{"doi":"10.1002/hbm.25384","title":"Mapping default mode connectivity alterations following a single season of subconcussive impact exposure in youth football","abstract":"Repetitive head impact (RHI) exposure in collision sports may contribute to adverse neurological outcomes in former players. In contrast to a concussion, or mild traumatic brain injury, \"subconcussive\" RHIs represent a more frequent and asymptomatic form of exposure. The neural network-level signatures characterizing subconcussive RHIs in youth collision-sport cohorts such as American Football are not known. Here, we used resting-state functional MRI to examine default mode network (DMN) functional connectivity (FC) following a single football season in youth players (n = 50, ages 8-14) without concussion. Football players demonstrated reduced FC across widespread DMN regions compared with non-collision sport controls at postseason but not preseason. In a subsample from the original cohort (n = 17), players revealed a negative change in FC between preseason and postseason and a positive and compensatory change in FC during the offseason across the majority of DMN regions. Lastly, significant FC changes, including between preseason and postseason and between in- and off-season, were specific to players at the upper end of the head impact frequency distribution. These findings represent initial evidence of network-level FC abnormalities following repetitive, non-concussive RHIs in youth football. Furthermore, the number of subconcussive RHIs proved to be a key factor influencing DMN FC.","journal":"Human Brain Mapping","year":2021,"id":177200,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":20,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9542,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":392013,"name":"Elizabeth M. Davenport","orcid":"0000-0002-8765-6584","position":1,"is_corresponding":false},{"id":471050,"name":"Jillian E. Urban","orcid":"0000-0002-7348-9244","position":2,"is_corresponding":false},{"id":480786,"name":"Yin Xi","orcid":"0000-0001-9743-3010","position":3,"is_corresponding":false},{"id":513597,"name":"James M. Holcomb","orcid":"0000-0001-5551-3936","position":4,"is_corresponding":false},{"id":676550,"name":"Mireille E. Kelley","orcid":"0000-0003-3144-8011","position":5,"is_corresponding":false},{"id":406157,"name":"Christopher T. Whitlow","orcid":"0000-0003-2392-8293","position":6,"is_corresponding":false},{"id":471051,"name":"Alexander K. Powers","orcid":"0000-0003-0125-9762","position":7,"is_corresponding":false},{"id":471052,"name":"Joel D. Stitzel","orcid":"0000-0001-9762-3033","position":8,"is_corresponding":false},{"id":392012,"name":"Joseph A. Maldjian","orcid":"0000-0002-6384-1072","position":9,"is_corresponding":false},{"id":491822,"name":"Jesse C. DeSimone","orcid":"0000-0002-3823-8765","position":0,"is_corresponding":true}],"reference_count":100,"raw_metadata":null,"created_at":"2026-07-18T23:47:28.018172Z","pmid":"33734521","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}