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A growing body of evidence highlights that the COVID-19 pandemic affected oneiric activity. However, only a few studies have assessed the longitudinal changes in dream phenomenology during different phases of the pandemic, often focused on a limited number of dream variables. The aim of the present study was to provide an exhaustive assessment of dream features during total lockdown (TL) and a post-lockdown (PL) period characterized by eased restrictive measures in Italy. We performed a longitudinal study using a web-based survey to collect demographic, COVID-19 related, clinical, sleep, and dream data at TL and PL. Our final sample included 108 participants. The high frequency of poor sleep quality, anxiety, and depressive symptoms observed during TL remained stable at PL, while sleep latency (t = −4.09; p < 0.001) and PTSD-related disruptive nocturnal behaviors (t = −5.68; p < 0.001) exhibited a reduction at PL. A PL decrease in time spent with digital media was observed (t = −2.77; p = 0.007). We found a strong PL reduction in dream frequency (t = −5.49; p < 0.001), emotional load (t = −2.71; p = 0.008), vividness (t = −4.90; p < 0.001), bizarreness (t = −4.05; p < 0.001), length (t = −4.67; p < 0.001), and lucid dream frequency (t = −2.40; p = 0.018). Fear was the most frequently reported emotion in dreams at TL (26.9%) and PL (22.2%). Only the frequency of specific lockdown-related dream contents exhibited a reduction at PL. These findings highlight that the end of the home confinement had a strong impact on the oneiric activity, in the direction of reduced dream frequency, intensity, and lockdown-related contents. The co-occurrence of such changes with a decline in nocturnal PTSD-related symptoms, sleep latency, and time with digital media suggests an influence of post-traumatic stress levels, lifestyle modifications, and sleep pattern on dream changes during different phases of the pandemic. The stable prevalence of fear in dreams and the large frequency of poor sleep quality, depressive symptoms, and anxiety are probably related to the persistence of many negative consequences of the pandemic. Overall, these results are consistent with the continuity hypothesis of dreams.

In aiming sport contexts, the quiet eye (QE) - the final ocular fixation before movement initiation - is a crucial perceptual-cognitive skill. Indeed, an extended QE permits athletes to achieve high performances, aiding optimal attentional control, particularly in situations in which athletes are "under pressure." Such situations are common in sport, especially when time runs out, and even just a few points can mean the difference between victory and defeat. Although QE has been widely investigated across several sports and tasks, no previous studies have considered both the role of time pressure and performance pressure on QE. The current study aimed to comprehend the effect of tough sport situations on QE characteristics. Accordingly, we tested basketball players (competitive-elites and semi-elites) in free throw trials, manipulating both the time available to perform the task and the relevance of the performance. The results showed that time pressure and performance pressure impaired QE characteristics, regardless of expertise levels. Also, time pressure led to a decrease in free throw accuracy. Interestingly, the match between task demands and the ability to cope seemed to play a role on QE, especially in the competitive-elite players, with negative QE characteristics (short and late) when task demands exceeded the ability to cope. These findings suggest that QE research and QE training protocols should account for time pressure, performance pressure, and the players' perceived ability to cope with the requested task.

Objective The lockdown due to COVID-19 pandemic had a strong impact on daily habits, emotional experience, mental health and sleep. A large body of evidence suggests that dreams are affected by both waking experiences and sleep pattern. In this view, the lockdown should have induced intense modifications in dreaming activity. The aim of the study was to assess dream features during the lockdown in Italy. Methods We used an online survey to collect self-reported demographic, clinical, sleep and dream data. Our sample included 1091 participants. Results Results point to an increased dream frequency, emotional load, vividness, bizarreness and length during the lockdown, compared to a pre-lockdown period. Higher dream frequency and specific qualitative features were found in females and subjects with poor sleep quality, nocturnal disruptive behaviours and depressive symptoms. Most of the dream features assessed during the lockdown were predicted by age, gender, depressive symptoms, presence/absence of other people at home, and territorial area. A specific focus on sleep features revealed that sleep duration and several sleep quality indexes were the best predictors of dream variables. During the lockdown, dreams were also characterized by increased negative emotions, which were particularly frequent in females, younger adults, and participants with poor sleep quality, nocturnal disruptive behaviours, anxiety and depressive symptoms. Conclusions Our results confirm the hypothesis of a strong influence of the pandemic on dreaming, supporting both the hypothesis of continuity between wake and sleep mental processes and the view of a crucial influence of sleep quality and duration on dreaming activity.

Summary Patients with Alzheimer's disease (AD) undergo a slowing of waking electroencephalographic (EEG) rhythms since prodromal stages, which could be ascribed to poor sleep quality. We examined the relationship between wake and sleep alterations by assessing EEG activity during sleep and (pre-sleep/post-sleep) wakefulness in AD, mild cognitive impairment (MCI) and healthy controls. AD and MCI show high sleep latency and less slow-wave sleep. Reduced sigma activity characterizes non-rapid eye movement (NREM) sleep, reflecting sleep spindles loss. The EEG slowing characterizes REM sleep and wakefulness of AD and MCI, with strong correlations among the two phenomena suggesting common neuropathological mechanisms. Evening-to-morning variations in waking EEG revealed the gradual disappearance in MCI and AD of overnight changes in delta activity, indicating a progressive decay of sleep restorative functions on diurnal activity that correlates with the impairment of sleep high-frequency activity in AD. Our findings support a linkage between wake and sleep alterations, and the importance of sleep-related processes in Alzheimer's disease progression., Graphical abstract, Highlights • The EEG slowing characterizes wake and REM sleep in AD and MCI compared to controls • NREM sleep reveals a posterior reduction of sigma EEG power compared to controls • MCI and AD show a progressive decay of sleep restorative functions on diurnal EEG • EEG slowing in REM sleep shows the highest correlation with cognitive impairment, Human Physiology ; Cognitive Neuroscience ; Chronobiology

The multifactorial nature of Alzheimer’s disease (AD) has led scientific researchers to focus on the modifiable and treatable risk factors of AD. Sleep fits into this context, given the bidirectional relationship with AD confirmed by several studies over the last years. Sleep disorders appear at an early stage of AD and continue throughout the entire course of the pathology. Specifically, sleep abnormalities, such as more fragmented sleep, increase in time of awakenings, worsening of sleep quality and primary sleep disorders raise with the severity and progression of AD. Intervening on sleep, therefore, means acting both with prevention strategies in the pre-clinical phase and with treatments during the course of the disease. This review explores sleep disturbances in the different stages of AD, starting from the pre-clinical stage. Particular attention is given to the empirical evidence investigating obstructive sleep apnea (OSA) disorder and the mechanisms overlapping and sharing with AD. Next, we discuss sleep-based intervention strategies in the healthy elderly population, mild cognitive impairment (MCI) and AD patients. We mention interventions related to behavioral strategies, combination therapies, and bright light therapy, leaving extensive space for new and raising evidence on continuous positive air pressure (CPAP) treatment effectiveness. Finally, we clarify the role of NREM sleep across the AD trajectory and consider the most recent studies based on the promising results of NREM sleep enhancement, which use innovative experimental designs and techniques.

Sports practice is not only a way to be in shape or to have fun, but also a tool to inculcate and promote prosocial values. For this reason, the program "L'Eliana: school of values" was designed with the objectives of achieving a quality sports education, promoting the emotional and social development of young people, promote an environment where coexistence and values are integrated into sports practice and educate in the comprehensive global development of athletes as people. The program involved 461 users of the Municipal Sports Schools of l'Eliana, the satisfaction survey gathered a sample of 356 people. The variables collected were reason for practice, value of their sport, presence of value in their training, and importance of work in values. The most chosen practice motives were social and competitive, while fun and improving health or the physical result in lesser results. The results showed that the values are distributed in a balanced way, although cooperation, overcoming and discipline stand out. Most of the sample (81.5%) considers that work in values is very important in sports practice. On the other hand, 49.1% consider that the values are quite or very present in their sports practice. The program 'Sport: School of Values' demonstrated its effectiveness in the process and results evaluations. However, it is necessary to extend the intervention over time and guarantee its application in the daily training systems.

This study tested a simple statistical procedure to recognize single treatment-naïve HIV individuals having abnormal cortical sources of resting state delta (4 Hz) and alpha (8-13 Hz) electroencephalographic (EEG) rhythms with reference to a control group of sex-, age-, and education-matched healthy individuals. Compared to the HIV individuals with a statistically normal EEG marker, those with abnormal values were expected to show worse cognitive status.Resting state eyes-closed EEG data were recorded in 82 treatment-naïve HIV (39.8 ys.±1.2 standard error mean, SE) and 59 age-matched cognitively healthy subjects (39 ys.±2.2 SE). Low-resolution brain electromagnetic tomography (LORETA) estimated delta and alpha sources in frontal, central, temporal, parietal, and occipital cortical regions.Ratio of the activity of parietal delta and high-frequency alpha sources (EEG marker) showed the maximum difference between the healthy and the treatment-naïve HIV group. Z-score of the EEG marker was statistically abnormal in 47.6% of treatment-naïve HIV individuals with reference to the healthy group (p0.05). Compared to the HIV individuals with a statistically normal EEG marker, those with abnormal values exhibited lower mini mental state evaluation (MMSE) score, higher CD4 count, and lower viral load (p0.05).This statistical procedure permitted for the first time to identify single treatment-naïve HIV individuals having abnormal EEG activity.This procedure might enrich the detection and monitoring of effects of HIV on brain function in single treatment-naïve HIV individuals.

The aim of the study was to evaluate the effects of the Quiet eye (QE) phenomenon on performances during the shooting section of "Laser Run" of Modern Pentathlon, in two samples of athletes (novices and experts). The "Laser Run" consists of running and shooting activities. The study involved 18 experienced athletes of the Italian National Team of Modern Pentathlon (i.e., "elite" group) and 18 young and nonexpert athletes of a local Pentathlon club (i.e., "novice" group). Participants performed, in ecological conditions, five trials of four series of shootings (as it occurs in the real competitions), for a total of 20 series. During the shooting trials, athletes wore a mobile Eye Tracking System to record eye movements (saccades, blinks, and fixations). Key measures of the study were QE parameters (QE Duration [QED], Relative QED [RQED], and QE Onset), as well as the performance (accuracy and time to perform the event). The results revealed that both groups of athletes had a longer QED, RQED, and an earlier onset during their best shots than during the worse ones. Furthermore, differences between the groups showed that elite athletes had an earlier onset and a shorter QED than the novice group of athletes. These results provide insightful information about different cognitive and perceptual processes involved in Modern Pentathlon's athletes' performances at both the elite and non-elite level.

The K-complex (KC) is one of the hallmarks of Non-Rapid Eye Movement (NREM) sleep. Recent observations point to a drastic decrease of spontaneous KCs in Alzheimer’s disease (AD). However, no study has investigated when, in the development of AD, this phenomenon starts. The assessment of KC density in mild cognitive impairment (MCI), a clinical condition considered a possible transitional stage between normal cognitive function and probable AD, is still lacking. The aim of the present study was to compare KC density in AD/MCI patients and healthy controls (HCs), also assessing the relationship between KC density and cognitive decline. Twenty amnesic MCI patients underwent a polysomnographic recording of a nocturnal sleep. Their data were compared to those of previously recorded 20 HCs and 20 AD patients. KCs during stage 2 NREM sleep were visually identified and KC densities of the three groups were compared. AD patients showed a significant KC density decrease compared with MCI patients and HCs, while no differences were observed between MCI patients and HCs. KC density was positively correlated with Mini-Mental State Examination (MMSE) scores. Our results point to the existence of an alteration of KC density only in a full-blown phase of AD, which was not observable in the early stage of the pathology (MCI), but linked with cognitive deterioration.

Although a slowing of electroencephalographic (EEG) activity during wakefulness and –to some extent- sleep of Alzheimer disease (AD) patients (i.e., increased slow-frequency activity) was documented, recent findings in healthy elderly show a decreased 0.6–1 Hz slow wave activity (SWA) during NREM, which was associated to β-amyloid deposition and impaired hippocampal memory consolidation. We hypothesize that the apparent contradiction may be explained by the partial overlap between 0.6–1 Hz EEG activity and K-Complex (KC). According to this view, we studied both frontal KCs and SWA in 20 AD patients and 20 healthy age-matched controls (HC) during nightly sleep, under the hypothesis that KCs better discriminate patients from healthy elderly than ≤1 Hz SWA. A drastic decrease of KC density during stage 2 NREM was found in AD compared to HC. Patients show more than 40% reduction of the KC density, allowing a correct classification of 80%. On the other hand, ≤1 Hz SWA of AD patients is slightly (not significantly) higher in most cortical areas compared to HC. Although no significant changes of ≤1 Hz SWA are detectable over frontal areas in AD, KC density decreases over the same location, and its decrease is related to the cognitive decline.

WOS: 000405068100016 PubMed ID: 28454845 The aim of this retrospective exploratory study was that resting state eyes-closed electroencephalographic (rsEEG) rhythms might reflect brain arousal in patients with dementia due to Alzheimer's disease dementia (ADD), Parkinson's disease dementia (PDD), and dementia with Lewy body (DLB). Clinical and rsEEG data of 42 ADD, 42 PDD, 34 DLB, and 40 healthy elderly (Nold) subjects were available in an international archive. Demography, education, and Mini-Mental State Evaluation score were not different between the patient groups. Individual alpha frequency peak (IAF) determined the delta, theta, alpha 1, alpha 2, and alpha 3 frequency bands. Fixed beta 1, beta 2, and gamma bands were also considered. rsEEG cortical sources were estimated by means of the exact low-resolution brain electromagnetic source tomography and were then classified across individuals, on the basis of the receiver operating characteristic curves. Compared to Nold, IAF showed marked slowing in PDD and DLB and moderate slowing in ADD. Furthermore, all patient groups showed lower posterior alpha 2 source activities. This effect was dramatic in ADD, marked in DLB, and moderate in PDD. These groups also showed higher occipital delta source activities, but this effect was dramatic in PDD, marked in DLB, and moderate in ADD. The posterior delta and alpha sources allowed good classification accuracy (approximately 0.85-0.90) between the Nold subjects and patients, and between ADD and PDD patients. In quiet wakefulness, delta and alpha sources unveiled different spatial and frequency features of the cortical neural synchronization underpinning brain arousal in ADD, PDD, and DLB patients. Future prospective cross-validation studies should test these rsEEG markers for clinical applications and drug discovery. project "GRIDCORE" (Italian Ministry of Health, Finalized Research program) [RF-2010-2319113] The present study was developed based on the data of the informal European Consortium PDWAVES. The members and institutional affiliations of the Consortium are reported in the cover page of this manuscript. The activities for this study of Dr. Claudio Babiloni, Claudio Del Percio, and Roberta Lizio performed in the framework of the project "GRIDCORE" (Italian Ministry of Health, Finalized Research program, prot. RF-2010-2319113).

WOS: 000404876400029 PubMed ID: 28621693 The aim of this retrospective and exploratory study was that the cortical sources of resting state eyes-closed electroencephalographic (rsEEG) rhythms might reveal different abnormalities in cortical neural synchronization in groups of patients with mild cognitive impairment due to Alzheimer's disease (ADMCI) and Parkinson's disease (PDMCI) as compared to healthy subjects. Clinical and rsEEG data of 75 ADMCI, 75 PDMCI, and 75 cognitively normal elderly (Nold) subjects were available in an international archive. Age, gender, and education were carefully matched in the three groups. The Mini-Mental State Evaluation (MMSE) was matched between the ADMCI and PDMCI groups. Individual alpha frequency peak (IAF) was used to determine the delta, theta, alpha1, alpha2, and alpha3 frequency band ranges. Fixed beta1, beta2, and gamma bands were also considered. eLORETA estimated the rsEEG cortical sources. Receiver operating characteristic curve (ROC) classified these sources across individuals. Results showed that compared to the Nold group, the posterior alpha2 and alpha3 source activities were more abnormal in the ADMCI than the PDMCI group, while the parietal delta source activities were more abnormal in the PDMCI than the ADMCI group. The parietal delta and alpha sources correlated with MMSE score and correctly classified the Nold and diseased individuals (area under the ROC=0.77-0.79). In conclusion, the PDMCI and ADMCI patients showed different features of cortical neural synchronization at delta and alpha frequencies underpinning brain arousal and vigilance in the quiet wakefulness. Future prospective cross-validation studies will have to test these rsEEG markers for clinical applications and drug discovery. Italian Ministry of Health [RF-2010-2319113] The present study was developed based on the data of the informal European Consortium PDWAVES. The members and institutional affiliations of the Consortium are reported in the cover page of this manuscript. The activities for this study of Dr. Claudio Babiloni, Claudio Del Percio, and Roberta Lizio were performed in the framework of the project "GRIDCORE" (Italian Ministry of Health, Finalized Research program, prot. RF-2010-2319113).

Background In the field of Alzheimer's disease (AD), the validation of biomarkers for early AD diagnosis and for use as a surrogate outcome in AD clinical trials is of considerable research interest. Objective To characterize the clinical profile and genetic, neuroimaging and neurophysiological biomarkers of prodromal AD in amnestic mild cognitive impairment (aMCI) patients enrolled in the IMI WP5 PharmaCog (also referred to as the European ADNI study). Methods A total of 147 aMCI patients were enrolled in 13 European memory clinics. Patients underwent clinical and neuropsychological evaluation, magnetic resonance imaging (MRI), electroencephalography (EEG) and lumbar puncture to assess the levels of amyloid β peptide 1–42 (Aβ42), tau and p‐tau, and blood samples were collected. Genetic (APOE), neuroimaging (3T morphometry and diffusion MRI) and EEG (with resting‐state and auditory oddball event‐related potential (AO‐ERP) paradigm) biomarkers were evaluated. Results Prodromal AD was found in 55 aMCI patients defined by low Aβ42 in the cerebrospinal fluid (Aβ positive). Compared to the aMCI group with high Aβ42 levels (Aβ negative), Aβ positive patients showed poorer visual (P = 0.001), spatial recognition (P < 0.0005) and working (P = 0.024) memory, as well as a higher frequency of APOE4 (P < 0.0005), lower hippocampal volume (P = 0.04), reduced thickness of the parietal cortex (P < 0.009) and structural connectivity of the corpus callosum (P < 0.05), higher amplitude of delta rhythms at rest (P = 0.03) and lower amplitude of posterior cingulate sources of AO‐ERP (P = 0.03). Conclusion These results suggest that, in aMCI patients, prodromal AD is characterized by a distinctive cognitive profile and genetic, neuroimaging and neurophysiological biomarkers. Longitudinal assessment will help to identify the role of these biomarkers in AD progression.

Objective Cortical sources of electroencephalographic (EEG) rhythms were investigated in two sub-populations of naive HIV subjects, grouped based on clinical criteria to receive different combination anti-retroviral therapies (cARTs). These EEG sources were hypothesized to reflect beneficial effects of both regimes. Methods Eyes-closed resting state EEG data were collected in 19 (Group A) and 39 (Group B) naive HIV subjects at baseline (i.e. pre-treatment; T0) and after 5 months of cART (T5). Compared with the Group A, the Group B was characterized by slightly worse serological parameters and higher cardiovascular risk. At T0, mean viral load (VL) and CD4 count were 87,694 copies/ml and 435 cells/μl in the Group A and 187,370 copies/ml and 331 cells/μl in the Group B. The EEG data were also collected in 50 matched control HIV-negative subjects. Cortical EEG sources were assessed by LORETA software. Results Compared to the Control Group, the HIV Groups showed lower alpha (8–12 Hz) source activity at T0 while the Group B also exhibited higher delta source activity. The treatment partially normalized alpha and delta source activity in the Group A and B, respectively, in association with improved VL, CD4, and cognitive functions. Conclusions Different cART regimens induced diverse beneficial effects in delta or alpha source activity in the two naive HIV Groups. Significance These sources might unveil different neurophysiological effects of diverse cART on brain function in naive HIV Groups as a function of clinical status and/or therapeutic compounds.

This article reviews three experiments on event-related potentials (ERPs) testing the hypothesis that primary visual consciousness (stimulus self-report) is related to enhanced cortical neural synchronization as a function of stimulus features. ERP peak latency and sources were compared between “seen” trials” and “not seen” trials, respectively related and unrelated to the primary visual consciousness. Three salient features of visual stimuli were considered (visuospatial, emotional face expression, and written words). Results showed the typical visual ERP components in both “seen” and “not seen” trials. There was no statistical difference in the ERP peak latencies between the “seen” and “not seen” trials, suggesting a similar timing of the cortical neural synchronization regardless the primary visual consciousness. In contrast, ERP sources showed differences between “seen” and “not seen” trials. For the visuospatial stimuli, the primary consciousness was related to higher activity in dorsal occipital and parietal sources at about 400 milliseconds post-stimulus. For the emotional face expressions, there was greater activity in parietal and frontal sources at about 180 milliseconds post-stimulus. For the written letters, there was higher activity in occipital, parietal and temporal sources at about 230 milliseconds post-stimulus. These results hint that primary visual consciousness is associated with an enhanced cortical neural synchronization having entirely different spatiotemporal characteristics as a function of the features of the visual stimuli and, possibly, the relative qualia (i.e. visuospatial, face expression, and words). In this framework, the dorsal visual stream may be synchronized in association with the primary consciousness of visuospatial and emotional face contents. Analogously, both dorsal and ventral visual streams may be synchronized in association with the primary consciousness of linguistic contents. In this line of reasoning, the ensemble of the cortical neural networks underpinning the single visual features would constitute a sort of multi-dimensional palette of colors, shapes, regions of the visual field, movements, emotional face expressions, and words. The synchronization of one or more of these cortical neural networks, each with its peculiar timing, would produce the primary consciousness of one or more of the visual features of the scene.

Here we presented a single electroencephalographic (EEG) marker for a neurophysiological assessment of Alzheimer’s disease (AD) patients already diagnosed by current guidelines. The ability of the EEG marker to classify 127 AD individuals and 121 matched cognitively intact normal elderly (Nold) individuals was tested. Furthermore, its relationship to AD patients’ cognitive status and structural brain integrity was examined. Low-resolution brain electromagnetic tomography (LORETA) freeware estimated cortical sources of resting state eyes-closed EEG rhythms. The EEG marker was defined as the ratio between the activity of parieto-occipital cortical sources of delta (2–4 Hz) and low-frequency alpha (8–10.5 Hz) rhythms. Results showed 77.2% of sensitivity in the recognition of the AD individuals; 65% of specificity in the recognition of the Nold individuals; and 0.75 of area under the receiver-operating characteristic curve. Compared to the AD subgroup with the EEG maker within one standard deviation of the Nold mean (EEG-), the AD subgroup with EEG+ showed lower global cognitive status, as revealed by Mini-Mental State Evaluation score, and more abnormal values of white-matter and cerebrospinal fluid normalized volumes, as revealed by structural magnetic resonance imaging. We posit that cognitive and functional status being equal, AD patients with EEG+ should receive special clinical attention due to a neurophysiological “frailty”. EEG+ label can be also used in clinical trials (i) to form homogeneous groups of AD patients diagnosed by current guidelines and (ii) as end-point to evaluate intervention effects.

Objective Here we tested the effect of combined antiretroviral therapy (cART) on deviant electroencephalographic (EEG) source activity in treatment-naïve HIV individuals. Methods Resting state eyes-closed EEG data were recorded before and after 5 months of cART in 48 male HIV subjects, who were naïve at the study start. The EEG data were also recorded in 59 age- and sex-matched healthy subjects as a control group. Frequency bands of interest included delta, theta, alpha1, alpha2 and alpha3, based on alpha frequency peak specific to each individual. They also included beta1 (13–20 Hz) and beta2 (20–30 Hz). Low-resolution brain electromagnetic tomography (LORETA) estimated EEG cortical source activity in frontal, central, temporal, parietal, and occipital regions. Results Before the therapy, the HIV group showed greater parietal delta source activity and lower spatially diffuse alpha source activity compared to the control group. Thus, the ratio of parietal delta and alpha3 source activity served as an EEG marker. The z-score showed a statistically deviant EEG marker (EEG +) in 50% of the HIV individuals before therapy (p, Highlights • A statistical z-score tested the effect of antiretroviral therapy on resting state EEG sources in naïve HIV individuals. • Many HIV individuals (50%) had abnormal EEG before the therapy, and > 40% showed its normalization after 5 months of cART. • This procedure might monitor effects of cART on brain function in HIV single individuals.

Several studies have identified two types of sleep spindles: fast (13–15 Hz) centroparietal and slow (11–13 Hz) frontal spindles. Alterations in spindle activity have been observed in Alzheimer’s disease (AD) and Mild Cognitive Impairment (MCI). Only few studies have separately assessed fast and slow spindles in these patients showing a reduction of fast spindle count, but the possible local specificity of this phenomenon and its relation to cognitive decline severity are not clear. Moreover, fast and slow spindle density have never been assessed in AD/MCI. We have assessed fast and slow spindles in 15 AD patients, 15 amnesic MCI patients, and 15 healthy elderly controls (HC). Participants underwent baseline polysomnographic recording (19 cortical derivations). Spindles during nonrapid eye movements sleep were automatically detected, and spindle densities of the three groups were compared in the derivations where fast and slow spindles exhibited their maximum expression (parietal and frontal, resp.). AD and MCI patients showed a significant parietal fast spindle density decrease, positively correlated with Minimental State Examination scores. Our results suggest that AD-related changes in spindle density are specific for frequency and location, are related to cognitive decline severity, and may have an early onset in the pathology development.

Alzheimer's disease (AD) is the most common type of neurodegenerative disorder, typically causing dementia along aging. AD is mainly characterized by a pathological extracellular accumulation of amyloid-beta peptides that affects excitatory and inhibitory synaptic transmission, inducing aberrant patterns in neuronal circuits. Growing evidence shows that AD targets cortical neuronal networks related to cognitive functions including episodic memory and visuospatial attention. This is partially reflected by the abnormal mechanisms of cortical neural synchronization and coupling that generate resting state electroencephalographic (EEG) rhythms. The cortical neural synchronization is typically indexed by EEG power density. The EEG coupling between electrode pairs probes functional (inter-relatedness of EEG signals) and effective (casual effect from one over the other electrode) connectivity. The former is typically indexed by synchronization likelihood (linear and nonlinear) or spectral coherence (linear), the latter by granger causality or information theory indexes. Here we reviewed literature concerning EEG studies in condition of resting state in AD and mild cognitive impairment (MCI) subjects as a window on abnormalities of the cortical neural synchronization and functional and effective connectivity. Results showed abnormalities of the EEG power density at specific frequency bands (

Aim In the framework of IMI PharmaCog project (Grant Agreement no. 115009), this study evaluated whether abnormal cortical sources of resting state electroencephalographic (EEG) rhythms are correlated to cerebrospinal fluid (CSF) ® amyloid (A®) level in amnesic Mild Cognitive Impairment (MCI) subjects. Methods Artifact-free resting state eyes-closed EEG rhythms (19 electrodes) were recorded. Individual datasets were divided into those with high CSF A® level (81 A®-negative, CSF A ® > 550 pg / ml ) and those with low CSF A® level (46 A®-positive, CSF A ® 550 pg / ml ). Regional normalized cortical sources of EEG rhythms at frequency bands of interest were estimated by LORETA package. ANOVA compared these sources between the two MCI groups ( p Results Statistical results showed: (1) source pattern Nold p r =−0.26; p =0.003) across all MCI subjects. Conclusions These results suggest a relationship between the brain amyloid charge, as revealed by CSF A® level, and pathological delta cortical sources indicating cortical disconnection in amnesic MCI subjects. EEG delta sources could represent a promising early diagnostic marker of Alzheimer's disease (AD).

Background and aim In the framework of IMI PharmaCog project (Grant Agreement n°115009, www.pharmacog.org ), this study evaluated whether cortical sources of resting state EEG rhythms were related to cerebrospinal fluid A®42 level in amnesic mild cognitive impairment (MCI) subjects and have translational value in mouse model of AD. Methods The research data (including human biological samples) were sourced ethically and used in line with international ethical standards. EEG rhythms were recorded in 127 aMCI subjects. Cortical sources of global delta (2–4 Hz) and low-frequency alpha (8–10.5 Hz) EEG rhythms were estimated by LORETA package. Back translation was tested on on-going EEG rhythms in wild type and transgenic mouse models of AD developing accumulation of A®42 in the brain (i.e. PDAPP, TASTPM). Results and conclusions (1) delta (

Aim In the framework of IMI PharmaCog project (Grant Agreement no. 115009), this study evaluated whether cortical sources of AO-ERPs are related to cerebrospinal fluid (CSF)® amyloid (A®) level in amnesic Mild Cognitive Impairment (MCI) subjects. Methods Artifact-free AO-ERPs (19 electrodes) were recorded in 115 MCI subjects. Individual datasets were divided into those with high CSF A® level (61 A®-negative, CSF A® > 550 pg/ml) and those with low CSF A® level (43 A®-positive, CSF A® Results The ANOVA for the P3a peak illustrate a statistically significant interaction effect (F = 2.87; p = 0.006) between the factors Group and Brodmann Area (BA 10 and 11). The ANOVA for the P3b peak illustrate a statistically significant interaction effect (F = 2.745; p = 0.008) between the factors Group and BA (BA 5,7,23,31). Conclusions The present study provides support to the hypothesis that specific neurophysiological markers may enrich the discrimination of aMCI subjects in an early stage of prodromal Alzheimer’s disease (AD) for early diagnosis and preventive treatments.

Quantitative analysis of EEG during wakefulness in AD/MCI patients shows a slowing of EEG rhytms, in terms of increase of delta activity and decrease of alpha activity. Some studies show differences in AD/MCI patients even in EEG sleep: an increase in stage 1, number and length of intra-night awakenings, a decrease of Slow Wave Sleep (SWS) and REM sleep. Given the strong relation (bidirectional) between EEG sleep and wakefullness rhythms, the objective of the study is to assess EEG topography during sleep (REM and NREM) and wakefulness, and to assess relationship between sleep EEG modifications and subsequent variations in wakefulness EEG. 8 patients AD, 13 MCI and 9 elderly healthy people performed one-night sleep PSG recordings (19 cortical electrods, EOG, EMG) and wakefulness EEG recordings (5 min with eyes open and 5 min with eyes closed). Analyses of EEG topography of wakefulness, REM and NREM sleep suggest significant differences between MCI groups vs. controls within the alpha band, in terms of lower EEG activity within this frequency range in patients in occipital and temporal derivations compared to controls. Although preliminary, data of EEG topography seems showing the same functional variations both in sleep and wakefulness. Hence, the observed slowing may be an electrophysiological evidence of neurodegenerative processes at a cortical level.

A healthy 68-year-old woman presented with 2 years of recurrent episodes of right ptosis, constantly present after waking from sleep (figure 1). Clinical examination, brain MRI, EMG, and polysomnography were unremarkable (figure 2). In particular, there was no cranial nerve impairment. Few cases of idiopathic ptosis on awakening have been described, and they have been attributed to eyelid opening apraxia.1 This disorder needs to be differentiated from myasthenia gravis and other neuromuscular disorders.2 We propose that the term apraxia is not suitable to describe this clinical phenomenon, which could result from an abnormal, transient persistence of focal sleep-related muscular atonia.