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Abstract: A new Q555X mutation on the SYN1 gene was recently found in several members of a family segregating dyslexia, epilepsy, and autism spectrum disorder. To describe the effects of this mutation on cortical gray matter microstructure, we performed a surface‐based group study using novel diffusion and quantitative multiparametric imaging on 13 SYN1Q555X mutation carriers and 13 age‐ and sex‐matched controls. Specifically, diffusion kurtosis imaging (DKI) and neurite orientation and dispersion and density imaging (NODDI) were used to analyze multi‐shell diffusion data and obtain parametric maps sensitive to tissue structure, while quantitative metrics sensitive to tissue composition (T1, T2* and relative proton density [PD]) were obtained from a multi‐echo variable flip angle FLASH acquisition. Results showed significant microstructural alterations in several regions usually involved in oral and written language as well as dyslexia. The most significant changes in these regions were lowered mean diffusivity and increased fractional anisotropy. This study is, to our knowledge, the first to successfully use diffusion imaging and multiparametric mapping to detect cortical anomalies in a group of subjects with a well‐defined genotype linked to language impairments, epilepsy and autism spectrum disorder (ASD). [ABSTRACT FROM AUTHOR]

Background: Mild cognitive impairment (MCI) is a condition considered by many as a transitional stage between healthy aging and Alzheimer's disease. Although its diagnosis is typically based on the assessment of episodic memory, evidences show that impairment in semantic memory would be one of the first manifestations of cognitive impairment. This study aims to investigate how semantic memory is affected in MCI. Precisely, we will explore if core memory of common knowledge is impaired in MCI, and if the performance in semantic memory task vary with the modality of presentation of the stimuli (verbal vs visual). Method: A group of healthy people aged between 60 and 90 years old (mean: 77.4 N = 43), and a age‐matched group meeting the criteria for MCI (N = 32), who have lived in Quebec (Canada) for at least 30 years, completed two neuropsychological tests evaluating the semantic memory of famous people, which have been proven to be the most sensible way to detect even subtle variation in semantic memory. Result: Results indicate that performance in both tests is impaired in the MCI group, compared to the healthy elderly group. This means that the MCI group have more difficulty to name famous people (t (69) = 5,173, p < 0.01), as well as answer basic questions on them (ex: their profession, nationality, etc.), when presented from their picture (t (69) = 4.849, p < 0.01) or their name (t (65) = 3.488, p < 0.01), compared to healthy people of the same age. There was no difference between their performances when the stimuli was presented in the visual or verbal modality (t (30) = 0.928, p > 0.05). Conclusion: This study demonstrates that semantic memory of famous people is impaired in MCI, and that impairment affects the capacity to name famous people as well as remembering facts about them. In addition, there are no difference if the stimuli are presented visually or verbally. This suggests that the impairment in semantic memory in MCI is due to a degradation of the memory, and is not modulated by other cognitive functions or modality. [ABSTRACT FROM AUTHOR]

Objective We recently reported a Q555X mutation of synapsin 1 ( SYN1) on chromosome Xp11-q21 in a family segregating partial epilepsy and autistic spectrum disorder. Herein, we provide a detailed description of the epileptic syndrome in the original family. Methods A total of 34 members from a large French-Canadian family were evaluated. Family members with seizures or epilepsy underwent (when possible) clinical, neuropsychological, electrophysiologic, and neuroimaging assessments. Results Epilepsy was diagnosed in 10 family members (4 deceased, 6 living). In addition to occasional spontaneous complex partial seizures, seven family members clearly had reflex seizures triggered by bathing or showering. Hippocampal atrophy was found in two of five epileptic family members family members who underwent magnetic resonance (MR) imaging. Video-electroencephalography (EEG) recordings of three triggered seizures in two affected members showed rhythmic theta activity over temporal head regions. Ictal single-photon emission computed tomography (SPECT) showed temporoinsular perfusion changes. Detailed neuropsychological assessments revealed that SYN1 Q555X male mutation carriers showed specific language impairment and mild autistic spectrum disorder. Female carriers also exhibited reading impairments and febrile seizures but no chronic epilepsy. Significance Available evidence suggests that impaired SYN1 function is associated with hyperexcitability of the temporoinsular network and disturbance of high mental functions such as language and social interaction. The presence of reflex bathing seizures, a most peculiar clinical feature, could be helpful in identifying other patients with this syndrome. [ABSTRACT FROM AUTHOR]

Organic and psychogenic retrograde amnesia have long been considered as distinct entities and as such, studied separately. However, patterns of neuropsychological impairments in organic and psychogenic amnesia can bear interesting resemblances despite different aetiologies. In this paper, two cases with profound, selective and permanent retrograde amnesia are presented, one of an apparent organic origin and the other with an apparent psychogenic cause. The first case, DD, lost his memory after focal brain injury from a nail gun to the right temporal lobe. The second case, AC, lost her memory in the context of intense psychological suffering. In both cases, pre-morbid autobiographical memory for people, places and events was lost, and no feeling of familiarity was experienced during relearning. In addition, they both lost some semantic knowledge acquired prior to the onset of the amnesia. This contrasts with the preservation of complex motor skills without any awareness of having learned them. Both DD and AC showed mild deficits on memory tests but neither presented any anterograde amnesia. The paradox of these cases – opposite causes yet similar clinical profile – exemplifies the hypothesis that organic and psychogenic amnesia may be two expressions of the same faulty mechanism in the neural circuitry. [ABSTRACT FROM AUTHOR]

Theory of mind (ToM) deficits have been reported in persons with multiple sclerosis (pwMS). However, most studies have used pictures or written scenarios as stimuli without distinguishing between cognitive and affective ToM, and no studies have investigated older pwMS. We recruited 13 young healthy controls (HC), 14 young pwMS, 14 elderly HC and 15 elderly pwMS. ToM was measured using an adaptation of the Conversations and Insinuations task (Ouellet et al., J. Int. Neuropsychol. Soc., 16, 2010, 287). In this ecological video‐based task, participants watch four 2‐minute videos of social interactions, which are interrupted by multiple choice questions about either the emotional state (affective ToM) or the intention (cognitive ToM) of the characters. They also underwent a short neuropsychological battery including cognitive, executive and social cognition tasks and questionnaires. We observed a significant interaction between the ToM conditions and the groups regarding ToM performance. Elderly pwMS scored significantly lower than elderly HC and young pwMS in cognitive ToM, but not in affective ToM. They also showed the largest discrepancy between their cognitive and affective ToM. Young pwMS showed relatively preserved ToM in both conditions. Both cognitive and affective ToM correlated with global cognition and executive abilities, but not with social cognitive measures (emotion recognition, real‐life empathy). This study suggests that decline in cognitive ToM might be accentuated by advancing age in pwMS. These impairments are most likely underlied by cognitive and executive difficulties, but not by core social cognitive impairments. Future studies should investigate the real‐life impacts of ToM impairments in pwMS. [ABSTRACT FROM AUTHOR]