The theory of lonely evolution suggests that human sense of belonging is crucial for survival, and the inability to satisfy this sense of belonging can pose a threat to an individual's ability to survive. Psychologists from institutions such as the University of Arizona and Oregon State University have found that loneliness can make people more susceptible to nightmares. This discovery is of great significance, as loneliness and sleep disorders are not only serious public health issues, but also closely associated with an increased risk of heart disease, stroke, and premature death. The team surveyed 1609 Americans aged 18 to 81. The analysis results show that loneliness can predict the frequency and intensity of nightmares. Stress, excessive awakening, and rumination mediate the relationship between loneliness and nightmare frequency. This indicates that lonely people feel immense pressure, have increased rumination, and heightened alertness, which increases the likelihood of having nightmares. Researchers explain that social connections are a reflection of human core needs, and when these needs are not met, individuals will suffer physical and mental pain. When the needs of interpersonal relationships are not met, loneliness as an evolutionary mechanism can also alert individuals to this deficiency. Loneliness is a common mental health condition that can seriously affect health, leading to a series of diseases including sleep disorders, and nightmares are a manifestation of sleep quality being affected. The research findings published in the Journal of Psychology suggest that this discovery not only deepens people's understanding of the relationship between loneliness and nightmares, but also provides new insights into the widespread impact of loneliness on health, emphasizing the important role of social connections in maintaining physical and mental health. (New Society)