Contrasting cortical inhibitory and facilitatory mechanisms between COPD patients and healthy individuals.

Objective: To compare and contrast the mechanisms of cortical inhibition and facilitation in patients with Chronic Obstructive Pulmonary Disease (COPD) against those in healthy control individuals. Study Design: A cross-sectional study design will be utilized to investigate differences in cortical excitability and plasticity between COPD patients and healthy individuals. Participants: COPD Group: Adults diagnosed with COPD, confirmed by spirometry according to GOLD guidelines. Control Group: Healthy, age-matched adults with no history of respiratory or neurological disorders. Sample Size: A total of 40 participants, 20 in each group, were determined by power analysis to detect significant differences with an alpha of 0.05 and a power of 0.8. Inclusion Criteria: For COPD group: Diagnosed with COPD, stages II to III according to GOLD guidelines. For Control group: No history of respiratory diseases, non-smokers or smokers with less than a 10-pack-year history. Exclusion Criteria: History of neurological disorders or significant cognitive impairment. Use of medications known to affect cortical excitability. Contraindications to transcranial magnetic stimulation (TMS). Methods: Preliminary Assessment: Clinical evaluation and history taking. Spirometry to confirm COPD diagnosis and classify severity. Mini-Mental State Examination (MMSE) to rule out significant cognitive impairment. Cortical Excitability Testing: Transcranial Magnetic Stimulation (TMS): To assess cortical inhibitory and facilitatory mechanisms. Measurements will include: Motor Threshold (MT) Cortical Silent Period (CSP) Intracortical Facilitation (ICF) Short-interval Intracortical Inhibition (SICI) Procedure: Participants will be seated comfortably in an armchair with their heads supported. TMS will be performed using a figure-of-eight coil, systematically moved to find the optimal scalp position (hotspot) for eliciting motor-evoked potentials (MEPs) in the contralateral hand muscles. Resting and active motor thresholds will be determined. CSP, ICF, and SICI will be measured according to standard protocols. Data Analysis: Descriptive statistics will summarize demographic and clinical characteristics. Group differences in MT, CSP, ICF, and SICI will be analyzed using independent t-tests or Mann-Whitney U tests depending on data normality. Correlation analyses will examine the relationship between clinical severity of COPD and measures of cortical excitability. Ethics: This study will be conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Board. Informed consent will be obtained from all participants. Timeline: The study is expected to be completed over 12 months, including recruitment, data collection, analysis, and dissemination of findings. Dissemination: Results will be submitted for publication in a peer-reviewed journal and presented at relevant conferences.