The multiscale topological organization of the functional brain network in adolescent PTSD.

The experience of an extremely aversive event can produce enduring deleterious behavioral, and neural consequences, among which posttraumatic stress disorder (PTSD) is a representative example. Although adolescence is a period of great exposure to potentially traumatic events, the effects of trauma during adolescence remain understudied in clinical neuroscience. In this exploratory work, we aim to study the whole-cortex functional organization of 14 adolescents with PTSD using a data-driven method tailored to our population of interest. To do so, we built on the network neuroscience framework and specifically on multilayer (multisubject) community analysis to study the functional connectivity of the brain. We show, across different topological scales (the number of communities composing the cortex), a hyper-colocalization between regions belonging to occipital and pericentral regions and hypo-colocalization in middle temporal, posterior-anterior medial, and frontal cortices in the adolescent PTSD group compared to a nontrauma exposed group of adolescents. These preliminary results raise the question of an altered large-scale cortical organization in adolescent PTSD, opening an interesting line of research for future investigations.

Alterations in resting-state functional connectivity associated to the age-related decline in time-based prospective memory.

Time-based prospective memory (TBPM) is defined as the ability to remember to perform intended actions at a specific time in the future. TBPM is impaired in aging, and this decline has been associated with white-matter alterations within the superior fronto-occipital fasciculus. In the present study, we used resting-state functional magnetic resonance imaging from 22 healthy young (26 ± 5.2 years) and 23 older (63 ± 6.1 years) participants to investigate how age-related alterations in resting-state functional connectivity are related to TBPM performance, and whether these alterations are associated with the white-matter disruptions we have previously observed with diffusion tensor imaging. Whole-brain analyses revealed lower resting-state functional connectivity in older participants compared with younger ones, which in turn correlated with TBPM performance. These correlations were mainly located in the salience network and the parietal part of the frontoparietal network. Our findings suggest that resting-state functional connectivity alterations contribute to the age-related decline in TBPM.

Effects of sleep disturbances and circadian rhythms modifications on cognition in breast cancer women before and after adjuvant chemotherapy: the ICANSLEEP-1 protocol.

BACKGROUND: Many patients treated for breast cancer (BC) complain about cognitive difficulties affecting their daily lives. Recently, sleep disturbances and circadian rhythm disruptions have been brought to the fore as potential contributors to cognitive difficulties in patients with BC. Yet, studies on these factors as well as their neural correlates are scarce. The purpose of the ICANSLEEP-1 (Impact of SLEEP disturbances in CANcer) study is to characterize sleep using polysomnography and its relationship with the evolution of cognitive functioning at both the behavioral and the neuroanatomical levels across treatment in BC patients treated or not with adjuvant chemotherapy. METHODS: ICANSLEEP-1 is a longitudinal study including BC patients treated with adjuvant chemotherapy (n = 25) or not treated with adjuvant chemotherapy (n = 25) and healthy controls with no history of BC (n = 25) matched for age (45-65 years old) and education level. The evaluations will take place within 6 weeks after inclusion, before the initiation of chemotherapy (for BC patients who are candidates for chemotherapy) or before the first fraction of radiotherapy (for BC patients with no indication for chemotherapy) and 6 months later (corresponding to 2 weeks after the end of chemotherapy). Episodic memory, executive functions, psychological factors, and quality of life will be assessed with validated neuropsychological tests and self-questionnaires. Sleep quantity and quality will be assessed with polysomnography and circadian rhythms with both actigraphy and saliva cortisol. Grey and white matter volumes, as well as white matter microstructural integrity, will be compared across time between patients and controls and will serve to further investigate the relationship between sleep disturbances and cognitive decline. DISCUSSION: Our results will help patients and clinicians to better understand sleep disturbances in BC and their relationship with cognitive functioning across treatment. This will aid the identification of more appropriate sleep therapeutic approaches adapted to BC patients. Improving sleep in BC would eventually help limit cognitive deficits and thus improve quality of life during and after treatments. TRIAL REGISTRATION: NCT05414357, registered June 10, 2022. PROTOCOL VERSION: Version 1.2 dated March 23, 2022.

Self-referential processes and resting-state connectivity in breast cancer patients before and 1 year after chemotherapy.

Modifications in the processing of information relevant to oneself have been reported in breast cancer (BC) patients. Here, we characterize the longitudinal changes to self-representations in BC patients and how they are related to intrinsic functional brain connectivity. We tested 16 BC patients before (T1) and 1 year after the end of chemotherapy (T2) along with 24 healthy control participants (HC) at similar time points. Participants underwent resting-state fMRI and completed the Questionnaire of Self-Representation (QSR), which evaluates self-assertion and self-esteem. Resting-state functional connectivity (RSFC) was calculated for regions implicated in self-referential processes (dorsomedial prefrontal cortex [dmPFC], posterior cingulate cortex [PCC], and dorsal anterior cingulate cortex [dACC]) and correlated with QSR scores. QSR scores were on average larger in patients compared with HC and did not vary over time. RSFC between the dACC and regions supporting body awareness (precentral/postcentral and supramarginal gyri, superior parietal lobule) decreased more between T1 and T2 in BC patients than in HC. BC patients had lower RSFC than HC between the dmPFC and the PCC, and regions supporting mental imagery (precuneus, lingual gyrus), at each time point, and a greater decrease from T1 and T2. QSR scores negatively correlated with RSFC. Patients described themselves as having greater self-awareness and positive self-image, reflecting a fighting spirit. In parallel, patients presented a decrease in cortical activity related to body awareness and mental imagery of self-representations over time that may be related to the positive self-image patients have and could reflect a temporary adaptive strategy.

Longitudinal Changes in Hippocampal Network Connectivity in Alzheimer's Disease.

OBJECTIVE: The hippocampus is connected to 2 distinct cortical brain networks, the posterior-medial and the anterior-temporal networks, involving different medial temporal lobe (MTL) subregions. The aim of this study was to assess the functional alterations of these 2 networks, their changes over time, and links to cognition in Alzheimer's disease. METHODS: We assessed MTL connectivity in 53 amyloid-ß-positive patients with mild cognitive impairment and AD dementia and 68 healthy elderly controls, using resting-state functional magnetic resonance imaging, cross-sectionally and longitudinally. First, we compared the functional connectivity of the posterior-medial and anterior-temporal networks within the control group to highlight their specificities. Second, we compared the connectivity of these networks between groups, and between baseline and 18-month follow-up in patients. Third, we assessed the association in the connectivity changes between the 2 networks, and with cognitive performance. RESULTS: We found decreased connectivity in patients specifically between the hippocampus and the posterior-medial network, together with increased connectivity between several MTL subregions and the anterior-temporal network. Moreover, changes in the posterior-medial and anterior-temporal networks were interrelated such that decreased MTL-posterior-medial connectivity was associated with increased MTL-anterior-temporal connectivity. Finally, both MTL-posterior-medial decrease and MTL-anterior-temporal increase predicted cognitive decline. INTERPRETATION: Our findings demonstrate that longitudinal connectivity changes in the posterior-medial and anterior-temporal hippocampal networks are linked together and that they both contribute to cognitive decline in Alzheimer's disease. These results shed light on the critical role of the posterior-medial and anterior-temporal networks in Alzheimer's disease pathophysiology and clinical symptoms. ANN NEUROL 2021;90:391-406.

Brain Substrates of Time-Based Prospective Memory Decline in Aging: A Voxel-Based Morphometry and Diffusion Tensor Imaging Study.

Time-based prospective memory (TBPM) allows us to remember to perform intended actions at a specific time in the future. TBPM is sensitive to the effects of age, but the neural substrates of this decline are still poorly understood. The aim of the present study was thus to better characterize the brain substrates of the age-related decline in TBPM, focusing on macrostructural gray matter and microstructural white matter integrity. We administered a TBPM task to 22 healthy young (26 ± 5.2 years) and 23 older (63 ± 5.9 years) participants, who also underwent volumetric magnetic resonance imaging and diffusion tensor imaging scans. Neuroimaging analyses revealed lower gray matter volumes in several brain areas in older participants, but these did not correlate with TBPM performance. By contrast, an age-related decline in fractional anisotropy in several white-matter tracts connecting frontal and occipital regions did correlate with TBPM performance, whereas there was no significant correlation in healthy young subjects. According to the literature, these tracts are connected to the anterior prefrontal cortex and the thalamus, 2 structures involved in TBPM. These results confirm the view that a disconnection process occurs in aging and contributes to cognitive decline.

When affect overlaps with concept: emotion recognition in semantic variant of primary progressive aphasia.

The most recent theories of emotions have postulated that their expression and recognition depend on acquired conceptual knowledge. In other words, the conceptual knowledge derived from prior experiences guide our ability to make sense of such emotions. However, clear evidence is still lacking to contradict more traditional theories, considering emotions as innate, distinct and universal physiological states. In addition, whether valence processing (i.e. recognition of the pleasant/unpleasant character of emotions) also relies on semantic knowledge is yet to be determined. To investigate the contribution of semantic knowledge to facial emotion recognition and valence processing, we conducted a behavioural and neuroimaging study in 20 controls and 16 patients with the semantic variant of primary progressive aphasia, a neurodegenerative disease that is prototypical of semantic memory impairment, and in which an emotion recognition deficit has already been described. We assessed participants' knowledge of emotion concepts and recognition of 10 basic (e.g. anger) or self-conscious (e.g. embarrassment) facial emotional expressions presented both statically (images) and dynamically (videos). All participants also underwent a brain MRI. Group comparisons revealed deficits in both emotion concept knowledge and emotion recognition in patients, independently of type of emotion and presentation. These measures were significantly correlated with each other in patients and with semantic fluency in patients and controls. Neuroimaging analyses showed that both emotion recognition and emotion conceptual knowledge were correlated with reduced grey matter density in similar areas within frontal ventral, temporal, insular and striatal regions, together with white fibre degeneration in tracts connecting frontal regions with each other as well as with temporal regions. We then performed a qualitative analysis of responses made during the facial emotion recognition task, by delineating valence errors (when one emotion was mistaken for another of a different valence), from other errors made during the emotion recognition test. We found that patients made more valence errors. The number of valence errors correlated with emotion conceptual knowledge as well as with reduced grey matter volume in brain regions already retrieved to correlate with this score. Specificity analyses allowed us to conclude that this cognitive relationship and anatomical overlap were not mediated by a general effect of disease severity. Our findings suggest that semantic knowledge guides the recognition of emotions and is also involved in valence processing. Our study supports a constructionist view of emotion recognition and valence processing, and could help to refine current theories on the interweaving of semantic knowledge and emotion processing.

Self-awareness in Transient Global Amnesia: distinguishing the effects of transient memory disorder vs. pre-existing vulnerability factors.

Numerous evidences suggest the existence of relationships between the impairment of episodic memory, acute stress exposure and variations in self-awareness (SA). Here, we examined 27 patients presenting transient global amnesia (TGA), a clinical condition which combines episodic amnesia and high anxiety, thanks to state and trait questionnaires of SA. We observed variation of SA depending on the stage of TGA (acute, recovery and follow-up). We also found preexisting differences in patient's awareness of their own image when the precipitating event was physical, encouraging us to give more consideration to the social determinants of stress in physiological cascade of TGA.

Changes over 10 years in the retelling of the flashbulb memories of the attack of 11 September 2001.

A flashbulb memory is a highly detailed and vivid autobiographical memory for the circumstances in which one first learned of a surprising, consequential and emotionally arousing event. How retelling of different features of a flashbulb memory changes over time is not totally understood. Moreover, little is known about how the emotional feeling experienced by individuals when they learned about the event modulates these changes. In this study, we explored changes over time in American individuals' retelling of their flashbulb memories of the terrorist attack of 11 September 2001. We conducted textual analysis of 824 testimonies collected from the same 206 individuals 1 week, 11, 25 and again 119 months after the attack. Results showed individuals were more likely to report temporal and emotional details in their retelling early after the event and spatial details in their long-term retelling. In addition, the intensity of emotions felt upon hearing the news about the attack influenced how individuals reported their flashbulb memories over time. Overall, this study provides further support for theories suggesting different rates of forgetting for different canonical features of emotional arousal events.

Influence of emotional complexity on the neural substrates of affective theory of mind.

Affective theory of mind (ToM) depends on both the decoding of emotional expressions and the reasoning on emotional mental states from social situations. While previous studies characterized the neural substrates underlying these processes, it remains unclear whether the nature of the emotional state inferred from others can influence the brain activation associated with affective ToM. In the present study, we focused on two types of emotions: basic emotions (BEs) (e.g., anger and surprise), which are innate and universal and self-conscious emotions (e.g., pride and embarrassment), which correspond to a special class of emotions involving the self and including a representation of one's relative reactions to internal and external standards. Specifically, we used an ecological functional MRI paradigm, on 21 healthy young subjects, to compare brain activations during the decoding of and the reasoning on others' self-conscious, basic and neutral mental states. Our results showed that compared to neutral states, the inference of self-conscious and basic emotional states from others elicited more activation in several core regions of affective ToM. Direct comparisons between emotional conditions revealed more activation for self-conscious than BEs in the right temporoparietal junction during the reasoning process and in left middle occipital regions during the decoding process. Further analyses using a localizer task showed that the extrastriate body area was more recruited for decoding others' self-conscious versus BEs, which emphasize the importance of body clues to properly infer these emotions. Using an original task allowing for an ecological assessment of the affective ToM, these results demonstrate that the complexity of the emotion inferred to others can influence the recruitment of ToM network. This study also validates the use of our task as an ecological tool to assess the affective ToM, constituting an avenue for the characterization of ToM impairments in neurological conditions.

Dissociating thalamic alterations in alcohol use disorder defines specificity of Korsakoff's syndrome.

The thalamus, a relay organ consisting of several nuclei, is shared between the frontocerebellar circuit and the Papez circuit, both particularly affected in alcohol use disorder. Shrinkage of the thalamus is known to be more severe in alcoholics with Korsakoff's syndrome than in those without neurological complications (uncomplicated alcoholics). While thalamic atrophy could thus be a key factor explaining amnesia in Korsakoff's syndrome, the loci and nature of alterations within the thalamic nuclei in uncomplicated alcoholics and alcoholics with Korsakoff's syndrome remains unclear. Indeed, the literature from animal and human models is disparate regarding whether the anterior thalamic nuclei, or the mediodorsal nuclei are particularly affected and would be responsible for amnesia. Sixty-two participants (20 healthy controls, 26 uncomplicated alcoholics and 16 patients with Korsakoff's syndrome) underwent a diffusion tensor imaging sequence and T1-weighted MRI. State-of-the-art probabilistic tractography was used to segment the thalamus according to its connections to the prefrontal cortex and cerebellar Cruses I and II for the frontocerebellar circuit's executive loop, the precentral gyrus and cerebellar lobes IV-VI for the frontocerebellar circuit's motor loop, and hippocampus for the Papez circuit. The connectivity and volumes of these parcellations were calculated. Tractography showed that the hippocampus was principally connected to the anterior thalamic nuclei while the prefrontal cortex was principally connected to the mediodorsal nuclei. The fibre pathways connecting these brain regions and their respective thalamic nuclei have also been validated. ANCOVA, with age and gender as covariates, on connectivity measures showed abnormalities in both patient groups for thalamic parcellations connected to the hippocampus only [F(2,57) = 12.1; P < 0.0001; η2 = 0.2964; with graded effects of the number of connections from controls to uncomplicated alcoholics to Korsakoff's syndrome]. Atrophy, on the other hand, was observed for the prefrontal parcellation in both patient groups and to the same extent compared to controls [F(2,56) = 18.7; P < 0.0001; η2 = 0.40]. For the hippocampus parcellation, atrophy was found in the Korsakoff's syndrome group only [F(2,56) = 5.5; P = 0.006; η2 = 0.170, corrected for multiple comparisons using Bonferroni, P < 0.01]. Post hoc Tukey's test for unequal sample sizes, healthy controls > patients with Korsakoff's syndrome (P = 0.0036). Two different mechanisms seem to affect the thalamus. In the frontocerebellar circuit, atrophy of the mediodorsal nuclei may lead to the alterations, whereas in the Papez circuit, disconnection between the anterior nuclei and hippocampus may be the leading factor. Shrinkage of the anterior nuclei could be specific to patients with Korsakoff's syndrome, hence a potential neuroimaging marker of its pathophysiology, or more generally of thalamic amnesia for which Korsakoff's syndrome has historically been used as a model.

Specific cognitive theory of mind and behavioral dysfunctions in early manifest Huntington disease: a case report.

Huntington's disease (HD) is a devastating illness, associated with progressive motor, behavioral and cognitive dysfunctions. However, some studies emphasized that social cognition impairment could occur prior to the onset of these other symptoms. Here, we report the case of a 47 years old patient with early manifest HD, whose complaint was mainly related to the behavioral sphere. He exhibited a significant impairment of Theory of Mind abilities as well as behavioral, and discrete motor symptoms without noticeable cognitive decline. This case study suggests that social cognition impairments and behavioral changes could be in some cases a feature of the disease and may represent a major disability, in early stages of manifest HD.

Distinct Interplay Between Atrophy and Hypometabolism in Alzheimer's Versus Semantic Dementia.

Multimodal neuroimaging analyses offer additional information beyond that provided by each neuroimaging modality. Thus, direct comparisons and correlations between neuroimaging modalities allow revealing disease-specific topographic relationships. Here, we compared the topographic discrepancies between atrophy and hypometabolism in two neurodegenerative diseases characterized by distinct pathological processes, namely Alzheimer's disease (AD) versus semantic dementia (SD), to unravel their specific influence on local and global brain structure-function relationships. We found that intermodality topographic discrepancies clearly distinguished the two patient groups: AD showed marked discrepancies between both alterations, with greater hypometabolism than atrophy in large posterior associative neocortical regions, while SD showed more topographic consistency between atrophy and hypometabolism across brain regions. These findings likely reflect the multiple pathologies versus the relatively unitary pathological process underlying AD versus SD respectively. Our results evidence that multimodal neuroimaging-derived indexes can provide clinically relevant information to discriminate the two diseases, and potentially reveal distinct neuropathological processes.

Cognitive Changes After Adjuvant Treatment in Older Adults with Early-Stage Breast Cancer.

BACKGROUND: Group-based trajectory modeling is particularly important to identify subgroups of patients with pathological cognitive changes after cancer treatment. To date, only one study has explored cognitive trajectories in older patients with cancer. The present article describes objective cognitive changes before to after adjuvant treatment in older adults with early-stage breast cancer (EBC) after adjuvant treatment compared with healthy controls. PATIENTS AND METHODS: Participants were patients ≥65 years of age with newly diagnosed EBC and healthy controls (age-, sex-, and education-matched). The pretreatment assessment was conducted before adjuvant therapy, and the post-treatment assessment after the end of the first adjuvant treatment. Objective cognitive changes before to after treatment were evaluated based on the Reliable Change Index for cognitive decline accounting for cognitive impairment status. RESULTS: The sample consisted of women newly diagnosed with EBC (n = 118) and healthy controls (n = 62). Five patterns of changes before to after treatment were identified based on the presence of cognitive decline and cognitive impairment. The distribution of these five change patterns was statistically significant (p = .0001). Thirty-six percent of patients had phase shift changes, 31% without initial objective cognitive impairment developed impairment, 15% had a normal aging, 12% had a nonpathological decline, and 6% experienced accelerated cognitive decline. CONCLUSION: This study described for the first time objective cognitive changes before to after treatment of older adults with EBC immediately after the end of adjuvant treatment. A longer-term remote follow-up of adjuvant treatment is needed to better understand the cognitive trajectories of older patients with EBC. IMPLICATIONS FOR PRACTICE: After the end of adjuvant treatment, 31% of older adults with early-stage breast cancer without initial objective cognitive impairment developed impairment, and 6% experienced accelerated cognitive decline. Initial cognitive functioning should be included in the balance of benefits and harms of systemic therapy for patients who are likely to be at highest risk for cognitive decline after cancer treatments. Regular cognitive follow-up of patients who had cognitive impairment before cancer treatment should monitor symptoms suggestive of neurodegenerative disease and avert the effect of cognitive disorders on patients' autonomy.

Hippocampal subfields alterations in adolescents with post-traumatic stress disorder.

Reexperiencing symptoms in adolescent Post-Traumatic Stress Disorder (PTSD) are characterized by the apparition of vivid intrusive images of the traumatic event. The emergence of these intrusions is thought to be related to a deficiency in context processing and could then be related to hippocampal alterations. The hippocampus is a complex structure which can be divided into several subfields, namely, the Cornu Ammonis (CA1, CA2, and CA3), the subiculum, and the dentate gyrus (DG). As each subfield presents different histological characteristics and functions, it appears more relevant to consider hippocampal subfields, instead of only assessing the whole hippocampus, to understand the neurobiology of PTSD. Hence, this study presents the first investigation of structural alterations within hippocampal subfields and their links to reexperiencing symptoms in adolescent PTSD. Hippocampal subfields were manually delineated on high-resolution MRI images in 15 adolescents (13-18 years old) with PTSD and 24 age-matched healthy controls. The volume of the region CA2-3/DG region was significantly smaller in the PTSD group compared to controls in both hemispheres. No other significant difference was found for other subfields. Moreover, the volume of the left CA2-3/DG was negatively correlated with the intrusion score (as measured by the Impact of Events Scale-Revised) in the PTSD group. To conclude, an alteration in the hippocampal subregion CA2-3/DG, known to resolve interferences between new and similar stored memories, could participate in the apparition of intrusive trauma memories in adolescents with PTSD.

Cerebellar Hypermetabolism in Alcohol Use Disorder: Compensatory Mechanism or Maladaptive Plasticity?

BACKGROUND: Despite severe structural brain abnormalities within the frontocerebellar circuit (FCC), cerebellar metabolism studied with 18 F-2-fluoro-deoxy-glucose-positron emission tomography (FDG-PET) is relatively preserved in patients with alcohol use disorder (AUD). The compensatory role of the cerebellum has been explored mainly through fMRI examination of AUD patients with the preserved level of performance. The present study aims at examining cerebellar metabolism and its relationship with regional brain metabolism and neuropsychological functioning in AUD patients. METHODS: Thirty-two recently detoxified AUD patients and 23 controls underwent an FDG-PET examination at rest. Participants also performed a neuropsychological battery assessing executive functions, verbal memory, and ataxia. RESULTS: Compared to controls, AUD patients had higher glucose uptake in the cerebellar lobule VIII, in association with hypometabolism, notably in several nodes of the FCC. Cerebellar hypermetabolism correlated negatively with regional hypometabolism in the premotor and frontal cortices. This pattern of regional hypermetabolism and hypometabolism related to ataxia and working memory deficits. CONCLUSIONS: These specific brain-behavior relationships do not fulfill the criteria for brain compensatory processes. Cerebellar hypermetabolism may rather reflect the involvement of different pathological mechanisms, leading to a maladaptive plasticity phenomenon within the FCC in AUD patients who are early in abstinence. Further studies are required to examine the contributions of structural and functional connectivity alterations in the cerebellar hypermetabolism and the changes in these pathological mechanisms with abstinence or relapse.

Neuropsychological and Neuroimaging Examinations of Self-Reported Sleep Quality in Alcohol Use Disorder With and Without Korsakoff's Syndrome.

BACKGROUND: Alcohol use disorder (AUD) patients without Korsakoff's syndrome (KS) report a variable self-rated sleep quality. Their ability to accurately judge their sleep quality may be related to their alcohol-related cognitive deficits and brain damage. KS patients, who present severe brain dysfunction, may be cognitively unable to judge their sleep quality. The aim of the present study is to examine, in AUD and KS patients, whether the absence of sleep complaint is associated with altered brain structure and impaired cognitive abilities within specific cerebral networks. METHODS: An assessment of subjective sleep quality was conducted in 20 healthy controls, 37 AUD patients, and 17 KS patients. Patients were first pooled together and then classified into 2 groups (no-complaintAUD + KS and complaintAUD + KS ) according to the total Pittsburg Sleep Quality Index score. Cognitive scores, gray matter (GM) volume, and white matter (WM) integrity were compared between these 2 groups, and then in AUD and KS patients separately. RESULTS: Poor sleep quality was reported by 70% of AUD and 18% of KS patients. Compared to controls, both no-complaintAUD + KS and complaintAUD + KS presented cortical and subcortical alterations as well as episodic memory deficits, which were more severe in patients without sleep complaint. Only no-complaintAUD + KS presented executive deficits. Then, considering the clinical diagnosis, GM volume in frontotemporal regions, WM integrity, and executive functions were affected to the same extent in AUD and KS patients without sleep complaint. CONCLUSIONS: Our results confirm the high prevalence of sleep complaint in AUD patients and the rare complaint in KS patients. In AUD and KS patients, the absence of sleep complaint may not indicate good sleep quality but rather reflect executive deficits and frontothalamic damage. Alcohol-related cognitive deficits may indeed alter the ability to self-evaluate sleep quality, suggesting that the use of sleep questionnaire should be considered with caution in patients with executive deficits.

Neurocognitive determinants of theory of mind across the adult lifespan.

Although theory of mind (ToM) has been extensively explored in aging, few studies have used the same tool to simultaneously assess and compare its cognitive and affective components. When we administered the Movie for Assessment of Social Cognition, a dynamic sequence of social scenes, to 60 healthy participants (20-75 years), we observed no different age-related decreases in both cognitive and affective ToM. While each component was associated with cognitive measures (i.e., episodic memory and processing speed were predictive of cognitive ToM, and recognition of facial emotion expressions and inhibition were predictive of affective ToM), mediation analyses showed that these measures only mediated the effect of age on affective ToM. Voxelwise regressions with grey-matter volume showed that the components partly rely on the same neural substrates, reflecting either ToM per se or other cognitive processes elicited by this multi-determinant task. We discuss the specific substrates of each ToM component, emphasising the importance of considering the impact of other aspects of cognition, present in more ecological situations, on ToM functioning.

Impact of breast cancer on prospective memory functioning assessed by virtual reality and influence of sleep quality and hormonal therapy: PROSOM-K study.

BACKGROUND: Breast cancer (BC) is the most frequent cancer in women with more than 70% of BC patients being treated with hormonal therapy (HT). Among these patients, some report difficulties in remembering what they are supposed to do at the right moment, referring to prospective memory (PM). PM is essential for autonomy and medical adherence of patients, and requires an ecological assessment. Virtual reality, that recreates naturalistic environment, seems to be a promising method to evaluate PM. Several BC patients also report sleep disturbances. Given the role of sleep on memory consolidation, it is imperative to explore the influence of sleep quality on PM in BC patients treated with HT. The purpose of PROSOM-K study is to assess PM functioning using virtual reality and sleep quality in BC treated or not with HT. METHODS: PROSOM-K is a prospective study including post-menopausal BC patients ≤70 years old treated with radiotherapy (n = 25) or with radiotherapy and HT (n = 25), and healthy post-menopausal women (n = 25) matched for age and education. PM will be assessed using a virtual reality based task. Other cognitive functions and psychosocial factors will be assessed with validated questionnaires and neuropsychological tests. The study is divided in 3 sessions: a session of familiarisation with the virtual environment and the PM task: a day-time session during which participants learn intentions during the morning and recall them in the evening; and a night-time session during which participants learn intentions in the evening and recall them the following morning. Women will be monitored by wrist actigraphy; during the night-time session, objective sleep quality and quantity will be measured by polysomnography. DISCUSSION: This is a novel study aiming to assess PM using virtual reality, coupled with the evaluation of other cognitive functions. Polysomnographic study of sleep will provide further information about architectural sleep disturbances in BC. Association between sleep architecture parameters and PM mechanism in BC women treated with HT will be described in detail. We expect our results will provide knowledge for patients and clinicians and further help to improve patient care and cognitive therapy. TRIAL REGISTRATION: NCT03420105 , registered: January 10, 2018.

Distinct white matter injury associated with medial temporal lobe atrophy in Alzheimer's versus semantic dementia.

This study aims at further understanding the distinct vulnerability of brain networks in Alzheimer's disease (AD) versus semantic dementia (SD) investigating the white matter injury associated with medial temporal lobe (MTL) atrophy in both conditions. Twenty-six AD patients, twenty-one SD patients, and thirty-nine controls underwent a high-resolution T1-MRI scan allowing to obtain maps of grey matter volume and white matter density. A statistical conjunction approach was used to identify MTL regions showing grey matter atrophy in both patient groups. The relationship between this common grey matter atrophy and white matter density maps was then assessed within each patient group. Patterns of grey matter atrophy were distinct in AD and SD but included a common region in the MTL, encompassing the hippocampus and amygdala. This common atrophy was associated with alterations in different white matter areas in AD versus SD, mainly including the cingulum and corpus callosum in AD, while restricted to the temporal lobe - essentially the uncinate and inferior longitudinal fasciculi - in SD. Complementary analyses revealed that these relationships remained significant when controlling for global atrophy or disease severity. Overall, this study provides the first evidence that atrophy of the same MTL region is related to damage in distinct white matter fibers in AD and SD. These different patterns emphasize the vulnerability of distinct brain networks related to the MTL in these two disorders, which might underlie the discrepancy in their symptoms. These results further suggest differences between AD and SD in the neuropathological processes occurring in the MTL. Hum Brain Mapp 38:1791-1800, 2017. © 2017 Wiley Periodicals, Inc.