A recent study in China exposed mice to unpredictable stress during the day and played music to them at night. The results indicated that listening to music completely prevented the development of anxiety- and depression-like behaviors in these mice. Biochemical parameters examined further supported these findings. The paper was published in Translational Psychiatry.
Depression and anxiety are two distinct yet often interrelated mental health conditions. Depression typically manifests as persistent feelings of sadness, hopelessness, and a lack of interest or pleasure in activities. It is frequently accompanied by physical symptoms such as changes in sleep and appetite. Anxiety, on the other hand, is characterized by excessive worry, nervousness, and fear, often leading to physical symptoms like an increased heart rate, sweating, and restlessness. While depression mainly affects one’s mood and outlook on life, anxiety is largely a response to stress and perceived threats.
Both of these conditions can significantly impair an individual’s daily functioning and quality of life. There has been a strong increase in their incidence worldwide in the past several decades. Researchers have been attributing this to increased social pressure and an accelerated pace of life, but the exact cause-and-effect mechanisms through which these conditions develop remain unknown.
Standard treatments for depression and anxiety include medication and psychotherapy, but their effectiveness is far from 100%. Over 30% of individuals with these disorders do not respond to standard treatments and are diagnosed with treatment-resistant forms of the disorders. That is why researchers are constantly looking for novel ways to cure or at least improve symptoms of these disorders. One of the things they look to is music.
Previous research has suggested that listening to music can be beneficial in various conditions, but evidence of its effectiveness in treating depression and anxiety is limited. To explore this, study author Qiang Fu and his colleagues conducted an experiment on mice. They aimed to determine if listening to music could protect mice from the negative psychological and physiological effects of chronic exposure to mild unpredictable stress.
The study was conducted on 36 male mice purchased from the Fang Yuanyuan Breeding Farm in Beijing, China. The mice were housed in enclosures maintained at 23°C under a 12-hour light/dark cycle, with lights on from 8 in the morning until 8 in the evening. They had free access to standard mouse food and water.
The researchers divided the mice into four groups. One group was exposed to chronic mild unpredictable stress, another listened to music, the third group experienced both stress and music, and the fourth group served as a control, living normally during the study. The stress groups were subjected to various stressors like restraint, tilting their cage by 45 degrees, wet bedding, food and water deprivation, tail nipping, cold water swimming, and inversion of the light cycle. Mice were housed individually, and those in the stress groups were exposed to three different stressors daily.
The mice in the music groups listened to music for 90 minutes each evening between 8:30 and 10:00 PM. The music played randomly from a playlist of 25 pieces previously used in auditory stimulation experiments, comprising a mix of Eastern and Western instrumental and vocal compositions.
After 28 days of stress and music treatment, the researchers conducted behavioral tests on the mice. These tests included the sucrose preference test (assessing anhedonia), the open field test (measuring exploratory behavior), tail suspension test (indicative of depression-like behavior), novelty suppressed feeding (measuring anxiety-like behavior), and the elevated plus maze (another test for anxiety-like behavior).
Results of behavioral tests showed that mice that were subjected to stress but also listened to music showed much lower levels of anxiety- and depression-like behaviors compared to mice that were only subjected to stress conditions. The behavior of mice exposed to both stress and music closely resembled that of the unstressed mice. Only the behavior of mice that were only subjected to stress stood out from the other groups.
Additionally, the study authors performed various biochemical analyses on the mice. They found that music prevented oxidative stress in the serum and brain tissues. Biochemical indicators of oxidative stress were elevated in mice exposed only to stress, but remained normal in those also listening to music. Similarly, music seemed to prevent inflammation in the serum and brain of stressed mice, mitigated neuronal death, promoted new neuron creation, and protected against a range of adverse biochemical changes.
“In conclusion, the neural mechanism by which music prevents anxiety- or depression-like behavior may be that music protects against the disruption caused by oxidative stress and increase in inflammation levels caused by severe stress in mice and prevents the HPA axis [hypothalamus-pituitary-adrenal axis, a neural mechanism controlling reaction to stress and regulating many body processes] from releasing large amounts of corticosterone due to overexcitation, which leads to the downregulation of BDNF [brain-derived neurotrophic factor, a protein that plays a crucial role in promoting the survival, growth, and maintenance of neurons in the nervous system]. Finally, it protects neurons from loss and maintains homeostasis,” the study authors concluded.
The study sheds light on the protective effects of music in mice exposed to stress. However, it should be noted that the study was conducted on mice and not on humans. While mice and humans share many physiological similarities, they are also vastly different in many other aspects. Studies on humans might not produce equal results.
The paper, “Music prevents stress-induced depression and anxiety-like behavior in mice”, was authored by Qiang Fu, Rui Qiu, Lei Chen, Yuewen Chen, Wen Qi, and Yong Cheng.
