</p>
      <p>The most previous studies demonstrated that humor
comprehension facilitate insight problems. There was a
lack of information about how participant’s activity in the
humor production influences problem solving. We can
conclude that the production of humor can facilitate
insight problem solving as well as the humor
comprehension. Hypothetically, the mechanisms of
facilitation by the humor production and the humor
comprehension may be common or similar.</p>
      <p>We have received conflicting data on the role of stress
relief in insight problem solving. On the one hand, the
average data show that the stress relief is not sufficient to
affect insight problem solving in general. It may be
interpreted as stress relief is an important component of
humor that can contributes facilitation in a situation of
communication with an experimenter, but simple
relaxation is not enough to improve the efficiency of
problem solving. On the other hand, an independent
review of the data of problem solving with the different
formats of representation demonstrates that stress relief as
well as humor similarly affects problem solving. Neither
stress relief nor humor does not affect the textual insight
problem solving. However, both stress relief and humor
significantly affect the visual insight problem solving. It
means that stress relief and humor affect insight problems
the same way. Relaxation (or stress relief under the
experimental conditions) can be an important component
of the facilitation, particularly, of visual insight problems.</p>
      <p>We found that humor specifically facilitates insight
problems of the various formats of representation. Humor
significantly facilitates only visual insight problem
solving. There is no facilitation effect in the textual
insight problem. As mentioned above, the stress relief
condition demonstrates the same pattern.</p>
      <p>These results can be interpreted from the different
points of view. First, we assumed that humor as well as
stress relief facilitate problem solving via a changes in
social interaction between participant and experimenter.
Relaxation, the tension reducing, and the motivation
decreasing must affect insight problems in general.
However, we can see clearly that facilitation effect has
representational specificity, which is difficult to interpret
solely by social interaction.</p>
      <p>
        Second, we can use the working memory model to
understand how different representations of problems are
related with independent variables (humor production and
stress relief tasks). The problems’ formats of
representation used in the experiment are correlated with
the slave systems of working memory
        <xref ref-type="bibr" rid="ref4">(Baddeley, Hitch,
1974)</xref>
        . It can be assumed that the visual problems are
related to the visuospatial sketchpad, which is a storage of
visual and spatial information in working memory.
Likewise, the textual problems are related to the
phonological loop, which is a storage of auditory and
articulatory information. The experimental impact was
performed in textual format (questions and a sentence
completion tasks). However, this model can predict
inhibition effects of parallel processing of information in
the same storage, but it is hard to explain facilitation
effects via the storage specificity. Moreover, the generally
accepted data that decrease of central executive functions
is associated with insight problem solving cannot shed
some light on the mechanisms of visual and textual
specificity of the insight problems.
      </p>
      <p>Third, one of the possible interpretations of the
facilitation effect is arousal increase. Arousal can provide
an additional cognitive resource for problem solving.
However, arousal should have a nonspecific impact on
problem solving. It is not clear why insight problems are
more sensitive to arousal than noninsight problems as
well as why visual insight problems are more sensitive to
arousal than textual insight problems.</p>
      <p>
        Fourth, we assume that a crucial difference between
facilitation effect of humor and stress relief is based on
the attentional mechanisms. Facilitation effect appears to
be associated with low-level perceptual processes,
because the effect is significant only in the visual insight
problem. Insight problems are related to perceptual
processes of gestalt restructuring
        <xref ref-type="bibr" rid="ref5">(Duncker, 1945)</xref>
        and
chunk decomposition
        <xref ref-type="bibr" rid="ref17">(Ohlsson, 1992)</xref>
        which are most
often referred to insight problem solving. Perceptual
mechanisms can influence problem solving indirectly, for
example, through the processes of attention. Humor and
stress relief can reduce the concentration of attention
        <xref ref-type="bibr" rid="ref21">(Rowe, Hirsh &amp; Anderson, 2007)</xref>
        , provide a “peripheral
focus” and make perceptive and thought patterns instable.
Humor and relaxation reduce a concentration of voluntary
attention as the executive function of working memory.
These assumptions are confirmed by data showing that
participants with low working memory capacity are more
sensitive to background hints
        <xref ref-type="bibr" rid="ref1">(Ansburg &amp; Hill, 2003)</xref>
        and
patients with lesions of the prefrontal cortex more
sufficient in insight problem solving
        <xref ref-type="bibr" rid="ref20">(Reverberi et al.,
2005)</xref>
        .
      </p>
      <p>Finally, we have to notice some limitations of the
research. In our experiment, we used only two insight
problems. The visual insight problem can be solved via
defocusing of the visual representation of triangles
presented to the participants. Nevertheless, the textual
insight problem used in the experiment do not have key
markers of representation in text that should be defocused.
This problem is based on the biases of mental models of
the proposed situation. Thus, the insight problems used in
our research have different formats of representation and
different structures.</p>
      <p>We can conclude that our experiment demonstrated
that humor production facilitates insight problem solving.
Humor and stress relief similarly affects insight problem
solving which allows us to assume the common or similar
nature of facilitation mechanisms. Humor specifically
facilitates visual insight problem solving. We suggest that
facilitation effect of humor and stress relief is based on
the attentional mechanisms of defocusing. However, the
specific facilitation of the representational format and the
problem structure in insight problem solving requires
further investigation.</p>
    </sec>
    <sec id="sec-7">
      <title>Acknowledgments</title>
      <p>This work is supported by Russian Foundation for
Basic Research (grant 15-06-07899а) and President grant
MK-3877.2015.6.</p>
    </sec>
  </body>
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