Electroencephalographic Abnormalities in a Patient Suffering from Long-Term Neuropsychological Complications following SARS-CoV-2 Infection.

Introduction: Emotional apathy has recently been identified as a common symptom of long COVID. While recent meta-analyses have demonstrated generalized EEG slowing with the emergence of delta rhythms in patients hospitalized for severe SARS-CoV-2 infection, no EEG study or dopamine transporter scintigraphy (DaTSCAN) has been performed in patients with long COVID presenting with apathy. The objective of this case report was to explore the pathophysiology of neuropsychological symptoms in long COVID. Case Presentation: A 47-year-old patient who developed a long COVID with prominent apathy following an initially clinically mild SARS-CoV-2 infection underwent neuropsychological assessment, cerebral MRI, DaTSCAN, and resting-state high-density EEG 7 months after SARS-CoV-2 infection. The EEG data were compared to those of 21 healthy participants. The patient presented with apathy, cognitive difficulties with dysexecutive syndrome, moderate attentional and verbal episodic memory disturbances, and resolution of premorbid mild gaming disorder, mild mood disturbances, and sleep disturbances. His MRI and DaTSCAN were unremarkable. EEG revealed a complex pattern of oscillatory abnormalities compared to the control group, with a strong increase in whole-scalp delta and beta band activity, as well as a decrease in alpha band activity. Overall, these effects were more prominent in the frontal-central-temporal region. Conclusion: These results suggest widespread changes in EEG oscillatory patterns in a patient with long COVID characterized by neuropsychological complications with prominent apathy. Despite the inherent limitations of a case report, these results suggest dysfunction in the cortical networks involved in motivation and emotion.

Attentional Demand of Motor Speech Encoding: Evidence From Parkinson's Disease.

PURPOSE: While the involvement of attention in utterance planning is well established at the conceptual and lexical levels, the attentional demands of postlexical processes are still debated. This study investigates the involvement of attentional resources on motor speech encoding during utterance production in the context of Parkinson's disease (PD), a population allowing to assess if the attentional demands observed in a dual-task paradigm (the dual-task costs [DTCs]) are explained by postlexical difficulties and not solely by executive impairment. METHOD: Speech production was analyzed in a dual-task paradigm with 30 participants presenting with motor speech disorders due to hypokinetic dysarthria in the context of PD. The dual-task comprised an automatic speech task in which participants recited the days of the week and two nonverbal tasks evaluating processing speed and inhibition. The severity of dysarthria and performance in several executive tests (inhibition, verbal fluency, and cognitive shifting) were used as potential predictors of the DTCs. RESULTS: Individuals with PD exhibited a DTC on the nonverbal tasks and on the speech task when the secondary task was inhibition (the most difficult one). Additionally, the severity of dysarthria and a poorer performance in cognitive shifting predicted a more severe DTC on speech rate. Finally, modulation of the magnitude of the DTCs was observed, depending on the difficulty of the nonverbal secondary task. CONCLUSION: The results suggest that, in PD, postlexical processes require attentional resources and cognitive shifting is related to dual-task performance in speech. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.21265893.

Education level affects dual-task gait after deep brain stimulation in Parkinson's disease.

INTRODUCTION: High cognitive reserve is associated with milder cognitive and motor deficits in Parkinson's disease (PD). We investigated whether educational status (as a proxy for cognitive reserve) could modulate dual-task (DT) related gait changes after subthalamic nucleus deep brain stimulation (STN-DBS) in PD. METHODS: DT-related gait changes were assessed in 34 PD patients (age: 60.5 ±â€¯8.7; % female: 44%), before and one year after STN-DBS. Based on walking speed change after DBS, patients were classified into responders (improvement) and non-responders (deterioration) using automated k-means clustering for four DT (i.e. forward and backward counting; semantic and phonemic fluency). RESULTS: Patients with high education level improved DT gait performance compared to lower educated patients (p = 0.03). Baseline cognitive performance, disease progression and stimulation efficiency were similar between groups (i.e. responders versus non-responders). Logistic regression showed an association between responders and high level of education for verbal fluency (semantic/phonemic fluency, beta = 3.9/3.4, p = 0.03). No significant changes for any gait parameter were found using all-group analyses. CONCLUSION: Education level is associated with DT-related gait changes in PD one year post-DBS. Subgroup analyses should be considered for highly variable gait outcomes after STN-DBS. With regard to the predominance of motor-cognitive DT performance in everyday life, a high CR could be considered as a favourable inclusion criterion for future DBS candidates.

[Trajectory of a patient with deep brain stimulation (DBS)]. / Stimulation cérébrale profonde: trajectoire du patient.

An eligibility assessment for deep brain stimulation is performed in order to select patients who are likely to benefit from it. Parkinson's patients have to stop dopaminergic drugs the day before surgery. During the operation, the patient must remain awake for recording of neuronal activity and for test stimulations to optimize the position of the electrodes. Postoperatively, the stimulation is increased progressively in parallel with a decrease of dopaminergic treatments. After about ten days, the patient can return to home and controls continue as an outpatient. Three months postoperatively, a complete testing of the neurostimulator is performed and at the one year follow-up visit, the effectiveness of the DBS is assessed.

Ipsilateral hyperschematia without spatial neglect after right frontal lesion.

The disorder is described as a size distortion involving the side of space. We report the case of a woman with an ipsilateral hyperschematia without neglect after a right frontal lesion. The patient has exhibited a disproportionate enlargement of the right-hand side of objects and added more left-sided petals to the drawn daisy. This pathologic behavior is independent from spatial neglect and from classic frontal perseverations. Our data support the presence of a spatial component to the perception of object size and a specific sub-component of space distortion.

Velocity control in Parkinson's disease: a quantitative analysis of isochrony in scribbling movements.

An experiment was conducted to contrast the motor performance of three groups (N = 20) of participants: (1) patients with confirmed Parkinson Disease (PD) diagnose; (2) age-matched controls; (3) young adults. The task consisted of scribbling freely for 10 s within circular frames of different sizes. Comparison among groups focused on the relation between the figural elements of the trace (overall size and trace length) and the velocity of the drawing movements. Results were analysed within the framework of previous work on normal individuals showing that instantaneous velocity of drawing movements depends jointly on trace curvature (Two-thirds Power Law) and trace extent (Isochrony principle). The motor behaviour of PD patients exhibited all classical symptoms of the disease (reduced average velocity, reduced fluency, micrographia). At a coarse level of analysis both isochrony and the dependence of velocity on curvature, which are supposed to reflect cortical mechanisms, were spared in PD patients. Instead, significant differences with respects to the control groups emerged from an in-depth analysis of the velocity control suggesting that patients did not scale average velocity as effectively as controls. We factored out velocity control by distinguishing the influence of the broad context in which movement is planned--i.e. the size of the limiting frames--from the influence of the local context--i.e. the linear extent of the unit of motor action being executed. The balance between the two factors was found to be distinctively different in PD patients and controls. This difference is discussed in the light of current theorizing on the role of cortical and sub-cortical mechanisms in the aetiology of PD. We argue that the results are congruent with the notion that cortical mechanisms are responsible for generating a parametric template of the desired movement and the BG specify the actual spatio-temporal parameters through a multiplicative gain factor acting on both size and velocity.

Long-term cognitive profile and incidence of dementia after STN-DBS in Parkinson's disease.

An effect of subthalamic nucleus deep brain stimulation (STN-DBS) on cognition has been suspected but long-term observations are lacking. The aim of this study was to evaluate the long-term cognitive profile and the incidence of dementia in a cohort of Parkinson's disease (PD) patients treated by STN-DBS. 57 consecutive patients were prospectively assessed by the mean of a neuropsychological battery over 3 years after surgery. Dementia (DSM-IV) and UPDRS I to IV were recorded. 24.5% of patients converted to dementia over 3 years (incidence of 89 of 1,000 per year). This group of patients cognitively continuously worsened over 3 years up to fulfilling dementia criteria (PDD). The rest of the cohort remained cognitively stable (PD) over the whole follow-up. Preoperative differences between PDD and PD included older age (69.2 +/- 5.8 years; 62.6 +/- 8 years), presence of hallucinations and poorer executive score (10.1 +/- 5.9; 5.5 +/- 4.4). The incidence of dementia over 3 years after STN-DBS is similar to the one reported in medically treated patients. The PDD presented preoperative risk factors of developing dementia similar to those described in medically treated patients. These observations suggest dementia being secondary to the natural evolution of PD rather than a direct effect of STN-DBS.