Anti-leucine-rich glioma-inactivated 1 encephalitis revealed by a manic episode: insights from frontal lobe dysfunction in neuropsychiatry through neuropsychology and metabolic imaging. A case report.

Background: Anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis is a limbic encephalitis that rarely presents as an isolated psychiatric syndrome. Case presentation: A 70-year-old patient first presented with behavioral disorder including hyperactivity, euphoria, with disinhibition and accelerated speech associated with severe insomnia and cognitive disorder. A manic episode was diagnosed and he received various psychotropic medications with no improvement. Invesitgations were negative (MRI showed T2 aspecific hyperintensities with no hyperintensities in limbic regions and EEG was normal). He was transferred to a nursing home, with a diagnosis of neurodegenerative condition. Later, he was referred to our unit for further investigations. A cerebral 18F-FDG-PET revealed an association of frontal hypometabolism and temporal and striatum hypermetabolism and CSF analysis revealed slightly increased white blood cell counts. Plasmatic anti-LGI1 antibodies were detected. The patient was treated with intra-venous immunoglobulin (IvIg) but showed no improvement. Second-line treatment (a combination of rituximab and cyclophosmphamide) was then administered for a year, leading to an improvement of neuropsychiatric symptoms and normalization of metabolic impairment on 18F-FDG-PET. Conclusion: In this report, we describe a novel case of a patient withanti-LGI1 encephalitis with a predominant long-term psychiatric presentation. An atypical presentation (such as atypical psychiatric symptoms, neurocognitive disorder, and hyponatremia) should prompt further investigations such as CSF analysis, considering that MRI and EEG may be normal. FDG-PET might be of interest but few data are available in the literature. Early treatment of anti-LGI1 encephalitis is crucial for overall prognosis and may delay the development of dementia in some cases.

Evaluation of the cognitive outcome after out-of-hospital cardiac arrest: The role of thalamus.

Cardiac arrest survivors develop a variety of neuropsychological impairments and neuroanatomical lesions. The goal of this study is to evaluate if brain voxel-based morphometry and lesional Magnetic Resonance Imaging (MRI) analyses performed in the acute phase of an Out-of-Hospital Cardiac Arrest (OHCA) can be sensitive enough to predict the persistence of neuropsychological disorders beyond 3 months. Survivors underwent a prospective brain MRI during the first month after an OHCA and performed neuropsychological assessments at 1 and 3 months. According to the second neuropsychological assessment, survivors were separated into two subgroups, a deficit subgroup with persistent memory, executive functions, attention and/or praxis disorders (n = 11) and a preserved subgroup, disorders free (n = 14). Brain vascular lesion images were investigated, and volumetric changes were compared with healthy controls. Correlations were discussed between brain MRI results, OHCA data and the second neuropsychological assessment. Analyses of acute ischemic lesions did not reveal significant differences between the two subgroups (p = .35), and correlations with cognitive impairments could not be assessed. voxel-based morphometry analyses revealed a global cerebral volume reduction for the two subgroups and a clear decrease of the right thalamic volume for the deficit subgroup. It was associated with a cognitive dysexecutive syndrome represented by four executive indexes according to the 'Groupe de Réflexion pour l'Evaluation des Fonctions EXécutives' criteria. The right thalamus atrophy seems to be more predictive than the vascular lesions and more specific than a global cerebral volume reduction of post-OHCA neuropsychological executive disorders.

Retrograde amnesia with transposition in the past: A neuropsychological and PET study of a case.

OBJECTIVE: Retrograde amnesia (RA) with a "transposition in the past" phenomenon has been rarely reported. Patients presenting disproportionate RA for all events over a defined period of time offer an opportunity to investigate the unclear relationship between autobiographical memory and the self, through the well-known self-memory system (SMS). METHOD: We report the case of a 31-year-old right-handed woman who presented to the emergency department of our tertiary care center with an ongoing episode of RA. After resolution of the episode, she had a second transient episode of RA. An extensive neuropsychological battery was performed to assess her autobiographical and nonautobiographical memory during and after the 2 episodes of RA. She also had an 18F-Fluorodeoxyglucose Positron Emission Tomography (FDG PET) scan during the second RA episode. RESULTS: During the 2 RA episodes, results showed lacunar amnesia for autobiographical as well as nonautobiographical memories of the time period between the present and the past 15 years, with preserved anterograde memory. Moreover, her memories before this lost period were more accurate than those after the 2 RA episodes. During the 2 RA episodes, our patient experienced a "transposition in the past" phenomenon. Statistical analysis of the PET scan demonstrated a significant hypometabolism within the right hippocampus. CONCLUSION: The "transposition in the past" phenomenon illustrates the relationship between both episodic and autobiographical memories and the functioning of self, according to the SMS model. Moreover, this case suggests the involvement of the hippocampus in this phenomenon. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Mirrored and rotated stimuli are not the same: A neuropsychological and lesion mapping study.

Agnosia for mirrored stimuli is a rare clinical deficit. Only eight patients have been reported in the literature so far and little is known about the neural substrates of this agnosia. Using a previously developed experimental test designed to assess this agnosia, namely the Mirror and Orientation Agnosia Test (MOAT), as well as voxel-lesion symptom mapping (VLSM), we tested the hypothesis that focal brain-injured patients with right parietal damage would be impaired in the discrimination between the canonical view of a visual object and its mirrored and rotated images. Thirty-four consecutively recruited patients with a stroke involving the right or left parietal lobe have been included: twenty patients (59%) had a deficit on at least one of the six conditions of the MOAT, fourteen patients (41%) had a deficit on the mirror condition, twelve patients (35%) had a deficit on at least one the four rotated conditions and one had a truly selective agnosia for mirrored stimuli. A lesion analysis showed that discrimination of mirrored stimuli was correlated to the mesial part of the posterior superior temporal gyrus and the lateral part of the inferior parietal lobule, while discrimination of rotated stimuli was correlated to the lateral part of the posterior superior temporal gyrus and the mesial part of the inferior parietal lobule, with only a small overlap between the two. These data suggest that the right visual 'dorsal' pathway is essential for accurate perception of mirrored and rotated stimuli, with a selective cognitive process and anatomical network underlying our ability to discriminate between mirrored images, different from the process of discriminating between rotated images.

Agnosia for mirror stimuli: a new case report with a small parietal lesion.

Only seven cases of agnosia for mirror stimuli have been reported, always with an extensive lesion. We report a new case of an agnosia for mirror stimuli due to a circumscribed lesion. An extensive battery of neuropsychological tests and a new experimental procedure to assess visual object mirror and orientation discrimination were assessed 10 days after the onset of clinical symptoms, and 5 years later. The performances of our patient were compared with those of four healthy control subjects matched for age. This test revealed an agnosia for mirror stimuli. Brain imaging showed a small right occipitoparietal hematoma, encompassing the extrastriate cortex adjoining the inferior parietal lobe. This new case suggests that: (i) agnosia for mirror stimuli can persist for 5 years after onset and (ii) the posterior part of the right intraparietal sulcus could be critical in the cognitive process of mirror stimuli discrimination.