Efficacy of LSVT-LOUD Therapy on Voice, Speech, and Quality of Life in Parkinson's Disease

Inclusion Criteria: Diagnosis: Patients with a confirmed diagnosis of Idiopathic Parkinson's Disease (Hoehn and Yahr stages I-III). Age: Individuals aged 40-80 years. Language: Native Turkish speakers. Cognitive Status: Sufficient cognitive function to participate in therapy (e.g., Mini-Mental State Examination (MMSE) score ≥ 24). Communication: Presence of voice or speech impairment (e.g., hypophonia, reduced intelligibility) as confirmed by a speech-language pathologist. Stability: Stable medication regimen for at least 1 month prior to the study initiation. Exclusion Criteria: Neurological Comorbidities: Presence of other significant neurological disorders (e.g., stroke, traumatic brain injury, multiple sclerosis) or active voice disorders (e.g., vocal cord nodules, laryngeal cancer). Hearing Impairment: Uncorrected hearing loss that would interfere with speech assessment or therapy. Cognitive Impairment: Diagnosis of dementia or severe cognitive impairment that prevents participation in the intensive LSVT-LOUD protocol. Recent Surgery: History of laryngeal surgery or deep brain stimulation (DBS) within the last 6 months. Therapy History: Previous experience with LSVT-LOUD or intensive speech therapy within the past year.