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.

Functional connectivity correlates of attentional networks in insomnia disorder: A pilot study.

Insomnia disorder has been associated with poor executive functioning. Functional imaging studies of executive functioning in insomnia are scarce and inconclusive. Because the Attentional Network Test relies on well-defined cortical networks and sensitively distinguishes different aspects of executive function, it might reveal brain functional alterations in relatively small samples of patients. The current pilot study assessed functional connectivity during the Attentional Network Test performed using magnetic resonance imaging in 12 participants with insomnia and 13 self-defined good sleepers. ANCOVAs were used to evaluate group differences in performance and functional connectivity in the regions of interest representing the attentional networks (i.e. alerting, orienting and executive control) at p < 0.05, uncorrected. During the orienting part, participants with insomnia showed weaker connectivity of the precentral gyrus with the superior parietal lobe (false discovery rate-corrected), while they showed stronger connectivity between premotor and visual regions. Individual differences in connectivity between premotor and visual regions correlated inversely with reaction time. Reaction times suggested more efficient executive control in participants with insomnia compared with good sleepers. During the executive control part, participants with insomnia showed stronger connectivity of thalamic parts of the arousal circuit with the middle frontal and the occipital gyri. Conversely, connectivity between the inferior and superior frontal gyri was weaker. Participants with insomnia seem to recruit more cortical resources in visuo-motor regions to orient attention than good sleepers do, and seem to have enhanced executive control that relates to stronger connectivity of arousal-related thalamic areas. This latter result should be treated with caution and requires confirmation.

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.

Are Sleep Complaints Related to Cognitive Functioning in Non-Central Nervous System Cancer? A Systematic Review.

Patients with non-central nervous system (CNS) cancer frequently report cognitive complaints, that are recurrent and affect their quality of life. In order to improve supportive care of these cognitive difficulties, it is important to identify associated factors. Sleep disturbance is a good candidate to study, as patients with non-CNS cancer frequently report sleep disorders, and sleep plays a key role in cognitive functioning. The objective of the present systematic review was to summarize the results of studies evaluating the relationship between cognition and sleep in non-CNS cancer, and to highlight the need for further studies. PubMed [Medline] and Scopus databases were screened from April to November 2020 for studies published in English evaluating the association between cognition and sleep in adults with non-CNS cancer. The characteristics and risk of bias for each of the 30 included studies have been reported. Greater cognitive complaints in patients with non-CNS cancer were related to poorer self-reported sleep quality in almost all studies (n = 22/24). By contrast, around half of the studies reported a significant association between poorer neuropsychological performances and sleep complaints (n = 5/11). The studies were found to have several limitations, such as the lack of a control group, which would have shed the light on the period of occurrence of this association (e.g. after cancer diagnosis or after cancer treatments). Our review also identified factors that may influence the relationship between cognition and sleep. Recommendations are given for improving the methodology of future studies and extending the impact of their results.

Reduced dynamic functional connectivity between salience and executive brain networks in insomnia disorder.

Research into insomnia disorder has pointed to large-scale brain network dysfunctions. Dynamic functional connectivity is instrumental to cognitive functions but has not been investigated in insomnia disorder. This study assessed between-network functional connectivity strength and variability in patients with insomnia disorder as compared with matched controls without sleep complaints. Twelve-minute resting-state functional magnetic resonance images and T1-weighed images were acquired in 65 people diagnosed with insomnia disorder (21-69 years, 48 female) and 65 matched controls without sleep complaints (22-70 years, 42 female). Pairwise correlations between the activity time series of 14 resting-state networks and temporal variability of the correlations were compared between cases and controls. After false discovery rate correction for multiple comparisons, people with insomnia disorder and controls did not differ significantly in terms of mean between-network functional connectivity strength; people with insomnia disorder did, however, show less functional connectivity variability between the anterior salience network and the left executive-control network. The finding suggests less flexible interactions between the networks during the resting state in people with insomnia disorder.

Increased hippocampal-prefrontal functional connectivity in insomnia.

Insomnia Disorder (ID) is the second-most common mental disorder and has a far-reaching impact on daytime functioning. A meta-analysis indicates that, of all cognitive domains, declarative memory involving the hippocampus is most affected in insomnia. Hippocampal functioning has consistently been shown to be sensitive to experimental sleep deprivation. Insomnia however differs from sleep deprivation in many aspects, and findings on hippocampal structure and function have been equivocal. The present study used both structural and resting-state functional Magnetic Resonance Imaging in a larger sample than previously reported to evaluate hippocampal volume and functional connectivity in ID. Included were 65 ID patients (mean age = 48.3 y ±â€¯14.0, 17 males) and 65 good sleepers (mean age = 44.1 y ±â€¯15.2, 23 males). Insomnia severity was assessed with the Insomnia Severity Index (ISI), subjective sleep with the Consensus Sleep Diary (CSD) and objective sleep by two nights of polysomnography (PSG). Seed-based analysis showed a significantly stronger connectivity of the bilateral hippocampus with the left middle frontal gyrus in ID than in controls (p = .035, cluster based correction for multiple comparisons). Further analyses across all participants moreover showed that individual differences in the strength of this connectivity were associated with insomnia severity (ISI, r = 0.371, p = 9.3e-5) and with subjective sleep quality (CSD sleep efficiency, r = -0.307, p = .009) (all p FDR-corrected). Hippocampal volume did not differ between ID and controls. The findings indicate more severe insomnia and worse sleep quality in people with a stronger functional connectivity between the bilateral hippocampus and the left middle frontal gyrus, part of a circuit that characteristically activates with maladaptive rumination and deactivates with sleep.

Primary insomnia patients' performances during simulated car following and urban driving in the afternoon.

According to epidemiological studies, insomnia is associated with an increase in risk of traffic accidents. Recent investigations revealed that patients with insomnia had driving performance impairment under monotonous conditions. However, it is unclear whether other driving abilities may be impacted by insomnia, especially those needing more attentional resources than those involved in monotonous driving. Other findings revealed that impaired performances are more likely to occur with the increase of cognitive demands. However, such tests did not reflect difficulties in situations of everyday life expressed by patients with insomnia, such as driving in an urban environment with traffic and critical situations. Therefore, behaviour in situations encountered in everyday life has to be explored. The aim of the present study was to assess driving performances of patients with insomnia in daily routine tasks such as urban and car-following tests. For this purpose, 15 patients with insomnia and 16 good sleepers performed an urban test of driving with original risk scenarios and a car-following test during the middle afternoon. No significant behavioural difference between patients with insomnia and good sleepers has been found in both the urban test and the car-following test, showing that patients with insomnia have no impairment in behaviour implicated in daily contexts driving tasks of short period of time performed in the late afternoon. Although our results provide a first step towards knowledge of behavioural performance during daily routine driving tasks in patients with insomnia, future studies are needed using on-the-road driving tests and/or different population of patients with insomnia before generalisation.

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.

Facilitation of cutaneous inputs during the planning phase of gait initiation.

It has been shown that during the planning of a voluntary movement the transmission of cutaneous afferent inputs to the somatosensory cortex is attenuated shortly before the motor output as well as during movement execution. However, it is not known whether the sensory suppression observed during the planning phase (i.e., before any movement execution) is a systemic phenomenon or whether it is dependent on movement context. For example, movements such as step initiation are controlled based on information received from cutaneous receptors in the feet. Because afferent information emerging from these receptors is critical for movement initiation, we hypothesized that suppression of these inputs may not occur during the planning phase prior to gait initiation. To examine this hypothesis we measured the cortical response to somatosensory stimulation during the planning phase of step initiation and during movement execution. Sensitivity to cutaneous stimulation was assessed by measuring the amplitude of the cortical somatosensory-evoked potential (SEP, over the Cz electrode) following electrical stimulations of the plantar sole of one foot. Two stimulations were provided during the planning phase of a step movement and two stimulations during movement execution. It was found that the P50-N80 SEP was facilitated in the early planning phase (-700 ms before motor execution) compared with when participants remained still (control standing task). This mechanism might contribute to an enhanced perception of cutaneous input leading to a more accurate setting of the forces to be exerted onto the ground to shift the body's weight toward the supporting side prior to foot-off.

Effects of acute bouts of evening resistance or endurance exercises on sleep EEG and salivary cortisol.

Introduction: Deleterious effects of exercise close to bedtime could be due to increased physiological arousal that can be detected during sleep using sleep spectral analysis. Resistance and endurance exercises have different effects on cortisol release that may lead them to impact sleep spectral signatures differently. The present study aimed to investigate the effects of two types of evening exercise on sleep architecture, sleep spectral parameters and salivary cortisol. Methods: Young healthy participants came to our laboratory to undergo 3 counterbalanced pre-sleep conditions that started 1 h before bedtime (a resistance and an endurance exercise conditions of 30 min duration, identical in terms of workload; and a control condition) followed by polysomnographic recordings. Results were compared between the three conditions for 16 participants. Results: Sleep efficiency was lower after both endurance and resistance exercise than after the control condition. Total sleep time was lower after endurance exercise compared to the control condition. Sleep spectral analyses showed that both endurance and resistance exercises led to greater alpha power during N1 sleep stage and greater theta power during N2 sleep stage compared to the control condition. The endurance exercise led to greater beta power during N2 sleep stage, greater alpha power during REM sleep, and higher cortisol levels compared to the control condition (trend), and compared to the resistance exercise condition (significant). The resistance exercise led to lower beta power during N2 sleep stage than the control condition and lower cortisol levels than the endurance exercise condition. Discussion: This study underlines significant modifications of sleep quality and quantity after both moderate evening endurance and resistance exercises. Still, these effects cannot be considered as deleterious. In contrast to the resistance exercise, endurance exercise led to an increase in sleep EEG activity associated with hyperarousal during sleep and higher cortisol levels, suggesting an hyperarousal effect of endurance exercise performed in the evening. These results align with previous warning about the arousal effects of evening exercise but do not support the notion of deleterious effects on sleep. While these results provide support for the physiological effects of evening exercises on sleep, replication with larger sample size is needed.

Cortical facilitation of proprioceptive inputs related to gravitational balance constraints during step preparation.

Several studies have shown that the transmission of afferent inputs from the periphery to the somatosensory cortex is attenuated during the preparation of voluntary movements. In the present study, we tested whether sensory attenuation is also observed during the preparation of a voluntary step. It would appear dysfunctional to suppress somatosensory information, which is considered to be of the utmost importance for gait preparation. In this context, we predict that the somatosensory information is facilitated during gait preparation. To test this prediction, we recorded cortical somatosensory potentials (SEPs) evoked by bilateral lower limb vibration (i.e., proprioceptive inputs) during the preparation phase of a voluntary right-foot stepping movement (i.e., stepping condition). The subjects were also asked to remain still during and after the vibration as a control condition (i.e., static condition). The amplitude and timing of the early arrival of afferent inflow to the somatosensory cortices (i.e., P1-N1) were not significantly different between the static and stepping conditions. However, a large sustained negativity (i.e., late SEP) developed after the P1-N1 component, which was larger when subjects were preparing a step compared with standing. To determine whether this facilitation of proprioceptive inputs was related to gravitational equilibrium constraints, we performed the same experiment in microgravity. In the absence of equilibrium constraints, both the P1-N1 and late SEPs did not significantly differ between the static and stepping conditions. These observations provide neurophysiological evidence that the brain exerts a dynamic control over the transmission of the afferent signal according to their current relevance during movement preparation.

Tackling Insomnia Symptoms through Vestibular Stimulation in Patients with Breast Cancer: A Perspective Paper.

Insomnia symptoms are common among patients with breast cancer (BC; 20-70%) and are predictors of cancer progression and quality of life. Studies have highlighted sleep structure modifications, including increased awakenings and reduced sleep efficiency and total sleep time. Such modifications may result from circadian rhythm alterations consistently reported in this pathology and known as carcinogenic factors, including lower melatonin levels, a flattened diurnal cortisol pattern, and lower rest-activity rhythm amplitude and robustness. Cognitive behavioral therapy and physical activity are the most commonly used non-pharmacological interventions to counter insomnia difficulties in patients with BC. However, their effects on sleep structure remain unclear. Moreover, such approaches may be difficult to implement shortly after chemotherapy. Innovatively, vestibular stimulation would be particularly suited to tackling insomnia symptoms. Indeed, recent reports have shown that vestibular stimulation could resynchronize circadian rhythms and improve deep sleep in healthy volunteers. Moreover, vestibular dysfunction has been reported following chemotherapy. This perspective paper aims to support the evidence of using galvanic vestibular stimulation to resynchronize circadian rhythms and reduce insomnia symptoms in patients with BC, with beneficial effects on quality of life and, potentially, survival.

Functional connectivity of the medial prefrontal cortex related to mindreading abilities.

The medial prefrontal cortex is a key region of mindreading belonging to the mentalizing system, a set of brain areas underlying mental state inference based on reasoning on social concepts. The aim of this study was to characterize the functional connectivity between regions involved in mindreading and to highlight the processes it underpins, focusing on the dorsal and ventral parts of the medial prefrontal cortex. We analyzed resting-state functional magnetic resonance imaging of 56 healthy volunteers, to study the relationship between mindreading abilities and functional connectivity of the medial prefrontal cortex. Cognitive mindreading performances were correlated with connectivity between the medial prefrontal cortex and frontal regions involved in the regulation of the salience of one's own mental contents, with a distinction between the dorsal part connected to regions subtending inhibition processes and the ventral part to emotional regions. Affective mindreading performances were negatively correlated with negative connectivity of the ventro- and dorsomedial prefrontal cortex with sensorimotor regions belonging to the mirror neuron system subtending the simulation of mental states. These findings suggested a role of the medial prefrontal cortex to decrease the salience of one's own mental content and in the antisynchronous interaction between the mentalizing and mirror neurons systems.

Rest activity rhythms characteristics of breast cancer women following endocrine therapy.

Rest-activity rhythm (RAR) disruptions are frequently associated with chemotherapy in breast cancer (BC), but they are less known in BC with endocrine therapy (ET). The aim of this ancillary study was to characterize the RAR and estimated sleep characteristics from actigraphy in BC patients either treated (ET+) or untreated with ET (ET-), compared to healthy controls (HC) and using a cross-sectional design. Eighteen ET+, 18 ET-, and 16 HC completed questionnaires and wore wrist actigraphs at home for 2 weeks. Parametric and nonparametric RAR, sleep parameters, and quality of life were compared between groups (p < .05). BC groups presented lower daytime activity than HC according to RAR analysis (mesor and M10 parameters). Compared to HC, ET- had lower inter-daily stability and ET+ had greater sleep complaints. Compared to ET-, ET+ had lower sleep efficiency, more time awake, and higher activity levels at night, as assessed with actigraphy. Our results suggest an effect of cancer independent of treatment on RAR in BC, highlighting the need for further investigation of this topic. In contrast, sleep as assessed with actigraphy seems modified only during ET which matches with patients' sleep complaints. Further longitudinal studies would aid in confirming the latter hypothesis.

Sleep-dependent memory consolidation in breast cancer: Use of a virtual reality prospective memory task.

Background: Previous studies have revealed both sleep alterations and prospective memory (PM) impairments in breast cancer (BC) patients. PM refers to memory of intended actions and is crucial for daily living tasks and treatment compliance. As sleep is known to favor memory consolidation, one may expect that changes in sleep quality related to BC would have an impact on PM performance. This study aimed at assessing sleep-dependent consolidation of intentions using an ecological, virtual reality-based PM task in BC patients not treated with chemotherapy. Materials and methods: Thirty-seven early stages BC patients and 21 healthy controls (HC) participated in this study. PM was assessed using a virtual reality task, during which participants learnt a list of intentions and recalled them after a retention interval filled with a day awake or a night of sleep monitored by polysomnography. Sleep spindles and slow waves, brain oscillations involved in sleep-dependent memory consolidation, were quantified automatically using the Aseega software (Physip). Subjective sleep disturbances and markers of quality of life (psychological distress, fatigue, and well-being) were assessed by questionnaires. Results: Greater PM performance was observed after sleep than after an equivalent period of daytime wakefulness for both groups (HC and BC). PM performance after sleep did not differ significantly between groups. Yet, BC patients reported greater sleep disturbances than HC which were related with poorer intentions retrieval, greater psychological distress, fatigue and poorer well-being. The frequency of spindles was higher and the amplitude of slow waves lower in BC patients compared to HC. However, no significant association was observed between polysomnography parameters and PM scores in the whole sample of participants. Conclusion: Although subtle changes in brain oscillations involved in sleep-dependent memory consolidation were observed, these changes did not significantly impair overnight PM consolidation in BC patients. Nevertheless, poorer PM performance was associated with greater sleep complaints which in turn were related to poorer quality of life. Overall, these data suggest that sleep-dependent PM consolidation mechanisms are not altered in early stages BC patients not treated with chemotherapy. Further investigations are needed to understand the association between markers of quality of life and sleep-dependent memory consolidation.

Cancer-related cognitive impairment in non-CNS cancer patients: Targeted review and future action plans in Europe.

Cancer-related cognitive impairment (CRCI) has increasingly been identified over the last two decades in non-CNS system cancer patients. Across Europe, researchers have contributed to this effort by developing preclinical models, exploring underlying mechanisms and assessing cognitive and quality of life changes. The ultimate goal is to develop interventions to treat patients experiencing CRCI. To do so, new challenges need to be addressed requiring the implementation of multidisciplinary research groups. In this consensus paper, we summarize the state of the art in the field of CRCI combined with the future challenges and action plans in Europe. These challenges include data sharing/pooling, standardization of assessments as well as assessing additional biomarkers and neuroimaging investigations, notably through translational studies. We conclude this position paper with specific actions for Europe based on shared scientific expert opinion and stakeholders involved in the Innovative Partnership for Action Against Cancer, with a particular focus on cognitive intervention programs.

Longitudinal investigation of cognitive deficits in breast cancer patients and their gray matter correlates: impact of education level.

Cognitive deficits are a major complaint in breast cancer patients, even before chemotherapy. Comprehension of the cerebral mechanisms related to cognitive impairment in breast cancer patients remains difficult due to the scarcity of studies investigating both cognitive and anatomical imaging changes. Furthermore, only some of the patients experienced cognitive decline following chemotherapy, yet few studies have identified risk factors for cognitive deficits in these patients. It has been shown that education level could impact cognitive abilities during the recovery phase following chemotherapy. Our main aim was to longitudinally evaluate cognitive and anatomical changes associated with cancer and chemotherapy in breast cancer patients. Our secondary aim was to assess the impact of education level on cognitive performances and gray matter (GM) atrophy in these patients. Twenty patients were included before chemotherapy (T1), 1 month (T2) and 1 year (T3) after chemotherapy. Twenty-seven controls without a history of cancer were assessed at T1 and T3 only. Cluster groups based on education level were defined for both groups and were further compared. Comparison between patients and controls revealed deficits in patients on verbal episodic memory retrieval at T1 and T3 and on executive functions at T3. After chemotherapy, breast cancer patients had GM atrophy that persisted or recovered 1 year after chemotherapy depending on the cortical areas. Increase in GM volumes from T1 to T3 were also found in both groups. At T2, patients with a higher level of education compared to lower level exhibited higher episodic memory retrieval and state anxiety scores, both correlating with cerebellar volume. This higher level of education group exhibited hippocampal atrophy. Our results suggest that, before chemotherapy, cancer-related processes impact cognitive functioning and that this impact seems exacerbated by the effect of chemotherapy on certain brain regions. Increase in GM volumes after chemotherapy were unexpected and warrant further investigations. Higher education level was associated, 1 month after the end of chemotherapy, with greater anxiety and hippocampal atrophy despite a lack of cognitive deficits. These results suggest, for the first time, the occurrence of compensation mechanisms that may be linked to cognitive reserve in relationship to state anxiety. This identification of factors, which may compensate cognitive impairment following chemotherapy, is critical for patient care and quality of life.

How to assess and manage cognitive impairment induced by treatments of non-central nervous system cancer.

A number of neurotoxicity associated with oncological treatments has been reported in non-central nervous system cancers. An expert group presents the state of the art and a guide to help the choice of appropriated tools to assess patient cognition in studies on oncology and neurobehavior in animal models. In addition, current cognitive rehabilitation programs currently under evaluation are also discussed. Cognitive assessments in oncology depend on the research question, study design, cognitive domains, patients' characteristics, psychometric properties of the tests, and whether the tests are supervised or not by a neuropsychologist. Batteries of electronic tests can be proposed, but several of them are characterized by weak psychometric developments. In order to improve the comprehension on the impact of cancer treatments on cognition, new animal models are in development, and would in the future include non-human primate models. By bringing together the skills and practices of oncologists, neurologists, neuropsychologists, neuroscientists, we propose a series of specific tools and tests that accompany the cognitive management of non-CNS cancer patients.

Sensitivity and validity of psychometric tests for assessing driving impairment: effects of sleep deprivation.

OBJECTIVE: To assess drug induced driving impairment, initial screening is needed. However, no consensus has been reached about which initial screening tools have to be used. The present study aims to determine the ability of a battery of psychometric tests to detect performance impairing effects of clinically relevant levels of drowsiness as induced by one night of sleep deprivation. METHODS: Twenty four healthy volunteers participated in a 2-period crossover study in which the highway driving test was conducted twice: once after normal sleep and once after one night of sleep deprivation. The psychometric tests were conducted on 4 occasions: once after normal sleep (at 11 am) and three times during a single night of sleep deprivation (at 1 am, 5 am, and 11 am). RESULTS: On-the-road driving performance was significantly impaired after sleep deprivation, as measured by an increase in Standard Deviation of Lateral Position (SDLP) of 3.1 cm compared to performance after a normal night of sleep. At 5 am, performance in most psychometric tests showed significant impairment. As expected, largest effect sizes were found on performance in the Psychomotor Vigilance Test (PVT). Large effects sizes were also found in the Divided Attention Test (DAT), the Attention Network Test (ANT), and the test for Useful Field of View (UFOV) at 5 and 11 am during sleep deprivation. Effects of sleep deprivation on SDLP correlated significantly with performance changes in the PVT and the DAT, but not with performance changes in the UFOV. CONCLUSION: From the psychometric tests used in this study, the PVT and DAT seem most promising for initial evaluation of drug impairment based on sensitivity and correlations with driving impairment. Further studies are needed to assess the sensitivity and validity of these psychometric tests after benchmark sedative drug use.