Boredom proneness predicts quality of life in outpatients diagnosed with schizophrenia-spectrum disorders

Abstract

Background:

There is increasing recognition of the clinical significance of boredom associated with functional impairments in schizophrenia. Previous work has highlighted the importance of motivational deficits more broadly, although no study has yet explored the unique effects of boredom on community outcomes.

Aims:

This study aims to measure boredom proneness among outpatients diagnosed with schizophrenia to determine whether it is elevated in this population and to determine its relation to quality-of-life outcomes.

Methods:

A self-report measure of boredom proneness along with standard measures of symptoms and functional status was administered to a community-dwelling sample of schizophrenia outpatients.

Results:

Boredom proneness was found to be elevated in this population and was associated with reduced quality of life, specifically with leisure activity dissatisfaction and reduced sense of financial well-being. Negative symptoms were determined to be associated with reduced work and school functioning.

Conclusion:

This pattern of unique effects on quality of life highlights the clinical relevance of identifying a subjective state of boredom and has theoretical importance in distinguishing boredom proneness specifically from more general avolitional and amotivational conditions that have tended to be the focus of clinical observation and previous research.

Keywords

Boredom quality of life schizophrenia negative symptoms outcomes

Negative symptoms are considered to be a hallmark of schizophrenia, in part because they produce disproportionate functional impairments relative to positive symptoms (Milev, Ho, Arndt, & Andreasen, 2005; Rosenheck, Leslie, & Keefe, 1998). There has been increasing interest in motivational deficits in particular as a central factor in functioning in schizophrenia (Foussias & Remington, 2010). For example, a recent study by Foussias, Mann, Zakzanis, van Reekum and Remington (2009) identified avolition and amotivation as the key negative symptom factors predicting poor quality of life (QOL) in schizophrenia, above and beyond other clinical factors such as anhedonia and depression. The Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) defines avolition as an ‘inability to initiate and persist in goal-directed activities’ (American Psychiatric Association (APA), 2013, p. 818) or alternately as a ‘reduced drive to perform goal-directed behaviour’ (APA, 2013, p. 100).

A distinct and less well-studied subjective state (Goldberg, Eastwood, LaGuardia, & Danckert, 2011), associated with motivational deficits and negative symptoms, is boredom. Boredom is the aversive state of wanting, but being unable, to engage in meaningful activity and arises from an interaction of environmental and psychological variables. Boredom-inducing environments may lack meaningful opportunities for engagement or may offer opportunities that are either overwhelming or underwhelming (Csikszentmihalyi, 2000). A personality trait describing one’s vulnerability to the experience of boredom, known as ‘boredom proneness’, has been identified (Farmer & Sundberg, 1986). The purpose of this study is to establish boredom proneness as a clinically relevant phenomenon related to, yet distinct from, avolition and other negative symptoms in schizophrenia.

Empirical research has demonstrated that boredom is related to a number of clinically relevant problems. Specifically, studies with various populations have found boredom to be associated with aggressiveness (Rupp & Vodanovich, 1997), impaired concentration and cognitive lapses (Carriere, Cheyne, & Smilek, 2008; Todman, 2003), dysphoria and restless, agitated affect (Fahlman, Mercer, Gaskovski, Eastwood, & Eastwood, 2009), somatic complaints (Sommers & Vodanovich, 2000), cannabis use (Schofield et al., 2006), other substance-related problems (Paulson, Coombs, & Richardson, 1990; Pettiford et al., 2007) and impulse control problems such as overeating (Stickney & Miltenberger, 1999; Wilson, 1986), problematic gambling (Blaszczynski, McConaghy, & Frankova, 1990) and self-mutilation (Favazza, 1998).

Clinical observations and preliminary research have suggested that boredom is a clinically significant issue in schizophrenia in particular. For example, Todman (2003) proposed that boredom is a critical factor in outpatient schizophrenia assessment that may contribute to multiple clinical problems, while Todman et al. (2008) found correlations between boredom and hallucination proneness and substance use in a mixed partial hospital program sample including several participants with schizophrenia. Newell, Harries and Ayers (2011) examined boredom in a psychiatric inpatient population, including patients with schizophrenia, and discovered increased boredom among those with schizophrenia as well as associations between boredom, anxiety, depression and decreased self-directed activity – further evidencing the clinical utility of targeting boredom in treatment. Such relationships remain unexamined in an outpatient schizophrenia population, wherein there may be a significantly different impact of boredom proneness on functioning given the much different environment.

Using the experience-sampling method (Csikszentmihalyi & Larson, 1987), Massimini, Csikszentmihalyi, and Carli (1987) empirically established the utility of monitoring ‘optimal experience’ – a balance between environmental offerings for engagement and the skills and desires of the patient – as a way of enhancing outpatient psychiatric rehabilitation. They suggested that suboptimal experience could contribute to an ‘atrophy of behaviour’ (p. 549). However, there have been no studies to date that have attempted to measure boredom as a specific subjective marker of non-optimal experience that results in poor rehabilitation outcome. Despite strong evidence of the potential detrimental effect of boredom in schizophrenia rehabilitation in particular, it is currently unclear whether boredom proneness is elevated among schizophrenia outpatients and what impact it has on functioning. It is also possible that boredom proneness describes a motivational variable not significantly distinct from other negative symptoms in schizophrenia, given the similarities apparent between these constructs.

In summary, no research has yet established the clinical significance, severity and consequences of boredom in schizophrenia outpatients. Indeed, our review suggests that there may be particular utility in assessing boredom from a treatment planning perspective, given the negative behaviors it may trigger, its subjectively distressing nature and the existence of new treatments that focus on boredom and motivational deficits in schizophrenia (e.g. Johns, Sellwood, McGovern & Haddock, 2002). Boredom proneness in this study will therefore be measured in an outpatient chronic schizophrenia sample and assessed for its level relative to controls, its predictive value with regard to functional outcome and its predictive overlap with other negative symptoms that are already routinely assessed.

Methods

Participants

A total of 38 outpatients at a community-based care program for schizophrenia in Hamilton, Ontario, Canada, volunteered for the study (program details were described by Whelton, Pawlick & Cook, 1999). All participants carried diagnoses of a schizophrenia-spectrum disorder according to Diagnostic and Statistical Manual of Mental Disorders, 4th edition, Text revision (DSM-IV-TR) criteria (APA, 2000). Diagnostic types in the sample included paranoid schizophrenia (n = 24), schizoaffective disorder (n = 6), residual schizophrenia (n = 5) and undifferentiated schizophrenia (n = 2). Participants were recruited via flyers distributed by their case workers. One patient was excluded from analyses given a lack of evidence for a schizophrenia-spectrum diagnosis. The recruitment and treatment of participants, consent-obtaining procedures and handling of data were approved by the York University Human Participants Research Ethics Committee. See Table 1 for a summary of participant characteristics.

Table 1.

Participant characteristics.

Variable	Mean	SD	Minimum	Maximum	Maximum possible
Age	44	8.4	21	54	–
Years since diagnosis	24	8.2	5	35	–
Antipsychotic dose^a	585.3	364.8	0	1906	–
PANSS ratings
Positive symptoms	14.5	4.5	7	23	42
Negative symptoms	13.2	4.5	7	24	42
General symptoms	27.2	5.2	16	38	96
Boredom proneness (BPS)	99.1	22.9	45	147	151
QOL^b	5.4	0.8	3.7	7.0	7.0
Weekly structured activity (hours)	9	9.7	0	45	–

SD: standard deviation; BPS: Boredom Proneness Scale; PANSS: Positive and Negative Symptom Scales for Schizophrenia; QOL: quality of life.

Chlorpromazine equivalent (mg).

Mean score on Lehman QOL Interview.

Measures

Positive and Negative Symptom Scales for Schizophrenia

The Positive and Negative Symptom Scales for Schizophrenia (PANSS; Kay, Fiszbein, & Opler, 1987) is a clinician-rated measure of 30 psychiatric symptoms in three domains: positive schizophrenia symptoms, negative schizophrenia symptoms and general psychiatric symptoms. The data for the ratings come from chart review and semi-structured interviews completed by trained clinicians. In this study, the PANSS was administered by trained case workers as part of an annual program evaluation.

Boredom Proneness Scale

The Boredom Proneness Scale (BPS) is a widely used and well-supported measure of the proclivity to experience boredom that has good validity and reliability (Farmer & Sundberg, 1986; Vodanovich, 2003). The temporal stability of boredom proneness is supported by high test–retest reliability, with Pearson’s coefficients ranging from .79 to .91. Its 28 items were presented in a 7-point Likert-style format, alpha coefficients for which have been estimated between .79 and .84 (Vodanovich, 2003).

Lehman’s Quality of Life Interview

The Quality of Life Interview for the Chronically Mentally Ill (Lehman, 1988) provides Likert-style, self-reported ratings of well-being based on a visual analogue scale. Satisfaction is rated by each patient globally as well as in nine life domains, including living situation, family relations, social relations, leisure, work, religious activity (not measured in the current study), finances, safety and health. These ratings are collected by trained clinicians in the context of a semi-structured interview. In this study, interviewers were case workers who conducted the interviews as part of a program evaluation.

Avolition Scale

There is currently no self-report measure that is designed specifically to assess avolition. However, several existing executive and motivational inventories contain items that address those facets of functioning pertinent to motivated, volitional action in clinical and nonclinical samples. These include the ‘Maintain’ subscale of the Brown Attention-Deficit Disorder (ADD) Scales (Brown, 1996), the ‘Behavioral Activation’ subscales of the Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) Scales (Carver & White, 1994), the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 1996) and the Executive Function Index (EFI; Spinella, 2005). In all, 13 items were drawn from these scales to reflect the breadth of functions defined as ‘volitional’ and the various ways in which clinical samples subjectively experience diminished volitional functioning. The items were chosen for content validity and simplicity of language. The content of the 13 items included statements about ability to perform self-initiated action, vigor and enthusiasm in goal pursuit, idleness, procrastination and desire to plan and initiate tasks; specifically, the scale included items 14, 17 and 40 from the Brown ADD Scales; items 3, 4 and 9 from the BIS/BAS Scales; items 6, 14, 20, 49 and 62 from the BRIEF; and items 1 and 4 from the EFI.

In an unpublished study, the Avolition Scale (AS) was administered to 71 undergraduate students at York University who participated voluntarily for course credit (female = 41, mean age = 22.1 years). This study yielded an alpha coefficient for the AS at α = .80 and significant positive correlations with existing measures of related constructs, such as Marin’s Apathy Evaluation Scale (AES; Marin, 1990: r = .66) and Kuhl’s Action Control Scale (Kuhl, 1994: r = .58). In the sample for this study, the alpha coefficient was measured at α = .76.

Procedure

Each participant was visited one-on-one by the researcher and provided written informed consent. They were told that they were being asked to take part in a study examining the relationships between personality variables and symptoms of mental illness and that the study would involve a researcher-conducted chart review and a brief series of questionnaires. They were then administered the series of self-report measures of boredom and avolition described above and given CAD$10 for their participation.

After participation, each patient’s medical chart was accessed and data were extracted concerning participant demographics, diagnosis, and illness onset and duration. Each participant’s scores from their most recent assessment interview for the PANSS as well as their most recent Quality of Life Interview were also obtained. PANSS data from those participants who had not completed a PANSS interview within 3 months of participating (n = 4) were excluded from analyses in a pairwise manner.

Results

Level of boredom proneness

An estimate of the population mean level of boredom for the age cohort represented in the clinical sample (mean age = 44 years) was ascertained from a database of findings from studies conducted by our lab (n = 2592, female = 1858, mean age = 20.8 years, age range 16–56 years) using linear regression. The regression yielded a negative slope, Ŷ = 115.91 + (−.66)X, indicating decreases in boredom proneness with age, replicating previous findings (Essed et al., 2006; Hill, 1975; Vodanovich & Kass, 1990). The regression yielded an expected mean BPS level of Ŷ = 86.9 for the sample. A single-sample t test was then performed to determine whether the measured mean BPS level in the clinical sample (X = 99.1) deviated significantly from this expectancy. This test indicated that boredom proneness in the clinical sample was significantly elevated, mean difference = 13.2, t(36) = 3.24, p = .003.

Boredom and community functioning outcomes

See Table 2 for a summary of correlations between boredom proneness, avolition and clinical variables. The correlations revealed that boredom proneness predicted reduced mean QOL, leisure activity and financial well-being. Partial correlations revealed that these relationships were not determined by the variance shared between boredom and avolition, as measured by either the AS or the Volitional Disturbance subscale of the PANSS. PANSS negative symptom ratings were predictive of work- and school-related QOL.

Table 2.

Pearson’s correlations among study variables (n in parentheses, unless otherwise noted).

	AS	BPS	BPS, AS covaried^a	BPS, VD covaried^b	PANSS
			BPS, AS covaried^a	BPS, VD covaried^b	Positive	Negative	General
PANSS
Positive	−.03 (33)	−.07 (33)	−.08 (30)	−.10 (30)	1.00
Negative	−.02 (33)	.23 (33)	.35 (30)*	.20 (30)	.01 (33)	1.00
General	.27 (33)	.36 (33)*	.24 (30)	.34 (30)	.53 (33)**	.29 (33)	1.00
QOL
Global	−.08 (37)	−.27 (37)	−.31 (34)	−.26 (30)	−.04 (33)	−.22 (33)	−.26 (33)
Living	.00 (37)	−.18 (37)	−.27 (34)	−.20 (30)	−.16 (33)	.05 (33)	−.17 (33)
Leisure	−.20 (37)	−.39 (37)*	−.38 (34)*	−.38 (30)*	.02 (33)	−.26 (33)	−.12 (33)
Family	−.04 (37)	−.12 (37)	−.14 (34)	−.15 (30)	.05 (33)	.10 (33)	−.04 (33)
Social	−.14 (37)	−.32 (37)	−.33 (34)	−.34 (30)	−.10 (33)	.01 (33)	−.03 (33)
Financial	−.27 (37)	−.45 (37)**	−.40 (34)*	−.46 (30)**	−.16 (33)	−.19 (33)	−.30 (33)
Work/School^c	.25 (19)	.16 (19)	−.05 (16)	.16 (14)	.11 (17)	−.62 (17)**	−.01 (17)
Legal/Safety	.00 (37)	−.18 (37)	−.27 (34)	−.19 (30)	.04 (33)	.11 (33)	−.14 (33)
Health	−.05 (37)	−.12 (37)	−.12 (34)	−.13 (30)	.07 (33)	.15 (33)	−.03 (33)
Mean^d	−.13 (37)	−.35 (37)*	−.40 (34)*	−.37 (30)*	−.04 (33)	−.10 (33)	−.18 (33)

AS: Avolition Scale; BPS: Boredom Proneness Scale; PANSS: Positive and Negative Symptom Scales for Schizophrenia; QOL: quality of life; VD: Volitional Disturbance.

Partial correlation between BPS score and other study variables with AS as covariate. df in parentheses.

Partial correlation between BPS score and other study variables with PANSS VD as covariate. df in parentheses.

Participants who were, at the time of their assessment, not employed or enrolled in school were exempt from this analysis.

Mean of all the above QOL subscales.

p < .05.

p < .01.

Correlates of boredom proneness

Boredom proneness was correlated with avolition, r(37) = .76, p < .001, and with PANSS general psychiatric symptoms (see Table 2). The relationship between boredom proneness and negative symptoms was complex. Those with above-median negative symptom levels (median = 13) tended to score above-median in boredom proneness, while the same was not true of those with below-median negative symptom levels. The significance of this trend was tested with a t test, mean difference = 13, t(31) = 1.74, p < .05. However, the Pearson correlation between the two variables was non-significant until avolition was covaried out (see Table 2). Thus, only the unique variance in boredom proneness that was not shared with avolition was predictive of negative symptomatology.

Discussion

This study provided evidence for a specific link between boredom proneness and reduced QOL outcomes in a community-dwelling population with schizophrenia-spectrum diagnoses. The value of assessing boredom proneness in this population was supported via several findings: Boredom proneness was elevated in this sample relative to controls, it predicted outcomes independently of, and beyond, measures of related symptoms and it was measurable as a construct distinct from negative symptoms.

Boredom proneness in this sample was furthermore found to be significantly elevated relative to that of similarly aged controls, supporting the hypothesis of Todman (2003) that boredom may be especially problematic in this population. Boredom may therefore be considered worthy of heightened empirical and clinical attention in schizophrenia, especially given the potential adverse consequences of boredom proneness, reviewed above. Superficially, this result conflicts with that of Todman et al. (2008), who failed to find significantly greater boredom in a partial hospital patient sample with severe, persistent mental illness. However, these authors measured state boredom as opposed to boredom proneness and did not account for age differences between their control (college students) and clinical samples.

This study revealed that boredom proneness predicts mean reductions in QOL ratings provided by clients, highlighting its impact on community-adaptive functioning. There were specific effects of boredom that were most evident: its effects in reducing a sense of financial well-being and in producing lowered satisfaction with leisure activities. In contrast, the QOL domains of reduced work and school adaptive functioning were most clearly associated with other negative symptoms as assessed by the PANSS and were, in fact, not predicted by boredom proneness. These non-overlapping patterns of correlation suggest that distinct phenomena are being assessed by boredom and negative symptom measures and support the clinical utility of assessing boredom proneness in addition to negative symptoms.

Boredom proneness was demonstrated to be distinct, more specifically, from avolition as assessed by both the AS and the PANSS Volitional Disturbance Scale in that it predicted mean QOL, leisure and financial satisfaction outcomes even after shared variance with these volitional measures were covaried out of the correlation, suggesting that the predictive power of boredom is unique and not owing to its relationship with avolition. In fact, it was only after shared variance with the AS was eliminated that the BPS correlated significantly with negative symptoms, suggesting a relationship between boredom proneness and specific negative symptoms apart from avolition.

As a final consideration in support of the distinctiveness of boredom, the correlation between the AS and BPS in this study was significant, but did not approach identity, with each variable only accounting for 58% of the variability in the other. These findings support the hypotheses of previous researchers who have proposed that boredom and motivational and volitional decrements are connected (Blunt & Pychyl, 1998; Farmer & Sundberg, 1986) but measurably distinct (Goldberg et al., 2011).

These findings taken together suggest the distinct predictive power of boredom in particular functional outcome domains and make a strong argument in favor of its incorporation into clinical practice. Functional outcomes form part of the core of the concept of treatment efficacy (Chambless & Hollon, 1998) and improvements in QOL are often a key goal of rehabilitation (Whelton et al., 1999), making the role of boredom proneness in these processes especially relevant to treatment providers and researchers.

One further, practical consideration supporting the utility of assessing boredom is the fact that the experience of boredom is subjectively unpleasant and sometimes intolerably so. Thus, unlike objective signs of the disorder such as clinician-rated volitional decrements, boredom is by definition subjectively aversive and individuals are therefore motivated to resolve it. In a counseling context or case management session, the issue of boredom may provide a topic that patient and provider can agree upon as an impetus to discover those activities that are available to the patient that would provide meaningful opportunities for engagement. This in turn would aid the patient and clinician in tackling inactivity – a severely impairing and prominent feature of many cases of schizophrenia.

There is an apparent discord between these findings and those of Foussias et al. (2009), in which avolition was determined to predict the majority of variability in QOL. This may be attributable to differences in the measures used in the two studies – whereas Foussias et al. used the AES, we employed the PANSS volitional disturbance scale and the AS. As an objectively rated measure of volitional decrement, the PANSS Volitional Disturbance scale may capture phenomena that are distinct from those captured by subjectively rated measures like the AES. Furthermore, the AS, which predominantly includes items related to task initiation and perseverance, may measure phenomena that are subjectively distinct from those captured by the AES, which additionally includes items related to attitudes toward volitional functioning. There may also be critical differences between the QOL measure used in this study, which assesses global QOL concerns, and that used in Foussias et al. (the Heinrichs Quality of Life Scale; Heinrichs, Hanlon, & Carpenter, 1984), which was developed as an assessment of the schizophrenic deficit syndrome and contains items more focally related to avolition and its outcomes, unlike the Lehman (1988) scale used currently.

Several shortcomings are present in this study. The validity of the new AS is still being explored. Although it is a collection of items from established indices that validly measure volitional disturbance, the AS has yet to be fully refined psychometrically. It may be that the AS predominantly taps into only one element of avolition, as there is little current consensus on the definition and etiology of this construct. The Volitional Disturbance subscale of the PANSS, on the other hand, is a well-established measure of avolition and, in the current analyses, performed similarly to the AS in that it did not account for a significant portion of the correlation between boredom proneness and QOL, further bolstering the primary conclusion drawn from the AS and ensuring that the current analysis does not rely on a less well-established scale. However, a further limitation relates to the level of avolition observed in the current sample as assessed by the PANSS: the maximum score on the PANSS Volitional Disturbance scale was 2 (on a scale of 0–6), reflecting mild symptomatology (the AS demonstrated greater variability). It may be that, in a more symptomatic sample, the contribution of volitional disturbance to QOL would be greater and eclipse the contribution of boredom proneness to QOL currently observed. Thus, the current findings should be generalized to more severe or acute populations with caution.

The conclusions that can be generated from the present research are also constrained due to the study’s correlational design. For example, while boredom proneness has been established as a predictor of QOL outcomes, it cannot be determined whether boredom proneness is a cause of poor QOL, an outcome of it or whether their relationship is owing to common contextual or psychological factors. It is possible, for example, that a lack of financial resources creates boredom in that it limits the activities one is able to engage in. This hypothesis does not counter the utility of assessing boredom proneness, however, given that it may still provide patient and clinician with an easily assessed and mutually agreed-upon impetus for change. In addition, as a well-established personality variable with high temporal stability, boredom proneness is considered less likely to change given environmental factors, unlike state boredom, which is highly responsive to immediate environmental constraints.

Conclusion

Boredom proneness has been shown to be elevated among those with schizophrenia and is worthy of clinical and empirical consideration. It can be easily measured via self-report and generates information that has predictive value over and above that obtainable through symptom measures. Its connections with QOL outcomes have been specified and demonstrated to be distinct from predictive value accrued from overlap with the construct of avolition. Boredom furthermore represents an experience that is subjectively aversive and thus potentially amenable to change efforts, providing clinicians and patients with an opportunity for engagement in specific counseling, particularly around dissatisfaction with leisure activities and sense of financial well-being. Given the negative psychological outcomes that have been connected with boredom and its interesting but oblique relationship with motivational deficits more broadly, boredom represents a potentially fruitful avenue of future research for those attempting to understand schizophrenia and the subjective lives of their patients.

Footnotes

Acknowledgements

Logistical support for this study was provided by Susan Genesee and the staff of the Hamilton Program for Schizophrenia (HPS).

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

References

American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (4th ed., text rev.). Washington, DC: Author.

American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing.

Blaszczynski

McConaghy

Frankova

(1990). Boredom proneness in pathological gambling. Psychological Reports, 67, 35–42.

Blunt

Pychyl

(1998). Volitional action and inaction in the lives of undergraduate students: State orientation, procrastination and proneness to boredom. Personality and Individual Differences, 24, 837–846.

Brown

(1996). Brown ADD Scales. San Antonio, TX: Psychological Corporation.

Carriere

Cheyne

Smilek

(2008). Everyday attention lapses and memory failures: The affective consequences of mindlessness. Consciousness and Cognition, 17, 835–847.

Carver

White

(1994). Behavioral inhibition, behavioral activation, and affective responses to impending reward and punishment: The BIS/BAS Scales. Journal of Personality and Social Psychology, 67, 319–333.

Chambless

Hollon

(1998). Defining empirically supported therapies. Journal of Consulting and Clinical Psychology, 66, 7–18.

Csikszentmihalyi

(2000). Boredom. In Kazdin

(Ed.), Encyclopedia of psychology (Vol. 1, pp. 442–444). New York, NY: Oxford University Press.

10.

Csikszentmihalyi

Larson

(1987). Validity and reliability of the experience-sampling method. Journal of Nervous and Mental Disease, 175, 526–536.

11.

Essed

van Staveren

Kok

Ormel

Zeinstra

de Graaf

(2006). The effect of repeated exposure to fruit drinks on intake, pleasantness and boredom in young and elderly adults. Physiology & Behavior, 89, 335–341.

12.

Fahlman

Mercer

Gaskovski

Eastwood

(2009). Does a lack of life meaning cause boredom? Results from psychometric, longitudinal, and experimental analyses. Journal of Social and Clinical Psychology, 28, 307–340.

13.

Farmer

Sundberg

(1986). Boredom proneness: The development and correlates of a new scale. Journal of Personality Assessment, 50, 4–17.

14.

Favazza

(1998). The coming of age of self-mutilation. Journal of Nervous and Mental Disease, 186, 259–268.

15.

Foussias

Mann

Zakzanis

van Reekum

Remington

(2009). Motivational deficits as the central link to functioning in schizophrenia: A pilot study. Schizophrenia Research, 115, 333–337.

16.

Foussias

Remington

(2010). Negative symptoms in schizophrenia: Avolition and Occam’s razor. Schizophrenia Bulletin, 36, 359–369.

17.

Gioia

Isquith

Guy

Kenworthy

(1996). Behavior Rating Inventory of Executive Function. Lutz, FL: Psychological Assessment Resources.

18.

Goldberg

Eastwood

LaGuardia

Danckert

(2011). Boredom: An emotional experience distinct from apathy, anhedonia, or depression. Journal of Social and Clinical Psychology, 30, 647–666.

19.

Heinrichs

Hanlon

Carpenter

(1984). The Quality of Life Scale: An instrument for rating the schizophrenia deficit syndrome. Schizophrenia Bulletin, 10, 388–398.

20.

Hill

(1975). Work variety and individual differences in occupational boredom. Journal of Applied Psychology, 60, 128–131.

21.

Johns

Sellwood

McGovern

Haddock

(2002). Battling boredom: Group cognitive behaviour therapy for negative symptoms of schizophrenia. Behaviour and Cognitive Psychotherapy, 30, 341–346.

22.

Kay

Fiszbein

Opler

(1987). Positive and negative syndrome scale (PANSS) for schizophrenia. Schizophrenia Bulletin, 13, 261–276.

23.

Kuhl

(1994). Action versus state orientation: Psychometric properties of the action control scale (ACS-90). In Kuhl

Beckman

(Eds.), Volition and personality: Action versus state orientation (pp. 47–59). Toronto, ON, Canada: Hogrefe and Huber.

24.

Lehman

(1988). A quality of life interview for the chronically mentally ill. Evaluation and Program Planning, 11, 51–62.

25.

Marin

(1990). Differential diagnosis and classification of apathy. American Journal of Psychiatry, 147, 22–30.

26.

Massimini

Csikszentmihalyi

Carli

(1987). The monitoring of optimal experience: A tool for psychiatric rehabilitation. Journal of Nervous and Mental Disease, 175, 545–549.

27.

Milev

Arndt

Andreasen

(2005). Predictive values of neurocognition and negative symptoms on functional outcome in schizophrenia: A longitudinal first-episode study with 7-year follow-up. American Journal of Psychiatry, 162, 495–506.

28.

Newell

Harries

Ayers

(2011). Boredom proneness in a psychiatric inpatient population. International Journal of Social Psychiatry, 58, 488–495.

29.

Paulson

Coombs

Richardson

(1990). School performance, academic aspirations, and drug use among children and adolescents. Journal of Drug Education, 20, 289–303.

30.

Pettiford

Kozink

Lutz

Kollins

Rose

McClernon

(2007). Increases in impulsivity following smoking abstinence are related to baseline nicotine intake and boredom susceptibility. Addictive Behavior, 32, 2351–2357.

31.

Rosenheck

Leslie

Keefe

(1998). Barriers to employment for people with schizophrenia. Schizophrenia Bulletin, 24, 413–424.

32.

Rupp

Vodanovich

(1997). The role of boredom proneness in self-reported anger and aggression. Journal of Social Behavior and Personality, 12, 925–936.

33.

Schofield

Tennant

Nash

Degenhardt

Cornish

Hobbs

Brennan

(2006). Reasons for cannabis use in psychosis. Australian and New Zealand Journal of Psychiatry, 40, 570–574.

34.

Sommers

Vodanovich

(2000). Boredom proneness: Its relationship to psychological- and physical-health symptoms. Journal of Clinical Psychology, 56, 149–155.

35.

Spinella

(2005). Self-rated executive function: Development of the Executive Function Index. International Journal of Neuroscience, 115, 649–667.

36.

Stickney

Miltenberger

(1999). Evaluating direct and indirect measures for the functional assessment of binge eating. International Journal of Eating Disorders, 26, 195–204.

37.

Todman

(2003). Boredom and psychotic disorders: Cognitive and motivational issues. Psychiatry: Interpersonal and Biological Processes, 66, 146–167.

38.

Todman

Sheypuk

Nelson

Evans

Goldberg

Lehr

(2008). Boredom, hallucination-proneness and hypohedonia in schizophrenia and schizoaffective disorder. In Yip

(Ed.), Schizoaffective disorder: International perspectives on understanding, intervention and rehabilitation (pp. 153–178). New York, NY: Nova Science Publications.

39.

Vodanovich

(2003). Psychometric measures of boredom: A review of the literature. Journal of Psychology: Interdisciplinary and Applied, 137, 569–595.

40.

Vodanovich

Kass

(1990). Age and gender differences in boredom proneness. Journal of Social Behavior and Personality, 5, 297–307.

41.

Whelton

Pawlick

Cook

(1999). Growing with people with a psychiatric disability in a psychosocial rehabilitation program. Psychiatric Rehabilitation, 22, 290–293.

42.

Wilson

(1986). Eating style, obesity and health. Personality and Individual Differences, 7, 215–224.