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Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is an autoimmune encephalitis mainly affecting young women. We report a case of a mild paraneoplastic anti-NMDAR encephalitis in a 31-year-old female with an ovarian immature teratoma. The patient exhibited a severe short-term episodic memory impairment and psychiatric symptoms. A detailed diagnostic work-up including complete clinical and laboratory examinations, neuropsychological assessments, and neuroradiological investigations has been done at the onset and during follow-up. The amnestic syndrome and MRI medial-temporal abnormalities reversed after medical and surgical treatment. The present report indicates that the disease can be rapidly reversible if promptly diagnosed and treated. While the disease has already been described elsewhere, the course of neurospychological deficits in adults is not as much known. Usually, when the diagnosis of anti-NMDAR encephalitis is made, the severity of the disease makes the assessment of the neuropsycological profile particulary challenging. The present report is of interest because it describes the complete neuropsychological profile of a mild form of anti-NMDAR encephalitis. [ABSTRACT FROM AUTHOR]

Motor behaviour is controlled by a large set of interacting neural structures, subserving the different components involved in hierarchical motor processes. Few studies have investigated the neural substrate of higher-order motor ideation, i.e. the mental operation of conceiving a movement. The aim of this functional magnetic resonance imaging study was to segregate the neural structures involved in motor ideation from those involved in movement choice and execution. An index finger movement paradigm was adopted, including three different conditions: performing a pre-specified movement, choosing and executing a movement and ideating a movement of choice. The tasks involved either the right or left hand, in separate runs. Neuroimaging results were obtained by comparing the different experimental conditions and computing conjunction maps of the right and left hands for each contrast. Pre-specified movement execution was supported by bilateral fronto-parietal motor regions, the cerebellum and putamen. Choosing and executing finger movement involved mainly left fronto-temporal areas and the anterior cingulate. Motor ideation activated almost exclusively left hemisphere regions, including the inferior, middle and superior frontal regions, middle temporal and middle occipital gyri. These findings show that motor ideation is controlled by a cortical network mainly involved in abstract thinking, cognitive and motor control, semantic and visual imagery processes. [ABSTRACT FROM AUTHOR]

This paper describes some novel spatial tasks and questionnaires designed to assess spatial and orientation abilities. The new tasks and questionnaires were administered to a sample of 90 older adults (41 males, age range 57-90), along with some other tests of spatial ability (Minnesota Paper Form Board, Mental Rotations Test, and Embedded Figures Test) and tests of visuospatial working memory (Corsi's Block Test and Visual Pattern Test). The internal reliability of the new tasks and questionnaires was analyzed, as well as their relationship with the spatial and working memory tests. The results showed that the new spatial tasks are reliable, correlate with working memory and spatial ability tests and, compared with the latters, show stronger correlations with the self-report questionnaires referring to orientation abilities. A model was also tested (with reference to Allen et al. in Intelligence 22:327-355, ) in which the new tasks were assumed to relate to spatial ability and predict orientation abilities as assessed by the self-report measures. [ABSTRACT FROM AUTHOR]

Mental image generation is a complex process mediated by dynamically interrelated components, e.g. image generation and image enrichment of details. This study investigated the cognitive and neural correlates of sequential image generation. An event-related fMRI experiment was carried out in which general and specific images had to be generated sequentially in two different positions. Participants had to generate either a general image first and then a specific one or a specific image first and then a general one, in response to the same word-stimulus. Generation times showed that specific images took shorter to be produced if they had been preceded by the generation of a general image. The fMRI results showed that position of generation and type of image was associated with different patterns of neurofunctional change. When an image was generated as first, areas of activation were found in the parahippocampal, fusiform and occipital regions. These are areas associated with memory retrieval and visual processing. When an image was generated as second, significant activations were found in superior temporal and precuneus areas, brain structures that are involved in the storage of visual memory for object shapes and imagery, respectively. The generation of a general image was supported by frontal areas and by the precuneus. The generation of a specific image involved frontal and thalamic areas (structures associated with visual processing of details) and the posterior cingulate cortex. When shifting from a specific image to a general one, a higher level of activity was found in the middle frontal gyrus involved in global visuo-spatial processing, suggesting that the generation of specific images required the retrieval of an object’s global shape. Altogether, these data suggest that the sequential generation of different types of image is associated with discrete processes but also shares common cognitive and neural components. [ABSTRACT FROM AUTHOR]