Background: Decreased sound tolerance (DST) is an increased sensitivity to sound at levels that would not bother most people. DST is highly prevalent in autistic adults; however, the extent to which DST differs across autistic and non-autistic adults is uncertain. This study explores multiple domains of DST symptoms and the severity of DST symptoms, as well as the behavioral reactions and coping strategies adopted to manage DST in both autistic and non-autistic adults. Lastly relationships between DST, autism characteristics, mental health, and quality of life were explored.Methods: This study used online surveys to investigate the characteristics of DST in 77 autistic and 128 non-autistic adults who self-report DST, as well as the relationship between DST and autistic characteristics, mental health, and quality of life.Results: The results of this study indicated that clinically relevant misophonia, an aversion to specific sounds, was more prevalent in the sample of autistic adults who self-reported DST. Similarly, clinically relevant hyperacusis, a reduced tolerance to everyday sounds at volumes that would not be distressing to most people, was also more prevalent in the sample of autistic adults who self-reported DST. Across the entire sample, misophonia symptoms were associated with more autistic traits and higher anxiety, whereas hyperacusis symptom severity was associated with more autistic traits, higher anxiety and depression symptoms, and poorer quality of life.Conclusion: Although clinical cases of misophonia and hyperacusis were more prevalent in our sample of autistic adults who self-reported DST, these forms of DST may be related in similar ways to mental health and quality of life of both autistic and non-autistic adults. Future work should focus on differentiating the subtypes of DST to facilitate the development of treatments that specifically target the symptoms of each subtype (i.e., misophonia, and hyperacusis) rather than treating DST as a homogeneous problem. Community Brief Why is this an important issue? Many autistic adults find sounds to be distressing. However, we are unsure whether these experiences with sound are similar to the experiences of non-autistic adults. We also don't know if the distress caused by sound has similar effects on anxiety, depression, and quality of life for autistic and non-autistic adults. What was the purpose of this study? The purpose of this study was to better understand how sounds influence autistic and non-autistic adults who report sounds to be distressing. Specifically we were interested in the types of sounds and general features of sounds that are distressing. We also wanted to know how these adults react to sound and what they try to do to reduce negative reactions to sound. We were interested in how the distress created by sound might be related to autism characteristics, anxiety, depression, and quality of life. What did the researchers do? We had 77 autistic and 94 non-autistic adults who self-reported a decreased tolerance to sound fill out questionnaires online. These questionnaires asked about experiences with sound, autistic characteristics, anxiety, depression, and quality of life. What were the results of the study? The results indicated that misophonia, a dislike of specific trigger sounds, was worse in autistic adults. Hyperacusis, or suffering caused by everyday sounds at a loudness that does not bother most people, was also worse in autistic adults. Misophonia symptoms were related to anxiety in both autistic and non-autistic adults. Hyperacusis symptoms were related to autism characteristics, anxiety, and depression, and a lower quality of life in both autistic and non-autistic adults. What do these findings add to what was already known? These findings tell us that the kinds of sounds that are troublesome and the reactions adults have to sound are qualitatively similar for autistic and non-autistic adults, with autistic adults having more severe symptoms. These findings also tell us that decreased sound tolerance may affect mental health and quality of life. However, as we looked at associations between different variables, we cannot say that decreased sound tolerance is causing poor mental health and reduced quality of life; rather these findings just reveal that they are related. What are potential weaknesses in the study? Our data were collected online, so we could not make sure that our autistic participants had official diagnoses. Online collection also made us unable to test participants' hearing. Most of our sample was female. We are unsure if this is because more females find sound distressing, or more females are willing to complete online surveys. Lastly, because participants were describing their trouble with sound, we were not objectively measuring reactions to sound; it is possible that the observed findings might be the result of how people chose to describe their experiences. The instruments used to measure hyperacusis and misophonia have not been validated on autistic samples. Future work using measures validated on autistic samples could reveal different patterns of results. How will these findings help autistic adults now or in the future? These findings explain the types and features of sounds that cause the most trouble for autistic people. These findings also suggest that sound may have a big effect on the mental health and quality of life of autistic people. As such, these findings provide important information that can be used to help people to create more sensory-friendly environments that will be of great benefit to autistic people with sound sensitivities.
