Sleep Wake Disorders - Sleep - Internet - Personality
INTRODUCTION
Impaired sleep yields a variety of negative consequences, including impaired vigilance,
poor reasoning, and impulse control failures[1]
,
[2]. For these reasons, sleep impairment is detrimental to everyday life, ranging from
performance reductions in academic and work settings to increases in mental illness
and intimate partner violence[3]
-
[5]. Identifying personality vulnerabilities to sleep impairment and the intervening
processes is thus a vital step forward in illuminating ways to lessen the severe burdens
that accompanies sleep loss.
Indeed, personality differences in trait anxiety, depression, and neuroticism more
generally have been extensively linked to poor sleep quality and future insomnia[6]
-
[8]. Building on these findings, we sought to illuminate this link by investigating
which aspect of neuroticism more closely signals poor sleep, namely Withdrawal (anxiety
and depression) or Volatility (anger and defensiveness). Moreover, we examined whether
problematic internet use contributed to this relationship between neuroticism and
sleep problems. Individuals in today’s society use internet more than ever before,
with increased mobile technology use being directly implicated in less sleep and sleep
of poorer quality[9]. To our knowledge this is the first investigation to link distinct aspects of neuroticism
with sleep problems while simultaneously examining the role of internet use.
NEUROTIC VOLATILITY VS. NEUROTIC WITHDRAWAL
NEUROTIC VOLATILITY VS. NEUROTIC WITHDRAWAL
Neuroticism refers to the disposition toward distress and negative emotional states
and is characterized by two aspects reflecting anxiety and dysphoria on one hand,
and anger with irritability on the other[10]
,
[11]. These core personality aspects of neuroticism are labeled Volatility (“Get angry
easily,”) and Withdrawal (“Worry about things”)[10]. These distinct aspects parallel differences between externalizing (e.g., aggressive)
and internalizing (e.g., dysphoric) responses to stressors[12].
Neurotic Volatility reflects behavioral instability and difficulty controlling emotional
impulses. It is linked with tendencies toward irritability and anger, while also showing
association with externalizing problems[12]. An FMRI study indicated that volatility is associated with sensitivity to threatening
stimuli and a general tendency to approach them, even if negative in valence[13].
In contrast, neurotic Withdrawal involves retreat from threatening events while experiencing
negative affect. This negative affect is often evident in self-doubts, a sense of
anxiety, and depressive reactions[10]. This leads individuals to remove themselves from whatever situation aroused those
responses; for example, neurotic withdrawal was linked to a pattern of amygdala activation
indicating a predisposition toward avoidance of threatening stimuli, rather than approach[13]. In this vein, it is thought to be more closely associated with the behavioral inhibition system (as opposed to the behavioral approach system)[10]. In short, neuroticism reflects a general sensitivity to threatening stimuli, although
the expression of that sensitivity is a combination of distinct tendencies toward
volatility and withdrawal.
IS WITHDRAWAL OR VOLATILITY MORE IMPORTANT FOR SLEEP?
IS WITHDRAWAL OR VOLATILITY MORE IMPORTANT FOR SLEEP?
For individuals prone to emotional instability, anxiety, and worry, such tendencies
may be particularly troublesome when distractions aren’t readily available, such as
when trying to sleep. In this vein, neuroticism is predictive of sleep onset problems
both in adolescence (r=.34) and adulthood (r=.25)[14]. A study that used actigraphy to track sleep also confirmed that adolescents who
felt the hallmarks of neuroticism during the day (e.g., anxiety, nervousness, irritability)
slept objectively fewer hours and had longer awakenings that night[15]. Moreover, an analysis of more than 22,000 individuals that neuroticism was both
concurrently and prospectively associated with worsening sleep quality[16]. Although this evidence clearly implicates neuroticism in sleep problems, there
is little data on which aspect of neuroticism (volatility or withdrawal) is more important.
On one hand, Volatility involves externalizing problems (e.g., short-lived angry outbursts)
and should be linked to poorer sleep quality through a connection with chronic anger
and conflict[5]. On the other hand, Withdrawal is associated with loneliness, depression, and anxiety,
all of which have been strongly and consistently tied to sleep problems and development
of insomnia[8]
,
[10]
,
[17]. In the current study we tested the unique and relative importance of these aspects
of neuroticism for sleep disturbances. Moreover, we investigated the intervening role
of an increasingly important factor for sleep, namely internet use.
THE ROLE OF PROBLEMATIC INTERNET USE
THE ROLE OF PROBLEMATIC INTERNET USE
Problematic internet use (uncontrollable use that leads to social-occupational problems)
has been extensively linked to psychiatric and behavioral problems in adolescents
and young adults, with more neurotic individuals being especially prone to compulsive
or extreme internet use[18]
,
[19]. Similarly, problematic internet use may delay sleep onset and it predicts poor
sleep quality[20].
However, it is not clear whether pathological internet use is more relevant to Withdrawal
or Volatility when it comes to individuals’ sleep. On one hand, compulsive and uncontrolled
use of the internet can be driven both by general problems with impulse control and
reward-seeking behavior (implicating volatility), as well as desires to escape personal
distress or loneliness (implicating withdrawal[21]). Given the strong ties between problematic internet use, anxiety, depression, and
sleep disturbance, we anticipated that problematic internet use would mainly contribute
to the link between Withdrawal and sleep problems, contributing less to any link between
Volatility and poor sleep. In line with this premise, one study found that people
high in neuroticism were motivated to pursue online activities in an attempt to escape
loneliness[22]. Importantly, loneliness is also linked to worse sleep quality[23]. Thus, pursuit of online activities can be a manifestation of withdrawal and coping
with negative affect, in that it allows a person to manage their exposure to potentially
threatening stimuli (e.g., avoiding unwanted conversations).
THE CURRENT STUDY
As internet usage becomes ubiquitous, it is necessary to understand its role in tying
personality differences to key aspects of health such as nightly sleep disturbances
and daily fatigue. To this end, the current study examined the links among neuroticism,
problematic internet use, and sleep in a sample of college students. Given the stability
of personality traits and their role in affecting sleep, we hypothesized a model rooted
in neuroticism predicting problematic internet usage and sleep quality. To our knowledge,
this is the first direct examination of the role that problematic internet use plays
in tying different aspects of neuroticism to sleep quality.
First, although we anticipated withdrawal and volatility both to predict sleep quality,
we expected withdrawal to show a stronger unique relation given extensive ties between
anxiety, depression, and sleep problems. Furthermore, we expected that problematic
internet use would predict sleep disturbances and that it would help account for the
link between Withdrawal and worse sleep, but not between Volatility and worse sleep.
While cross-sectional in nature, this study sheds light on important differences in
aspects of neuroticism as they relate to problematic internet use and sleep health.
METHODS
Participants and Procedure
A power analysis using G*Power indicated that 144 observations would be sufficient
to capture a moderate correlation of .27 at .05 level of significance, approximating
correlations between neuroticism and sleep quality reported in prior research[14]. To this end, 143 undergraduate students from a large U.S. university participated
in a large, online study for course credit (age 18-36,M=19.85, SD=2.45; 38.3% female; 76.8% White, 12.7% Asian/Pacific Islander). They completed a
series of surveys relevant to sleep and personality. No other measures of neuroticism,
problematic internet use, or sleep quality were administered except those described
in this report. The study was approved by the local Research Ethics Committee and
all participants provided informed consent.
The measures used in the current study were the Big Five Aspect Scale of Volatility (10 items, α=.859, sample item: “Get easily agitated”) and Withdrawal (10 items, α=.721, “Become overwhelmed by events”[10]
[10]), the Problematic Internet Use Questionnaire (37 items, α=.965; “Have you ever tried to escape your problems by going online?”)[24], and the Pittsburgh
Sleep Quality Index, (PSQI)[25]. Sleep quality on this measure reflects three distinct factors, namely Sleep Efficiency (time asleep relative to time in bed), Perceived Sleep Quality (reported integrity of sleep), and Daily Disturbances (fatigue and sleep interruptions)[26]. No information regarding psychiatric disorders or medication use was collected.
Statistical Analyses
We first examined bivariate correlations between the variables of interest to appraise
the relations between aspects of neuroticism, problematic internet use, and sleep
([Table 1]). We then tested a path model with bootstrapping in Mplus (v.7) with neuroticism
aspects predicted features of sleep quality via problematic indirect use. Besides
total effects linking neuroticism aspects and sleep problems, of key interests were
the indirect effects between distinct aspects of neuroticism and sleep quality through problematic
internet use.
Table 1
Correlations among measures of neuroticism, sleep, and problematic internet use.
|
1
|
2
|
3
|
4
|
5
|
6
|
1. Neuroticism
|
|
|
|
|
|
|
2. Withdrawal
|
.82**
|
|
|
|
|
|
3. Volatility
|
.89**
|
.46**
|
|
|
|
|
4. Problematic Internet Use
|
.34**
|
.36**
|
.22**
|
|
|
|
5. Daily Sleep Disturbance
|
.32**
|
.38**
|
.19*
|
.45**
|
|
|
6. Sleep Efficiency
|
.07
|
.08
|
.05
|
.16*
|
.17*
|
|
7. Perceived Sleep Quality
|
.31**
|
.39**
|
.17*
|
.16
|
.37**
|
.25**
|
Note:
**
p<.01,
*
p<.05.
RESULTS
As anticipated, neuroticism generally predicted worse sleep quality and more problematic
internet use ([Table 1]). Basic correlations also revealed that Withdrawal was more strongly related to
both daily disturbances and sleep quality than was Volatility, in accord with our
first hypothesis (neither aspect of neuroticism was significantly correlated with
self-reported sleep efficiency). In short, these correlations support the hypothesis
Withdrawal is more important for problems with sleep and internet use than is Volatility,
although both matter.
To test our second hypothesis, we further tested the intervening role of problematic
internet use in the relationship between neuroticism and sleep in a model regressing
the three sleep quality factors on problematic internet use and the two aspects of
neuroticism. We focused the analysis on sleep quality and daily disturbances as correlations
indicated that sleep efficiency had little association with neuroticism or problematic
internet use ([Table 1]). This model yielded good fit to the data (χ[2](3)=4.470, p=.215, RMSEA=.059, CFI=.984,
[Figure 1]).
Figure 1 Neuroticism Aspects as Predictors of Sleep Disturbances via Problematic Internet
Use ** p <.01, * p <.05. PIU = Problematic Internet Use. Indirect path from Withdrawal to Daily Disturbance
(b = .11, p = .010). All other indirect paths failed to reach conventional standards for significance.
Enviado por: Zlatan Krizan Krizan.
As expected, the Withdrawal subscale of neuroticism accounted for more variability
in problematic internet use than did volatility (Withdrawal: β=.32, p<.001, 95% CI=.16, .47; Volatility: β=.09, p=.284, CI=-.08, .24). Overall inspection of the links between the aspects of neuroticism
and sleep again reveals that Withdrawal played the stronger role (Daily Disturbance: Withdrawal, β=.25,p=.001, 95% CI=.11, .40; Volatility, β = -.02, p = .84, CI = -.17, .13; Sleep Quality: Withdrawal, β=.38, p=.001, 95% CI=.21, .57; Volatility, β=-.02, p=.881, CI=-.24, .20). Likewise, problematic internet use predicted sleep problems,
specifically daily disturbances (β=.35, p<.001, 95% CI=.16, .52;Sleep Quality, β=-.02, p=.864, 95% CI=-.19, .16). Importantly, such use partially accounted for the relationship
between Withdrawal and Daily Disturbances (β Indirect=.11,p=.010, 95% CI=.04, .22), whereas there was no such indirect link for Volatility (β
Indirect=.03, p=.29, 95% CI=-.02, .09). Taken together, these data support our hypotheses that a)
Withdrawal is more indicative of sleep problems than Volatility and that b) problematic
internet use plays an intervening role in the relationship between neurotic withdrawal
and poor sleep, especially nighttime and daytime disturbances in sleep.
DISCUSSION
The present study investigated a) whether aspects of neuroticism differently related
to sleep quality, b) whether Problematic Internet Use was associated with sleep problems,
and c) whether problematic internet use contributed to the relation between distinct
aspects of neuroticism and sleep. Although the tested model is not causal, our results
suggest that personality tendencies toward withdrawal fuel problematic internet use
that contributes to concomitant sleep problems and their impact on daily functioning.
Although Volatility was correlated with both daytime and nigh-time sleep problems,
these relationships disappeared when Withdrawal and problematic internet use were
taken into account. In contrast, Withdrawal emerged as strongly and uniquely linked
with all of these variables, regardless of Volatility. Also, it appears that problematic
internet use only contributed to Withdrawal’s relationship with reported disturbances,
but not with perceived sleep quality. This indicates that for individuals higher on
Withdrawal, problematic internet use is more indicative of fragmented and dysregulated
sleep, rather than of direct perceptions of poor sleep[26]. Although more compulsive internet use may delay and displace sleep, these results
suggest such use may be especially important for the integrity of sleep and daytime
functioning, and especially among those prone to neurotic withdrawal. Future research
should thus directly focus on identifying aspects of sleep that are most harmed by
problematic use, especially in adolescence that involves frequent use of technology[20].
There are also limitations to this study. The data were cross-sectional in nature
and the analyses are not definitive tests of any causal relations. Although it is
unlikely that current sleep and internet use affected personality traits, this study
cannot definitively determine whether internet use affected individuals’ sleep or
vice versa. Indeed, prospective evidence indicates that developing internet addiction
leads to more hostility and depression over a year, suggesting problematic internet
use can increase neuroticism over the long-term[27]. A longitudinal examination of neuroticism in the context of internet use and sleep
disturbances would allow study of patterns in day-to-day functioning, including reciprocal
relationships. Nevertheless, the current study is novel in its attempt to identify
factors that help explain the role of neuroticism in sleep impairment.
To our knowledge this is the first study to investigate the role of problematic internet
use in that relationship. To people for whom in-person interactions feel threatening,
an online escape may seem preferable-particularly when rumination on daytime interactions
is likely (i.e., while attempting to sleep). Withdrawal appears to prompt people to
seek the comforts they think an online experience can provide, potentially when they
might otherwise be seeking sleep. Furthermore, troubles stemming from withdrawal and
problematic internet use can persist into the day, evident in fatigue and potentially
lower performance in daytime activities. Understanding such vulnerabilities provides
a foundation for developing strategies to ameliorate barriers to quality sleep. For
example, addressing the underlying anxieties experienced by people prone to Withdrawal
could improve their sleepiness, possibly by lowering the amount of online distraction
they seek.