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Previous evidence from neuropsychological and neuroimaging studies suggests functional specialization for tools and related semantic knowledge in a left frontoparietal network. It is still debated whether these areas are involved in the representation of rudimentary movement-relevant knowledge regardless of semantic domains (animate vs. inanimate) or categories (tools vs. nontool objects). Here, we used fMRI to record brain activity while 13 volunteers performed two semantic judgment tasks on visually presented items from three different categories: animals, tools, and nontool objects. Participants had to judge two distinct semantic features: whether two items typically move in a similar way (e.g., a fan and a windmill move in circular motion) or whether they are usually found in the same environment (e.g., a seesaw and a swing are found in a playground). We investigated differences in overall activation (which areas are involved) as well as representational content (which information is encoded) across semantic features and categories. Results of voxel-wise mass univariate analysis showed that, regardless of semantic category, a dissociation emerges between processing information on prototypical location (involving the anterior temporal cortex and the angular gyrus) and movement (linked to left inferior parietal and frontal activation). Multivoxel pattern correlation analyses confirmed the representational segregation of networks encoding task- and category-related aspects of semantic processing. Taken together, these findings suggest that the left frontoparietal network is recruited to process movement properties of items (including both biological and nonbiological motion) regardless of their semantic category.

Background and purpose: Performance validity tests (PVTs) are used in neuropsychological assessments to detect patterns of performance suggesting that the broader evaluation may be an invalid reflection of an individual's abilities. Data on functional motor disorder (FMD) are currently poor and conflicting. We aimed to examine the rate of failure on three different PVTs of nonlitigant, non‐compensation‐seeking FMD patients, and we compared their performance to that of healthy controls and controls asked to simulate malingering (healthy simulators). Methods: We enrolled 29 nonlitigant, non‐compensation‐seeking patients with a clinical diagnosis of FMD, 29 healthy controls, and 29 healthy simulators. Three PVTs, the Coin in the Hand Test (CIH), the Rey 15‐Item Test (REY), and the Finger Tapping Test (FTT), were employed. Results: Functional motor disorder patients showed low rates of failure on the CIH and REY (7% and 10%, respectively) and slightly higher rates on the FTT (15%, n = 26), which implies a motor task. Their performance was statistically comparable to that of healthy controls but statistically different from that of healthy simulators (p < 0.001). Ninety‐three percent of FMD patients, 7% of healthy simulators, and 100% of healthy controls passed at least two of the three tests. Conclusions: Performance validity test performance of nonlitigant, non‐compensation‐seeking patients with FMD ranged from 7% to 15%. Patients' performance was comparable to that of controls and significantly differed from that of simulators. This simple battery of three PVTs could be of practical utility and routinely used in clinical practice. [ABSTRACT FROM AUTHOR]

Background: Pisa syndrome (PS) and camptocormia (CC) are postural abnormalities frequently associated with Parkinson's disease (PD). Their pathophysiology remains unclear, but the role of cognitive deficits has been postulated. Objectives: To identify differences in the neuropsychological functioning of patients with PD with PS or CC compared with matched patients with PD without postural abnormalities. Methods: We performed a case-control study including 57 patients with PD with PS (PS+) or CC (CC+) and 57 PD controls without postural abnormalities matched for sex, age, PD duration, phenotype, and stage. Patients were divided into four groups: PS+ (n = 32), PS+ controls (PS-, n = 32), CC+ (n = 25), and CC+ controls (CC-, n = 25). We compared PS+ versus PS- and CC+ versus CC-using a neuropsychological battery assessing memory, attention, executive functions, visuospatial abilities, and language. Subjective visual vertical (SVV) perception was assessed by the Bucket test as a sign of vestibular function; the misperception of trunk position, defined as a mismatch between the objective versus subjective evaluation of the trunk bending angle >5°, was evaluated in PS+ and CC+. Results: PS+ showed significantly worse visuospatial performances (P = 0.025) and SVV perception (P = 0.038) than their controls, whereas CC+ did not show significant differences compared with their control group. Reduced awareness of postural abnormality was observed in >60% of patients with PS or CC. Conclusions: Low visuospatial performances and vestibular tone imbalance are significantly associated with PS but not with CC. These findings suggest different pathophysiology for the two main postural abnormalities associated with PD and can foster adequate therapeutic and prevention strategies. [ABSTRACT FROM AUTHOR]

Verbal fluency (VF) is an informative cognitive task. Lesion and functional imaging studies implicate distinct cerebral areas that support letter versus semantic fluency and the understanding of neural and cognitive mechanisms underlying task performance. Most lesion studies include chronic stroke patients. People with primary progressive aphasia (PPA) provide complementary evidence for lesion-deficit associations, as different brain areas are affected in stroke versus PPA. In the present study we sought to determine imaging, clinical and demographic correlates of VF in PPA. Thirty-five patients with PPA underwent an assessment with letter and category VF tasks, evaluation of clinical features and an MRI scan for volumetric analysis. We used stepwise regression models to determine which brain areas are associated with VF performance while acknowledging the independent contribution of clinical and demographic factors. Letter fluency was predominantly associated with language severity (R2 = 38%), and correlated with the volume of the left superior temporal regions (R2 = 12%) and the right dorsolateral prefrontal area (R2 = 5%). Semantic fluency was predominantly associated with dementia severity (R2 = 47%) and correlated with the volume of the left inferior temporal gyrus (R2 = 7%). No other variables were significantly associated with performance in the two VF tasks. We concluded that, independently of disease severity, letter fluency is significantly associated with the volume of frontal and temporal areas whereas semantic fluency is associated mainly with the volume of temporal areas. Furthermore, our findings indicated that clinical severity plays a critical role in explaining VF performance in PPA, compared to the other clinical and demographic factors. [ABSTRACT FROM AUTHOR]