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.

Intact memory storage but impaired retrieval in visual memory in autism: New insights from an electrophysiological study.

In a recent study on visual episodic memory (Desaunay, Clochon, et al., 2020), we have shown event-related potentials (ERPs) differences associated with priming (150-300 msec), familiarity (350-470 msec), and recollection (600-700 msec), in young people with autism spectrum disorders (ASD) compared with typical development (TD). To go further into the study of the processes of storage and retrieval of the memory trace, we re-analyzed Desaunay, Clochon, et al's data using time-frequency analysis, that is, event-related synchronization and desynchronization (ERS/ERD). This allows a decomposition of the spectral power within frequency bands associated with these ERPs. We focused both on the same time windows and the same regions of interest as previously published. We mainly identified, in ASD compared with TD, reduced ERS in low-frequencies (delta, theta) in early time-windows, and non-significant differences in ERD in higher frequencies (alpha, beta1) in all time-windows. Reduced ERS during recognition confirmed previously reported diminution of priming effects and difficulties in manipulation and retrieval of both semantic and episodic information. Conversely, preserved ERD corroborates a preservation of memory storage processes. These observations are consistent with a cognitive model of memory in ASD, that suggests difficulties in cognitive operations or executive demand at retrieval, subsequent to successful long-term storage of information. LAY SUMMARY: We assessed the EEG synchronization and desynchronization, during visual episodic recognition. We observed, in youth with Autism, reduced synchronization in low-frequencies (delta, theta), suggesting reduced access to and manipulation of long-term stored information. By contrast, non-significant differences in desynchronization at higher frequencies (alpha, beta frequency bands), that support long-term stored semantic and episodic information, suggested preserved memory traces.

Attentional capture mediates the emergence and suppression of intrusive memories.

Intrusive memories hijack consciousness and their control may lead to forgetting. However, the contribution of reflexive attention to qualifying a memory signal as interfering is unknown. We used machine learning to decode the brain's electrical activity and pinpoint the otherwise hidden emergence of intrusive memories reported during a memory suppression task. Importantly, the algorithm was trained on an independent attentional model of visual activity, mimicking either the abrupt and interfering appearance of visual scenes into conscious awareness or their deliberate exploration. Intrusion of memories into conscious awareness were decoded above chance. The decoding accuracy increased when the algorithm was trained using a model of reflexive attention. Conscious detection of intrusive activity decoded from the brain signal was central to the future silencing of suppressed memories and later forgetting. Unwanted memories require the reflexive orienting of attention and access to consciousness to be suppressed effectively by inhibitory control.

Longitudinal grey matter and metabolic contributions to cognitive changes in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis is characterized by rapidly evolving cognitive and brain impairments. While previous work revealed structural and functional alterations associated with cognitive decline in patients suffering from amyotrophic lateral sclerosis, the relationships between anatomo-functional changes and both disease's progression and the evolution of cognitive performance remain largely unexplored. Here, we took advantage of repeated multi-modal acquisitions in patients with amyotrophic lateral sclerosis over 1 year to assess the longitudinal sequence of grey matter atrophy, glucose metabolism and cognitive changes. Results revealed metabolic and structural changes over frontal, thalamic and temporal regions. Both cortical hypermetabolism and hypometabolism (right temporal gyrus and right angular gyrus, respectively) were associated with cognitive performance and thalamic hypometabolism during the follow-up testing session. Furthermore, the inferior frontal gyrus atrophy mediated the relation between early hypometabolism in this region and the subsequent decline of the theory of mind abilities. Marked volume loss was associated with larger hypometabolism and impaired cognitive performance. To our knowledge, this is the first study to longitudinally examine both grey matter volume and metabolic alteration patterns in patients with amyotrophic lateral sclerosis, over a mean follow-up time of 1 year. We identify how changes of the inferior frontal gyrus critically underly later cognitive performance, shedding new light on its high prognostic significance for amyotrophic lateral sclerosis-related changes. These results have important implications for our understanding of structural and functional changes associated with amyotrophic lateral sclerosis and how they underly cognitive impairments.

EEG resting-state functional connectivity: evidence for an imbalance of external/internal information integration in autism.

BACKGROUND: Autism spectrum disorder (ASD) is associated with atypical neural activity in resting state. Most of the studies have focused on abnormalities in alpha frequency as a marker of ASD dysfunctions. However, few have explored alpha synchronization within a specific interest in resting-state networks, namely the default mode network (DMN), the sensorimotor network (SMN), and the dorsal attention network (DAN). These functional connectivity analyses provide relevant insight into the neurophysiological correlates of multimodal integration in ASD. METHODS: Using high temporal resolution EEG, the present study investigates the functional connectivity in the alpha band within and between the DMN, SMN, and the DAN. We examined eyes-closed EEG alpha lagged phase synchronization, using standardized low-resolution brain electromagnetic tomography (sLORETA) in 29 participants with ASD and 38 developing (TD) controls (age, sex, and IQ matched). RESULTS: We observed reduced functional connectivity in the ASD group relative to TD controls, within and between the DMN, the SMN, and the DAN. We identified three hubs of dysconnectivity in ASD: the posterior cingulate cortex, the precuneus, and the medial frontal gyrus. These three regions also presented decreased current source density in the alpha band. CONCLUSION: These results shed light on possible multimodal integration impairments affecting the communication between bottom-up and top-down information. The observed hypoconnectivity between the DMN, SMN, and DAN could also be related to difficulties in switching between externally oriented attention and internally oriented thoughts.

Avoidance behaviour generalizes to eye processing in posttraumatic stress disorder.

Background: Avoidance describes any action designed to prevent an uncomfortable situation or emotion from occurring. Although it is a common reaction to trauma, avoidance becomes problematic when it is the primary coping strategy, and plays a major role in the development and maintenance of posttraumatic stress disorder (PTSD). Avoidance in PTSD may generalize to non-harmful environmental cues that are perceived to be unsafe. Objective: We tested whether avoidance extends to social cues (i.e. emotional gazes) that are unrelated to trauma. Method: A total of 159 participants (103 who had been exposed to the 2015 Paris terrorist attacks and 56 who had not) performed a gaze-cueing task featuring sad, happy and neutral faces. Attention to the eye area was recorded using an eyetracker. Of the exposed participants, 52 had been diagnosed with PTSD (PTSD+) and 51 had not developed PTSD (PTSD-). As a result of the preprocessing stages, 52 PTSD+ (29 women), 50 PTSD- (20 women) and 53 nonexposed (31 women) participants were included in the final analyses. Results: PTSD+ participants looked at sad eyes for significantly less time than PTSD- and nonexposed individuals. This effect was negatively correlated with the intensity of avoidance symptoms. No difference was found for neutral and happy faces. Conclusions: These findings suggest that maladaptive avoidance in PTSD extends to social processing, in terms of eye contact and others' emotions that are unrelated to trauma. New therapeutic directions could include targeting sociocognitive deficits. Our findings open up new and indirect avenues for overcoming maladaptive avoidance behaviours by remediating eye processing.Trial registration: ClinicalTrials.gov identifier: NCT02810197. HIGHLIGHTS: Avoidance is a key symptom of posttraumatic stress disorder (PTSD).Avoidance is often viewed as limited to reminders linked to the trauma.Results show that attention to the eyes of sad faces is also affected by PTSD. This effect is correlated with avoidance symptoms in PTSD.

Antecedentes: La evitación describe cualquier acción diseñada para prevenir una situación o emoción desagradable. Aunque es una reacción común al trauma, la evitación se vuelve problemática cuando es la principal estrategia de afrontamiento, y desempeña un papel importante en el desarrollo y mantenimiento del trastorno de estrés postraumático (TEPT). La evitación en el TEPT puede generalizarse a señales ambientales no dañinas que se perciben como inseguras. Objetivo: Probamos si la evitación se extiende a las señales sociales (es decir, las miradas emocionales) que no están relacionadas con el trauma. Método: Un total de 159 participantes (103 que habían estado expuestos a los atentados terroristas de París del 2015 y 56 que no lo habían estado) realizaron una tarea de captación de miradas con rostros tristes, felices y neutros. La atención a la zona de los ojos se registró mediante un rastreador ocular. De los participantes expuestos, 52 habían sido diagnosticados con TEPT (TEPT+) y 51 no habían desarrollado TEPT (TEPT-). Resultados: Los participantes con TEPT+ miraron los ojos tristes durante un tiempo significativamente menor que los individuos con TEPT- y los no expuestos. Este efecto se correlacionó negativamente con la intensidad de los síntomas de evitación. No se encontraron diferencias para las caras neutras y felices Conclusiones: Estos hallazgos sugieren que la evitación desadaptativa en el TEPT se extiende al procesamiento social, en cuanto al contacto visual y las emociones de los demás que no están relacionadas con el trauma. Las nuevas direcciones terapéuticas podrían incluir centrarse en los déficits sociocognitivos. Nuestros hallazgos abren vías nuevas e indirectas para superar las conductas de evitación desadaptativas mediante la remediación del procesamiento ocular.

Longitudinal Study of Cognitive and Emotional Alterations in Amyotrophic Lateral Sclerosis: Clinical and Imaging Data.

Objectives: Extra-motor manifestations occur in 50% of patients with amyotrophic lateral sclerosis (ALS). These mainly concern cognition, emotional processing and behavior. Depression and anxiety are less frequent. Little is known about how these manifestations change as the disease progresses. Similarly, although cortical thinning has been well-documented at disease onset, there are scant data about cortical thinning over time and how this correlates with extra-motor manifestations. The present study therefore assessed cognitive, emotional and psychological state and cortical thinning in a group of patients with ALS at baseline and after a follow-up period. Methods: We assessed executive functions, facial emotion recognition, depressive and anxious symptoms, and cortical thinning in 43 patients with ALS at baseline, comparing them with 28 healthy controls, and 21 of them 9 months later. We looked for links among the extra-motor manifestations and correlations with cortical thickness. Results: At baseline, patients had poor executive function and recognition of complex emotions from the eyes, and more anxious and depressive symptoms than controls. At follow-up, only inhibition abilities had worsened. Cortical thinning was observed in bilateral pre-central regions and other parts of the cerebral cortex at baseline. Over time, it worsened in motor and extra-motor areas. Executive functions correlated with thinning in the middle and inferior frontal gyrus and orbitofrontal cortex. Conclusions: During follow-up, there was little deterioration in extra-motor manifestations and psychological state, despite continuing cortical thinning. Patients with affective Theory of Mind (ToM) changes seemed less depressed than the others. Impaired mental flexibility was subtended by prefrontal regions with cortical thinning.

Exploring the Event-Related Potentials' Time Course of Associative Recognition in Autism.

Behavioral data on episodic recollection in autism spectrum disorders (ASD) point limited relational memory functioning. However, the involvement of successive memory processes in the profile of episodic memory in ASD needs more study. Here, we used event-related potentials (ERP) to investigate the time course of episodic recollection with an associative recognition paradigm with picture pairs. Twenty-two participants with ASD and 32 with typical development (TD), all right-handed, were included. Behavioral results confirmed difficulties in correctly recognizing identical pairs in the ASD relative to TD group. We found an unexpected amplitude decrement on the P2 (220-270 msec) and FN400 (350-470 msec) potentials, suggesting diminished priming and familiarity effects in the ASD relative to TD group. However, ERP data revealed that the recognition of associative information relies on the same electrophysiological process (old/new effect in the 600-700-msec late positive component) in ASD participants as in TD ones, with a parietal extension in the ASD group. These results suggest that the electrophysiological processes of associative recognition are qualitatively similar in individuals with and without ASD but may differ quantitatively. This difference may be driven by the reduced early processing of picture pairs that may in turn lead to their diminished integration into the semantic memory system, being partially compensated by a greater involvement of associative memory during the recollection process. Other studies would be useful to go further in identifying these cognitive processes involved in atypical recognition in ASD and their neural substrates. Autism Res 2020, 13: 1998-2016. © 2020 International Society for Autism Research and Wiley Periodicals LLC LAY SUMMARY: We identified diminished performance on the associative recognition of picture pairs in adolescents and young adults with autism when compared to typical development. Electrophysiological data revealed qualitative similarities but quantitative differences between-group, with diminished priming and familiarity processes partially compensated by an enhanced parietal recollection process.

Long-term modulation of cardiac activity induced by inhibitory control over emotional memories.

Efforts to exclude past experiences from conscious awareness can lead to forgetting. Memory suppression is central to affective disorders, but we still do not really know whether emotions, including their physiological causes, are also impacted by this process in normal functioning individuals. In two studies, we measured the after-effects of suppressing negative memories on cardiac response in healthy participants. Results of Study 1 revealed that efficient control of memories was associated with long-term inhibition of the cardiac deceleration that is normally induced by disgusting stimuli. Attempts to suppress sad memories, by contrast, aggravated the cardiac response, an effect that was closely related to the inability to forget this specific material. In Study 2, electroencephalography revealed a reduction in power in the theta (3-8 Hz), alpha (8-12 Hz) and low-beta (13-20 Hz) bands during the suppression of unwanted memories, compared with their voluntary recall. Interestingly, however, the reduction of power in the theta frequency band during memory control was related to a subsequent inhibition of the cardiac response. These results provide a neurophysiological basis for the influence of memory control mechanisms on the cardiac system, opening up new avenues and questions for treating intrusive memories using motivated forgetting.

Alexithymia in Amyotrophic Lateral Sclerosis and Its Neural Correlates.

Introduction: Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease that causes progressive and extensive motor deficits. Patients may also have cognitive impairments or alteration of emotional processing. Very few studies, however, have looked at deficits in how they experience their own feelings (alexithymia). Methods: We assessed alexithymia in 28 patients with ALS using the 20-item Toronto Alexithymia Scale (TAS-20), comparing them with a control group matched for sex, age, and education level. We took into account both the total score of the TAS-20 and its three subscores corresponding to the three dimensions of alexithymia: Difficulty Identifying Feelings (DIF), Difficulty Describing Feelings (DDF), and Externally Oriented Thinking (EOT). Patients also underwent a neuropsychological assessment and anatomical magnetic resonance imaging (MRI) in order to correlate cognitive performances and gray matter volume and level of alexithymia. Results: On average, ALS subjects had a significantly higher total score and DIF sub-score of the TAS-20 than controls indicating an increased alexithymia in patients. Total and DIF Scores correlated significantly and negatively to gray matter volume of the prefrontal cortex, right superior temporal pole and parahippocampal gyri. No correlations were found between scores on executive functions and those on the TAS-20. Conclusion: The first stage of one's own emotional processing seems to be affected in ALS independently of executive dysfunction. This trouble seems to be underpinned by cerebral regions that are well known to be both implicated in alexithymia in healthy subjects and altered in ALS.

Impact of Semantic Relatedness on Associative Memory: An ERP Study.

Encoding and retrieval processes in memory for pairs of pictures are thought to be influenced by inter-item similarity and by features of individual items. Using Event-Related Potentials (ERP), we aimed to identify how these processes impact on both the early mid-frontal FN400 and the Late Positive Component (LPC) potentials during associative retrieval of pictures. Twenty young adults undertook a sham task, using an incidental encoding of semantically related and unrelated pairs of drawings. At test, we conducted a recognition task in which participants were asked to identify target identical pairs of pictures, which could be semantically related or unrelated, among new and rearranged pairs. We observed semantic (related and unrelated pairs) and condition effects (old, rearranged and new pairs) on the early mid-frontal potential. First, a lower amplitude was shown for identical and rearranged semantically related pairs, which might reflect a retrieval process driven by semantic cues. Second, among semantically unrelated pairs, we found a larger negativity for identical pairs, compared to rearranged and new ones, suggesting additional retrieval processing that focuses on associative information. We also observed an LPC old/new effect with a mid-parietal and a right occipito-parietal topography for semantically related and unrelated old pairs, demonstrating a recollection phenomenon irrespective of the degree of association. These findings suggest that associative recognition using visual stimuli begins at early stages of retrieval, and differs according to the degree of semantic relatedness among items. However, either strategy may ultimately lead to recollection processes.

How aging affects sleep-dependent memory consolidation?

Memories are not stored as they were initially encoded but rather undergo a gradual reorganization process, termed memory consolidation. Numerous data indicate that sleep plays a major role in this process, notably due to the specific neurochemical environment and the electrophysiological activity observed during the night. Two putative, probably not exclusive, models ("hippocampo-neocortical dialogue" and "synaptic homeostasis hypothesis") have been proposed to explain the beneficial effect of sleep on memory processes. However, all data gathered until now emerged from studies conducted in young subjects. The investigation of the relationships between sleep and memory in older adults has sparked off little interest until recently. Though, aging is characterized by memory impairment, changes in sleep architecture, as well as brain and neurochemical alterations. All these elements suggest that sleep-dependent memory consolidation may be impaired or occurs differently in older adults. This review outlines the mechanisms governing sleep-dependent memory consolidation, and the crucial points of this complex process that may dysfunction and result in impaired memory consolidation in aging.