Central Pain in Parkinson's Disease: Behavioral and Cognitive Characteristics.

INTRODUCTION: Pain is a major nonmotor symptom of Parkinson's disease (PD), and central parkinsonian pain is the core feature of the putative Park pain subtype of PD. This study aimed to explore the cognitive and behavioral profile of PD patients with central parkinsonian pain. Material and Methods. A structured interview was used to identify and characterize pain in a cohort of 260 consecutive PD patients. The Ford classification of pain was applied. The Dementia Rating Scale-2 (DRS-2) and the Impulse Control Disorders in Parkinson's Disease Short Form (QUIP-S) were administered, and patients' smoking habits were recorded. The Unified Parkinson's Disease Rating Scale (UPDRS) was used to assess motor and nonmotor symptoms in off and on conditions. RESULTS: One hundred and eighty-eight patients (68%) reported pain; and in 41 (22%) of them, the pain was classified as central parkinsonian pain. PD patients with central parkinsonian pain had better cognitive performance in DRS-2 Initiation/Perseveration and Conceptualization subscales but reported more other compulsive behaviors (e.g., hobbyism, punding, and walkabout) and had more current smoking habits than those without pain or with non-central parkinsonian pain. Multiple logistic regression analyses revealed that the DRS-2 Conceptualization subscale, other compulsive behaviors, and smoking habits remained statistically associated with central parkinsonian pain even when other significant covariates were considered. Only patients with pain, regardless of type, had a gambling disorder. Discussion. The study results provide further evidence that pain revealed that patients with central parkinsonian pain are more likely to present compulsive or addictive behaviors, despite having more preserved cognitive performance. Patients with central parkinsonian pain appear to have a distinct phenotype of PD.

Prognostic value of odor identification impairment in multiple sclerosis: 10-Years follow-up.

BACKGROUND: Olfactory dysfunction has been linked to clinical severity variables in multiple MS populations. Though, its prognostic value is still unknown. OBJECTIVE: The aim of this study was to explore the long-term outcome associated with Brief-Smell Identification Test (B-SIT) performance in a cohort of MS patients. METHODS: A retrospective review of the clinical records was conducted in 149 patients who participated in a previous study, with a median follow-up of 121 months. Demographic and clinical data regarding the last clinical appointment with EDSS measurement were collected. Multiple Sclerosis Severity Scale (MSSS) and Age-Related Multiple Sclerosis Severity (ARMSS) scores were calculated. Date of the last clinical contact or death was recorded. RESULTS: Among MS patients with progressive clinical course (n = 33), those with impaired B-SIT at baseline had greater change per month during follow-up (as measured by increases in MSSS and ARMSS scores) and a higher hazard of death. No significant associations were found among patients with relapsing and remitting MS (n = 116). CONCLUSIONS: The study results demonstrate that odor identification impairment has prognostic value in progressive MS, suggesting that a brief odor identification measure can be a marker of neurodegeneration in progressive MS.

Acquired hepatocerebral degeneration and hepatic encephalopathy: one or two entities?

BACKGROUND AND PURPOSE: Acquired hepatocerebral degeneration (AHD) and hepatic encephalopathy (HE) are neurological complications of chronic liver disease (CLD) with portosystemic shunt. While HE is common, AHD is a rare entity, and the clinical imaging relationships observed in small series lack validation in large patient cohorts. The aim of this study was to characterize a cohort of AHD patients and to explore possible associations with HE coexistence. METHODS: We performed a retrospective analysis of patients with a working AHD diagnosis, between 2008 and 2019. Clinical, laboratory, imaging and neuropsychological results at first neurological observation were reviewed and compared between the 'AHD' group and the 'AHD with HE' group. RESULTS: A total of 76 patients were recruited. The most frequent neurological manifestations were neuropsychiatric (93.4%) and extrapyramidal (84.2%). Only 38% of patients had hypermanganesemia. Compared with the AHD group, the AHD with HE group had more hyperkinetic movement disorders (71.4% vs. 38.5%; P = 0.05), a higher number of patients on the dementia spectrum (57.7% vs. 20%; P = 0.04), higher median ammonia levels (P = 0.014) and more widespread cortico-subcortical and pyramidal involvement on brain magnetic resonance imaging. Nineteen patients underwent liver transplantation, with significantly improved survival (P = 0.006). DISCUSSION: Hepatic encephalopathy and AHD often coexist in the same patient. Seventy-six patients with CLD and AHD were evaluated, making this one of the largest reported AHD cohorts. Blood manganese level was a weak diagnostic marker in AHD. Early liver function restoration through liver transplantation improved survival. Our report provides a detailed description of the phenotype and long-term outcome of AHD, with relevance for diagnosis and treatment.

Sleep disturbances in Parkinson's disease are associated with central parkinsonian pain.

INTRODUCTION: Sleep disturbances and pain are common non-motor symptoms in Parkinson's disease (PD). This study aimed to explore the association between these two symptoms in a cohort of patients with PD. MATERIALS AND METHODS: The Parkinson's Disease Sleep Scale (PDSS-2) was used to identify sleep disturbances in a series of 229 PD patients. The identification and characterization of pain was performed by a semi-structured interview and by the application of the Ford classification and the Brief Pain Inventory (BPI). The Unified Parkinson's Disease Rating Scale-III, Hoehn & Yahr (H&Y), and Schwab and England Independence Scale were used to assess motor symptoms and functional independence in off and on conditions. The Hospital Anxiety and Depression Scale (HADS) and SF-36 were applied to screen for anxiety and depression and to evaluate the quality of life. Non-parametric tests were used for group comparisons and logistic regressions were applied to explore predictors of sleep disturbances. RESULTS: Seventy-five (33%) patients had clinically relevant sleep disturbances (PDSS-2≥18) and 162 patients (71%) reported pain. Of those with pain, 38 (24%) had central parkinsonian pain. PD patients with sleep disturbances experienced more pain and had more severe motor symptoms, lower functional independence, more anxiety and depression symptoms, and worst quality of life. Among patients with pain, central parkinsonian pain was the subtype of pain with the highest odds of sleep disturbances, even when taking into account motor symptoms (H&Y off), motor fluctuations, intensity of pain (BPI), and symptoms of anxiety and depression (HADS). CONCLUSIONS: The association between pain and sleep disturbances in PD appears to be dependent on subtype of pain. The close relationship between central parkinsonian pain and sleep disturbances in PD raises the possibility of common pathophysiological mechanisms. A better understanding of the relationship between sleep disturbances and central parkinsonian pain may contribute to the development of new care strategies in PD patients.

Amnesia and driving.

Two experienced drivers who developed severe amnesia due to bilateral hippocampal lesions participated in a series of standardized challenges of driving performance and knowledge of driving rules. During drives in a high fidelity simulator and on the road in an instrumented vehicle, they demonstrated vehicle control similar to that of normal drivers on measures of steering, speed control, safety errors, and driving with distraction. Their knowledge of driving rules, safety procedures, and road sign meaning also was normal. However, both participants were impaired at following route directions, and both had unsafe responses in a difficult crash avoidance scenario on the simulator. These findings suggest that memory impairment acquired by experienced drivers does not impair most aspects of driving performance, but may increase safety risk under some challenging circumstances.

Non-declarative memory in the rehabilitation of amnesia.

The ability of amnesic patients to learn and retain non-declarative information has been consistently demonstrated in the literature. This knowledge provided by basic cognitive neuroscience studies has been widely neglected in neuropsychological rehabilitation of memory impaired patients. This study reports the case of a 43 year old man with severe amnesia following an anterior communicating artery (ACoA) aneurysm rupture. The patient integrated a comprehensive (holistic) day treatment programme for rehabilitation of brain injury. The programme explored the advantages of using preserved non-declarative memory capacities, in the context of commonly used rehabilitation approaches (i.e. compensation for lost function and domain-specific learning). The patient's ability to learn and retain new cognitive and perceptual-motor skills was found to be critical for the patient's improved independence and successful return to work.

A biologically plausible acoustic motion detection neural network.

In this paper we present an acoustic motion detection system to be used in a small mobile robot. While the first purpose of the system has been to be a reliable computational implementation, cheap enough to be built in hardware, effort has also been taken to construct a biologically plausible solution. The motion detector consists of a neural network composed of motion-direction sensitive neurons with a preferred direction and a preferred region of the azimuth. The system was designed to produce a higher response when stimulated by motion in the preferred direction than in the null direction and that is in fact what the system does, which means that, as desired, the system can detect motion and distinguish its direction.