Clinical Instructor, Psychiatry and Behavioral Sciences
Honors & Awards
Young Investigator Research Forum Selected Attendee, American Academy of Sleep Medicine (2015)
Sheldon J. Korchin Prize for Excellence in Dissertation Research, University of California, Berkeley (2012)
Trainee Award for Research Excellence, Sleep Research Society (2011)
Student Research Award, Association of Behavioral and Cognitive Therapies (ABCT) (2009)
Graduate Research Fellowship, National Science Foundation (2008-2011)
Regent’s Intern Fellowship for Academic Excellence, University of California, Berkeley (2006-2008)
Graduation with Distinction, Summa Cum Laude, Stanford University (2004)
Psychology Grant for Undergraduate Research, Stanford University (2004)
Undergraduate Research Grant, Stanford University (2004)
Current Research and Scholarly Interests
Dr. Kaplan's research interests span four (often overlapping) domains: (1) pathophysiologic aspects of insomnia and hypersomnia in mood disorders, including mechanisms, correlates, and sequelae of these sleep disturbances; (2) behavioral interventions for sleep disturbances in adults and adolescents; (3) circadian and psychosocial factors impacting sleep in adolescence; and (4) machine learning approaches to big data.
- Hypersomnia: an overlooked, but not overestimated, sleep disturbance in bipolar disorder. Evidence-based mental health 2017
When a gold standard isn't so golden: Lack of prediction of subjective sleep quality from sleep polysomnography.
2017; 123: 37-46
Reports of subjective sleep quality are frequently collected in research and clinical practice. It is unclear, however, how well polysomnographic measures of sleep correlate with subjective reports of prior-night sleep quality in elderly men and women. Furthermore, the relative importance of various polysomnographic, demographic and clinical characteristics in predicting subjective sleep quality is not known. We sought to determine the correlates of subjective sleep quality in older adults using more recently developed machine learning algorithms that are suitable for selecting and ranking important variables.Community-dwelling older men (n=1024) and women (n=459), a subset of those participating in the Osteoporotic Fractures in Men study and the Study of Osteoporotic Fractures study, respectively, completed a single night of at-home polysomnographic recording of sleep followed by a set of morning questions concerning the prior night's sleep quality. Questionnaires concerning demographics and psychological characteristics were also collected prior to the overnight recording and entered into multivariable models. Two machine learning algorithms, lasso penalized regression and random forests, determined variable selection and the ordering of variable importance separately for men and women.Thirty-eight sleep, demographic and clinical correlates of sleep quality were considered. Together, these multivariable models explained only 11-17% of the variance in predicting subjective sleep quality. Objective sleep efficiency emerged as the strongest correlate of subjective sleep quality across all models, and across both sexes. Greater total sleep time and sleep stage transitions were also significant objective correlates of subjective sleep quality. The amount of slow wave sleep obtained was not determined to be important.Overall, the commonly obtained measures of polysomnographically-defined sleep contributed little to subjective ratings of prior-night sleep quality. Though they explained relatively little of the variance, sleep efficiency, total sleep time and sleep stage transitions were among the most important objective correlates.
View details for DOI 10.1016/j.biopsycho.2016.11.010
View details for PubMedID 27889439
View details for PubMedCentralID PMC5292065
Aberrant nocturnal cortisol and disease progression in women with breast cancer
BREAST CANCER RESEARCH AND TREATMENT
2016; 158 (1): 43-50
While a relationship between disruption of circadian rhythms and the progression of cancer has been hypothesized in field and epidemiologic studies, it has never been unequivocally demonstrated. We determined the circadian rhythm of cortisol and sleep in women with advanced breast cancer (ABC) under the conditions necessary to allow for the precise measurement of these variables. Women with ABC (n = 97) and age-matched controls (n = 24) took part in a 24-h intensive physiological monitoring study involving polysomnographic sleep measures and high-density plasma sampling. Sleep was scored using both standard clinical metrics and power spectral analysis. Three-harmonic regression analysis and functional data analysis were used to assess the 24-h and sleep-associated patterns of plasma cortisol, respectively. The circadian pattern of plasma cortisol as described by its timing, timing relative to sleep, or amplitude was indistinguishable between women with ABC and age-matched controls (p's > 0.11, t-tests). There was, however, an aberrant spike of cortisol during the sleep of a subset of women, during which there was an eightfold increase in the amount of objectively measured wake time (p < 0.004, Wilcoxon Signed-Rank). This cortisol aberration was associated with cancer progression such that the larger the aberration, the shorter the disease-free interval (time from initial diagnosis to metastasis; r = -0.30, p = 0.004; linear regression). The same aberrant spike was present in a similar percent of women without ABC and associated with concomitant sleep disruption. A greater understanding of this sleep-related cortisol abnormality, possibly a vulnerability trait, is likely important in our understanding of individual variation in the progression of cancer.
View details for DOI 10.1007/s10549-016-3864-2
View details for Web of Science ID 000379494200005
View details for PubMedID 27314577
Treating Insomnia Improves Mood State, Sleep, and Functioning in Bipolar Disorder: A Pilot Randomized Controlled Trial
JOURNAL OF CONSULTING AND CLINICAL PSYCHOLOGY
2015; 83 (3): 564-577
To determine if a treatment for interepisode bipolar disorder I patients with insomnia improves mood state, sleep, and functioning.Alongside psychiatric care, interepisode bipolar disorder I participants with insomnia were randomly allocated to a bipolar disorder-specific modification of cognitive behavior therapy for insomnia (CBTI-BP; n = 30) or psychoeducation (PE; n = 28) as a comparison condition. Outcomes were assessed at baseline, the end of 8 sessions of treatment, and 6 months later. This pilot was conducted to determine initial feasibility and generate effect size estimates.During the 6-month follow-up, the CBTI-BP group had fewer days in a bipolar episode relative to the PE group (3.3 days vs. 25.5 days). The CBTI-BP group also experienced a significantly lower hypomania/mania relapse rate (4.6% vs. 31.6%) and a marginally lower overall mood episode relapse rate (13.6% vs. 42.1%) compared with the PE group. Relative to PE, CBTI-BP reduced insomnia severity and led to higher rates of insomnia remission at posttreatment and marginally higher rates at 6 months. Both CBTI-BP and PE showed statistically significant improvement on selected sleep and functional impairment measures. The effects of treatment were well sustained through follow-up for most outcomes, although some decline on secondary sleep benefits was observed.CBTI-BP was associated with reduced risk of mood episode relapse and improved sleep and functioning on certain outcomes in bipolar disorder. Hence, sleep disturbance appears to be an important pathway contributing to bipolar disorder. The need to develop bipolar disorder-specific sleep diary scoring standards is highlighted.
View details for DOI 10.1037/a0038655
View details for Web of Science ID 000355167300013
View details for PubMedID 25622197
Interventions for Sleep Disturbance in Bipolar Disorder.
Sleep medicine clinics
2015; 10 (1): 101-105
Bipolar disorder is a severe and chronic disorder, ranked in the top 10 leading causes of disability worldwide. Sleep disturbances are strongly coupled with interepisode dysfunction and symptom worsening in bipolar disorder. Experimental studies suggest that sleep deprivation can trigger manic relapse. There is evidence that sleep deprivation can have an adverse impact on emotion regulation the following day. The clinical management of the sleep disturbances experienced by bipolar patients, including insomnia, hypersomnia delayed sleep phase, and irregular sleep-wake schedule, may include medication approaches, psychological interventions, light therapies and sleep deprivation.
View details for PubMedID 25750600
- Hypersomnia Subtypes, Sleep and Relapse in Bipolar Disorder Psychological Medicine 2015
- Behavioral Treatment of Insomnia in Early Recovery JOURNAL OF ADDICTION MEDICINE 2014; 8 (6): 395-398
An Evidence-Based Review of Insomnia Treatment in Early Recovery
JOURNAL OF ADDICTION MEDICINE
2014; 8 (6): 389-394
Accruing evidence indicates that insomnia is prevalent and persistent in early recovery from substance use disorders and may predict relapse. As such, insomnia treatment after abstinence represents an important area for intervention. This article reviews the literature on insomnia predicting new-onset alcohol and substance use disorders, along with evidence for insomnia predicting relapse in recovering populations. Pharmacological and psychological treatment options are presented, and cognitive-behavioral therapy for insomnia applied to recovering populations is described in detail.
View details for DOI 10.1097/ADM.0000000000000052
View details for Web of Science ID 000345117200001
View details for PubMedID 25369938
Physical activity and sleep: Day-to-day associations among individuals with and without bipolar disorder
MENTAL HEALTH AND PHYSICAL ACTIVITY
2014; 7 (3): 183-190
To evaluate the relative role of psychopathology in the relationship between physical activity and sleep, the present study investigated the day-to-day relationship between physical activity and sleep in individuals without a psychiatric disorder and individuals with bipolar disorder using a longitudinal, naturalistic design.Participants in two groups-a healthy group with no psychiatric illness (N=36) and an inter-episode bipolar disorder group (N=32)- were studied over a two-month period. Physical health was assessed by the SF-36. Daily subjective and objective measures of physical activity and sleep were collected. A total of 6,670 physical activity measurements and 6,548 sleep measurements were logged.The bipolar disorder group exhibited poorer physical health on the SF-36 and more sleep disturbance relative to the healthy group. No group differences were found in physical activity, nor in models examining the relationship between physical activity and sleep. Hierarchical linear models indicated that for every standard deviation increase in sleep disturbance (i.e., increased total wake time), there was a three percent decrease in subsequent day physical activity, in both the healthy and bipolar groups. Increased physical activity was associated with improved sleep for participants who reported greater average sleep disturbance.The results for all participants in the study suggest that reduced physical activity and sleep difficulties may be mutually maintaining processes, particularly for individuals who suffer from poor sleep. Findings also raise the potential importance of targeting physical activity and sleep concurrently in interventions aimed at improving physical and mental health.
View details for DOI 10.1016/j.mhpa.2014.05.003
View details for Web of Science ID 000348615000010
- Prevalence and clinical correlates of co-occurring insomnia and hypersomnia symptoms in depression. Journal of Affective Disorders 2014
Insomnia comorbid to severe psychiatric illness.
Sleep medicine clinics
2013; 8 (3): 361-371
In psychiatric illness, there is a growing body of evidence indicating that sleep disturbances exert a detrimental influence on the course of these disorders and contribute to impaired function. Even when psychiatric disorders are successfully treated or stabilized, insomnia and other sleep disturbances often fail to remit. The present review focuses on sleep in two severe mental illnesses, namely bipolar disorder and schizophrenia. This article discusses the role of sleep disturbances and altered sleep architecture in relation to symptom status, functional impairment, quality of life, and the course of these disorders. Current evidence regarding pharmacological and psychological treatment approaches for insomnia in these populations is presented. This review also notes considerations for adapting Cognitive Behavioral Therapy for insomnia (CBT-I) procedures for severe mental illness and proposes directions for future research.
View details for PubMedID 25302060
- Treatment of sleep disturbance Clinical handbook of psychological disorders Guilford Press. 2013; 5
- Cognitive therapy for insomnia Encyclopedia of Sleep Academic Press. 2013: 290–295
- Behavioral treatment of insomnia in bipolar disorder. American Journal of Psychiatry 2013; 7 (170): 716-720
Restless Pillow, Ruffled Mind: Sleep and Affect Coupling in Interepisode Bipolar Disorder
JOURNAL OF ABNORMAL PSYCHOLOGY
2012; 121 (4): 863-873
Disturbances in sleep and affect are prominent features of bipolar disorder, even during interepisode periods. Few longitudinal studies have prospectively examined the relationship between naturally occurring sleep and affect, and no studies to date have done so during interepisode periods of bipolar disorder and using the entire set of "gold standard" sleep parameters. Participants diagnosed with bipolar I disorder who were interepisode (n = 32) and healthy controls (n = 36) completed diagnostic and symptom severity interviews, and a daily sleep and affect diary, as well as an actigraphy sleep assessment, for eight weeks (M = 54 days, ± 8 days). Mutual information analysis was used to assess the degree of statistical dependence, or coupling, between time series data of sleep and affect. As measured by actigraphy, longer sleep onset latency was coupled with higher negative affect more strongly in the bipolar group than in the control group. As measured by sleep diary, longer wakefulness after sleep onset and lower sleep efficiency were coupled with higher negative affect significantly more strongly in the bipolar group than in the control group. By contrast, there were no significant differences between groups in the degree of coupling between any measures of sleep and positive affect. Findings support the coupling of sleep disturbance and negative affect during interepisode bipolar disorder. Ongoing monitoring of sleep-affect coupling may provide an important target for intervention in bipolar disorder.
View details for DOI 10.1037/a0028233
View details for Web of Science ID 000311527700007
View details for PubMedID 22845651
Social support and social strain in inter-episode bipolar disorder
2012; 14 (6): 628-640
This study focused on social support and social strain and their cross-sectional associations with instabilities in sleep and social rhythms in inter-episode bipolar disorder (BD).Thirty-five adults diagnosed with inter-episode BD type I and 38 healthy controls completed measures of perceived social support and social strain. Group differences in support and strain were examined. Within the BD group, instabilities in sleep and social rhythms were assessed with 28 days of daily diary and actigraphy. Correlation and regression analyses were used to examine cross-sectional and prospective associations between social support, social strain, instabilities in sleep and social rhythms, and mood symptoms.The BD group reported lower social support and higher social strain than the control group. Additionally, social strain was positively correlated with manic and depressive symptoms in the BD group. Furthermore, there was a cross-sectional association between social support and more stable sleep on actigraphy in the BD group, although social support did not predict future sleep instability.These results indicate that inter-episode BD is associated with deficient social support and elevated social strain compared to controls, and that this may be due to persistent inter-episode mood symptoms. Social strain may be particularly important given its association with manic and depressive symptoms. The results also raise the possibility that sleep instability is related to poor social support in BD.
View details for DOI 10.1111/j.1399-5618.2012.01049.x
View details for Web of Science ID 000308286800006
View details for PubMedID 22862999
Double trouble? The effects of sleep deprivation and chronotype on adolescent affect
JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY
2012; 53 (6): 660-667
Two understudied risk factors that have been linked to emotional difficulties in adolescence are chronotype and sleep deprivation. This study extended past research by using an experimental design to investigate the role of sleep deprivation and chronotype on emotion in adolescents. It was hypothesized that sleep deprivation and an evening chronotype would be associated with decreased positive affect (PA), increased negative affect (NA), and lower positivity ratios. Forty-seven healthy adolescents (aged 10-15 for girls, 11-16 for boys) participated in a sleep deprivation and a rested condition. A subsample of 24 adolescents was selected on the basis of extreme morningness or eveningness scores (based on outer quartiles of scores on the Children's Morningness-Eveningness Preferences Scale). PA and NA were measured using the Positive and Negative Affect Schedule for Children, and positivity ratios were calculated by dividing PA by NA. Participants reported less positive affect and lower positivity ratios when sleep deprived, relative to when rested. Evening chronotypes reported less positive affect and lower positivity ratios than morning chronotypes in both rested and sleep deprivation conditions. These findings extend previous research by suggesting that adolescents are adversely impacted by sleep deprivation, and that an evening chronotype might serve as a useful marker of emotional vulnerability. Early intervention and prevention strategies can focus on improving sleep and on using chronotherapy principles to reduce eveningness.
View details for DOI 10.1111/j.1469-7610.2011.02502.x
View details for Web of Science ID 000304087900007
View details for PubMedID 22188424
- Comparison between actigraphy, polysomnography and sleep diary in individuals with bipolar disorder Bipolar Disorders 2012; 14: 870-879
- Interventions for Sleep Disturbance in Bipolar Disorder. Sleep medicine and psychiatric illness. Lippincott Williams & Wilkins. 2012
The Effect of Sleep Deprivation on Vocal Expression of Emotion in Adolescents and Adults
2011; 34 (9): 1233-1241
Investigate the impact of sleep deprivation on vocal expression of emotion.Within-group repeated measures analysis involving sleep deprivation and rested conditions.Experimental laboratory setting.Fifty-five healthy participants (24 females), including 38 adolescents aged 11-15 y and 17 adults aged 30-60 y.A multimethod approach was used to examine vocal expression of emotion in interviews conducted at 22:30 and 06:30. On that night, participants slept a maximum of 2 h.Interviews were analyzed for vocal expression of emotion via computerized text analysis, human rater judgments, and computerized acoustic properties. Computerized text analysis and human rater judgments indicated decreases in positive emotion in all participants at 06:30 relative to 22:30, and adolescents displayed a significantly greater decrease in positive emotion via computerized text analysis relative to adults. Increases in negative emotion were observed among all participants using human rater judgments. Results for the computerized acoustic properties indicated decreases in pitch, bark energy (intensity) in certain high frequency bands, and vocal sharpness (reduction in high frequency bands > 1000 Hz).These findings support the importance of sleep for healthy emotional functioning in adults, and further suggest that adolescents are differentially vulnerable to the emotional consequences of sleep deprivation.
View details for DOI 10.5665/SLEEP.1246
View details for Web of Science ID 000294481700014
View details for PubMedID 21886361
- Hypersomnia in interepisode bipolar disorder: Does it have prognostic significance? Journal of Affective Disorders 2011; 132 (3): 438-44
Sleep Deprivation in Adolescents and Adults: Changes in Affect
2010; 10 (6): 831-841
The present study investigated the impact of sleep deprivation on several aspects of affective functioning in healthy participants selected from three different developmental periods: early adolescence (ages 10-13), midadolescence (ages 13-16), and adulthood (ages 30-60). Participants completed an affective functioning battery under conditions of sleep deprivation (a maximum of 6.5 hours total sleep time on the first night followed by a maximum of 2 hours total sleep time on the second night) and rest (approximately 7-8 hours total sleep time each night for two consecutive nights). Less positive affect was observed in the sleep-deprived, compared to rested, condition. This effect held for 9 of the 12 positive affect items on the PANAS-C. Participants also reported a greater increase in anxiety during a catastrophizing task and rated the likelihood of potential catastrophes as higher when sleep deprived, relative to when rested. Early adolescents appraised their main worry as more threatening when sleep deprived, relative to when rested. These results support and extend previous research underscoring the adverse affective consequences of sleep deprivation.
View details for DOI 10.1037/a0020138
View details for Web of Science ID 000286125600008
View details for PubMedID 21058849
- Hypersomnia across mood disorders: A review and synthesis Sleep Medicine Reviews 2009; 13: 275-285
- Cognitive mechanisms in chronic insomnia: Processes and prospects. Sleep Medicine Clinics 2009; 4 (4): 541-548
- Relationship between awareness of sleepiness and ability to predict sleep onset: Can drivers avoid falling asleep at the wheel? Sleep Medicine 2007; 9 (1): 71-79
- The impact of extra sleep on daytime alertness, vigilance, and mood. Sleep Medicine 2004; 5: 441-448