{"doi":"10.1177/19417381241257258","title":"Conditioning of Motor Evoked Responses After Anterior Cruciate Ligament Reconstruction: Effects of Stimulus Intensity","abstract":"Background: Operant conditioning of motor evoked torque (MEP TORQUE ) can directly target the corticospinal pathway in patients with anterior cruciate ligament (ACL) reconstruction. However, it remains unclear whether operant conditioning can elicit short-term improvements in corticospinal excitability and whether these improvements are influenced by stimulus intensity. Hypothesis: Quadriceps MEP TORQUE responses can be upconditioned in a single session and will elicit short-term adaptations in corticospinal excitability, with higher stimulus intensities eliciting greater effects. Study Design: Randomized controlled laboratory study. Level of Evidence: Level 2. Methods: Thirty-six participants were assessed during a single session of an operant conditioning protocol. Participants were randomized into 1 of 3 groups for stimulus intensity used during operant conditioning based on the participant’s active motor threshold (AMT: 100%, 120%, and 140%). Quadriceps MEP TORQUE amplitude was evaluated during a block of control transcranial magnetic stimulation trials (CTRL) to establish baseline corticospinal excitability, and 3 blocks of conditioning trials (COND) during which participants trained to upcondition their MEP TORQUE . MEP TORQUE recruitment curves were collected to evaluate the effect of operant conditioning on acute corticospinal adaptations. Results: Participants with ACL reconstruction could upcondition their MEP TORQUE in a single session ( P < 0.01; CTRL, 17.27 ± 1.28; COND, 21.35 ± 1.28 [mean ± standard error [SE] in N·m]), but this ability was not influenced by the stimulus intensity used during training ( P = 0.84). Furthermore, significant improvements in corticospinal excitability were observed ( P = 0.05; PRE, 687.91 ± 50.15; POST, 761.08 ± 50.15 [mean ± SE in N·m %AMT]), but stimulus intensity did not influence corticospinal adaptations ( P = 0.67). Conclusion: Operant conditioning can elicit short-term neural adaptations in ACL-reconstructed patients. Future operant conditioning paradigms may effectively use any of the 3 stimulus intensities studied herein. Clinical Relevance: Operant conditioning may be a feasible approach to improve corticospinal excitability after ACL reconstruction.","journal":"Sports Health A Multidisciplinary Approach","year":2024,"id":468259,"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":3,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9625,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2024-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1301430,"name":"Jungsun Moon","orcid":null,"position":1,"is_corresponding":false},{"id":302958,"name":"Chandramouli Krishnan","orcid":"0000-0002-7278-7389","position":2,"is_corresponding":false},{"id":302957,"name":"Riann M. Palmieri‐Smith","orcid":"0000-0001-6790-3691","position":3,"is_corresponding":false},{"id":302956,"name":"Kazandra M. Rodriguez","orcid":"0000-0002-4947-8510","position":0,"is_corresponding":true}],"reference_count":43,"raw_metadata":null,"created_at":"2026-07-19T02:05:19.071498Z","pmid":"38864306","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":[]}