Impaired awareness of movement disorders in Parkinson’s disease

Background

This study analyzed the presence of awareness of movement disorders (dyskinesias and hypokinesias) in 25 patients with Parkinson’s disease (PD) and motor fluctuations (dyskinesias, wearing off, on–off fluctuations). Of the few studies that have dealt with this topic, none have analyzed the differences in the awareness of motor deficits by comparing the on and off states using motor scales and an extensive battery of tests to assess cognitive and behavioral functioning.

Methods

PD patients were compared on three different scales that we have devised to measure awareness of movement disorders: Global Awareness of Movement (GAM) Disorders, dyskinesia/hypo-bradykinesia rating scales.

Results

Data showed that PD patients had greater awareness and psychological suffering in the off state than in the on state. In particular, they were troubled by motor disabilities related to hypokinesias and had mood-related symptoms and a perception of disability in activities of daily living. Interestingly, patients only showed a selective reduction of awareness of movement disorders associated with executive functions and related to dyskinesias in the on state, compared to a preserved awareness of hypokinesias in the off state. On the contrary, no association with executive functions was found in the off state.

Conclusion

Our findings suggest that the dopaminergic overstimulation of mesocorticolimbic pathways may cause a dysfunction of prefrontal–subcortical connections related to the impaired insight.     

Development and decay of extra-linguistic communication

Cognitive Pragmatics theory is concerned with analyzing the cognitive processes underlying communication. In previous works we have explained the emergence of communication in context, as revealed by very young children, and the communicative deficits shown by closed head injury patients. The aim of the present work is an extension of Cognitive Pragmatics to the emergence and the decay of extra-linguistic communication. In particular, we investigate the performance of 2- to 7-year-old children and that of Alzheimer's patients in standard and nonstandard (irony and deceit) pragmatic tasks. The predictions derived by Cognitive Pragmatics are confirmed. Comprehension of pragmatic phenomena which are more complex according to the theory emerges later in the development (Experiment 1), and their decay is most severe in Alzheimer's patients (Experiment 2). We conclude that the framework provided by Cognitive Pragmatics can accommodate both the development and the decay of extra-linguistic communication.     

The use of virtual environments for survey spatial ability evaluation in topographical disorientation

Due to their interactivity and to the sense of presence they afford, virtual environments constitute an interesting opportunity to study spatial cognition. In accordance with this perspective, we aimed to introduce a spatial test in virtual simulation in order to investigate the survey spatial ability in patients with topographical disorientation. To do this, we used the "planning in advance task" in a virtual environment that constitutes an effective procedure to experimentally evaluate survey maps. With this procedure we present the single case of a woman, with a right medial temporal lobe lesion, who shows a selective impairment in the acquisition of new spatial relationships. The patient's performance in "planning in advance task" was compared with that of a control group made up of 40 female subjects matched for age and education. Results show how the patient revealed a significantly lower spatial performance when compared to the control group, demonstrating an inability to solve survey-type spatial tasks in complex virtual environments.     

Metaphor comprehension in Alzheimer's disease: novelty matters

The comprehension of non-literal language was investigated in 20 probable Alzheimer's disease (pAD) patients by comparing their performance to that of 20 matched control subjects. pAD patients were unimpaired in the comprehension of conventional metaphors and idioms. However, their performance was significantly lower in the case of non-conventional (novel) metaphor comprehension. This ability was not related to global cognitive deterioration or to deficits in the cognitive domains of attention, memory and language comprehension. On the other hand, the impairment in verbal reasoning appeared to be relevant for both novel and conventional metaphor comprehension. The relationship between novel metaphor comprehension and performance in the visual-spatial planning task of the Behavioral Assessment of the Dysexecutive Syndrome (BADS) suggests that executive impairment, possibly related to prefrontal dysfunction, may be responsible for the pAD patients' poor performance in novel metaphor comprehension. The present findings suggest a role of the prefrontal cortex in novel metaphor comprehension.     

Behavioral and emotional response of Japanese macaque (Macaca fuscata) mothers after their offspring receive an aggression

The authors of this study investigated the behavioral and emotional response of female Japanese macaques (Macaca fuscata) to an aggression received by their offspring to evaluate the existence of cognitive empathic responses in a naturalistic setting. After their offspring received an aggression, mothers did not direct increased affiliative contacts to them. The factors likely to affect the degree of distress in the offspring or the perceived risk for the mother failed to appropriately modulate maternal behavior. Finally, mothers did not increase their frequency of scratching (a behavioral indicator of anxiety) after their offspring had received an aggression. The results suggest Japanese macaque mothers may be unable to understand their offspring's need for distress alleviation after the receipt of aggression.     

Differentiated forgetting rates of spatial knowledge in humans in the absence of repeated testing

Spatial knowledge, necessary for efficient navigation, comprises route knowledge (memory of the landmarks along a route) and survey knowledge (map-like). Available data on the retention in humans of spatial knowledge show that this does not decline systematically over months or years. Here, two groups of participants elaborated route and survey knowledge during navigation in a complex virtual environment before performing route and survey tasks. Both groups were tested 5 minutes after learning and 3 months later, while one group was also tested 1 week and 1 month later (repeated testing). Performance was similar in both groups on the first testing session, remained stable in the repeated tested group, but decreased in the non-repeated tested group, especially on route tasks. These results are the first to reveal a substantial and selective decline of spatial knowledge, occurring only if there is no possibility of reactivating knowledge along repeated testing.     

Single- and Multiple-Group Penalized Factor Analysis: A Trust-Region Algorithm Approach with Integrated Automatic Multiple Tuning Parameter Selection

Psychometrika - Penalized factor analysis is an efficient technique that produces a factor loading matrix with many zero elements thanks to the introduction of sparsity-inducing penalties within...