The Association Between Parasomnias and Feelings of
Stress, Anxiety, and Depression
Ryann Gollings, Thiel College
Abstract: The purpose of this study is to examine the association between parasomnias, specifically sleepwalking and sleep talking, and feelings of stress, anxiety, and depression. The current research literature on this potential association is surprisingly sparse. The literature that does exist is mostly in the form of case studies, rather than more general research on healthy samples of adults. It remains to be understood why adults experience parasomnias. There has been some speculation about potential triggers, such as stress and anxiety, but there is little empirical data to support these speculations. This study used a mixed-methods research design with both qualitative and quantitative measures to determine whether feelings of stress, anxiety, and depression might be related to, or trigger, experiences of parasomnias in college-aged adults. The results of the qualitative study showed that as levels of stress, anxiety, and depression increased, parasomnia scores increased. For the qualitative study, most of the participants stated that they believed stress, anxiety, and depression could be a potential trigger for their parasomnias. This study fills that gap in research and can be used to help those who suffer from parasomnias to better understand how to control their circumstances.
The Association Between Parasomnias and Feelings of Stress, Anxiety, and Depression
Nobody knows what to expect when they fall asleep at night. Will they have a good dream or a nightmare? When they get up in the morning, will their partner tell them about a conversation they had that they do not remember at all? Sleep is a very important part of everyone’s daily life. It is suggested that adults get 7-9 hours of restful sleep every night to be able to tackle a days’ worth of tasks (sleepfoundation.org). Many people struggle to not only get that amount of sleep, but also to ensure that it will be a good night’s sleep. There is surprisingly little research that examines sleep disorders and what the triggers of them may be. Research in the areas of parasomnia, stress, anxiety, and depression will be reviewed as a foundation for the current study. This study will look at the association between the experience of parasomnias and feelings of stress, anxiety, and depression.
There are many odd occurrences that can happen during sleep. Parasomnias are sleep disorders that are abnormal behaviors or physiological events that can happen during the transitional stage between sleep and waking (dictionary.apa.org). Sleepwalking typically occurs more often in children, but usually stops as they get older. However, in about 2-4% of people, sleepwalking still occurs into adulthood or starts in adulthood (Bušková et al., 2015). Sleep talking seems to be more common. As many as 66.8% of adults have reported talking in their sleep at some point in their lives, but only 6.3% talk in their sleep at least once a week (Arnulf, 2017). There is not much known about any particular triggers for these types of parasomnias. There has been some speculation, such as sleep deprivation or stressful events. (Bušková et al., 2015).
Sleep is imperative to keep people well rested and energized for their everyday tasks. However, with disruptions like sleepwalking or sleep talking, it can have a negative impact on these individuals. Sometimes, there is an association between sleepwalking in adulthood and some dangerous behaviors that can result in injury for either the sleepwalker themselves or others around them (Bušková et al., 2015). With some recent medical advancements, such as the electroencephalogram, it has significantly helped with sleep research to understand the different stages of sleep and sleep patterns (Umanath, Sarezky & Finger, 2011).
Umanath, Sarezky, and Finger (2011) compiled the history of sleepwalking through many forms, such as medicine, arts, and the law. The authors first discuss how the medical community has viewed it in the past and several potential ideas for the cause of sleepwalking and how to prevent it, even as much so as to categorize them as epilepsy. The authors then moved on to the arts where they discuss how sleepwalking was interpreted by others and how they used sleepwalking to evoke certain emotions, or ideas. An example they used was in Shakespeare’s Macbeth where Lady Macbeth was seen sleepwalking to show guilt, while others showed sleepwalking as a disease. Lastly, the authors discussed sleepwalking in relation to the law. Through their other findings with medicine and the arts, there seemed to be much to discover about sleepwalking, but it seems as though courts and lawyers have made decisions about sleepwalkers. The conversation surrounding sleepwalking and the law is whether or not someone can be held responsible for their actions while sleepwalking. The authors found that typically the courts and lawyers have said that individuals that commit crimes while sleepwalking are not responsible for these actions.
Researchers Bušková, Piško, Pastorek, and Šonka (2015) conducted a study to look at the characteristics of sleepwalking in adults. The researchers aimed to determine if the severity of sleepwalking depended on how long the participant had the disorder, if there are any factors that contribute to sleepwalking progressing into adulthood, and if more severe cases of sleepwalking cause more disruptions in their sleep. To obtain data for this study, the researchers had fifty-two patients between 19-63 years old that had been diagnosed with sleepwalking. The participants were interviewed by a sleep specialist to assess their medical history, sleep complaints, family history, sleepwalking episodes, and potential factors that could have contributed to their onset of sleepwalking. The participants then went through a two-night video recording. The results of the study showed that the onset of sleepwalking on average happened around 17.9 years old and about 46% of participants had been sleepwalking since their childhood. About 54% of participants reported dangerous behavior while sleepwalking. During the sleep study, 59.6% of participants showed at least one abnormal behavior, but was not as severe as they had reported while they were at home. The outcome of this study implied that there were many factors that were reported to be potential triggers of sleepwalking, and sleepwalking during adulthood could be associated with dangerous behaviors.
Branching further out, Lopez, Jaussent, and Dauvilliers (2015) conducted a study to examine the association between chronic pain in sleepwalkers. The aim of their research was to evaluate the frequency of pain in sleepwalkers compared to control participants. To obtain data for this study, the researchers had one hundred adults that were diagnosed with sleepwalking 18-59 years old. All sleepwalking participants went through a one-night sleep recording. All participants underwent an interview to collect data on sleep characteristics, and pain problems. Pain was examined by a clinician and a questionnaire was filled out where they were asked about chronic pain symptoms. The researchers also examined dangerous sleepwalking behaviors. The results of the study showed that sleepwalkers more frequently experienced daytime sleepiness, depressive symptoms, and insomnia symptoms compared to the control group. Two participants met the criteria for major depressive disorder and one participant for generalized anxiety disorder. The outcome of this study showed that the correlation between pain and sleep is still unclear, but this research discussed how sleepwalking patients complain of pain frequently while they are awake, but do not experience the pain while sleepwalking.
Arnulf et. al. (2017) conducted a study about the syntax and semantics of sleep talking. The aim of this study was to analyze speech during sleep. To obtain data for this study, the researchers collected the verbal utterances of the 232 participants. The participants were also interviewed to assess their history, sleep disorders, and use of foreign language while sleep talking. The results of this study showed that of the 883 utterances they collected, most were non-verbal noises including mumbles, laughs, cries, etc. The researchers then broke down the speech episodes and looked into tone, word analysis, verbal abuse, silences for turn taking, and even what languages are used during sleep talking. The outcome of this study showed the differences between noise utterances and actual speech produced.
Hublin, Kaprio, Partinen, and Koskenvuo (1998) conducted a study on sleep talking in twins. The aim of this study was to understand the genetic influence of sleep talking and its association with psychiatric disorders. To obtain data for this study many sets of twins were asked to both answer a questionnaire about sleep and sleep talking. The results of this study showed that frequent sleep talking was significantly associated with psychiatric comorbidity. The outcome of this study showed that sleep talking is common and there was no difference in how often it occurs in monozygotic and dizygotic twins. They did find that genetics can play a role in whether or not someone sleep talks or not, but the specific genes have not been identified.
Stress, Anxiety, and Depression
There is little research focused on how stress, anxiety, and depression can trigger parasomnias. However, researchers Trivedi and Joshipura (2015) conducted a case study on an 18-year-old female who was experiencing a few episodes of sleepwalking triggered by anxiety. The Beck Anxiety inventory was used to measure her anxiety levels. The patient was treated with Cognitive Behavioral Therapy and through this treatment it was found that the patient was stressed with a lot of typical stressors of an 18-year-old and was beginning to handle those stressors poorly. After many therapy sessions, it was determined that she had many underlying stressors that resulted in a Generalized Anxiety Disorder and with some medication and time, she was able to stop sleepwalking. The outcome of this case study showed that Generalized Anxiety Disorder could be a trigger for sleepwalking.
After reviewing the research on parasomnias, sleepwalking, sleep talking, stress, anxiety, and depression, it is clear that there is a need for research in this area to establish the potential relationship between them. The purpose of this study is to examine the relationship between parasomnias and stress, anxiety, and depression to have more information on potential triggers for sleepwalking and sleep talking. This research will help to further an understanding of parasomnias and what can trigger them to occur. I hypothesize that the more feelings of stress, anxiety, and depression an individual has the more frequent and severe their parasomnias will be. This hypothesis is based on the previous research that shows how daily life stressors, emotions and diagnoses can impact sleep habits and occurrences.
The participants in this study were 107 college-aged individuals. The participants were randomly recruited to participate in the survey portion of the study on a voluntary basis through their email addresses. Participants ranged in age from 18 to 24 years of age with the mean age being 19.72 (SD=1.37). Of the 107 participants, 20.6% were male and 79.4% were female. The participants were 90.7% Non-Hispanic White or Caucasian.
The participants who agreed to be contacted for an interview through the survey were recruited to answer interview questions. This portion of the study was conducted on 9 participants, who ranged in age from 18 to 24 years of age. Of the 9 participants, 22% were male and 78% were female. The participants were 100% Non-Hispanic White or Caucasian. To preserve anonymity in the reporting of results, these 9 participants were assigned letters (Participant A-I).
For the quantitative part of the study, participants were asked to complete a survey compiled of questions based on four scales. The participants answered questions from the “Munich Parasomnia Scale” (Fulda et al., 2008), the “Perceived Stress Scale” (Cohen, Kamarck, & Mermelstein, 1983), the “Beck Anxiety Inventory” (Beck et al., 1988), and the “Beck Depression Inventory” (Beck et al, 1961).
The parasomnia scale was designed to measure the severity and frequency of parasomnias in the participant. This scale had 14 questions asking how often the participant experienced each of the behaviors on a Likert scale from “behavior never observed by me or others” to “very frequently – every or almost every night”. If participants stated that they had experienced that behavior, they were asked a follow up question about how they knew they exhibited that behavior from “self-observation” or “observed by others”. The scale was scored from 0 – “behavior never observed by me or others” to 6 – “very frequently – every or almost every night” for each question. For example, the participants were asked if they exhibited “teeth grinding during the night”, “waking with severe anxiety and possibly, screaming, with no recollection of a dream”, and “have you ever done what you dreamt, e.g. gesticulating or lashing out”.
The stress scale was designed to measure levels of stress in participants. This scale had 10 questions asking in the past month how often they had felt or thought a certain way on a Likert scale from “never” to “very often”. The scale was scored from 0 – “never” to 4 – “very often” for each question. For example, participants were asked in the last month how often they felt “confident about your ability to handle your personal problems”, “that you were on top of things”, and “that you were unable to control the important things in your life”.
The anxiety inventory was designed to measure levels of anxiety in participants. This scale had 21 statements asking in the past month how much each of the symptoms has bothered the participant on a Likert scale from “not at all” to “severely – it bothered me a lot”. The scale was scored from 0 – “not at all” to 4 – “severely – it bothered me a lot” for each symptom. For example, participants were asked how much in the last month they had been bothered by symptoms like “numbness and tingling”, “fear of losing control”, and “terrified or afraid”.
The depression inventory was designed to measure levels of depression in participants. This scale also had 21 questions where the participants were asked to answer between four options that best fit them. For example, one question asked the participants to choose between “I do not feel sad.”, “I feel sad”, “I am sad all the time and I can’t snap out of it.”, and “I am so sad and unhappy that I can’t stand it.”. Each question was scored on a scale from 0 to 3. The first option was always scored the lowest for the least severity and the fourth option was always scored the highest for the most severity.
For the qualitative part of the study, participants were asked a series of 10 interview questions about parasomnias, and then how they felt their parasomnias relate to stress, anxiety, and depression. Participants responded open-endedly and the interviewer took notes of their responses. Specifically, participants were asked “How often do you experience parasomnias?”, “What are some things you do in your sleep?”, “Can you describe your parasomnias?”, “How did you find out that you experience parasomnias?”, “What do you remember before or after an episode of your parasomnias?”, “Have you noticed any patterns in your parasomnias? If so, what are they?”, “Why do you think you experience parasomnias?”, “Do you think stress increases your experience of parasomnias?”, “Do you think anxiety increases your experience of parasomnias?”, and “Do you think a depressive mood increases your experience of parasomnias?”.
The research design of this study was non-experimental. Both a quantitative method (survey) and a qualitative method (interview) were used to study the relationship between parasomnias and participant’s feelings of stress, anxiety, and depression. The explanatory variables were stress, anxiety, and depression. The response variable was number of parasomnias.
Participants were asked to fill out an online survey. Before beginning the survey, there was an online informed consent form in compliance with the American Psychological Association (APA) regulations. Once participants read the informed consent form, the participants were directed to the survey. Once the survey was completed, they were directed to a debriefing form where the participants were given resources if any questions felt triggering. The survey took about 15-20 minutes to complete.
Participants who consented to be contacted for an interview were reviewed to see if they had parasomnias, and those that did were contacted for interview. The location of the interviews was agreed upon by the researcher and each individual participant in a socially distanced area. The interview was structured around ten questions that were asked of each participant and the responses were recorded by the interviewer’s notes. The interview time varied according to the length of the participants responses.
Before testing the study hypothesis, the data was analyzed using descriptive statistics. The main study variables included parasomnias, stress, anxiety, and depression. For each variable. The overall mean and standard deviation were calculated. The main study hypothesis was tested using inferential statistics. I hypothesized that the more feelings of stress, anxiety, and depression an individual reports, the more frequent and severe their parasomnias will be. Three Pearson’s correlational analyses and three analysis of variance (ANOVA) inferential tests were conducted. In each test, the response variable was parasomnias and the explanatory variables were stress, anxiety, and depression.
For the survey measure of parasomnias, the overall mean score was 21.11 and the standard deviation was 11.56. The range of scores given by the participants was from 2-56 on a scale of 0-84. For the survey measures of stress, the overall mean stress level was 20.51 and the standard deviation was 7.68. The range of scores given by the participants was from 5-37 on a scale of 0-40. For the survey measures of anxiety, the overall mean anxiety level was 15.71 and the standard deviation was 11.50. The range of scores given by the participants was from 0-52 on a scale of 0-63. For the survey measures of depression, the overall mean depression level was 13.13 and the standard deviation was 10.91. The range of scores given by the participants was from 0-47 on a scale of 0-63.
There was a statistically significant and moderately positive correlation between parasomnias and stress, r (107) =.301, p=.002. The significant positive correlation shows that as stress levels increase, the parasomnias score also increases. The results suggest that 9.1% of the variance in parasomnias can be explained by the amount of stress the participant experiences. Because this test was significant, the null hypothesis was rejected, and the alternate hypothesis was accepted. The alternate hypothesis is that there is a relationship between levels of stress and parasomnias score.
There was a statistically significant and strong positive correlation between parasomnias and anxiety, r (107) =.401, p=.000. The significant positive correlation shows that as anxiety levels increase, the parasomnias score also increases. The results suggest that 16.1% of the variance in parasomnias can be explained by the amount of anxiety the participant experiences. Because this test was significant, the null hypothesis was rejected, and the alternate hypothesis was accepted. The alternate hypothesis is that there is a relationship between levels of anxiety and parasomnias score.
There was a statistically significant and weak positive correlation between parasomnias and depression, r (107) =.205, p=.034. The significant positive correlation shows that as depression levels increase, the parasomnias score also increases. The results suggest that 4.2% of the variance in parasomnias can be explained by the amount of anxiety the participant has. Because this test was significant, the null hypothesis was rejected, and the alternate hypothesis was accepted. The alternate hypothesis is that there is a relationship between levels of depression and parasomnias score.
To further examine these relationships, the explanatory variables (stress, anxiety, and depression) were split into three groups. These groups placed participants in a low, medium, or high stress, anxiety, and depression category. The parasomnias score was then compared between these groups using analysis of variance (ANOVA).
An analysis of variance (ANOVA) was conducted to examine the relationship between levels of stress and parasomnias score. The ANOVA was significant, suggesting that there was a relationship between levels of stress and frequency of parasomnias, F (2,104) =3.46, p=.035. The mean parasomnias score for the low stress group was 17.2 (SD=7.48), the mean parasomnias score for the medium stress group was 22.2 (SD=11.38), and the mean parasomnias score for the high stress group was 24.13 (SD=14.38). Post-hoc comparisons were conducted to determine where the significant differences existed in pairs of the explanatory variable groupings. The Tukey post-hoc test revealed significant differences in parasomnias scores between low levels of stress and high levels of stress groups only. All other group comparisons were not significantly different. By examining the bar graph (Figure 1), it appears that participants with higher levels of stress had a higher parasomnias score.
An analysis of variance (ANOVA) was conducted to examine the relationship between levels of anxiety and parasomnias score. The ANOVA was significant, suggesting that there was a relationship between levels of stress and frequency of parasomnias, F (2, 104) = 13.94, p=.000. The mean parasomnias score for the low anxiety group was 15.97 (SD=7.67), the mean parasomnias score for the medium anxiety group was 19.42 (SD=8.74), and the mean parasomnias score for the high anxiety group was 28.43 (SD=13.83). Post-hoc comparisons were conducted to determine where the significant differences existed in pairs of the explanatory variable groupings. The Tukey post-hoc test revealed significant differences in parasomnias score between low levels of anxiety and high levels of anxiety groups and between medium levels of anxiety and high levels of anxiety groups. All other group comparisons were not significantly different. By examining the bar graph (Figure 2), it appears that participants with higher levels of anxiety had a higher parasomnias score.
An analysis of variance (ANOVA) was conducted to examine the relationship between levels of depression and parasomnias score. The ANOVA was significant, suggesting that there was a relationship between levels of depression and parasomnias score, F (2, 104) =3.51, p=.033. The mean parasomnias score for the low depression group was 17.43 (SD=9.26), the mean parasomnias score for the medium depression group was 21.61 (SD=10.45), and the mean parasomnias score for the high depression group was 24.35 (SD=13.64). Post-hoc comparisons were conducted to determine where the significant differences existed in pairs of the explanatory variable groupings. The Tukey post-hoc test revealed significant differences in parasomnias scores between low levels of depression and high levels of depression groups only. All other group comparisons were not significantly different. By examining the bar graph (Figure 3), it appears that participants with higher levels of depression had a higher parasomnias score.
At the beginning of the interviews, stress, anxiety, or depression were not brought up to get a good understanding of each individual’s parasomnias before relating them to the variables of interest. However, some participants brought up these topics on their own, correlating the two without knowing it was going to be asked about later. I begin with this observation because it provides evidence for the hypothesis that parasomnias and stress, anxiety, and depression are related.
When asking participants about their parasomnias specifically, most spoke of sleepwalking and sleep talking over all other parasomnias. A few participants discussed nightmares and night terrors as well. A few people stated that their parasomnias occurred quite often; however, most participants stated that it either happened when they were younger or does not happen as frequently anymore. Many participants found out that they had these parasomnias from family members, such as parents or siblings. Some participants also reported that significant others told them about their parasomnias, and that they occurred more often than they had previously believed.
Many participants did not know why or had never thought about why they experienced parasomnias. Some speculations were given when asked. Participant A stated many possibilities such as bad eating habits or punishments for a past life explaining their experience of nightmares. Participant G stated that their parasomnias started after a traumatic incident in their life. Participant E brought up the thought that they could be triggered after watching a scary movie. When asked about why the participants believe they experience parasomnias, two of the nine participants stated that stress could potentially be a factor contributing to their parasomnias. However, when asked specifically about whether they believe stress increases their experience of parasomnias or not, seven of the nine participants stated either “probably – yes” or “definitely”. The other two participants said that it was possible, but they were unsure.
The participants were then asked a similar question about whether or not anxiety increased their experience of parasomnias, Interestingly, the same seven participants also stated that anxiety was a possible explanation for their parasomnias. The last question of the interviews was similar to the previous two, asking if a depressive mood increased their experiences of parasomnias and there was a significant change in answers. Five of the participants stuck with the same answer that it was a “potential explanation”. Participant E stated that a depressive mood was a “possible explanation, but it did not seem to be as much of an explanation as the other two”. Participant I stated that they sleep more often when they are in a depressive mood so there is more opportunity for their parasomnias to occur.
The results of this study found that there was a significant difference in parasomnia scores when looking at different levels of stress, anxiety, and depression experienced by the participants. Even though they were all significant, positive relationships, the results of the quantitative analyses between stress, anxiety, and depression differed. Anxiety had the highest mean, then stress, and then depression with the lowest mean. The ANOVA tests showed that with higher levels of stress, anxiety, and depression, the participants’ parasomnias scores were also higher. In the qualitative analyses, the majority of participants who had experienced some sort of parasomnia stated that they believed stress, anxiety, and depression increased their experience of parasomnias. The results of this study supported the hypothesis that the more feelings of stress, anxiety, and depression an individual has the more frequent and severe their parasomnias will be.
It must be acknowledged that this study was not conducted without limitations. This study was only done on college-aged students at Thiel College. If this study were done at other schools or with a different age group, the results may have been different. Being that the participants were from Thiel College, the majority of the population at Thiel is Non-Hispanic White or Caucasian, so most of the participants were as well. In both the survey and the interviews, the majority of participants were female. Although there were some male participants who experienced parasomnias, not many wanted to be interviewed.
The qualitative part of the study was done using interviews. However, there were many limitations with this aspect since there was an outbreak of COVID-19 cases on campus. Because of this outbreak during the study period, some participants were in quarantine so we could not meet in person for their interview. Instead, the decision to have the interviews conducted on Zoom was made. However, it is possible that the responses for the interview questions were shortened because people are not accustomed to one-on-one meetings online and were potentially more uncomfortable. Further, this semester has been very difficult for college students all over America, no matter how their classes are being held, so this could also be an explanation for why the participants were short with some of their interview answers. The goal of the interview was to get a more detailed explanation for sleepwalking and sleep talking triggers, which was only partly accomplished with participants’ brief responses. It is also possible that many people do not recall exact moments of stress, anxiety, and depression that would have triggered their parasomnias, making it hard to gather this type of information.
The quantitative part of the study had a few limitations when it came to the survey itself. Although the survey used validated scales, the parasomnias scale had only two questions about sleepwalking and sleep talking specifically. There were also no open-ended questions on the survey for participants to give specific examples, like the interviews. This means that the participants were not able to report specific moments of stress, anxiety, and depression, and how they potentially trigger parasomnias on the survey.
Although this study supported the hypothesis and had statistically significant results, there are many future directions for this topic area. For instance, it would be interesting to repeat this study with participants who have severe parasomnias. Seeing how the results differ for stress, anxiety, and depression would be intriguing with a higher parasomnia score. In addition to this, looking at specific items in the stress, anxiety, and depression scales could show a different impact on parasomnias, or even specifically sleepwalking and/or sleep talking. For example, one item on the depression scale asks about feeling disappointed in themselves. It might be that feelings of disappointment have a greater influence of sleepwalking or sleep talking than depression overall.
It would also be interesting for other researchers to conduct a sleep study on participants who have severe parasomnias. In a sleep study, participants could be thoroughly investigated to truly understand all parasomnias that are present in the participants. Since people do not always know what parasomnias they have or do not recall ever having them, it is difficult to find validity in their responses. Researchers could also examine stress, anxiety, and depression in a more scientific way by looking at brain activity and hormone balances. Rather than having participants self-report these variables, brain scans would be able to give a more valid result.
Another possible direction for this topic area could be an actual experiment. Researchers could induce daily stress, anxiety, and a depressive mood on the participants and then perform a sleep study to see if specific triggers of stress, anxiety, or a depressive mood impact the participants parasomnias. This kind of research would test the hypothesis further and tackle some of the limitations for the current study. An experiment like this would allow for the researchers to understand with more certainty the triggers of stress, anxiety, or depression and whether or not they impact the frequency and severity of parasomnias.
The results of this study are important pieces to help us begin to understand the correlation between parasomnias and stress, anxiety, and depression. Understanding potential triggers for parasomnias can guide us in finding ways to lessen them and to allow for people to have more restful sleep. When sleep is interrupted whether a person knows it is occurring or not, it can be harmful for their overall health. This study helped to close the gap of knowledge about possible triggers for parasomnias on a more general level. Research correlating parasomnias and stress, anxiety, and depression is very sparse and has only been conducted in case studies. Branching out to a broader population and identifying these possible triggers will allow research to look into possible treatments, or solutions, to avoid these triggers and reduce the frequency and/or severity of parasomnias.
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