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Personality and Social Psychology Bulletin
DOI: 10.1177/0146167207310454
2008; 34; 248 Pers Soc Psychol Bull
Oscar Ybarra, Eugene Burnstein, Piotr Winkielman, Matthew C. Keller, Melvin Manis, Emily Chan and Joel Rodriguez
Functioning
Mental Exercising Through Simple Socializing: Social Interaction Promotes General Cognitive
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248
Mental Exercising Through Simple
Socializing: Social Interaction Promotes
General Cognitive Functioning
Oscar Ybarra
University of Michigan
Eugene Burnstein
University of Michigan, University of Warsaw
Piotr Winkielman
University of California, San Diego
Matthew C. Keller
University of Colorado, Boulder
Melvin Manis
University of Michigan
Emily Chan
Colorado College
Joel Rodriguez
U.S. Federal Bureau of Investigation
D
escartes’ famous philosophical statement, “Cogito
ergo sum” or “I think therefore I am” captures a
core aspect of people’s identity, which also seems to be
reflected in the moniker we have placed on our own
species, Homo sapiens, the wise or knowing man. It
appears that the capacity to cogitate holds a special
place in people’s lives. From the first weeks of human
life parents rush to buy whatever new gadgets will allow
their children to blossom mentally. And at the sunset
stages of life, older adults scramble doing various brain
Authors’ Note: This research was supported in part by a seed grant
from the Center for Aging and Cognition: Health, Education, &
Training (CACHET) at the Institute for Social Research and National
Science Foundation Grant BCS-0217294 to Piotr Winkielman. We
thank Amy Kiefer for her help in conducting literature searches, Lynne
Schaberg for her assistance with some of the analyses, and Hal Pashler
and Tim Rickard for helpful discussions. Correspondence should be
addressed to Oscar Ybarra, University of Michigan, Department of
Psychology and Research Center for Group Dynamics, 530 Church
Street, Ann Arbor, MI 48109-1109; e-mail: oybarra@umich.edu.
PSPB, Vol. 34 No. 2, February 2008 248-259
DOI: 10.1177/0146167207310454
© 2008 by the Society for Personality and Social Psychology, Inc.
Social interaction is a central feature of people’s life and
engages a variety of cognitive resources. Thus, social
interaction should facilitate general cognitive function-
ing. Previous studies suggest such a link, but they used
special populations (e.g., elderly with cognitive impair-
ment), measured social interaction indirectly (e.g., via
marital status), and only assessed effects of extended
interaction in correlational designs. Here the relation
between mental functioning and direct indicators of
social interaction was examined in a younger and
healthier population. Study 1 using survey methodology
found a positive relationship between social interaction,
assessed via amount of actual social contact, and cogni-
tive functioning in people from three age groups includ-
ing younger adults. Study 2 using an experimental
design found that a small amount of social interaction
(10 min) can facilitate cognitive performance. The find-
ings are discussed in the context of the benefits social
relationships have for so many aspects of people’s lives.
Keywords: cognitive performance; socializing; mental exer-
cise; social intelligence; executive function; group
living
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teasers to stave off mental decline. In this research we
propose that more social factors, like simply engaging in
social interaction, can also play a role in helping people
stay mentally sharp.
Up until recent history, people’s lives have been dom-
inated by being socially connected and having relation-
ships with others (Aries, 1962). In their classic book,
Cartwright and Zander (1953) allude to this by refer-
ring to an alien who is visiting earth for the first time.
They note that the alien would be impressed by the
amount of time people spend doing things with others.
For example, people tend to gather and live in the same
dwellings, satisfy various biological needs within the
group, depend on the same economic support, rear
children together, and generally care for one another.
People’s education also tends to occur in groups, and
much of the work that occurs in the world is carried out
by people performing duties and activities interdepen-
dently (Cartwright & Zander, 1953). Human life has
traditionally been a socially connected one, possibly one
with deep phylogenetic roots (cf. Jolly, 1966).
In more recent times, though, social connections
among people seem to be on the decline. As Putnam
(2000) has noted in his book, Bowling Alone, there has
been much loss in social capital in the United States over
the last couple of decades. This is evident, for example,
in the decline of the number of organizations people are
part of and the number of meetings they attend that
involve being around others and having face-to-face
interaction. There has also been a decline in family din-
ners and the occasion with which people have friends
over for a visit. Other research indicates that people
have fewer close others they can talk to about their
innermost thoughts and feelings (McPherson, Smith-
Lovin, & Brashears, 2006). Our society appears to be in
a state of social decline, not one in which the environ-
ment is chaotic and people fear for their lives, but one
in which people have fewer interactions and relations
with others.
Having few social connections has been shown to
have important implications for people’s health. For
example, a preference for being with others is strongly
correlated with well-being (Sinha & Verma, 1990;
Triandis et al., 1986), whereas people with low social
support are more prone to mental illness (McGuire &
Raleigh, 1986), depression (Gladstone, Parker, Malhi,
& Wilhelm, 2007), and lower immunocompetence
(Kiecolt-Glaser, Garner, Speicher, Penn, & Glaser
1984). In addition, socially rejected individuals have
been shown to suffer from self-regulation deficits (e.g.,
Baumeister, DeWall, Ciarocco, & Twenge, 2005).
Studies have also shown that fewer social connections
are related to the risk of death even after controlling for
level of health (House, Landis, & Umberson, 1988).
Social interaction and relationships add to people’s
quality of life in numerous ways.
But social interaction might be good not only for
physical health. In the present research we propose that
social interaction can also facilitate cognitive function-
ing,
1
including long-term and short-term effects on
performance. This prediction is grounded in several
lines of research.
Research in social cognition has long emphasized
that the inferential processes underlying social interac-
tion involve a complex set of computations (Heider,
1958; Mead, 1934). For example, a simple exchange of
views between two people requires that they pay atten-
tion to each other, maintain in memory the topic of the
conversation and respective contributions, adapt to
each other’s perspective, infer each other’s beliefs and
desires, assess the situational constraints acting on them
at the time, and inhibit irrelevant or inappropriate
behavior. Some of these processes are automatic, but
others depend on limited-capacity cognitive resources
often subsumed by the term executive functions, which
include capacities such as attention, working memory,
and cognitive control (Shallice, 1988; E. E. Smith &
Jonides, 1999). For example, a host of social cognition
studies has shown that loading working memory can
influence many strategic aspects of social inference
(Gilbert, Pelham, & Krull, 1988; Trope, 1986).
The involvement of general cognitive capacities in
social inference is also documented by social cognitive
neuroscience (Lieberman, Gaunt, Gilbert, & Trope,
2002). For example, the understanding of others’ beliefs
and desires relies on the prefrontal cortex, especially
medial and orbitofrontal cortex—regions that are tradi-
tionally associated with executive function, especially
working memory and attention (e.g., Baron-Cohen &
Ring, 1994; Brunet, Sarfati, Hardy-Bayle, & Decety,
2000; Fletcher et al., 1995; Frith & Frith, 1999; Royall
et al., 2002; E. E. Smith & Jonides, 1999). Similarly,
control over the expression of beliefs and attitudes is
subserved by prefrontal and parietal regions, the same
regions involved in general cognitive control (Amodio
& Frith, 2006; Nielson, Langenecker, & Garavan,
2002). The critical role of these regions in social inter-
action is illustrated by the profound effects of their dam-
age to social reasoning and behavior (Blumberg
et al., 1999; Damasio, 1994; Kling, 1986; Kling & Steklis,
1976; Moll, de Oliveira-Souza, Bramati, & Grafman,
2002; Myers, Swett, & Miller, 1973; Stone, Baron-
Cohen, & Knight, 1998). Of course, there is some dif-
ferentiation of neural mechanisms supporting social and
nonsocial cognition, but for the purpose of our argu-
ment here, we primarily want to highlight the enormous
importance of executive functions for social cognition
(Adolphs, 2001).
Ybarra et al. / SOCIAL INTERACTION AND COGNITIVE PERFORMANCE 249
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Given the evidence for the functional and neural
overlap between social and general cognitive function-
ing, there is remarkably little research testing whether
social interaction can promote cognitive capacities. One
reason for this could be that until recently general cog-
nitive capacities were seen as relatively fixed and not
subject to change, at least in nonclinical populations.
However, this picture is changing in light of several
pieces of evidence. For one, research in cognitive neuro-
science has shown that the actual capacity of working
memory and attention can increase with training and
facilitate performance in novel, unrelated tasks (Olesen,
Westerberg, & Klingberg, 2004; Posner & Rothbart,
2005). Importantly, these effects can be observed in typ-
ical, as well as clinical, populations and can occur after a
few weeks of training, reflecting more permanent effects.
These findings are especially relevant to the present Study
1, which explores long-term effects. However, beneficial
effects of social interaction on cognitive performance
should also be observed with short training episodes, as
we examine in Study 2. In this case, the underlying
mechanisms are better characterized as “resource prim-
ing” or preactivation of general mental operations
involved in both social interaction and cognitive tasks.
This is analogous to how the activation of more specific
procedures and concepts in memory readies semantically
related knowledge and behavioral patterns (Anderson,
1993; E. R. Smith, 1994). Such a mechanism presum-
ably underlies transfer benefits across tasks that share
little common content but engage the same general cog-
nitive skills, such as working memory and attention
(Baddeley, 2002; Singley & Anderson, 1989). In short,
the emerging evidence makes it plausible that engaging
in social interaction should have beneficial effects on
general cognitive skills, even with nonclinical popula-
tions, and that these effects should be observed in both
the long term and short term.
A Possible Relationship Between Social
Interaction and Cognitive Functioning
Some research has considered the relationship
between social interaction and cognitive functioning.
However, in those studies social interaction is usually
not the main focus of the research. Furthermore, many
times it is assessed with very indirect social indicators
(third-party reports) or it is conflated with a variety of
indicators, some of which are poor proxies of actual
social contact (e.g., marital status). In addition, this
research is restricted to elderly populations and tends to
focus on extreme forms of cognitive impairment or even
disease rather than the typical range of mental func-
tioning. Nevertheless, available studies are at least sug-
gestive of a relationship between social interaction and
cognitive functioning.
For example, investigators found that the risk of
developing Alzheimer’s disease was lower for people
who were described by an informant as socially active
than those described as socially inactive (Kondo &
Yamashita, 1990). A recent study has also shown that
the risk of developing Alzheimer’s disease was higher for
people reporting feeling lonely (Wilson et al., 2007).
These findings are additionally buttressed by lab experi-
ments showing that simply imagining that one has been
socially rejected negatively affects cognitive performance
(Baumeister, Twenge, & Nuss, 2002). Additional studies
have also shown that very general indicators of people’s
social environment, such as recreational activities, were
related to a lower incidence of dementia (Fabrigoule
et al., 1995).
Other research has attempted to study more specifi-
cally the features of people’s social networks in relation
to the development of dementia (Fratiglioni, Wand,
Ericsson, Maytan, & Winblad, 2000). In this research
the measure of people’s social networks included mari-
tal status and whether a person lived with a partner or
other persons, number of close social ties (relatives and
close friends), frequency of contact with these various
parties, and the person’s satisfaction with these con-
tacts. The results indicated that low levels of social
engagement were related to an increased risk of devel-
oping dementia.
Finally, some research suggests that at least among
the elderly, social factors are related to general cognitive
functioning and not just extreme impairments. For
example, in studies of noninstitutionalized elderly per-
sons and a high-functioning group of elderly partici-
pants, researchers found that greater social engagement
(e.g., presence of spouse, contact with friends, group
memberships) was associated with better cognitive func-
tioning (Bassuk, Glass, & Berkman, 1999; Seeman,
Lusignolo, Albert, & Berkman, 2001; see also Arbuckle,
Gold, Andres, Schwartzman, & Chaikelson’s, 1992,
study on elderly men).
The Present Research
The preceding studies are encouraging and point to a
potentially important relationship between social fac-
tors and cognitive functioning. However, these studies
bring up various issues. As noted earlier, in some of
these studies vague activities are taken as indicators of
degree of social interaction. In addition, many times a
person’s marital status was not controlled for but included
as an indicator of degree of social interaction and com-
bined with indicators that varied in specificity (e.g., mari-
tal status vs. frequency of contact). Furthermore, the
samples were limited to older adults. Finally, no study
that we know of has shown that social interaction can
250 PERSONALITY AND SOCIAL PSYCHOLOGY BULLETIN
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Ybarra et al. / SOCIAL INTERACTION AND COGNITIVE PERFORMANCE 251
have a direct, causal influence on cognitive performance
and that such effects can result from even small
amounts of social interaction, a finding with potentially
important implications.
In addition to the preceding points, the available
research also leaves unclear two critical issues. The first
issue is the generality of the social interaction effect.
Does social interaction create cognitive benefits only
after substantial periods of time, say months, years, or
decades, and is this what is being captured with the
study of older adults? Or could the positive effects of
social interaction be apparent even for people who have
undergone little cognitive decline? Furthermore, can
such cognitive benefits be visible only after a short
social interaction episode? The second critical issue is
the causal direction. All the social interaction studies so
far have looked at this via correlational measures. This
obviously raises the issue of whether social interaction
per se promotes cognitive functioning or cognitive func-
tioning promotes interaction.
The present research sought to clarify these issues. As
a first step, Study 1 used a survey methodology to
examine whether there is a relationship between cogni-
tive functioning and specific measures of social interac-
tion, rather than nonspecific indicators. Furthermore,
this study focused on cognitive functioning, not extreme
impairment, and whether it relates to social interaction
across different age groups, not just older adults. If a
relationship exists between social interaction and cogni-
tive functioning across age groups, this would suggest
that anyone can stay sharper mentally by engaging in
more social interaction, assuming the relationship is
causal in nature. Study 2 focused on this latter issue by
examining the cognitive effects of social interaction in a
group of younger adults. If cognitive benefits occur, this
would provide a conservative causal test of the direction
of influence from social interaction to better cognitive
functioning given that on average younger adults have
undergone little cognitive decline (Park, 2000), in addi-
tion to showing that small amounts of interaction can
have cognitive benefits.
STUDY 1
Method
Study population. The data for Study 1 came from
personal interviews from the Survey of Americans’
Changing Lives (House, 1986) and consisted of a
national, stratified area probability sample (3,610 of
3,617 interviews available for analysis because of miss-
ing responses). The age range of the participants was
24–96 years of age. The topics covered in the interviews
included interpersonal relationships, sources of satisfac-
tion, social interactions and leisure activities, illness and
traumatic life events, employment and financial status,
physical and psychological well-being, cognitive function-
ing, and other lifestyle and demographic characteristics.
Dependent variables: Cognitive functioning. As part
of the interview, the interviewers assessed participants’
cognitive functioning using the mini-mental exam
(Folstein, Folstein, & McHugh, 1975). The measure
deals with participants’ knowledge of personal informa-
tion (e.g., mother’s maiden name) and current events
(e.g., “Who is the president of the United States?”; range
of scores = 0–7). The mini-mental exam also includes a
simple test of working memory, in which participants
are given a number (i.e., 20) and asked to subtract 3, and
to keep subtracting 3 from each new number they get.
Performance consists of the number of times participants
are able to count backward by three (range of scores =
0–6). Total cognitive performance was computed by
adding the score on the general knowledge questions to
the score on the memory test, with higher scores indicat-
ing better cognitive performance.
Independent variables: Social interaction. The social
interaction variable was simple and clearly got at the
amount of social interaction in which the participants
engaged. The measure consisted of the mean of standard-
ized responses to two questions (r = .29). These questions
assessed the number of times participants talked on the
phone with friends, neighbors, and relatives and how
often they got together with these same parties. These
questions were answered on 6-point scales (1 = never, 3 =
once a week [month], 6 = more than once a day [week]).
Covariates. We controlled for relevant demographic
variables, including participants’ age (measured in
years), level of education (the higher the number, the
higher the grade completed), race and ethnicity, gender,
household income (coded as a continuous variable), and
whether participants were married or living with a part-
ner (0 = no, 1 = yes).
In the analysis we also controlled for measures of
physical health and daily activity levels. The physical
health measure consisted of the number of chronic
health conditions reported by the participant (e.g., inci-
dence of arthritis or rheumatism, high blood pressure,
diabetes, fractures) (range = 0–7). The measure of phys-
ical health is particularly important as a control variable
because it is a strong candidate for explaining variation
not only in sociability (if you are ill you are unlikely to
be very social) but also cognitive functioning (mental
decline reflects physical decline).
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252 PERSONALITY AND SOCIAL PSYCHOLOGY BULLETIN
Participants’ assessments of their activities of daily
living consisted of their responses to two questions that
were scored on 4-point scales (r = .30). These questions
measured the degree to which participants engaged in
active sports or exercise, and how often they took walks
(1 = often, 4 = never). Higher scores on this index indi-
cate lower levels of daily activity.
The experience of depression has been associated
with impaired cognitive functioning in many studies
(Whalley, 2001). Therefore, we also controlled for par-
ticipants’ depressive symptoms. These consisted of four
items that assessed the degree to which participants
endorsed negative self-views and felt low self-efficacy,
for example, “At times I think I am no good at all” and
“There is really no way I can solve the problems I
have.” These questions were answered on 4-point scales
(1 = strongly agree, 2 = agree somewhat, 3 = disagree
somewhat, 4 = strongly disagree; Cronbach’s alpha =
.68). The items were recoded so that higher scores indi-
cate more depressed tendencies.
Results and Discussion
Table 1 presents the means for the social interaction
and cognitive performance measure as a function of age
group. The regression analyses were conducted as a
two-stage elimination procedure. In the first stage only
the covariates were entered into the model predicting
cognitive performance. Any covariate that failed to
meet the p < .10 criterion was excluded from the subse-
quent regression models. The excluded covariates were
income level, daily activity level, and physical health.
2
The second stage of the analysis involved classifying
participants into one of three groups as a function of
their age, young (24–41), middle age (42–64), and older
age (65–96; see Table 2 for regression model results).
Then we performed separate regression analyses within
each age group that included the covariates that met the
stay criterion described previously and, more impor-
tantly, the social interaction variable. A backward elim-
ination method, with a stay criterion of p < .05, was
used to determine whether social interaction predicted
cognitive functioning at the final stage of the regression
analysis. The results indicated that social interaction was
a reliable predictor of cognitive performance. The more
participants interacted socially by talking to and visiting
friends and relatives, the better their performance on
the measure of cognitive functioning. Importantly, this
predictive relationship was reliable for each of the age
groups, including the youngest.
The findings from Study 1 indicate that the more
socially engaged participants were, the higher their level
of cognitive performance. This goes beyond available
research in several ways. We had a direct measure of the
amount of social interaction, and we studied a typical
range of cognitive performance. More importantly, we
examined people of various ages and found that this
relation holds across the whole age spectrum, in the
elderly, middle-age, and youngest groups.
The finding of a reliable association between specific
measures of social interaction and cognitive performance
among the youngest group is important not only empir-
ically but theoretically as well. Specifically, it suggests
that the effect of social interaction does not require an
expanded time line before the benefits become apparent.
And the implications of this possibility are not trivial, as
even a few social interactions may potentially have rec-
ognizable benefits on cognitive performance.
It is important to note that the evidence for Study 1,
and that of the previously reviewed research showing a
relationship between social factors and cognitive func-
tioning, is correlational in nature. Thus, one goal of
TABLE 1: Means and Standard Deviations for the Measures of
Social Interaction and Cognitive Performance as a
Function of Age Group
Age Group MSD
Age range 24–41 (n = 1,183)
Social interaction 4.54 1.10
Cognitive performance 11.74 1.76
Age range 42–64 (n = 1,220)
Social interaction 4.33 1.19
Cognitive performance 11.28 2.25
Age range 65–96 (n = 1,207)
Social interaction 4.43 1.25
Cognitive performance 10.54 3.02
NOTE: The means for the measure of cognitive performance are
based on 7 extra participants (3 for middle age and 4 for older age)
who had missing social interaction data.
TABLE 2: Regression Models Testing the Relationship Between the
Measure of Social Interaction and the Measure of Cognitive
Performance as a Function of Age Group, Controlling for
Reliable Covariates From Stage 1 of Analysis
Cognitive Performance
Multivariate Model bp
Age range 24–41
Social interaction .08 .007
R
2
.34
Age range 42–64
Social interaction .05 .05
R
2
.49
Age range 65–96
Social interaction .094 .0001
R
2
.55
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Study 2 was to conduct an experiment to determine
whether social interaction in a group of younger adults
can have a causal influence on cognitive performance.
Related to this goal, Study 2 also tested the idea of
whether a small amount of social interaction can have
positive cognitive effects.
STUDY 2
The participants in Study 2 were randomly assigned
to one of three conditions. These included a social
interaction condition, an intellectual activities condi-
tion, and a control condition. The control and intellec-
tual activities conditions were included as comparisons.
Given the proposed, stimulating nature of “intellectual”
and more academic activities (e.g., Schooler, Mulatu, &
Oates, 1999), we hypothesized that participants in the
intellectual activities condition would outperform those
in the control condition. Of greater interest, given our
argument that social interaction also helps exercise
people’s brains and minds, and the correlational findings
from Study 1, we hypothesized that participants in the
social interaction condition would also outperform the
controls. We had no strong theoretical basis for expect-
ing differences in performance between the two experi-
mental conditions, but a lack of a difference between the
two would help support the idea that social interaction
is similarly stimulating as activities traditionally charac-
terized as “intellectual” in nature.
Method
Seventy-six participants (age range 18–21) took part
in the experiment. The participants were randomly
assigned to one of three conditions in which they were
run as dyads by an experimenter blind to the hypotheses.
Participants in the social interaction condition engaged
in a discussion of a social issue for 10 min. The issue,
which was the same for all participants, involved privacy
protection, especially in light of recent technological
advances and political events. Through the toss of a coin
the experimenter assigned participants to either the pro
or con position. Then they were given 4 min to read
through the description of the topic and formulate their
positions. They were then given the remaining 6 min to
carry out their discussion, with the participant assigned
the pro position asked to start the discussion.
Participants in the intellectual activities condition did
not interact with each other. Their activity consisted of
three tasks, a reading comprehension task (3 min), a
crossword puzzle (4 min), and a mental rotation task (3
min; total time for the tasks combined was always 10
min). The participants were told that it was okay if
they did not finish the tasks in the allotted time. Control
participants also did not interact with each other, but
their task, which involved watching a 10-min clip of the
sitcom Seinfeld, did have a social component. This
aspect of the control condition helps to additionally dis-
tinguish the processes operating in the social interaction
condition, as research has shown that watching televi-
sion can help people satisfy social needs for interaction
(Gardner, Pickett, & Knowles, 2005). If the social inter-
action participants cognitively outperform the controls,
such a finding would suggest that face-to-face interac-
tion or interacting with a live person is important in
realizing cognitive benefits.
Immediately following the 10 min, regardless of con-
dition, we asked participants to evaluate the activity
they were asked to perform (i.e., social interaction,
intellectual activities, or film clip), indicating how
engaging, stimulating, and enjoyable they found the
task to be (answers ranged from 1 = not at all to 6 =
very much so; Cronbach’s alpha = .80).
Following the evaluation of the respective activities,
for the next phase of the experimental session we
assessed participants’ cognitive functioning. Although
we could have used the cognitive functioning measure
from Study 1 for ease of administration, in this study we
used two different cognitive performance measures that
were more stringent and intensive. They included a mea-
sure of processing speed and working memory. Both of
these types of measures have been associated with vari-
ous forms of cognitive performance and measures of IQ
(e.g., Schatz, Kramer, Ablin, & Matthay, 2000).
The speed of processing task involved making same/
different judgments as quickly as possible about two
patterns of dots that were presented side by side on a
sheet of paper (Park et al., 1996). On each sheet of
paper there were multiple pairs for the participants to
compare. The participants were timed and given 45 s
per sheet (three sheets total) to do as many pattern com-
parisons as possible. The speed of processing score was
determined by taking the number of comparisons par-
ticipants answered correctly (across the three sheets)
and dividing this number by the number of comparisons
attempted to take accuracy into account.
The working memory task (reading span task)
required participants to answer questions about sen-
tences read aloud to them by the experimenter (process-
ing component) while maintaining an element from each
sentence in memory (storage component; Salthouse &
Babcock, 1991). Initially participants were presented
with three sets of two objects. Then participants imme-
diately had to recall the objects. If they recalled at least
two of the three sets of two objects, they moved to the
next trial. For this next trial participants were presented
with three sets of three objects. If they could recall
two of the three sets (of three objects) correctly they
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254 PERSONALITY AND SOCIAL PSYCHOLOGY BULLETIN
proceeded to the next trial, and this could have continued
until participants were presented with three sets of eight
objects. The total number of correctly recalled sets
(across trials) was taken as the measure of working
memory performance.
Finally, after the working memory task participants
filled out some demographic questions and were then fully
debriefed and given course credit for their participation.
Results and Discussion
Table 3 shows the results of the experiment. For each
dependent measure (speed of processing, working
memory), we had two questions. First, does each of the
two experimental groups (intellectual, social) differ
from the control group? Second, do the two experimen-
tal groups differ from each other? We first conducted
overall ANOVAs on each measure of cognitive perfor-
mance and then followed up with planned contrasts to
answer these questions.
In terms of performance on the speed of processing
task (number correct/number attempted), there was an
overall difference in cognitive performance among the
conditions, F(2, 73) = 3.91, p < .02. Planned contrast
analysis on the means shown in Table 3 revealed that
the participants in the intellectual activities condition
outperformed controls, F(1, 48) = 4.23, p < .04. Of
greater interest, social interaction participants also out-
performed controls, F(1, 49) = 5.72, p < .02. In addi-
tion, the two experimental groups did not differ from
each other, F(1, 49) < 1.00. Importantly, there was no
difference in the number of attempts by participants
across the three conditions (M
Intellectual
= 17.12, M
Social
=
17.77, M
Control
= 18.40), F(2, 73) = 1.17, p < .31. Thus,
all participants were equally engaged with the second
phase of the experimental session.
Working memory performance yielded equivalent
results, with overall performance differences across con-
ditions, F(2, 73) = 3.46, p < .04. Contrasts revealed that
intellectual activities condition participants outper-
formed controls in terms of working memory perfor-
mance, F(1, 48) = 4.49, p < .04. Similarly, social
interaction participants also outperformed controls,
F(1, 49) = 7.23, p < .01. Again, both experimental
groups did not differ from each other, F(1, 49) < 1.00.
Before the assessment of cognitive performance, we
asked participants to evaluate the activities they per-
formed (i.e., how enjoyable, engaging, stimulating they
found the activities to be; 1 = not at all, 6 = very much
so). Responses to these questions are of interest because
it could be argued that mood or related motivational
differences due to the experimental manipulation could
have influenced cognitive performance. For example,
participants in the video clip condition might have
really enjoyed their activity and might have wanted to
prolong it, which could have subsequently lowered their
motivation when they were put through the cognitive
performance measures. Although the lack of a differ-
ence on the number of attempts on the speed of pro-
cessing task helps argue against this possibility, we
wanted to examine the effects, if any, of how the activ-
ities were evaluated. We first analyzed whether there
were any differences in evaluation. A between-subjects
ANOVA across the three conditions showed no reliable
differences, F(2, 73) = 2.74, p < .07. And even though
there was a trend toward an overall difference, both the
control (video) and social interaction conditions were
rated more favorably than the intellectual activities con-
dition and not differently from each other (M
Intellectual
=
3.39, M
Social Interaction
= 4.05, M
Control
= 3.91). This in itself
also argues against such an alternative account.
To further buttress this aspect of the results, we
included the activity evaluation score as a covariate and
repeated the analyses for speed of processing and work-
ing memory. The addition of this covariate did not alter
the results for either measure of cognitive performance:
speed of processing, F(2, 72) = 3.91, p < .02; working
memory, F(2, 72) = 3.38, p < .04.
The results from Study 2 showed that short-term
social interaction lasting 10 min boosted participants’
cognitive performance to a comparable extent as having
participants engage in so-called intellectual activities for
the same amount of time. To our knowledge, this experi-
ment represents the only causal evidence of the facilitative
TABLE 3: Cognitive Performance as a Function of Experimental Condition
Condition
Social Interaction Intellectual Control
(n
=
26) (n
=
25) (n
=
25)
Cognitive Performance
Measure MSDMSDMSD
Speed of processing 0.95 0.042 0.94 0.045 0.91 0.071
Working memory 10.54 1.42 10.52 2.02 9.48 1.39
NOTE: The greater the score, the better the performance.
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effects of direct social interaction on cognitive perfor-
mance (and maybe the only causal test of the influence
of intellectual activities as well).
The focus on cognitively thriving younger adults in
the present study, in addition to extending the purview
of the social interaction–cognition link, served as a con-
servative test of the proposed causal influence of social
interaction on cognitive functioning given that older
adults perform more poorly than younger adults on a
variety of cognitive functioning tasks (refer to Study 1;
see also Craik, & Byrd, 1982; for a review see Park,
2000). Along more theoretical lines, the findings indi-
cate that the effects of social interaction can be rela-
tively immediate and can result from just a small
amount of social interaction.
Experimenter observations of the social interactions
in the present study indicated that participants planned
their positions, took turns sharing them, anticipated the
partner’s points, and readied their counterpoints. Save
for the constraints in which the interaction took place,
the interactions appeared for the most part natural and
coordinated. Although we do not have direct evidence
for this, the interactions likely triggered the use of per-
spective taking, planning, and inference generation,
processes that have been associated with executive func-
tioning (Amodio & Frith, 2006; Baddeley, 2002). We
posit that it is this that allows social interaction,
through the preactivation of cognitive resources, to
boost subsequent mental performance in a similar way
to how the activation of specific concepts in memory
readies semantically related knowledge and processes
(Anderson, 1993; E. R. Smith, 1994). We argue that
this process of resource priming (brief exercises of exec-
utive functions), which helps explain the effects of Study
2, if practiced regularly can create a more chronic ele-
vation of cognitive resources, which may be the process
captured in Study 1 (Olesen et al., 2004; Posner &
Rothbart, 2005).
At this point, our findings and interpretation agree
with cognitive and social neuroscience research, but
only through future research will we be in a position to
accept these interpretations more confidently. Some of
this work might involve, for example, studying different
types of interactions (getting to know someone or chit-
chatting vs. discussion of an issue), manipulating the
issue under discussion, introducing greater structure
into the social interaction to target specific social cogni-
tive processes (e.g., separately manipulating perspective
taking, mentalizing, or inhibition components), and
using neuroscience techniques to understand neural
changes underlying the observed effects. We will con-
tinue our considerations of how social interactions can
differ and their likely effects on cognition in the general
discussion.
GENERAL DISCUSSION
Both studies suggest a facilitative effect of social inter-
action on intellectual performance. Study 1 showed that
specific indicators of social interaction predicted cogni-
tive performance among cognitively healthy participants
and that this effect extends across a wide age spectrum,
including the youngest participants. This study extended
previous research with elderly and cognitively impaired
populations. Study 2 followed up on these results by
focusing on younger adults and the possibility that small
amounts of social interaction can have causal effects on
boosting cognitive performance. Compared to control
participants, participants who interacted socially for 10
min showed better cognitive performance, performance
equivalent to that displayed by participants engaged in
so-called intellectual activities.
The findings showing that younger adults can reap
cognitive benefits from socializing expand our concep-
tions of the social interaction–cognition link. Not only
do the results show that the effect is causal but that the
process is very sensitive to small amounts of social inter-
action. Reliance on the survey results with elderly par-
ticipants, barring any consideration of measurement
issues, provides little clue that such an effect could
occur so immediately.
The process thus seems aligned with the possibility
that social interaction can “exercise” general cognitive
processes (working memory, speed of processing, inhi-
bition) in the service of social cognition (e.g., empathy,
mentalizing, symbolic interaction). It is possible that as
people engage socially and mentally with others, they
receive relatively immediate cognitive boosts, which
then facilitate subsequent social interactions, receiving
additional cognitive boosts, and so forth. This perspec-
tive suggests that anyone, older and younger alike, can
do things that come naturally to most of us to stay cog-
nitively engaged.
More generally, the current findings fit with the
emphasis in the social cognition literature on the role of
general processing resources in person perception and
judgment (Lieberman et al., 2002). They also fit with
recent research showing real practice-related changes in
brain substrates underlying such fundamental functions
as attention, working memory, and processing speed
(Olesen et al., 2004; Posner & Rothbart, 2005).
Importantly, these changes can occur in typical popula-
tions and can have short-term influences, presumably
based on general mechanisms of activation, as well as
long-term influences, presumably based on structural
changes (Draganski et al., 2004). These findings are also
consistent with research on other species showing that
social enrichment improves cognitive performance, neu-
ronal growth, and overall brain mass (Bennet, Rosenzweig,
Ybarra et al. / SOCIAL INTERACTION AND COGNITIVE PERFORMANCE 255
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& Diamond, 1969; Cummins, 1973; Lipkind, Nottebohm,
Rado, & Barnea, 2002; Lomassese et al., 2000; Menzel,
Davenport, & Rogers, 1970; Sandeman & Sandeman,
2000).
The Nature and Tenor of the Social Interaction
One issue that remains unclear from the present
research is whether all types of social interaction can
have a positive effect on cognitive performance. Some
available research, although varying in method from the
present research, suggests that some social interactions
can be cognitively depleting (Finkel et al., 2006;
Richeson & Trawalter, 2005; Richeson, Trawalter, &
Shelton, 2005). For example, using a measure of inhibi-
tion, Richeson et al. (2005) showed that individuals
high in prejudice or who had concerns about being
viewed as prejudiced were worse at inhibiting interfer-
ing responses on a Stroop task. The research by Finkel
et al. (2006) using as outcome measures anagrams and
analytical tests from the Graduate Record Exam found
depletion effects following interactions that were asyn-
chronous or high-maintenance in nature. Both sets of
findings were explained in terms of self-regulation
deficits, although the emphases differed.
At a broader level, though, it may be possible to inte-
grate these findings with the present research. Whether
a social interaction is cognitively draining or cognitively
energizing may depend on several factors. Most gener-
ally, it is worth noting that the emergence of facilitation
or depletion effects with executive function tasks
depends on the extent of resource pre-use. As an anal-
ogy, before a competition, athletes engage in warm-up
exercises, without overdoing them and tiring themselves
out. Similarly, performance on executive function tasks
should benefit from earlier tasks with low and moder-
ate difficulty and self-timing that allows for rest (e.g.,
our Study 2), but performance may be temporarily
impaired by earlier tasks with high levels of difficulty,
as typically used in depletion experiments (Muraven &
Baumeister, 2000).
More specific to the nature of the social interactions,
their effects should generally depend on whether the
context involves approach or avoidance tendencies, two
core aspects of how people tend to relate to each other
(Chance, 1988). Social interactions that trigger avoid-
ance are likely to be surrounded by a lack of structure
or norms or an asynchronous dynamic, or they may
involve people who under normal circumstances might
not interact with each other or do so warily (e.g.,
strangers, outgroup members). Such social interactions
may induce uncertainty and anxiety about what the
other persons are like, how they will react, or what they
are likely to do (cf. Stephan & Stephan, 1985), out-
comes that may be particularly lethal to the ability to
self-regulate and to concomitant cognitive performance.
In the research by Richeson et al. (2005), participants
were made to feel concerned that they might be viewed
as prejudiced, which might have induced anxiety and
uncertainty, especially when they were told they would
be videotaped and asked to disclose their opinions on
racially sensitive topics. It is also possible that the high-
maintenance conditions in the research by Finkel et al.
(2006) might have induced frustration and facilitated
inferences that the partner was not to be trusted, an out-
come with the potential to short-circuit processes such
as perspective taking.
Other interactions, in contrast, are more structured
or allow for coordination, or may involve people who
are more likely to interact with each other (e.g., friends,
ingroup members). Such interactions, instead of elicit-
ing a self-protective, reactive stance, may induce greater
security, less anxiety, and at times greater communality.
This captures to some degree the nature of the social
interaction used in Study 2, in which participants inter-
acted in a structured setting in which they were rela-
tively interdependent and had to try to predict and
understand each other’s position. It may be this aspect
of the social interaction that promotes a cognitive style
that supports consequent cognitive boosts.
Finally, the possibility exists that the outcome mea-
sures used across the different studies may also play a
role in determining whether cognitive depletion or cog-
nitive boosts occur. Richeson et al. (2005) used a test of
cognitive inhibition, whereas Finkel et al. (2006) used
anagram and analytical reasoning tasks, in addition to
tasks that involved handgrip effort and fine motor con-
trol. In the present research we used two general mea-
sures of cognitive resources, working memory and
speed of processing. Further research is thus needed to
more clearly determine what aspects of social interac-
tion lead to cognitive boosts or cognitive depletion and
the possible role of how cognitive performance is mea-
sured. The former emphasis strikes us as a particularly
exciting area of inquiry. It has potential implications for
research dealing with, for example, the effects of inter-
group contact and diversity on cognitive performance,
and how supportive and coordinated relationships,
both romantic and nonromantic, may allow people to
blossom cognitively.
Limitations of the Present Research
In addition to the issues discussed previously, a limi-
tation of the present research concerns the correlational
nature of Study 1. Although the findings from Study 2
provide causal evidence for the effect of social interac-
tion on cognitive functioning, we cannot draw this con-
clusion with the same level of confidence for Study 1.
The findings from Study 1 are equally suggestive of the
256 PERSONALITY AND SOCIAL PSYCHOLOGY BULLETIN
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Ybarra et al. / SOCIAL INTERACTION AND COGNITIVE PERFORMANCE 257
idea that people who are functioning better cognitively
are better able to enter into social interactions with oth-
ers, or there could be a third variable that accounts for
both of these possibilities. At a broader level, though,
the idea that more cognitively able people may enter
into more social interactions is not inconsistent with the
thrust of the present research. Such a relationship sug-
gests that social interaction demands a requisite level of
cognitive functioning, in line with the suggestions put
forth by evolutionary biologists (Dunbar, 1992, 1995;
Humphrey, 1976). It may indeed be this possibility that
allows for social interaction to produce boosts in cogni-
tive functioning, as demonstrated in Study 2.
The Social Is What We Do, and
Thinking Is for Doing
In the Introduction we discussed how an alien visit-
ing from another world would be impressed by the
amount of time people spend doing things with other
people. What is important to note is that such an alien
could pay a visit now, could have visited 50,000 years
ago, or 2 million years ago (in the time of Homo habilis)
and in all cases be impressed by the role of social rela-
tions in people’s lives. Social connections are at the core
of primate life (Jolly, 1966) and are central to the
human survival strategy (Barash, 1986; Baumeister,
2005; Dunbar, 1992, 1998).
Given the continual and tonic role of social interac-
tion in people’s lives, more specifically, the necessity to
navigate a complex web of social relations in a mixed-
motive world (Humphrey, 1976), it makes sense that our
brains and minds would be very sensitive and responsive
to that dimension of experience. Research in evolution-
ary biology has shown, for example, that the size of the
primate neocortex is better predicted by how cognitively
taxing a primate’s species social environment is (as
reflected in group size) rather than the demands of the
physical ecology (Dunbar, 1992, 1995; Humphrey,
1976). In humans, research in social cognition has
shown that compared to information of a nonsocial
nature, people are faster at recognizing information that
has social implications (Ybarra, Chan, & Park, 2001).
Other research has shown that when people are first get-
ting to know someone, they seek more information
about the person’s social rather than non-social-related
tendencies (Wojciszke, Bazinska, & Jaworski, 1998).
People’s conversations with others also tend to revolve
around the social dimensions of life (Dunbar, Marriott,
& Duncan, 1997), and even while sleeping and dream-
ing people’s minds are preoccupied with social relations
(McNamara, McLaren, Smith, Brown, & Stickgold,
2005). Social neuroscience research has also shown that
the default neural activity present in the human brain is
more aligned with the way people process social versus
nonsocial information (Mitchell, Heatherton, &
Macrae, 2002). People’s psychology appears to be con-
sistently attuned to the social world.
The social readiness of people’s minds makes sense
given that people’s cognitive abilities many times oper-
ate in the service of social coordination and staying
socially connected. In turn, social interaction and rela-
tionships not only sharpen our knowledge and social
skills but also strengthen the cognitive processes that
underlie those skills, which may then ready people for
greater connection and effectiveness in dealing with oth-
ers. Thus, an important outcome of social interaction
appears to be mental sharpness, which in itself may play
a central role in helping us enjoy the many other bene-
fits that come from being socially connected. Thinking
many times is for being social, and being social supports
our thinking.
Conclusion
The current analysis complements other recommen-
dations given for maintaining a healthy brain and mind
(e.g., Verghese et al., 2003; Wilson et al., 2002). Usually
it is assumed that activities that work the brain and
mind are of a more “intellectual” and “technical”
nature, such as reading, developing new hobbies, and
learning to appreciate new aspects of one’s culture (e.g.,
art, music). Such activities should undoubtedly play a
role in keeping the brain and mind healthy.
But in light of current research and discussion, it may
not be inappropriate to rephrase Descartes’ philosophi-
cal statement as “I think about and with others, there-
fore I am.” Other needs that are basic to us, such as
being socially connected (Baumeister & Leary, 1995),
by their very nature when fulfilled will engage people
mentally. The mental gymnastics that come with social
interaction need not take the place of other activities
that exercise our minds, but they may produce the
byproduct, whether intentional or not, of making our
social lives more gratifying while providing boosts to
our cognitive functioning.
NOTES
1. Some critics challenge Putnam’s (2000) “Bowling alone” con-
clusion and suggest that people have as many social contacts now as
in the past but that much of this social interaction has shifted to the
Internet. However, what might be critical for proper cognitive and
physical functioning is actual, face-to-face interaction with its
dynamic and fast character. No amount of email, even “instant mes-
saging,” can supplement face-to-face interaction, as it does not have
the same computational demands.
2. The analyses were also performed with all of the covariates
included as part of the regression models (no exclusion). These analy-
ses produced the same results as those reported.
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258 PERSONALITY AND SOCIAL PSYCHOLOGY BULLETIN
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Received March 11, 2007
Revision accepted August 10, 2007
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