Speech impairment in Parkinson's disease is improved by transcranial application of electromagnetic fields

Monoamine reuptake inhibitors in Parkinson's disease

The motor manifestations of Parkinson's disease (PD) are secondary to a dopamine deficiency in the striatum. However, the degenerative process in PD is not limited to the dopaminergic system and also affects serotonergic and noradrenergic neurons. Because they can increase monoamine levels throughout the brain, monoamine reuptake inhibitors (MAUIs) represent potential therapeutic agents in PD. However, they are seldom used in clinical practice other than as antidepressants and wake-promoting agents. This review article summarises all of the available literature on use of 50 MAUIs in PD. The compounds are divided according to their relative potency for each of the monoamine transporters. Despite wide discrepancy in the methodology of the studies reviewed, the following conclusions can be drawn: (1) selective serotonin transporter (SERT), selective noradrenaline transporter (NET), and dual SERT/NET inhibitors are effective against PD depression; (2) selective dopamine transporter (DAT) and dual DAT/NET inhibitors exert an anti-Parkinsonian effect when administered as monotherapy but do not enhance the anti-Parkinsonian actions of L-3,4-dihydroxyphenylalanine (L-DOPA); (3) dual DAT/SERT inhibitors might enhance the anti-Parkinsonian actions of L-DOPA without worsening dyskinesia; (4) triple DAT/NET/SERT inhibitors might exert an anti-Parkinsonian action as monotherapy and might enhance the anti-Parkinsonian effects of L-DOPA, though at the expense of worsening dyskinesia.

Effects of neurosurgical management of Parkinson's disease on speech characteristics and oromotor function

The present study examined the effects of neurosurgical management of Parkinson's disease (PD), including the procedures of pallidotomy, thalamotomy, and deep-brain stimulation (DBS) on perceptual speech characteristics, speech intelligibility, and oromotor function in a group of 22 participants with PD. The surgical participant group was compared with a group of 25 non-neurologically impaired individuals matched for age and sex. In addition, the study investigated 16 participants with PD who did not undergo neurosurgical management to control for disease progression. Results revealed that neurosurgical intervention did not significantly change the surgical participants' perceptual speech dimensions or oromotor function despite significant postoperative improvements in ratings of general motor function and disease severity. Reasons why neurosurgical intervention resulted in dissimilar outcomes with respect to participants' perceptual speech dimensions and general motor function are proposed.

Treatments for dysarthria in Parkinson's disease

Dysarthria in Parkinson's disease can be characterised by monotony of pitch and loudness, reduced stress, variable rate, imprecise consonants, and a breathy and harsh voice. Use of levodopa to replenish dopamine concentrations in the striatum seems to improve articulation, voice quality, and pitch variation, although some studies show no change in phonatory parameters. Traditional speech therapy can lead to improvement of dysarthria, and intensive programmes have had substantial beneficial effects on vocal loudness. Unilateral surgical lesions of subcortical structures are variably effective for the alleviation of dysarthria, whereas bilateral procedures typically lead to worsening of speech production. Among deep-brain stimulation procedures, only stimulation of the subthalamic nucleus improves some motor components of speech although intelligibility seems to decrease after surgery. Due to the variable treatment effects on parkinsonian speech, management of dysarthria is still challenging for the clinician and should be discussed with the patient.

Effects of speech therapy and pharmacologic and surgical treatments on voice and speech in Parkinson's disease: a review of the literature

The purpose of this review was to examine the different treatment approaches for persons with Parkinson's Disease (PD) and to examine the effects of these treatments on speech. Treatment methods reviewed include speech therapy, pharmacological, and surgical. Research from the 1950s through the 1970s had not demonstrated significant improvements following speech therapy. Recent research has shown that speech therapy (when persons with PD are optimally medicated) has proven to be the most efficacious therapeutic method for improving voice and speech function. Pharmacological methods of treatment in isolation do not appear to significantly improve voice and speech function in PD across research studies. Surgical treatment methods including pallidotomy and deep brain stimulation may be significant treatment options which improve voice and speech function in some persons with PD. Possible explanations for the differential responses to treatment are discussed. Future studies should investigate the effects of combined treatment approaches. Perhaps the combination of pharmacological, surgical and speech treatment will prove superior to treatments combining pharmacological and surgical or pharmacological and speech therapy in improving the communication abilities of persons with PD.