{"id":"2bf43c61-21bd-5dd9-aed8-74a570793576","stable_key":"3279ff78-2460-5064-bfc0-3f2987af85a0:melatonin-phase-delay","predicate":"delays_when_timed_in_biological_morning","statement":"The phase-delay response peaked about eleven hours after dim-light melatonin onset.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"7b0f67d3-3f30-5b2d-9d11-682122230d3e","mechanism_event_label":"A different timing can move the clock in the opposite direction.","subject":{"id":"0f0bc1f1-d18d-5652-bc1d-98f61f7ab65c","slug":"melatonin","display_name":"Melatonin","entity_type_key":"small_molecule"},"object":{"id":"84849ca0-e0f3-5400-aaa0-e8d167462aa1","slug":"melatonin-circadian-phase","display_name":"Phase of the endogenous melatonin circadian rhythm","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"7b0f67d3-3f30-5b2d-9d11-682122230d3e","stable_key":"3279ff78-2460-5064-bfc0-3f2987af85a0:melatonin-phase-delay-event","event_type":"observed_intervention","label":"A different timing can move the clock in the opposite direction.","description":"The phase-delay response peaked about eleven hours after dim-light melatonin onset.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"0f0bc1f1-d18d-5652-bc1d-98f61f7ab65c","slug":"melatonin","display_name":"Melatonin","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"84849ca0-e0f3-5400-aaa0-e8d167462aa1","slug":"melatonin-circadian-phase","display_name":"Phase of the endogenous melatonin circadian rhythm","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/melatonin-research/18006583.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"9eb1409f6e4c58eadfaf1554930378e03860dc9dc1201de6d104b6de784758ea\", \"start_char\": 0, \"end_char\": 1518, \"text_sha256\": \"9eb1409f6e4c58eadfaf1554930378e03860dc9dc1201de6d104b6de784758ea\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Double-blind counterbalanced phase-response experiment","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"3 mg once daily for three days at different circadian times; dim-light onset measured","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Timing is relative to individual biological phase, not a universal clock hour. This experimental schedule is not a dosing instruction.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Melatonin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"melatonin","display_name":"Melatonin","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"27 healthy young adults","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A different timing can move the clock in the opposite direction.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[melatonin-p18006583] A three pulse phase response curve to three milligrams of melatonin in humans. (2008). https://pubmed.ncbi.nlm.nih.gov/18006583/ DOI: 10.1113/jphysiol.2007.143180","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Circadian melatonin timing","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"365a1412-78d8-5a0a-9072-d1d8dd606aeb","evidence_kind":"source_excerpt","locator":"Lines 851-862","start_line":851,"end_line":862,"excerpt":"### melatonin-phase-delay\nThe phase-delay response peaked about eleven hours after dim-light melatonin onset.\nCondition category: normal\nnutrient_topic: Melatonin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A different timing can move the clock in the opposite direction.\norganism: 27 healthy young adults\ntissue_or_cell_type: Circadian melatonin timing\nexperimental_model: Double-blind counterbalanced phase-response experiment\nlimitations: Timing is relative to individual biological phase, not a universal clock hour. This experimental schedule is not a dosing instruction.\nexposure: 3 mg once daily for three days at different circadian times; dim-light onset measured\nevidence_span: {\"source_cache\": \"artifacts/melatonin-research/18006583.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"9eb1409f6e4c58eadfaf1554930378e03860dc9dc1201de6d104b6de784758ea\", \"start_char\": 0, \"end_char\": 1518, \"text_sha256\": \"9eb1409f6e4c58eadfaf1554930378e03860dc9dc1201de6d104b6de784758ea\"}\n[melatonin-p18006583] A three pulse phase response curve to three milligrams of melatonin in humans. (2008). https://pubmed.ncbi.nlm.nih.gov/18006583/ DOI: 10.1113/jphysiol.2007.143180","model_system":"Double-blind counterbalanced phase-response experiment","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [melatonin-p18006583] A three pulse phase response curve to three milligrams of melatonin in humans. (2008). https://pubmed.ncbi.nlm.nih.gov/18006583/ DOI: 10.1113/jphysiol.2007.143180","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"bab588de-d217-5038-9c8b-b41222eba08b","stable_key":"import-3279ff78-2460-5064-bfc0-3f2987af85a0","title":"Melatonin: synthesis, receptors, circadian timing and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"ff4f279d263f95a69da8e7e8a6c6318ab6ba1b55254dbbda1bfa9ce437e1db80","revision_id":"0318eef8-ff38-513e-8ffa-458146ca5e77","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}