Aspects of oral communication in patients with Parkinson's disease submitted to Deep Brain Stimulation

Implications of COVID-19 in Parkinson's disease: the purinergic system in a therapeutic-target perspective to diminish neurodegeneration

The pathophysiology of Parkinson's disease (PD) is marked by degeneration of dopaminergic neurons in the substantia nigra. With advent of COVID-19, which is closely associated with generalized inflammation and multiple organ dysfunctions, the PD patients may develop severe conditions of disease leading to exacerbated degeneration. This condition is caused by the excessive release of pro-inflammatory markers, called cytokine storm, that is capable of triggering neurodegenerative conditions by affecting the blood-brain barrier (BBB). A possible SARS-CoV-2 infection, in serious cases, may compromise the immune system by triggering a hyperstimulation of the neuroimmune response, similar to the pathological processes found in PD. From this perspective, the inflammatory scenario triggers oxidative stress and, consequently, cellular dysfunction in the nervous tissue. The P2X7R seems to be the key mediator of the neuroinflammatory process, as it acts by increasing the concentration of ATP, allowing the influx of Ca2+ and the occurrence of mutations in the α-synuclein protein, causing activation of this receptor. Thus, modulation of the purinergic system may have therapeutic potential on the effects of PD, as well as on the damage caused by inflammation of the BBB, which may be able to mitigate the neurodegeneration caused by diseases. Considering all the processes of neuroinflammation, oxidative stress, and mitochondrial dysfunction that PD propose, we can conclude that the P2X7 antagonist acts in the prevention of viral diseases, and it also controls purinergic receptors formed by multi-target compounds directed to self-amplification circuits and, therefore, may be a viable strategy to obtain the desired disease-modifying effect. Thus, purinergic system receptor modulations have a high therapeutic potential for neurodegenerative diseases such as PD.

Effects of near-monotonous speech of persons with Parkinson's disease on listening effort and intelligibility

The majority of patients with Parkinson's disease (PD) develop hypokinetic dysarthria with a disturbance of prosody. The most important acoustic characteristic of prosodic impairment in PD is a lack of fundamental frequency (F0)-variability. It is well established that a lack of F0-variability can negatively influence the speech intelligibility of neurotypical speakers in background noise. The purpose of this study was to investigate which aspect of processing speech realised by speakers with PD is affected by lack of intonation: intelligibility as measured by a transcription task, scaled intelligibility and/or perceived listening effort when there is no background noise. F0-flattening of Semantically Unpredictable Sentences (SUS) was achieved, while the natural F0-declination was preserved. This kind of F0-flattening affected scaled intelligibility and perceived listening effort, while transcription performance remained unchanged.

Relationship Between Oropharyngeal Geometry and Vocal Parameters in Subjects With Parkinson's Disease

OBJECTIVE

To verify whether the dimensions of different segments of the oropharyngeal cavity have different proportions between Parkinson's disease patients and vocally healthy subjects and investigate whether the measurements of these subjects' oropharyngeal geometry associate with their acoustic measurements of voice.

METHOD

Quantitative, descriptive, cross-sectional, and retrospective study with secondary data, approved by the Human Research Ethics Committee under no. 4.325.029. We used vocal samples and data from the oropharyngeal geometry of 40 subjects - 20 with Parkinson's disease stages I to III and 20 who formed the control group, matched for sex and age. Each group had 10 males and 10 females, mean age of 61 years (±6.0). Formant (F1, F2, and F3) and cepstral measures of the sustained vowel /ε/ were extracted and arranged in the database to determine their values using Praat software. The data were descriptively analyzed, with statistics generated with R software. The proportion of oropharyngeal geometry measurements was arranged by mean values and coefficients of variation. Pearson's linear correlation test was applied to relate voice parameters to oropharyngeal geometry, considering P < 0.05, and linear regression test, to justify F2.

RESULTS

The Parkinson's disease group showed a linear relationship between oral cavity length and F1 in males (P = 0.04) and between glottal area and F2 in females (P = 0.00); linear relationships were established according to age in both groups, and a regression model for F2 was estimated (R2 = 0.61). There was no difference between pathological and healthy voices; there was a difference in the proportional relationship of oropharyngeal geometry between the groups.

CONCLUSION

The proportional relationship of oropharyngeal geometry differs between the Parkinson's disease group and the control group, as well as the relationship between oropharyngeal geometry and formant and cepstral values of voice according to the subjects' sex and age.