Experimental Sleep Manipulation and Pain Sensitivity in Healthy Adults: A Focused Review with Emphasis on Sleep Fragmentation

Background/Objectives: Experimental sleep loss can increase pain sensitivity, but sleep duration, continuity, and architecture are often altered simultaneously. This focused review compared pain outcomes across experimental sleep manipulations in healthy adults, with particular attention to sleep fragmentation (SF) and related awakening paradigms. Methods: PubMed and Web of Science Core Collection were searched through 16 September 2026; reference and citation checking identified additional reports. Eligible reports were synthesized narratively by sleep manipulation, design, pain modality, and dynamic pain-processing outcome. Designs included randomized or counterbalanced crossover studies, other within-participant or repeated-measures experiments, and parallel-group studies. Results: Fifty-two reports met the eligibility criteria. After overlapping and nested publications were consolidated, they formed 40 publication families comprising 41 provisionally distinct participant samples and approximately 1083 participants with analyzable data. Non-mutually exclusive categories comprised 21 reports of total sleep deprivation (TSD) or prolonged wakefulness, 17 of partial sleep restriction (PSR) or night-shift exposure, two directly evaluating SF, 10 evaluating related planned- or forced-awakening paradigms, six evaluating selective sleep-stage disruption, and two reports from provisionally distinct samples evaluating combined short and disrupted sleep. TSD and PSR showed the broadest evidence of increased pain sensitivity, but effects varied by modality and outcome. Both direct-SF reports identified at least one hyperalgesic outcome; the awakening literature was suggestive but contained multiple reports from shared samples. The combined protocol did not isolate sleep continuity from reduced duration. Conclusions: Disrupted sleep continuity may contribute to hyperalgesia, but an independent effect of SF remains uncertain because direct evidence is limited and awakening protocols often also change sleep duration, architecture, stress, or circadian timing.