De novo nose-pinching stereotypy with somnolence: Clues to autoimmune encephalitis.

Autoimmune encephalitis (AE) is being increasingly recognized as a cause of new-onset movement disorders. Movement disorders in AE are diverse and range from hyperkinetic conditions such as oromandibular dyskinesias, tremors and chorea to hypokinetic ones such as bradykinesia and parkinsonism. Stereotypies have been described in association with anti-NMDAR encephalitis. Similarly, sleep dysfunction is an underrecognized feature in many AE subtypes, prominently anti-IgLON5 although the correlation of phenotype of sleep dysfunction with a particular antibody subtype in AE is unclear. Despite the recognition of both these features as part of an overreaching spectrum in any patient with AE, seldom are they the sole presenting manifestations. Additionally, the challenge is further compounded in a patient who has seronegative AE since neither sleep disturbances nor stereotypies have been well characterized with this condition yet, and the diagnosis is conditional to exhausting a list of ancillary supportive features. In this brief communication, we describe the case of a young man who presented with hypersomnolence and an unusual focal nose-pinching stereotypy of subacute onset who lacked the presence of other typical clinical characteristics such as cognitive/memory impairment and seizures and had negative autoimmune antibodies but responded to immune therapy dramatically. We propose that the presence of de novo hypersomnolence and stereotypy should inform a potential diagnosis of AE.

Anomalous Putamen Volume in Children With Complex Motor Stereotypies.

BACKGROUND: Complex motor stereotypies in children are repetitive rhythmic movements that have a predictable pattern and location, seem purposeful, but serve no obvious function, tend to be prolonged, and stop with distraction, e.g., arm or hand flapping, waving. They occur in both "primary" (otherwise typically developing) and secondary conditions. These movements are best defined as habitual behaviors and therefore pathophysiologically hypothesized to reside in premotor to posterior putamen circuits. This study sought to clarify the underlying neurobiologic abnormality in children with primary complex motor stereotypies using structural neuroimaging, emphasizing brain regions hypothesized to underlie these atypical behaviors. METHODS: High-resolution anatomic magnetic resonance images, acquired at 3.0 T, were analyzed in children aged eight to twelve years (20 with primary complex motor stereotypies and 20 typically developing). Frontal lobe subregions and striatal structures were delineated for analysis. RESULTS: Significant reductions (P = 0.045) in the stereotypies group were identified in total putamen volume but not in caudate, nucleus accumbens, or frontal subregions. There were no group differences in total cerebral volume. CONCLUSIONS: Findings of a smaller putamen provide preliminary evidence suggesting the potential involvement of the habitual pathway as the underlying anatomic site in primary complex motor stereotypies.

Mirror apraxia affects the peripersonal mirror space. A combined lesion and cerebral activation study.

Mirror apraxia is a condition in which patients with lesions of the posterior parietal cortex have deficits in reaching to objects presented through a mirror. The aim of the present study was to investigate possible mechanisms underlying this disorder. First, we addressed the question of whether mirror apraxia is exhibited to the same extent in peripersonal and in body space. Four patients with lesions of the posterior parietal lobe on either side and with marked mirror apraxia were required to reach for objects that were presented to them through a mirror and located either in body space (i.e. on the body surface) or in peripersonal space (i.e. in the reaching distance). Whereas reaching for objects located in body space was flawless in all patients, the performance deteriorated when the same objects were transferred to the peripersonal space. Although the objects were located only a few centimetres above the body surface, the patients reached towards the virtual object in the mirror. Based on these results we suggest that mirror apraxia may originate from a dissociation between the representations of body schema and peripersonal space and that objects located on the body surface become integrated into the body schema. In the second part of the study, using positron emission tomography study (PET), we studied the cerebral activation pattern during reaching to objects presented through a mirror in the peripersonal space in healthy subjects. The results show that increased neural activity in the anterior part of the intraparietal sulcus and in the dorsal premotor cortex was bound to the transformation of the target position from the mirror space to the real space. In contrast, the activity related to object localization in the mirror occurred at the parieto-occipital junction. Both mirror and arm transformation involved the medial posterior part of the superior parietal lobule, putatively area V6a. The results demonstrate that acting through a mirror is processed in a number of cortical areas of the dorsal stream.

[Stereotypes, developmental disorders and neuroimaging studies]. / Estereotipias, trastornos del desarrollo y estudios con neuroimagen.

INTRODUCTION: We believe that it is of great interest, in neuropediatric clinic, to value the molar behavior disorders and to accomplish the corresponding molecular alterations in the central nervous system. PATIENTS AND METHODS: We studied 26 patients diagnosed of serious disorders of the development, that were presenting a typical clinic with manual stereotypes. We choose at random 5 children to practice them a study of metabolic neuroimaging through the Positron Emission Tomography with 18Fluoro-Deoxi-Glucose (PET-FDG). RESULTS AND CONCLUSIONS: The conclusion, more meaningful, is that the children with serious disorders of the development present a mature failure in the neuro-function circuits of the thalamus, as well as the cortical connection and association areas. This clinical situation is reinforced by the results of the PET-FDG, that presents a characteristic metabolic image of the autism children, with a bilateral decrease of the capitation of FDG, mainly in regions as thalamus, frontal and temporary lobes.