Speech impairment is reported among 70% of the Parkinson’s disease (PD) population, deeply impacting individual quality of life and social costs. Because of the lack of efficacy of pharmacological and DBS treatments, we developed an experimental protocol based on the Lee Silverman Voice Therapy (LSVT) and transcranial direct current stimulation (tDCS) to study the role that such treatments have on electroencephalographic (EEG) oscillations. We enrolled 10 PD patients affected by speech disorders who underwent the 1-month LSVT protocol coupled with tDCS over the right Superior Temporal Gyrus (rSTG). Before and after such therapy, we performed a clinical evaluation through clinical scales and collected the EEG during an overt reading task and a resting state. We report an improvement for the UPDRS-III, the Robertson Dysarthria Profile, the Voice Handicap Index, and the Parkinson's Disease Questionnaire (PDQ-39) for all the patients completing the LSVT. In addition, the PDQ-39 returned a specific improvement for those who received the tDCS (N=6) compared to the sham condition. EEG results highlight a significant alpha and beta de-synchronization during the reading task compared to a resting state as neural signatures of motor and cognitive processing. Strikingly, we found a selective de-synchronization of the high beta band ([15, 30] Hz) after completing the LSVT, specifically related to the reading task and the tDCS condition. It will be crucial to enlarge the current dataset to understand the role of cortical beta oscillations as a key mechanism involved in sensorimotor integration functions during speech processing for the Parkinson's population.