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BACKGROUND: Motivation deficits and reduced goal-directed behaviour are prominent in schizophrenia (SZ), and significantly contribute to poor functional and treatment outcomes. One of the critical components of the multi-faceted motivation system is effort valuation, which refers to the mental processes involved in computing how much effort one is willing to exert in order to obtain a desired outcome. These effort-cost computations are typically measured using effort-based decision-making (EBDM) paradigms, where individuals must choose between performing low- or high-effort tasks for varying reward magnitudes. Rather than demonstrating an overall unwillingness to expend effort, however, studies have shown that individuals with SZ inefficiently allocate effort across different probability and reward conditions. Thus, in order to better understand the underlying computations involved in effort-based decision-making, the present study sought to model the predictors of choice behaviour in SZ and healthy control (HC) participants. METHODS: Fifty-one SZ patients and 51 demographically-matched HC participants completed the Effort Expenditure for Rewards Task (EEfRT) as a measure of EBDM. In addition, all participants underwent characterization of clinical amotivation severity and cognitive functioning using the Apathy Evaluation Scale (AES) and Brief Assessment of Cognition in Schizophrenia (BACS), respectively. Generalized Estimating Equations (GEE) were subsequently applied to the EEfRT data with a binary logistic distribution used to model the likelihood of choosing hard tasks. A number of models were tested with independent variables including reward magnitude, probability, expected value (EV), diagnostic group, AES, and BACS. RESULTS: GEE models revealed significant main effects for reward magnitude (b = .54, p < .001), probability (b = .02, p < .001), and EV (b = .46, p < .001), but no main effect of group. However, significant interaction terms were found between group and reward (b = -.33, p < .001), group and probability (b = -.01, p = .007), and group and EV (b = -.58, p = .001). While there were no AES or BACS main effects, there were significant AES x reward (b = -.02, p < .001) and AES x EV (b = -.02, p = .01) interactions, as well as BACS x reward (b = .11, p < .001), BACS x probability (b = .01, p < .001), and BACS x EV (b = .31, p < .001) interactions. DISCUSSION: While SZ and HC participants are similarly willing to exert effort in pursuit of a reward, patients with SZ are less likely to utilize important information regarding the magnitude, probability, and expected value associated with that reward in driving their effort-based decision-making. Moreover, reward magnitude and EV are less predictive of effortful choices for individuals with greater motivation and cognitive impairments, regardless of their diagnostic status. Taken together, these findings suggest a direct link between amotivation, cognition, and inefficient utilization of reward and probability information in the context of choice behaviour and effort-cost computations.

Background Although many comprehensive batteries exist to evaluate the nature and degree of cognitive impairments in patients with schizophrenia, short batteries hold promise for rapidly screening and estimating deficits in global cognition. Recently, the Brief Neurocognitive Assessment (BNA) was established and has been shown to have similar validity and utility to a more comprehensive battery of cognitive tests in evaluating global cognitive impairments in patients with schizophrenia. The present study sought to further establish the validity of the BNA by comparing it with the MATRICS Consensus Cognitive Battery (MCCB). Methods One-hundred seventy-six patients with schizophrenia and 300 healthy volunteers participated in the present study. Global cognition was evaluated using the MCCB composite score and estimated using the BNA. To examine practice effects and test–retest reliability, patients were re-assessed after 4 weeks. Results The BNA was highly correlated with global cognition as evaluated by the MCCB in both the schizophrenia ( r = 0.82) and healthy control samples ( r = 0.75). Both instruments were similarly sensitive to deficits in global cognition in patients with schizophrenia relative to healthy controls. The BNA also demonstrated high test–retest reliability in patients with schizophrenia ( r = 0.87), comparable to the level observed with the MCCB ( r = 0.91). In addition, both the BNA and MCCB showed a similar level of practice effects (both Cohen's d = 0.11), and both instruments demonstrated equivalent sensitivities to longitudinal change. Furthermore, scores from the BNA and MCCB were related to symptom severity and functional capacity to a similar degree. Conclusions The BNA provides clinicians and researchers with an efficient and reliable means by which to evaluate global neurocognitive impairments in patients with schizophrenia by allowing estimation of performance on a more comprehensive standardized battery.

Pain is a common problem faced by Parkinson's disease (PD) patients. Despite its impact and disabling effects pain is still frequently overlooked. In this study we analyze a representative sample of peer reviewed literature for the prevalence and types of pain in PD, the impact and significance of pain in the quality of life of the PD patient and the challenges inherent in the diagnosis and management of pain in PD patients. We compared and analyzed the findings of articles indexed in the PubMed database which looked at symptoms reported by large cohorts of PD patients. These articles all reported the incidence, nature and quality of pain in these patients and described the effects of pain on quality of life and generally were cross-sectional, retrospective or case-control studies, though a major pharmacoepidemiological design study was also analyzed. Results of our analysis showed that the pain was prevalent in 59.77% of PD patients. Five different types of pain were reported by PD patients--dystonia, musculoskeletal pain, nerve/nerve root pain, primary/central pain and according to some, akathisia. Patients who reported pain symptoms were also significantly more likely to report associated depression and a decreased quality of life. Many PD patients also reported poor management of pain and lower analgesic use than would be expected. We further discuss some of the possible approaches toward the development of a treatment algorithm regarding the management of pain in PD. We conclude that pain in is an under-recognized and under treated symptom in PD patients. Effective management of pain in PD patients would significantly improve their quality of life. Our analysis is in line with current thinking that identifies PD is much more of a multisystem disease with non-motor symptoms than previously thought.

Aim While much research has been conducted towards understanding the basis of visual hallucinations in Parkinson's disease, little has focused on characterizing the content and patients' emotional experience. These factors are likely very influential on a patient's decision to seek treatment, a critical aspect of any symptom from the clinical perspective. Methods A retrospective chart analysis was performed on Parkinson's disease patients seen in a community-based Parkinson's Disease and Movement Disorder Clinic between 2005 and 2010. Results The study consisted of 334 patients with Parkinson's disease, among whom 10.5% had visual hallucinations. Hoehn and Yahr disease stage (P = 0.001), concurrent presence of dementia (P = 0.001),and sex (P = 0.031) were significant onset predictors. The most significant determinant of treatment-seeking was emotional reaction, namely whether hallucinations were bothersome (P = 0.008). However, the specific type of content during hallucinations was sometimes more influential and contradicted emotional response. Conclusion Although treatment-seeking can be predicted by how individuals feel about hallucinations, a patient's decision may not be logically consistent. We suggest that clinicians offer treatment based on patients' recollections and opinions.

Young onset Parkinson's disease patients, typically aged 21 to between 40 and 55, have symptomatology similar to regular onset patients. Despite this, we suspect that physicians take longer to diagnose young onset patients since Parkinson's disease is ruled out due to the younger age. The history prior to diagnosis of 14 young onset patients (within 21 to 45 years of age) was compared with an equivalent number of regular onset patients matched by gender, tremor presence, and Hoehn and Yahr stage. Indeed, a longer period of time was taken to diagnose younger patients with an average of additional 15 months (p

Background Despite being an important non-motor symptom of PD, pain remains largely understudied in PD patients. Experiencing symptoms of pain is highly disruptive of general functioning, as it may hinder both physical prowess and psychological well-being. Although pain is prevalent in the otherwise healthy geriatric population, its increased presence in PD, and the difficulty it poses when combined with other hallmark motor symptoms necessitates further investigation. An improved understanding of factors that aggravate pain, and methods that alleviate discomfort may provide significant insight on the basis of pain in PD. Such information may ultimately allow healthcare professionals to achieve the goal of improved PD patient management. Objective To study the associations between various factors and pain in a Parkinson's disease (PD) patient population. Methods This study investigated 121 PD patients, of which 80 reported to have pain in at least one area of the body. Exclusion criteria included patients suffering from external causes of pain, such as trauma and patients with cognitive impairment whose accounts may not have been reliable. Further inquiry determined the etiology of pain, as well as aggravating and alleviating factors. The efficacies of pharmacological or non-pharmacological therapies were assessed through additional questioning. Individuals were also asked whether their pain was unintentionally affected by other measures, such as prescribed PD medications. Results Multiple linear regression analysis with a Wald test value of 4.070 (p = 0.044) demonstrated a statistically significant relationship between the administration of analgesics in patients with high reported pain and their pain relief. However, patients who experienced moderate pain did not exhibit any statistically significant levels of pain relief with the use of analgesics (Wald = 2.097, p = 0.148). Similarly, non-pharmacological therapies, PD medicine, and comorbidities showed no statistically significant correlations with pain relief. Conclusions Physicians should be aware of the physiological and psychological factors that form major components of pain relief, and that patient education and support are critical to successful treatment programs.

Among the constellation of symptoms that characterize schizophrenia, negative symptoms have emerged as a critical feature linked to the functional impairment experienced by affected individuals. Despite advances in our understanding of the role of negative symptoms in the illness, effective treatments for these debilitating symptoms have remained elusive. In this review we explore the contemporary conceptualization of negative symptoms in schizophrenia, including the identification of two key subdomains of diminished expression and amotivation, and clarifications around hedonic capacity. We then explore strategies for clinical assessments of negative symptoms, followed by findings using objective paradigms for evaluating discrete aspects of these negative symptoms in clinical populations and animal models, both for symptoms of diminished expression and within the multifaceted motivation system. We conclude with a consideration of current strategies for drug development for these negative symptoms, the role of heterogeneity in the clinical presentation of symptoms in schizophrenia and opportunities for personalized assessment and treatment approaches, as well as a commentary on current clinical drug trial design and the role of environmental opportunities for novel treatments to effect change and improve outcomes for affected individuals.

The Heinrichs-Carpenter Quality of Life Scale (QLS) is the most extensively used real-world community functioning scale in schizophrenia research. However, the extensive time required to administer it and the inclusion of items that overlap conceptually with negative symptoms limit its use across studies. The present study examined the validity and utility of two abbreviated QLS measures against the full QLS excluding negative symptom items.The sample included 1427 patients with schizophrenia who completed the baseline visit in the CATIE study. The validity of two abbreviated QLS measures (7-item and 4-item) were examined with the full QLS, excluding the intrapsychic foundations subscale, using correlation analysis. The utility of the abbreviated measures was explored by examining associations between the functioning scales and clinical variables and longitudinal change.Both abbreviated QLS measures were highly predictive of the full QLS (both r=0.91, p0.001), with no difference in predictive value between the abridged measures. Functional status was significantly associated with symptoms and cognition. Importantly, the strength of these associations was similar between the abbreviated and full QLS. Finally, multiple regression models examining the explanatory power of amotivation/apathy in predicting functioning scores after other symptoms and neurocognition had been accounted for were essentially identical irrespective of the QLS instrument used as the dependent measure. Longitudinal change was also similar across the three scales.The 7-item abbreviated QLS is recommended as a brief measure of community functioning for individuals with schizophrenia, especially when assessment of functional outcome is not the focus.

Action tremor (AT) and resting tremor (RT) have been widely cited in many studies with Parkinson's disease (PD) patients, but studies looking at the association between the two tremor types are few and show inconsistent results. This study will look at the prevalence and association of AT and RT in a large sample of idiopathic PD patients, and will put the results into context with the literature.A retrospective chart review analysis of 332 patients with idiopathic PD was performed. Prevalence rates of particular tremor types were noted. The presence of AT was analyzed relative to the presence and severity of RT.Nearly all individuals with AT also had RT. The concurrence of the two tremor types was found to be highly significant by statistical analysis (P0.0001). The severity of RT, measured by its laterality, may also be of importance, albeit to a much smaller extent if at all. Neither presence of tremor nor type of tremor present was influenced by patient gender, age, or Hoehn and Yahr stage of PD.The results indicate that AT has extensive presence in PD. This and its seemingly close relationship to RT suggest that AT may be considered a variant of RT, particularly in PD patients. The degree of association between RT and AT needs to be further analyzed in PD, as well as in essential tremor (ET) and ET-PD.

Parkinson's disease (PD) is a neurodegenerative illness characterized by various non-motor symptoms that may contribute to disability, impaired quality of life and shortened life expectancy. The aim of present study was to determine the relative prevalence of common non-motor symptoms in various ethnic groups. A retrospective chart analysis was performed on Parkinson's disease patients where a total of 314 PD patients from six ethnic categories were examined for the occurrence of anxiety, visual hallucinations, nocturia, drooling and dementia. Our results show that anxiety in PD patients was correlated with their ethnicity classification. Interesting trends were observed with respect to nocturia and dementia symptoms and no significant differences were found between ethnic groups for visual hallucinations and drooling. Our study shows that non-motor symptoms of Parkinson's disease are prevalent across all ethnic groups, and except anxiety there may not be any impact of ethnicity on dementia, nocturia, drooling, and visual hallucinations.

Many patients with restless legs syndrome (RLS) and Parkinson's disease (PD) report having pain, however, the impact of the combination of PD and RLS on pain has not been analyzed extensively. The objective of this study was to explore the potential relationship between RLS and pain in individuals with and without PD, the prevalence of RLS in PD, the prevalence and severity of pain in PD and RLS, and how these measures are related to PD patients and controls.The study included 127 PD patients and an equal number of non-PD patients who were assessed for pain and RLS-like symptoms by using RLS diagnostic survey, RLS rating scale and Brief Pain Inventory.The results showed that 21.3% of PD patients had RLS, compared to only 4.7% in the control group, representing a highly significant difference (p0.005). The frequency of reporting pain was also significantly higher among PD patients with RLS (p0.005), but not in control group. However, the mean difference in average pain severity was not significantly different between the PD with RLS and non-PD with RLS, nor was the pain level and severity significantly correlated with RLS severity for either group.The presence of pain in PD patients may be exacerbated by RLS or in RLS patients, having PD may exacerbate pain.

Corticobasal degeneration is a progressive neurodegenerative disease involving the cerebral cortex and basal ganglia and leads primarily to motor symptoms and cognitive dysfunction. Unilateral arm dystonia is a common presenting symptom in many patients with corticobasal degeneration. This study attempts to determine if a relationship exists between arm dystonia in corticobasal degeneration and the handedness of the patient. A chart review of 12 right-handed patients (six males and six females) diagnosed with corticobasal degeneration seen in a Parkinson’s disease clinic was conducted. With the exception of a single individual who was afflicted in her dominant arm, all had dystonia in their left arm. The ages of the female patients were substantially lower than their male counterparts. Although the sample size of the patient population is small, the results raise an interesting question: is arm dystonia in corticobasal degeneration more commonly seen on the contralateral side of the dominant hand. Further observation is needed to establish a correlation.