Social Cognition, Vol. 29, No. 6, 2011, pp. 683–698
McMahon et al.
Driven to Distraction
Driven to Distraction:
The Impact of Distracter Type on
Unconscious Decision Making
Kibby McMahon, Betsy Sparrow, Ljubica Chatman, and Travis Riddle
Columbia University
While there is a variety of wonderful ways to take a break from work, is
there a type of distraction that is actually more productive? Studies on the
deliberation-without-attention effect (Dijksterhuis, 2004; Dijksterhuis, Bos,
Nordgren, & Van Baaren, 2006) show that a period of distraction while
making complex decisions can actually lead to better decisions than a period of conscious deliberation. Although there are a number of activities
that will distract participants from decision-making tasks, we investigated
if certain types of distracter tasks are better for demonstrating the deliberation-without-attention effect. Since most people realistically take a break
with undemanding forms of activity, we hypothesized that undemanding
distracter tasks will yield the best results. In Experiment 1, participants
were given a choice between four different cars but before they made their
decision they instructed (1) to think consciously about the choices, (2) listen to their own music with a portable digital music player, (3) solve an
anagram puzzle, (4) solve a word search puzzle, or (5) just make a decision
immediately. In Experiment 2, participants were given a choice among four
different applicants for a hypothetical graduate school program and were
instructed (1) to think consciously about the applicants, (2) to engage in a
listening task with music, or (3) to just listen to the music. As predicted, the
participants who were distracted with the easier tasks (listening to music
and word search puzzles) made the best decision significantly more often than conscious thinkers and even outperformed participants distracted
with more difficult tasks.
Most of us have experienced mulling over a difficult decision or problem that appeared impossible to solve when the answer just came to us only after putting
the matter aside for a while. Taking a break from tasks like complex decisions or
insight problems has shown to be actually productive for solving them (Beeftink,
Address correspondence to Kibby McMahon, 406 Schermerhorn Hall, 1190 Amsterdam Avenue
MC 5501, New York, NY 10027. Email: kibbymcmahon@gmail.com
© 2011 Guilford Publications, Inc.
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Van Eerde, & Rutte, 2008; Dijksterhuis & Nordgren, 2006; Paulus, Nakui, Putman,
& Brown, 2006; Smith, 1995; Wallas, 1926), but are all forms of distraction created
equal? When you take a break for a few minutes, it feels very different to relax
with some music than to start busying yourself with something else on your to-do
list. In this article we examine types of distracters and their impact on decision
making.
Dijksterhuis and colleagues pioneered the work on what they call the deliberation-without-attention effect (Dijksterhuis, 2004; Dijksterhuis, Bos, Nordgren, &
Van Baaren, 2006), which leads to improved decision making for complex decisions. Specifically, they have shown that when participants are distracted from a
decision-making task involving a lot of pertinent information, they are more likely
to make the best decision than if they thought about it consciously. The common
paradigm Dijksterhuis et al. use consists of a pre-acquisition phase, followed by an
acquisition phase, an incubation period, and then the actual decision. In the preacquisition phase, subjects are informed that they will read over the descriptions
of four different items and will have to choose the best one later in the study. After
reading over the descriptions of four different items, participants are assigned to a
“conscious thought” or an “unconscious thought” condition. Participants assigned
to the conscious thought condition are told to carefully consider the options before
making the choice. Those in the unconscious thought condition engage in an unrelated task before making their choice. Once the incubation period is finished, all
subjects indicate which item they think is best out of all four. Results consistently
show that participants in the unconscious thought condition make decisions or
judgments that favor the best choice more often than participants in the conscious
condition.
While there is evidence for the benefits of distraction, the quality of distraction
must be taken into account. Requiring participants to engage in another difficult
task in addition to the decision-making task adds cognitive demands (Hart, 1986;
Norman & Bobrow, 1975), which can lead to information overload that actually
hinders processing (Chewning & Harrell, 1990; Huber, 1985; Speier, Valacich, &
Vessey, 1999). Within a review of attention allocation and task demands, Kahneman (1973) mentions that when attending to different tasks, the type of one task
can influence the performance on the other. Working on two tasks can create attentional conflict, which can be either structural interference if the content of the two
tasks are similar, or capacity interference if the task difficulties compete for cognitive
resources. The Distraction-Conflict Theory (Baron, 1986) argues that if a distracting task is difficult enough to create such an attentional conflict, the arousal and
information overload will inhibit performance on complex tasks. Thus the type
and difficulty of a distracting task would have an influence on the performance
of a concurrent decision-making task. These theories do not directly address the
issue of a separate unconscious decision-making process. However, it has been
argued that conscious and unconscious processes are not completely independent
systems but instead have an interactive relationship (Evans, 2006; Kahneman &
Fredrick, 2002; Reber, 1993). Devoting conscious resources to an unrelated task allows unconscious thought to process a different task, but it might not be so simple
to claim that all forms of distraction yield the same results; what we devote our
attention to might influence how the unconscious processes perform.
To induce unconscious thought, Dijksterhuis and colleagues (Dijksterhuis, 2004;
Dijksterhuis et al., 2006) have used a myriad of distracter tasks such as word search,
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685
anagrams, and n-back tasks. All of these tasks seem to accomplish the goal of distracting participants from the decision-making task enough to let unconscious
thought processing arrive at the best decision. There has not been any report that
the differences in the tasks have an impact on the deliberation-without-attention
effect even though they require slightly different cognitive processes to solve. To
solve a word search puzzle, one must hunt through a matrix of letters to find a
target word. Priming the category of a target word-within–a-word search has no
significant impact on performance, suggesting that word search puzzles are visual
perceptual tasks that do not require any semantic activation of the target word
(Karlin & Bower, 1976). However, anagram puzzles consist of a list of scrambled
words that participants must identify and spell correctly (i.e., the correct answer to
“lisa” is “sail”). There is some evidence that solving anagram puzzles activates a
deeper level of processing (Rajaram & Roediger, 1993; Srinivas & Roediger, 1990).
These two puzzles can both successfully occupy conscious resources, but it is unclear if the difference in their cognitive demands would influence the concurrent
unconscious processes.
In addition to a lack of research into the previously used distracter tasks, there
has not been any work demonstrating that the deliberation-without-attention effect will hold for more ecologically valid distracters. One of the most ubiquitous
distracters in daily life are portable music players. As twentieth-century English
conductor Sir Thomas Beecham astutely claimed, “The function of music is to release us from the tyranny of conscious thought.” Rauscher, Shaw, and Ky (1993)
came across an interesting finding in their studies that suggested classical music
(specifically Mozart pieces) temporarily enhance spatial reasoning performance.
This was dubbed the “Mozart Effect” and sparked new interest in how listening
to music can improve the performance of various cognitive processes (Fairfield &
Cornoldi, 2007; Lesiuk & Teresa, 2010; Mammarella, Fairfield, & Cornoldi, 2007;
Rauscher et al., 1993; Rideout, Dougherty, & Wernert, 1998). An interesting pilot
study by Caldwell and Riby (2007) explored how listening to a subject’s preferred
music genre affects the processing of novel information. Rock and classical musicians listened to either classical or rock music while completing an oddball task, an
attention exercise in which subjects have to pick out when a new stimulus appears
on a computer screen. Their event-related potentials suggested that conscious processes like working memory were not as strongly deployed to the oddball task if
the subject listened to their preferred music genre. If listening to music has such
a notable influence on cognitive abilities and attention, it is worth exploring how
well it can apply to an unconscious decision-making paradigm, especially since it
is such a popular form of distraction.
In these experiments, we compared the efficacies of the different distracter tasks
to see if the type or difficulty of the distraction has any influence on unconscious
decision making. We predicted that we would replicate Dijksterhuis’ results in
the overall comparison of conscious thought and unconscious thought conditions
for difficult decisions. Furthermore, we examined the nuances of different unconscious thought conditions in Experiment 1. Taking into account the previously
mentioned literature on task difficulty and attentional conflict, we predicted that
undemanding tasks such as listening to music and solving word search puzzles
would lead to higher performance on the complex decision-making task than the
more challenging anagram puzzles. In Experiment 2, we attempted to replicate the
deliberation-without-without attention effect with music, except within a social
686McMahon et al.
decision-making task. We also explored the influence of different levels of difficulty, or cognitive load, within the same type of distracter task. We predicted that
an easier and less challenging distracter task would lead to better unconscious
decision-making performance.
Experiment 1
Method
Participants and Design. Seventy-four Columbia University students were recruited through the introductory psychology courses or through flyers posted
around campus and compensated with course credit or $5. All participants were
randomly assigned one of five conditions: an immediate decision condition (n =
15), a conscious thought condition (n = 15), a word search condition (n = 14), a
portable music or iPod condition (n = 15), and an anagram condition (n = 15). The
latter three conditions all fall under the unconscious thought category, but use different types of distraction.
Distracter Task Difficulty. Subjective ratings of cognitive load and working memory tasks have been used as a reliable measure of difficulty (Bratfisch, Borg, & Dornic, 1972; Paas, Van Merriënboer & Adam, 1994). The distracter tasks were judged
for their relative difficulty with 17 separate participants from the same pool of
Columbia University students. The word search, anagram, and iPod tasks were
completed by each participant in random order and then rated for level of difficulty on a scale of 1 (not difficult) to 7 (very difficult). A repeated measures ANOVA
determined a significant difference in difficulty among the distracter tasks, F(2,17)
= 42.08, p < .01. Post hoc pair-wise comparisons using Bonferroni correction revealed that anagram puzzles (M = 5.18, SE = 1.43) were rated as significantly more
difficult than the word search task (M = 3.94, SE = 1.64) at p< .04 and the iPod-listening task (M = 1.35, SE = .86) at p < .01. The word search task was also considered
significantly more difficult than the iPod-listening at p < .001
Procedure
Participants were seated at a lab computer that used the experimental programming software Medialab (Jarvis, 2004). All participants were informed that they
would be presented with descriptions of four different cars and would have to
choose the car that is the best overall. As in Dijksterhuis’ (2004) study 2, participants were then presented with the description of the cars for 10 seconds each.
Each car had the same 12 attributes: handling, gas mileage, impact on the environment, legroom, quality of sound system, quality of service, difficulty to shift gears,
trunk size, age of car, choice in color, sunroof, and cup holders. These attributes
could either be positive (e.g.,“The Hatsdun has good gas mileage”) or negative
(e.g., “The Nabusi has bad gas mileage”). The best car, the Hatsdun, had 75% positive attributes, the medium cars had 50% positive attributes, and the worst car had
25% positive attributes. Even though this proportion of positive and negative attributes makes the Hatsdun the overall best choice, we took into account the possibility that some car attributes are more important than others. The distribution of
Driven to Distraction
687
TABLE 1. The Valence of the Attributes for Each Car
Gas Mileage
Handling
Environment
Sound System
Service
Shifting Gears
Trunk Size
Legroom
New/Old
Colors
Sunroof
Cup Holders
The Hatsdun
The Nabusi
The Kaiwa
The Dasuka
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positive and negative attributes of each car was based on Rey, Goldstein, and Perruchet’s (2009) attribute weighting. His survey results provide a mean value of influence for each type attribute according to how important it is. When an attribute
is positive (e.g., “The Hatsdun has good mileage”) the mean value of influence
score is positive, and when the attribute is negative (e.g., “The Nabusi has poor
handling”) the mean value of influence is negative. A mean evaluation score for
each car was calculated from averaging the values of all the attributes. The higher
the mean evaluation score, the better the car is. Based on Rey’s attribute values,
our version of the Hatsdun had a mean evaluation score of 5.9, the Kaiwa had a
score of .5, the Dasuka had a score of -1.1, and the Nabusi had the lowest score of
-5.4. The positive and negative attribute distribution is displayed in Table 1.
After participants read the descriptions of the four cars, they were assigned to
the immediate, the conscious thought, the iPod, the anagram, or the word search
condition. In the immediate condition, participants chose the best car right after
they read the four descriptions. In the conscious thought condition, participants
were told to spend 3 minutes carefully considering the four different cars before
making their decision. The iPod, anagram, and word search conditions are all different forms of unconscious thought conditions. For the iPod condition, they were
told to listen to any song they liked on their portable music player with headphones for 3 minutes (all participants were asked to bring in a portable music
player in case they were randomized to this condition). In the word search and
anagram conditions, participants spent 3 minutes solving the assigned puzzle.
Once the 3-minute conscious thinking or distraction period was over, participants indicated which car they thought was the best overall out of all four in multiple choice format. They were then debriefed, compensated, and dismissed.
Results and Discussion
The percentages of participants in each condition who chose the best car, the Hatsdun, are displayed in Figure 1. We used a generalized linear model to analyze
this binary data. As we expected, we found an overall significant main effect of
thought, Wald chi-square = 13.29, df = 4, p < .02, indicating that some types of
688McMahon et al.
Figure 1. Percentages shown are based on the proportion of subjects who chose the Hatsdun,
the best choice, to the total number of subjects in each condition.
thought condition performed better than others. Pair-wise comparisons revealed
that the word search condition significantly outperformed the conscious thought
condition (M = -.47, SE = .161, Z score= -2.9, df = 1, p < .01), as did the iPod condition (M = -.45, SE = .166, Z score = -2.7, df = 1, p < .01). The participants in the
anagram condition did poorly and did not differ significantly from the conscious
condition (M = .07, SE = .154, Z score = .45, df =1, p =.67).
We also noted that participants in the immediate choice condition did significantly worse than the word search condition (M = -.33, SE = .170, Z score = -1.9, df
= 1, p < .05), and marginally worse than the iPod condition (M = -.31, SE = .175, Z
score = -1.77, df = 1, p = .07). The immediate choice condition did not significantly
differ from the conscious thought (M = .13, SE = .170, Z score = .76, df = 1, p = .43) or
the anagram condition (M = .20, SE = .163, Z score = 1.23, df = 1, p = .22). This comparison provides additional evidence for the claim that the improved performance
of unconscious thought conditions is not due to using an on-line judgment made
during the acquisition phase. Since the immediate condition performance lies in
between the performances of unconscious and conscious thought, we are lead to
believe that it demonstrates the relative effectiveness of each kind of thought.
These results suggest that listening to music is an effective type of distraction
that can lead to improved decision making. Both the iPod and word search conditions allowed subjects to take a break from the decision-making task with an
activity stimulating enough to capture their attention. We were surprised at how
poorly the anagram condition performed considering its success in previous work
(e.g., Dijksterhuis, 2004). While running the experiment, we noticed a difference
in students’ reactions to the distracter tasks. People in the word search and iPod
conditions looked engaged in their tasks and nothing seemed out of the ordinary.
After the incubation period in the anagram condition, however, most of the participants appeared flustered and discouraged. Some of them hesitantly handed in
their anagram sheets, apologizing for not doing that well.
An interesting finding emerged when we explored the type of errors that conscious thinkers were making instead of choosing the Hatsdun. Further analyses
revealed that those in the underperforming conditions tended to select the first
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Figure 2. Percentage of participants who chose the Kaiwa, the first car, out of all the
participants in each thought condition.
car presented, the Kaiwa. Percentages of car one (the Kaiwa) choices are shown in
Figure 2. The generalized linear model reveals no overall significance of thought
condition, Wald chi-square = 3.78, df =4, p = .44, but pair-wise comparisons reveal
that the conscious (M = -.40, SE = .126, Z score = -3.17, df = 1, p < .01), immediate
(M= -.33, SE = .122, Z score = 2.7, df = 1, p < .01), and anagram (M= -.33, SE = .122, Z
score = 2.7, df = 1, p < .01) conditions chose Kaiwa significantly more than the iPod
condition. The conscious condition also chose Kaiwa significantly more than the
word search condition (M= -.33, SE = .142, Z score = 2.32, df = 1, p < .01).
The Kaiwa does not have anything that would make it stand out from the other
cars, especially since it has negative attributes within the most important characteristics. The only aspect worth noting of the Kaiwa is that it is the first car presented in the acquisition phase. Its popularity may be attributed to the primacy
effect, a serial order effect that biases judgment toward the first item presented in
a sequence (Deese & Kaufman, 1957). Heuristics reduce complex decision-making
and reasoning tasks into fast, automatic judgments based on previous experience
(Tversky & Kahneman, 1974), and streamline complex judgment and reasoning
processes by making use of a fewer, more select number of available cues (Shah &
Oppenheimer, 2008). In this way, deliberative conscious thought could exacerbate
the tendency to give some attributes too much weight within the decision, as Dijksterhuis and Nordgren (2006) describe in the unconscious thought theory. In Experiment 2, we explored these heuristic-consistent errors as a secondary concern.
Experiment 2
The second experiment further replicates the deliberation-without-attention effect with music, but within a social decision-making task. Listening to portable
music proved to be an effective distracter that is not only ecologically valid, but
also leaves flexibility for different engagement and attention manipulations. We
compared conscious thought to both high and low cognitive load music listening
conditions to see if the levels of difficulty of the distracter task had any influence
690McMahon et al.
on the deliberation-without-attention effect. In addition, we also investigated if
there were any consistent mistakes within incorrect responses.
Method
Participants and Design. Seventy-two Columbia University students participated
in this experiment for course credit or $5. All participants were taken from the
Columbia undergraduate population to increase the influence of in-group bias for
other Columbia students. Participants were randomly assigned to one of three
conditions: conscious thought condition (n = 24), easy iPod condition (n = 24), and
difficult iPod condition (n = 24).
Distracter Task Difficulty. As in Experiment 1, these two iPod (or unconscious
thought) tasks were rated on a 7-point difficulty scale by the same participants
who rated the other distracters, plus an additional Columbia University student
(for a total of 18 raters). A repeated measures ANOVA determined a significant
difference between among the tasks, F(1, 18) = 29.97, p < 0.01 (Mdifficult = 3.72, SE
= 1.87; Measy = 1.33, SE = .08). Subjects found that an added listening exercise in
the hard iPod condition provided a more difficult task than the condition in which
they could listen to music with no other demands in the easy iPod condition.
Procedure. Participants were seated at a computer that used the experimental
programming software Medialab (Jarvis, 2004). Participants were told that they
are in charge of admissions to a hypothetical graduate school that judges applicants based on 12 attributes: Graduate Record Examination (GRE) percentile, undergraduate university, grade point average (GPA), quality of recommendations,
prestige of the recommenders, interest in your particular institution, ability to meet
deadlines, honors, relevance of undergraduate major, ability to contribute ideas to
the program, email address, and amount of work experience. Participants were
then given full descriptions for four different applicants with all the attributes of
each applicant presented on the screen for 14 seconds each in randomized order.
Much like in the car context, these attributes could either be positive (e.g., “Rachel is good at meeting deadlines”) or negative (e.g., “Victoria is bad at meeting
deadlines”). Rachel, the best applicant, had 75% positive attributes, Victoria was
considered the worst with 25% positive attributes, and the two medium applicants
both had 50% positive attributes. We based the distribution and relative attribute
weighting on the results of pretesting. These initial rankings were confirmed by
ranking scores the participants gave to each attribute (see Table 2).
Once the four applicant descriptions were presented, participants were randomly assigned to one of three conditions. In the conscious thought condition, they
were told to spend the following 3 minutes carefully considering the applicants.
The easy iPod condition was a kind of low load task in which the participants were
distracted with no performance or cognitive demands. The instructions they were
given were: “you will take a break of three minutes. Please choose a song with
lyrics on your iPod by any band or artist you like.” In the difficult iPod condition,
we wanted to use the same type of distraction except with an added motivation
to increase attention to the music. The participants were told, “You will spend the
next three minutes listening carefully to a song with lyrics on your iPod by any
band or artist you like. First, write down the name of the song in the box provided
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TABLE 2. The Valence of the Attributes for Each Applicant
Grade Point Average
Recommendations
University
Graduate Record Examination
Work Experience
Ideas
Interest in Program
Honors
Prestige of Recommenders
Deadlines
Major
Email Address
Rachel
Victoria
James
Peter
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and as you listen, remember and write down every word that begins or ends with
the letter ‘T.’ Please list as many words as you can since your performance will be
scored.”
After the 3-minute incubation period, participants were shown the applicant
descriptions for 1 second each as a quick review to prevent the participants from
forgetting which applicant was which. Then they had to choose the overall best
applicant in a randomized multiple-choice format. Afterward they filled out an
affect questionnaire and rated on a 7-point scale the levels of enthusiasm, stress,
interest, boredom, and alertness they felt during the experiment. They then ranked
the 12 application attributes in descending order of relative importance. Participants were then debriefed, compensated, and dismissed.
Results and Discussion
For each condition, the percentages of participants who chose the best applicant
(Rachel) are displayed in Figure 3. We used a generalized linear model to assess
the probability of selecting Rachel as a function of the thought condition participants were randomly assigned to. We found a marginally significant main effect
of thought, Wald chi-square = 5.521, df = 2, p = .063, but pair-wise comparisons
revealed that the easy iPod condition performed significantly better than the conscious thought condition (M = -.33, SE = .136, Z score = -2.43, df =1, p < .01). The
difficult iPod condition marginally outperformed the conscious condition (M =
-.25, SE = .138, Z score = -1.81, df = 1, p = .06). As we hypothesized, both kinds of
distraction, easy and difficult, outperformed the conscious thought condition, but
only the easy iPod condition performed well enough to yield a significant difference. A comparison between the two iPod conditions did not yield a significant
difference (M = .08, SE = .142, Z score = .56, df = 1, p = .56). When participants take
a break with their own choice of music, their decisions reflect the performance of
unconscious thought when making complex decisions. This suggests that the deliberation-without-attention effect could be replicated in more ecologically valid
692McMahon et al.
Figure 3. Percentage of participants who chose Rachel, the best applicant, of all the
participants in each thought condition.
methods of distraction. Although participants in both iPod conditions made better
decisions than conscious thinkers, a demand for more concentration on the distracter task in the hard iPod condition impaired the unconscious decision making.
The effect was not as strong as with the anagram condition in the previous experiment, but the difficulty ratings suggest that the listening task was not as challenging as an anagram puzzle. However, as in Experiment 1, the participants who were
distracted with the easier task made the best decision most often.
Taking into consideration the pattern of incorrect decisions in Experiment 1, we
looked at which erroneous choice was the most popular in Experiment 2 and if
there was any implication of heuristic use. “James” was the less qualified applicant
and was only distinguished by his status as an alumnus of Columbia University.
Since all of the participants were members of the Columbia University community,
it can be argued that the decision making of the conscious thinkers were biased by
the in-group bias; that is, the tendency to favor members within ones own social
categories (Tajfel, 1970). An analysis of the number of people who chose James
as a function of type of thought condition revealed that there was a marginally
significant overall main effect of thought, Wald chi-square = 5.388, df = 2, p = .07,
but participants in the conscious thought condition chose James significantly more
often than those in the easy iPod condition (M = .33, SE = .131, Z score = 2.52, df =
1, p < .01). The percentages of participants who chose James and the percentages
of the participants who chose either of the other two incorrect responses within
each thought condition are displayed in Figure 4. These results are hard to interpret considering the three conditions had unequal numbers of participants who
made an incorrect decision. However, within the incorrect decisions, there was a
trend toward choosing James more prominently in the conscious and difficult iPod
conditions. More exploration on heuristics and the deliberation-without-attention
effect would be necessary to draw any definite conclusions.
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Figure 4. Percentage of participants who chose James, the Columbia applicant, compared
to the percentage who chose either Peter or Victoria, of all participants in each thought
condition.
Affect and Attribute Ratings
The post-study questionnaires measured explicit reports of emotion and value
placed on the respective 12 applicant attributes. We ran one-way ANOVA analyses to compare the effect of thought condition on each affect rating and only the
Alertness rating was significant, F (2)= 4.94, p < .02. A pair-wise comparison revealed that the mean rating of Alertness in the difficult iPod condition (M = 1.75,
SE = .193) was significantly lower than in the conscious thought condition (M =
2.54, SE = .193). The participants in the easy iPod condition lay in between (M =
2.17, SE = .193) the two other conditions, feeling slightly less alert than conscious
thinkers but more than the difficult iPod participants. Although this is only based
on self-report, these results suggest that alertness during the experiment does not
definitively account for the differences in decision-making performance among
the conditions. It is possible that too much or too little attentiveness can impair
decision making, but the effect is too small to be determined as the mechanism of
deliberation-without-attention effect.
Each participant ranked each of the 12 attributes from 1 (most important) to 12
(least important) based on how influential the attributes were for assessing the
overall quality of the applicants. The means for university ratings are displayed
in Table 3; the lower the mean ranking score, the more important the attribute is
considered to be within an application. There was no significant effect of thought
condition on any of the rankings, suggesting that there are no major differences
in the explicit decision-making strategies the participants used to compare the applicants. However, we used these mean ranking scores to calculate the individual
applicants’ mean evaluation score. Rachel had a mean evaluation score of 2.84,
Victoria had a score of -2.74, Peter had a score of 1.01, and James had a score of .21.
Therefore, Rachel was confirmed as the best choice even taking into account that
some attributes of an application are considered more important than others.
694McMahon et al.
TABLE 3. The Mean Ranking Scores of Each Application Attribute
Attribute
Mean
Standard Deviation
Grade Point Average
Recommendations
University
Graduate Record Examination
Work Experience
3.06
4.65
5.24
5.24
5.46
2.28
2.72
3.37
2.83
3.17
Ideas to Contribute
Interest in Program
Honors
Prestige of Recommenders
Ability to Meet Deadlines
Relevance of Major
Email Address
5.85
6.44
7.01
7.19
7.46
8.75
11.56
3.16
3.08
2.19
2.75
2.82
2.73
1.63
General Discussion
We were interested in refining the idea of a distracter task within a deliberationwithout-attention context and determining which distractions are the most useful
in making complex decisions unconsciously. The first experiment was intended to
compare different types of distracters, especially to see if a popular form of distraction, listening to portable music, can yield the same unconscious thought performance as other known tasks. The results of the experiment suggest that distracters
such as word searches and iPods lead to making better complex decisions than
thinking consciously about the decision. However, it was surprising how poorly
people in the anagram condition performed, as if the pressure the subjects felt to
do the anagram was enough to dampen unconscious thought’s abilities. We isolated this factor of task difficulty in the second experiment by providing different
levels of difficulty to the participants while keeping the distracter task constant.
As we predicted, all the subjects who were distracted with music performed well
on the decision-making task, but only the subjects who listened to music with no
added cognitive demands made the best choice significantly more than conscious
thinkers. The type or level of difficulty that drives these effects is still unclear,
but the consistent high performance of participants with easy tasks suggests that
distractions with the least amount of cognitive demands are the optimal choice for
the deliberation-without-attention effect. Further work would have to determine
what type of distracter or the threshold of distracter difficulty would completely
obstruct unconscious processing.
If you recall a time when you took a break from a difficult situation, work assignment, or decision, most likely you engaged yourself in your favorite mindless
form of procrastination. In these studies, all the unconscious thought conditions
included an incubation period, but only the easy tasks of word searches and passive music listening really simulated how people take a real break. The feeling of
relaxation and low vigilance during these easy tasks could account for the high
decision-making performance. On the other hand, Yerkes & Dodson (1908) and
Zajonc’s (1965) work on social facilitation both provide evidence that arousal over
a certain threshold can impede performance on challenging tasks. Therefore, the
Driven to Distraction
695
added pressure that the anagram and difficult iPod conditions could have elevated subjects to a level of arousal that impaired their performance on the difficult
decision-making task. Conscious thought also has that added pressure of concentrating on the decision-making task, which would further impede performance.
The issue of affect in general has been raised as a confounding factor since people
listening to music may feel happier during the experiment. There is some evidence
that positive affect can improve performances on cognitive tasks such a decision
making and creative problem solving (Isen, Daubman, & Nowicki, 1987; Isen &
Means, 1983). To check for this, we had subjects report their levels of enthusiasm,
alertness, boredom, stress, and interest during the experiment. None of the measures showed a significant effect of positive affect among the thought conditions,
so we ruled this out as a possibility. The participants’ subjective ratings of alertness do not support the argument that high arousal or attentiveness leads to lower
performance. Perhaps physiological measures can more clearly point to an effect
of arousal, but our lack of evidence leads us to believe that our data is less affected
by arousal and more a result of the different cognitive demands.
An exploratory look into the incorrect decisions revealed a trend toward the
heuristic-consistent choice. The Kaiwa car and James were choices that were operationally not the best option, but were appealing to those making decisions based
on shortcuts like the order of item presentation or the preference toward members
of your own social group. There is evidence that when people feel pressured to
complete a task and if the task is difficult, their attention resources are depleted
and they default to biased responses (Chaiken & Maheswaran, 1994; Kunda, 1990).
A series of studies by Pelham and Neter (1995) found an interaction with task difficulty and motivation on making heuristic-consistent errors. When subjects were
motivated to answer difficult versions of decision-making tasks, they were more
likely to rely on the heuristics and make inaccurate judgments than if they were
unmotivated within easy versions of the task. Although the heuristics data from
our studies are far from conclusive, it is interesting to note that the incorrect decisions of the participants in the difficult distracter and conscious conditions tend to
be biased, a typical result of restricted attentional resources. Thinking consciously
about a complex decision or engaging in difficult distracters may tax attention
resources enough to reduce decision-making accuracy. These conditions lead to information overload, which negatively impacts task performance according to the
aforementioned capacity interference (Kahneman, 1973) and Distraction-Conflict
Theory (Baron, 1986). It questions the perspective that distractions activate only
unconscious thought and deliberation activates only conscious thought. Instead,
there is enough overlap within the two systems that the difficulty of the task during incubation periods can influence the concurrent decision-making process.
Growing evidence for implicit processes within the field of working memory
further supports the interaction of unconscious and conscious processes. Given
that conscious attention is so limited, current working memory models claim that
consciousness is useful for processing stimuli input and activating the unconscious
networks to process this information (Baars, 2002, 2003; Baars & Ave, 1997). Recent
dual-process theories have proposed that we can make automatic judgments and
decisions, but conscious thought can monitor and modify their effect (Chaiken,
Liberman, & Eagly, 1989; Evans, 2006). These theories support the idea that explicit and implicit processes often work together instead of exist as two distinct
systems. The successful unconscious thought paradigms first require subjects to
696McMahon et al.
attend to the necessary information on the four items before distraction can allow
for the unconscious working memory to process the decision. Attending to yet
another task might overwhelm the working memory and deplete both conscious
and unconscious resources. Our results suggest that the best way to facilitate the
deliberation-without-attention effect is to consciously attend to all of the available
information, then engage in a distracter task that is low in cognitive load and does
not require a lot of working memory or attention resources.
Conclusion and Implications for Further Research
Distracter tasks that are low in difficulty are shown to be the most successful in
demonstrating the deliberation-without-attention effect. Further replications of
this effect should take the quality of distracters into account, especially participants’ assessment of the tasks’ difficulty. Listening to portable music is an effective and accessible way to distract subjects without added pressure or too much
cognitive demand. Since it just provides auditory stimulation, it leaves room for
new unconscious manipulations that would need to present visual stimuli. For
example, subjects can listen to music while new applicant information is presented or subliminally primed on the screen. Further studies can also more clearly
determine the mechanism for what makes the more difficult distracters like anagrams impede unconscious decision making. The performance of the hard iPod
participants showed that a more difficult distracter task can reduce unconscious
thought’s efficacy, but perhaps a task that requires a deeper level of processing
(complex memory tasks or other puzzles that require associative thinking) or adds
a higher level of cognitive load would eliminate unconscious thought’s advantages in complex decision making.
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