Cognitive training modifies frequency EEG bands and neuropsychological measures in Rett syndrome

Repetitive active and passive cognitive stimulations induce EEG changes in patients with Rett syndrome

BACKGROUND

Despite being considered a rare disease, Rett syndrome is a leading cause of profound cognitive impairment in females. This study explores game-based cognitive stimulation to enhance attention during learning tasks, offering an alternative treatment perspective.

METHODS

Fifteen diagnosed Rett syndrome girls participated in four 24-minute sessions, including a 5-minute initial resting state recording. Primary indicators for analysis included relative power and spectral entropy.

RESULTS

Significant findings indicated variations among conditions (resting state, active task, passive task) in response to stimulation. Notably, over four days, evolution occurred, characterized by decreasing delta power and increasing theta and beta power. Topographic maps confirmed these shifts, highlighting affected brain areas. Linear regression emphasized the most significant impact on the first day, with subsequent shifts towards higher frequencies, particularly during the resting state. By the fourth day, resting-state patterns resembled those during cognitive activities.

CONCLUSION

Findings suggest cognitive stimulation induces substantial EEG spectral changes, potentially linked to cognitive enhancements in Rett syndrome. The shift towards higher frequency bands and increased spectral entropy align with enhanced brain activation during cognitive sessions, underscoring the potential of cognitive stimulation therapies and calling for further research to optimize abilities in individuals with Rett syndrome.

IMPACT

Game-based cognitive stimulation induces substantial EEG changes in individuals with Rett syndrome, enhancing cognitive functions, notably attention during learning. This study conducts a distinctive examination, assessing the habituation paradigm through the combination of game-based cognitive stimulation and learning, providing valuable insights into enhancing attention in Rett syndrome. Impacting understanding of cognitive processes in Rett syndrome, this research reveals significant EEG variations during tasks, emphasizing the potential of cognitive stimulation for attention enhancement and the need for further research in tailored interventions.

EEG connectivity patterns in response to gaming and learning-based cognitive stimulations in Rett syndrome

BACKGROUND

Functional connectivity is scarcely studied in Rett syndrome (RTT). Explorations revealed associations between RTT's clinical, genetic profiles, and coherence measures, highlighting an unexplored frontier in understanding RTT's neural mechanisms and cognitive processes.

AIMS

To evaluate the effects of diverse cognitive stimulations-learning-focused versus gaming-oriented-on electroencephalography brain connectivity in RTT. The comparison with resting states aimed to uncover potential biomarkers and insights into the neural processes associated with RTT.

METHODS AND PROCEDURES

The study included 15 girls diagnosed with RTT. Throughout sessions lasting about 25 min, participants alternated between active and passive tasks, using an eyetracker device while their brain activity was recorded with a 20-channel EEG. Results revealed significant alterations during cognitive tasks, notably in delta, alpha and beta bands. Both tasks induced spectral pattern changes and connectivity shifts, hinting at enhanced neural processing. Hemispheric asymmetry decreased during tasks, suggesting more balanced neural processing. Linear and nonlinear connectivity alterations were observed in active tasks compared to resting state, while passive tasks showed no significant changes.

CONCLUSIONS AND IMPLICATIONS

Results underscores the potential of cognitive stimulation for heightened cognitive abilities, promoting enhanced brain connectivity and information flow in Rett syndrome. These findings offer valuable markers for evaluating cognitive interventions and suggest gaming-related activities as effective tools for improving learning outcomes.

Frontal Theta Asymmetry may be a new target for reducing the severity of depression and improving cognitive function in depressed patients

BACKGROUND

The prevalence of depressive disorder is increasing due to a variety of factors, which brings a huge strain on individuals, families and society. This study aims to investigate whether there is Frontal Theta Asymmetry (FTA) in depressed patients, and whether FTAs are related to depression severity and cognitive function changes in depressed patients.

METHODS

Participants who met the inclusion criteria were enrolled in this study. Socio-demographic data of each participant were recorded. Zung's self-rating Depression Scale was used to assess the depression status of participants. P300 was used to evaluate the cognitive function of participants. EEG data from participants were collected by the NeuroScan SynAmps RT EEG system. t-test, Wilcoxon rank-sum test and Chi-square test were used to detect the differences of different variables between the two groups. Multiple linear regression analysis and multiple logistic regression analysis were used to analyze relationships between FTAs in different regions and participants' depression status and cognitive function.

RESULTS

A total of 66 depressed participants and 47 healthy control participants were included in this study. The theta spectral power of the left frontal lobe was slightly stronger than that of the right frontal lobe in the depression group, while the opposite was true in the healthy control group. The FTA in F3/F4 had certain effects on the emergence of depression in participants, the emergence of depression in participants and Changes in cognitive function.

CONCLUSIONS

FTAs are helpful to assess the severity of depression and early identify cognitive impairment in patients with depression.

Remote cognitive training for children with congenital brain malformation or genetic syndrome: a scoping review

Increased attention is arising on the delivery of remote cognitive interventions, which allow performing exercises in everyday settings, favouring rehabilitation continuity. The present study offers an overview of remote cognitive training programs for children with congenital brain malformation or genetic syndrome affecting the central nervous system, included in papers published in the time period 2011-2021. A total of 13 records was found and discussed including efficacy studies, feasibility studies and study protocols. Many studies have focused on a specific diagnosis, such as cerebral palsy, Down Syndrome, Fragile X Syndrome, while no or little evidence has been gathered on more rare diseases or brain malformations. Interventions were found to generate benefits on some cognitive functions, but problems with adherence were highlighted, especially due to excessive cognitive load from the training or clinical comorbidities. Conclusions remain tentative due to heterogeneity in training, study and patients characteristics, and methodological limitations of studies.

Electroencephalographic assessment in patients with Rett syndrome during cognitive stimulation by means of eye tracking technology and alternative and augmentative communication systems

Rett syndrome (RTT) is considered a rare disease despite being the leading genetic disorder to cause severe intellectual disability in women. There is no cure for RTT, so the treatment is symptomatic and supporting, requiring a multidisciplinary approach. Occupational therapy can help girls and their families to improve communication, being one of the main concerns when verbal language and intentional hand movement are impaired or lost. This paper presents a pilot study of cognitive training through the combined use of eye-tracking technology (ETT) and augmentative and alternative communication (AAC) using the Peabody Picture Vocabulary Test (PPVT-IV). The objective was to evaluate brain activation by means of electroencephalography (EEG) during the stimulation of non-verbal communication. EEG data were recorded during an eyes-open resting state (EO-RS) period and during cognitive stimulation via AAC activity. To assess their effect, both signals were compared at the spectral level, focusing on frequency, brain symmetry and connectivity. During the task, a redistribution of power towards fast frequency bands was observed, as well as an improvement in the brain symmetry index (BSI) and functional synchronicity through increased coherence. Therefore, the results of the spectral analysis showed a possible deviation from the pathological pattern, manifesting a positive effect in the use of non-verbal cognitive stimulation activities. In conclusion, it was observed that it is possible to establish a cognitive training system that produces brain activation and favors communication and learning despite intentional language loss.Clinical Relevance- This manifests a method of cognitive training that would induce brain activation in RTT patients with absence of intentional communication. The evaluation system through spectral analysis could complement the standardized protocols to asses communication that are based on verbal and motor production.

Rett Syndrome: A Tale of Altered Genetics, Synaptic Plasticity, and Neurodevelopmental Dynamics

Rett syndrome (RTT) is a neurodevelopmental disorder that is a leading cause of severe cognitive and physical impairment. RTT typically occurs in females, although rare cases of males with the disease exist. Its genetic cause, symptoms, and clinical progression timeline have also become well-documented since its initial discovery. However, a relatively late diagnosis and lack of an available cure signify that our understanding of the disease is incomplete. Innovative research methods and tools are thereby helping to fill gaps in our knowledge of RTT. Specifically, mouse models of RTT, video analysis, and retrospective parental analysis are well-established tools that provide valuable insights into RTT. Moreover, current and anticipated treatment options are improving the quality of life of the RTT patient population. Collectively, these developments are creating optimistic future perspectives for RTT.

Mecp2 deletion results in profound alterations of developmental and adult functional connectivity

As a regressive neurodevelopmental disorder with a well-established genetic cause, Rett syndrome and its Mecp2 loss-of-function mouse model provide an excellent opportunity to define potentially translatable functional signatures of disease progression, as well as offer insight into the role of Mecp2 in functional circuit development. Thus, we applied widefield optical fluorescence imaging to assess mesoscale calcium functional connectivity (FC) in the Mecp2 cortex both at postnatal day (P)35 in development and during the disease-related decline. We found that FC between numerous cortical regions was disrupted in Mecp2 mutant males both in juvenile development and early adulthood. Female Mecp2 mice displayed an increase in homotopic contralateral FC in the motor cortex at P35 but not in adulthood, where instead more posterior parietal regions were implicated. An increase in the amplitude of connection strength, both with more positive correlations and more negative anticorrelations, was observed across the male cortex in numerous functional regions. Widespread rescue of MeCP2 protein in GABAergic neurons rescued none of these functional deficits, nor, surprisingly, the expected male lifespan. Altogether, the female results identify early signs of disease progression, while the results in males indicate MeCP2 protein is required for typical FC in the brain.

Quantitative electroencephalographic analysis as a potential biomarker of response to treatment with cannabidiol

PURPOSE

Pharmaceutical grade cannabidiol (CBD) is one of the newest anti-seizure medications for refractory epilepsy, and the effects of CBD on EEG have not been fully described.

METHODS

Patients enrolled in a CBD expanded access study had EEGs prior to and 12 weeks after initiation of CBD treatment for their refractory epilepsy. In addition to evaluating the clinical EEG reports, a nonbiased quantitative EEG (qEEG) analysis of background EEG was performed to determine whether consistent changes occur in the EEG in response to administration of CBD.

RESULTS

No significant qualitative changes were seen, nor changes in quantitative markers of EEG amplitude (RMS amplitude, standard deviation of the amplitude, skewness, or kurtosis), frequency (relative delta, theta, or alpha power), Spearman correlation, or coherence between brain regions. However, relative beta power and 1/f slope, a measure of signal noise increased with the addition of CBD. When patients were separated into responders and nonresponders based on seizure reduction with CBD, responders also had decreased Spearman correlation between the frontopolar and occipital regions after addition of CBD, suggesting that responders may have quantitatively improved EEG background organization after CBD initiation. The differences in beta and 1/f slope were also seen more robustly in CBD responders compared with nonresponders after CBD initiation. These differences disappeared when analyzing only patients not taking benzodiazepines, suggesting that the effect of CBD on seizures was related to the ability of the brain to further increase beta in response to CBD in patients already taking benzodiazepines. We noted that even before initiation of CBD, 1/f slope was also significantly different in responders compared to nonresponders. Therefore, to explore the baseline EEG in responders and nonresponders, we utilized a variable selection procedure to identify baseline EEG features that could predict whether a patient's seizures would improve with CBD. In the optimal multivariable logistic model, baseline coherence, Spearman correlation, and patient sex jointly predicted whether a patient in this cohort would respond to CBD (defined as a seizure reduction of 40% or greater) with 74% accuracy. This model performed less well on a data set of reduced duration and variability, highlighting the importance of real-world testing of any clinically relevant model.

CONCLUSION

These results suggest that there are subtle changes in certain metrics detected by qEEG even at baseline that may not be perceived during qualitative EEG analysis and that could be used in the future as a biomarker to predict a patient's clinical response to CBD administration. Development of such a predictive EEG biomarker, especially before the initiation of a medication trial, could reduce unnecessary ASM exposure and improve outcomes for patients with epilepsy facing new medication selection.

Impact of a Remotely Supervised Motor Rehabilitation Program on Maternal Well-Being During the COVID-19 Italian Lockdown

COVID-19 Lockdown was particularly challenging for most mothers of people with intellectual disabilities, including those with Rett syndrome (RTT), leading to feelings of abandonment from healthcare services of their children. Within those days, telerehabilitation has represented a valid alternative to support physical activity and treatment, supporting parents in structuring their children’s daily routine at home. This article aims to describe the well-being level of two groups of mothers of girls and women with RTT who were involved in a home-based remotely supervised motor rehabilitation program, respectively, before and during the COVID-19 Italian lockdown. Forty participants with classic RTT were recruited before the lockdown and randomly assigned to two groups that performed the intervention immediately before (Group 1) and during (Group 2) the lockdown, respectively. The intervention included an individualized daily physical activity program carried out for 12 weeks by participants’ parents and fortnightly supervised throughout Skype contacts to plan, monitor, and accommodate individual activities in the participant’s life at home. The short form Caregivers Well-Being Scale was collected for the mothers in each group 12 weeks before intervention (T1), at intervention initiation (T2), immediately after intervention termination (T3), as well as at 12 weeks after intervention termination (T4). Mothers of participants in the Group 1 showed a stable level of well-being across all four evaluations with a slight improvement during the lockdown, without significant change. Similarly, the well-being level of mothers in the Group 2 showed a statistically significant increase in their well-being between T2 and T3 (during the lockdown) and its reduction to the pre-intervention level between T3 and T4 (after the lockdown). The results suggest that the lockdown did not negatively affect the participants’ mothers’ well-being, leading to its improvement. Moreover, the proposed intervention could have supported the mothers in managing the new daily routine at home, positively affecting maternal well-being.

The GAIRS Checklist: a useful global assessment tool in patients with Rett syndrome

Background

Rett Syndrome is a severe, neurodevelopmental disorder mainly caused by mutations in the MECP2 gene, affecting around 1 in 10,000 female births. Severe physical, language, and social impairments impose a wide range of limitations in the assessment of the abilities of Rett patients. This study proposes an analysis and first validation of a Global Assessment and Intervention in Rett syndrome (GAIRS) Checklist for assessing behavioral, intellectual, academic, neuropsychological and psychosocial manifestations in patients with Rett Syndrome. We administered the GAIRS Checklist to 113 Italian patients with Rett Syndrome aged 4–42.

Aims of this study

To examine the psychometric characteristics of the GAIRS Checklist. Moreover, the aim is also to examine the validity of GAIRS with test–retest correlation, convergent validity with similar functional measurements, such as the Vineland scales, and divergent validity with severity of disease scale, such as the RARS scale and severity of neuropsychiatric evaluations.

Results

All 10 subscales of GAIRS were positively and significantly related to each other and to the total GAIRS score, and the subscales showed high levels of Cronbach’s alpha values (from .77 to .95). Principal axis factoring suggested two factors that explain 60% of the variance. Test–retest reliability is 0.82. This means that psychometric properties are reliable. Correlation for Concurrent validity with Vineland score was high and Divergent Validity with RARS was also high.

Conclusion

The GAIRS Checklist used for Rett syndrome is acceptable and feasible to complete assessment in a clinical setting. Moreover, it can detect the complexity of this disease and may suggest the next step in terms of specific training in Rett syndrome.

Cognitive stimulation has potential for brain activation in individuals with Rett syndrome

BACKGROUND

Knowledge regarding neuropsychological training in Rett syndrome (RS) is scarce. The aim of this study was to assess the outcome and the duration of the effect of cognitive stimulation on topographic electroencephalography (EEG) data in RS.

METHODS

Twenty female children diagnosed with RS were included in the analysis. Girls with RS conducted a cognitive task using an eye-tracker designed to evaluate access and choice skills. EEG data were acquired during the experimental procedure including two 10-min baseline stages before and after the task. Topographical changes of several EEG spectral markers including absolute and relative powers, Brain Symmetry Index and entropy were assessed.

RESULTS

Topographic significance probability maps suggested statistical decreases on delta activity and increases on beta rhythm associated with the cognitive task. Entropy increased during and after the task, likely related to more complex brain activity. A significant positive interaction was obtained between Brain Symmetry Index and age showing that the improvement of interhemispheric symmetry was higher in younger girls (5-10 years).

CONCLUSIONS

According to our findings, significant alterations of brain rhythms were observed during and after cognitive stimulation, suggesting that cognitive stimulation may have effects on brain activity beyond the stimulation period. Finally, our promising results also showed an increase brain symmetry that was especially relevant for the younger group. This could suggest an interaction of the eye-tracking cognitive task; however, further studies in this field are needed to assess the relation between brain asymmetries and age.

Choosing Strategies to Deal with Artifactual EEG Data in Children with Cognitive Impairment

Rett syndrome is a disease that involves acute cognitive impairment and, consequently, a complex and varied symptomatology. This study evaluates the EEG signals of twenty-nine patients and classify them according to the level of movement artifact. The main goal is to achieve an artifact rejection strategy that performs well in all signals, regardless of the artifact level. Two different methods have been studied: one based on the data distribution and the other based on the energy function, with entropy as its main component. The method based on the data distribution shows poor performance with signals containing high amplitude outliers. On the contrary, the method based on the energy function is more robust to outliers. As it does not depend on the data distribution, it is not affected by artifactual events. A double rejection strategy has been chosen, first on a motion signal (accelerometer or EEG low-pass filtered between 1 and 10 Hz) and then on the EEG signal. The results showed a higher performance when working combining both artifact rejection methods. The energy-based method, to isolate motion artifacts, and the data-distribution-based method, to eliminate the remaining lower amplitude artifacts were used. In conclusion, a new method that proves to be robust for all types of signals is designed.

Electrophysiological Biomarkers in Genetic Epilepsies

Precision treatments for epilepsy targeting the underlying genetic diagnoses are becoming a reality. Historically, the goal of epilepsy treatments was to reduce seizure frequency. In the era of precision medicine, however, outcomes such as prevention of epilepsy progression or even improvements in cognitive functions are both aspirational targets for any intervention. Developing methods, both in clinical trial design and in novel endpoints, will be necessary for measuring, not only seizures, but also the other neurodevelopmental outcomes that are predicted to be targeted by precision treatments. Biomarkers that quantitatively measure disease progression or network level changes are needed to allow for unbiased measurements of the effects of any gene-level treatments. Here, we discuss some of the promising electrophysiological biomarkers that may be of use in clinical trials of precision therapies, as well as the difficulties in implementing them.

The role of a virtual avatar in attention and memory tasks in Rett syndrome

Background

Since subjects with Rett syndrome (RTT) focus their attention mainly on the faces of people with whom they interact, in this study the role of a human-like smart interactive agent (an avatar) in enhancing cognitive processes is examined. More in depth, this study aimed to understand if, and to what extent, the use of an avatar can improve attention and memory abilities in subjects with RTT.

Method

Thirty-six subjects with RTT participated in the study. All participants performed over-selectivity and memory tasks, for a total of six trials. These trials were randomly presented in two different conditions: with and without virtual avatar.

Results

The results indicated that the participants improved their attention and memory abilities when they performed the tasks with the avatar. There were no improvements when they performed the tasks without the avatar.

Discussion

The results were discussed considering the relationship between motivation, attention and memory in RTT.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02212-w.

Reviewing Evidence for the Relationship of EEG Abnormalities and RTT Phenotype Paralleled by Insights from Animal Studies

Rett syndrome (RTT) is a rare neurodevelopmental disorder that is usually caused by mutations of the MECP2 gene. Patients with RTT suffer from severe deficits in motor, perceptual and cognitive domains. Electroencephalogram (EEG) has provided useful information to clinicians and scientists, from the very first descriptions of RTT, and yet no reliable neurophysiological biomarkers related to the pathophysiology of the disorder or symptom severity have been identified to date. To identify consistently observed and potentially informative EEG characteristics of RTT pathophysiology, and ascertain areas most worthy of further systematic investigation, here we review the literature for EEG abnormalities reported in patients with RTT and in its disease models. While pointing to some promising potential EEG biomarkers of RTT, our review identify areas of need to realize the potential of EEG including (1) quantitative investigation of promising clinical-EEG observations in RTT, e.g., shift of mu rhythm frequency and EEG during sleep; (2) closer alignment of approaches between patients with RTT and its animal models to strengthen the translational significance of the work (e.g., EEG measurements and behavioral states); (3) establishment of large-scale consortium research, to provide adequate Ns to investigate age and genotype effects.

Longitudinal cognitive rehabilitation applied with eye-tracker for patients with Rett Syndrome

BACKGROUND

longitudinal effects of cognitive rehabilitation in Rett Syndrome (RTT) have been poorly investigated and the mechanisms do not appear to have been described in detail.

AIMS

the aim of this study was to examine the effects of cognitive rehabilitation with eye-tracker technology on attention, choice behaviours and language over a 2-year period in patients with RTT.

METHODS AND PROCEDURES

28 participants with RTT, ranging from age 4-22 years old (M = 13.85 years, SD = 5.89), received 30 min of cognitive rehabilitation with eye-tracker for 3 days a week over a 1-month for 2 years. They then underwent cognitive assessment to evaluate attention, choice, language and global functioning in four specific times: before cognitive rehabilitation (T1), after six months of cognitive rehabilitation (T2), six months after the second cognitive rehabilitation phase (T3) and at the end of the third cognitive rehabilitation phase (T4).

OUTCOME AND RESULTS

patients with RTT show long-term improvements in seconds of attention and number of choice behaviours, with barely any improvement in global functioning. No improvement in language was found.

CONCLUSIONS AND IMPLICATIONS

this is the first study aimed at examining longitudinal effects of cognitive rehabilitation in patients with RTT, demonstrating a linear improvement across time in attention and choice.

Effects of short- and long-term neurostimulation (tDCS) on Alzheimer's disease patients: two randomized studies

BACKGROUND

Non-invasive brain stimulation is an effective treatment for Alzheimer's disease.

AIMS

The purpose of the two studies presented here is to compare the short- and long-term effects of transcranial direct current stimulation (t-DCS) on two samples of advanced AD patients.

METHODS

In Study 1 26 patients were involved in a 10-day anodal vs. sham tDCS intervention stimulating the left frontotemporal cortex. A pre-post test assessment was run using two different neurocognitive tests and EEG data. The same protocol was used in Study 2, which involved 18 different patients who underwent the same intervention 10 days a month for 8 months.

RESULTS

Results confirmed how the t-DCS intervention was effective both in the short- and the long-term to slow down the progression of AD on specific neurophysiological domains and, to a certain extent, on neurophysiological activity. Discussion tDCS appear to be effective and to affect differently neurocognitive and neurophysiological functions when comparing short and long-term outcomes. Conclusions Anodal-tDCS is an effective way to slow down the progression of Alzheimer's both in the short and long term. It can also affect the EEG patterns, but this requires a more protracted intervention.

Noninvasive Continuous Monitoring of Vital Signs With Wearables: Fit for Medical Use?

BACKGROUND

Wearables (= wearable computer) enable continuous and noninvasive monitoring of a range of vital signs. Mobile and cost-effective devices, combined with powerful data analysis tools, open new dimensions in assessing body functions ("digital biomarkers").

METHODS

To answer the question whether wearables are ready for use in the medical context, a PubMed literature search and analysis for their clinical-scientific use using publications from the years 2008 to 2018 was performed.

RESULTS

A total of 79 out of 314 search hits were publications on clinical trials with wearables, of which 16 were randomized controlled trials. Motion sensors were most frequently used to measure defined movements, movement disorders, or general physical activity. Approximately 20% of the studies used sensors to detect cardiovascular parameters. As for the sensor location, the wrist was chosen in most studies (22.8%).

CONCLUSION

Wearables can be used in a precisely defined medical context, when taking into account complex influencing factors.

Rehabilitation therapies in Rett syndrome across the lifespan: A scoping review of human and animal studies

PURPOSE

To perform a scoping review of the evidence for therapeutic interventions to manage functional impairments associated with Rett syndrome (RTT) throughout the lifespan.

METHODS

MEDLINE, EMBASE, PsycINFO, CENTRAL, CINAHL, Scopus and Index to Chiropractic Literature were searched systematically up to December 2019. Two investigators independently reviewed all search results and extracted those that met the inclusion criteria. Human and animal model studies pertaining to therapies that increase functional ability or treat RTT-associated symptoms in all age groups were included. Relevant studies were grouped into intervention categories and rated using the Oxford Centre of Evidence Based Medicine Levels of Evidence. Demographics of participants, interventions, and outcomes were summarized.

RESULTS

Ninety-one articles representing 88 studies met the inclusion criteria, of which 80 were human clinical studies and eight were studies using animal models. Study designs were primarily case series and only six studies involved participants above the age of 40.

CONCLUSION

A small number of rigorously studied rehabilitation interventions have been published. Published studies aim to address a wide variety of functional impairments. Research regarding implementation of therapies for older patients with RTT is lacking and requires further exploration.

Induction of long-term potentiation at Schaffer collateral-CA1 synapses in mice hippocampus after IMPX977 administration

Objective

To investigate the effects of IMPX977 on long term potentiation (LTP) at Schaffer collateral-CA1 synapses in vitro and on methyl CpG binding protein 2 (Mecp2) expression in mice cortex and hippocampus.

Methods

Thirty-two C57BL/6 mice were randomly divided into four groups: control, olive oil (vehicle), IMPX977 low (5 mg/kg) and high (15 mg/kg) groups. Mice were administrated every other day orally for two weeks. Extracellular recording technique in vitro was used to record the effects of IMPX977 on Schaffer collateral-CA1 LTP pathway in acute mice hippocampal slices. The Mecp2 protein expression level was detected by Western blotting.

Results

Compared to the control group, vehicle did not alter the synaptic transmission in Schaffer collateral-CA1 synapses, however, IMPX977 at concentrations of 5 mg/kg and 15 mg/kg significantly enhanced fEPSP (field excitatory postsynaptic potential) slope in Schaffer collateral-CA1 pathway to (179.6 ± 17.8)% and (191.4 ± 21.4)%, individually 60 min after HFS, IMPX977 improved LTP induction significantly at Schaffer collateral-CA1 pathway at least. Also, IMPX977 significantly elevated MeCP2 protein level in cortex.

Conclusion

The effects of IMPX977 on synaptic transmission and Mecp2 protein expression provided convincing evidence that IMPX977 could be promising new drug candidates for Rett syndrome treatment.

Beyond Technologies of Electroencephalography-Based Brain-Computer Interfaces: A Systematic Review From Commercial and Ethical Aspects

The deployment of electroencephalographic techniques for commercial applications has undergone a rapid growth in recent decades. As they continue to expand in the consumer markets as suitable techniques for monitoring the brain activity, their transformative potential necessitates equally significant ethical inquiries. One of the main questions, which arises then when evaluating these kinds of applications, is whether they should be aligned or not with the main ethical concerns reported by scholars and experts. Thus, the present work attempts to unify these disciplines of knowledge by performing a comprehensive scan of the major electroencephalographic market applications as well as their most relevant ethical concerns arising from the existing literature. In this literature review, different databases were consulted, which presented conceptual and empirical discussions and findings about commercial and ethical aspects of electroencephalography. Subsequently, the content was extracted from the articles and the main conclusions were presented. Finally, an external assessment of the outcomes was conducted in consultation with an expert panel in some of the topic areas such as biomedical engineering, biomechatronics, and neuroscience. The ultimate purpose of this review is to provide a genuine insight into the cutting-edge practical attempts at electroencephalography. By the same token, it seeks to highlight the overlap between the market needs and the ethical standards that should govern the deployment of electroencephalographic consumer-grade solutions, providing a practical approach that overcomes the engineering myopia of certain ethical discussions.

Vagus nerve stimulation paired with tones restores auditory processing in a rat model of Rett syndrome

BACKGROUND

Rett syndrome is a rare neurological disorder associated with a mutation in the X-linked gene MECP2. This disorder mainly affects females, who typically have seemingly normal early development followed by a regression of acquired skills. The rodent Mecp2 model exhibits many of the classic neural abnormalities and behavioral deficits observed in individuals with Rett syndrome. Similar to individuals with Rett syndrome, both auditory discrimination ability and auditory cortical responses are impaired in heterozygous Mecp2 rats. The development of therapies that can enhance plasticity in auditory networks and improve auditory processing has the potential to impact the lives of individuals with Rett syndrome. Evidence suggests that precisely timed vagus nerve stimulation (VNS) paired with sound presentation can drive robust neuroplasticity in auditory networks and enhance the benefits of auditory therapy.

OBJECTIVE

The aim of this study was to investigate the ability of VNS paired with tones to restore auditory processing in Mecp2 transgenic rats.

METHODS

Seventeen female heterozygous Mecp2 rats and 8 female wild-type (WT) littermates were used in this study. The rats were exposed to multiple tone frequencies paired with VNS 300 times per day for 20 days. Auditory cortex responses were then examined following VNS-tone pairing therapy or no therapy.

RESULTS

Our results indicate that Mecp2 mutation alters auditory cortex responses to sounds compared to WT controls. VNS-tone pairing in Mecp2 rats improves the cortical response strength to both tones and speech sounds compared to untreated Mecp2 rats. Additionally, VNS-tone pairing increased the information contained in the neural response that can be used to discriminate between different consonant sounds.

CONCLUSION

These results demonstrate that VNS-sound pairing may represent a strategy to enhance auditory function in individuals with Rett syndrome.

Rehabilitation interventions in Rett syndrome: a scoping review

AIM

To summarize existing interventions and their outcomes in Rett syndrome (RTT) rehabilitation and identify gaps in the literature.

METHOD

Five databases (Ovid MEDLINE, Ovid Embase Classic, Ovid PsycINFO, EBSCO CINAHL Plus, and ProQuest ERIC) were systematically searched up to 23rd July 2018 for studies describing rehabilitation interventions. Data on study participants, design, and outcomes were extracted.

RESULTS

Sixty-two articles were included in the final review. Evidence consistently demonstrated that females with RTT can improve their gross motor, fine motor, and communicative skills with rehabilitation. All 11 interventions targeting gross motor function, namely ambulation, achieved functional improvements. Twenty of 24 articles describing fine motor rehabilitation studies succeeded in decreasing stereotypies, improving functional hand use, and/or reducing self-injurious behaviors. Twenty-one of 22 studies describing communication interventions succeeded in training choice-making, communicative language, or socialization behavior. Other key findings include the positive interplay between physical and communicative rehabilitation outcomes, and the ability of females with RTT to improve their cognitive abilities during intervention.

INTERPRETATION

Rehabilitation can impact the daily lives of females with RTT and their caregivers in clinically meaningful ways.

Evoked Potentials and EEG Analysis in Rett Syndrome and Related Developmental Encephalopathies: Towards a Biomarker for Translational Research

Rett syndrome is a debilitating neurodevelopmental disorder for which no disease-modifying treatment is available. Fortunately, advances in our understanding of the genetics and pathophysiology of Rett syndrome has led to the development of promising new therapeutics for the condition. Several of these therapeutics are currently being tested in clinical trials with others likely to progress to clinical trials in the coming years. The failure of recent clinical trials for Rett syndrome and other neurodevelopmental disorders has highlighted the need for electrophysiological or other objective biological markers of treatment response to support the success of clinical trials moving forward. The purpose of this review is to describe the existing studies of electroencephalography (EEG) and evoked potentials (EPs) in Rett syndrome and discuss the open questions that must be addressed before the field can adopt these measures as surrogate endpoints in clinical trials. In addition to summarizing the human work on Rett syndrome, we also describe relevant studies with animal models and the limited research that has been carried out on Rett-related disorders, particularly methyl-CpG binding protein 2 (MECP2) duplication syndrome, CDKL5 deficiency disorder, and FOXG1 disorder.

Effects of Combined Transcranial Direct Current Stimulation with Cognitive Training in Girls with Rett Syndrome

Background: Transcranial Direct Current Stimulation (tDCS) combined with traditional rehabilitative techniques has not been widely applied to Rett Syndrome (RTT). The aim of this study was to examine the effects of combined cognitive traditional training with tDCS applied to attention and language measures in subjects with RTT. Methods: 31 subjects with RTT were randomly allocated into two groups: non-sham tDCS (n = 18) and sham tDCS (n = 13). The former received the integrated intervention non-sham tDCS plus cognitive empowerment during the treatment phase. The latter received sham stimulation plus cognitive empowerment. All participants underwent neurological and cognitive assessment to evaluate attention and language measures: before integrated treatment (pre-test phase), at the conclusion of the treatment (post-test phase), and at 1 month after the conclusion of the treatment (follow-up phase). Results: the results indicated longer attention time in the non-sham tDCS group compared to the sham tDCS group with a stable trend also in the follow-up phase; an increase of the number of vowel/phoneme sounds in the non-sham tDCS group; and an improvement in the neurophysiological parameters in the non-sham tDCS group. Conclusions: This study supports the use of tDCS as a promising and alternative approach in the RTT rehabilitation field.

The TCTRS Project: A Holistic Approach for Telerehabilitation in Rett Syndrome

Telerehabilitation (TR) has been proven to be an effective tool in improving the adaptive skills of children and young adults with Multiple Disabilities (MDs). The application of a comprehensive set of new technologies reveals new opportunities for both physical and cognitive telerehabilitation, but there is no holistic approach in the case of genetic syndromes. In this paper we present reflections and early results of the TCTRS project that aims at implementing a telerehabilitation system capable of offering complete coverage of rehabilitation needs for people with Rett Syndrome, from both the physical and cognitive points of view. Moreover, the data acquired through the system can also represent a basis for machine learning applications to remotely support therapists and physicians. Our first tests on the system application show the great potential of our approach, in terms of feasibility and applicability, for both rehabilitation centers and families.

Caregiver- and Clinician-Reported Adaptive Functioning in Rett Syndrome: a Systematic Review and Evaluation of Measurement Strategies

Rett syndrome is the second most common cause of intellectual disability in females worldwide. The severity of many individuals' impairment limits the effectiveness of traditional assessment. However, clinician and parent reports of adaptive functioning may provide insight into these patients' abilities. This review aims to synthesize the current literature assessing adaptive functioning in Rett syndrome and evaluate existing measurement tools in this population. A search was conducted on PubMed using the search term "Rett syndrome." Studies that quantitatively assessed adaptive functioning outcomes in Rett syndrome with published and normed questionnaire measures were included. Twenty-three studies met inclusion criteria. Overall results indicate that the population of people with Rett syndrome is highly impaired, both in overall adaptive functioning as well as in specific subdomains (e.g., mobility, activities of daily living). Atypical Rett syndrome groups performed better on measures of adaptive functioning relative to patients with classic Rett syndrome. Our findings identified measurement weaknesses, as many of the studies found floor effects and therefore were unable to capture meaningful variability in outcomes. Individuals with Rett syndrome are highly reliant on caregivers due to disrupted adaptive functioning abilities. Optimizing measurement of adaptive skills in Rett syndrome will facilitate the quantification of meaningful change in skills and the identification of efficacious interventions aimed at improving outcomes and quality of life.

Experimental Examination and Social Validation of a Microswitch Intervention to Improve Choice-Making and Activity Engagement for Six Girls with Rett Syndrome

Background: The use of assistive technology, specifically microswitches, with children with RTT has been shown to effectively moderate the impact of their disability on their quality of life^- by facilitating access to meaningful leisure and other activities. Objectives: This study aimed to evaluate the effectiveness of a microswitch intervention on increased choice making, engagement in a targeted sorting activity, and indices of happiness, and decreased stereotypic behaviors for six girls with Rett syndrome. Targeted dependent variables were also assessed at six months post-intervention. Following the intervention study, 90 external raters completed a social validation procedure. Method: An ABABAB experimental sequence was implemented for each participant with a cross-over effect. A social validation assessment involving 90 external raters was carried out. Results: Data emphasized an improved performance for each participants involved (i.e., adaptive responses). Five participants showed a capacity of independent choice. One participant seemed to be closely linked to the position of the container. Social raters favorably endorsed the use of the program since they positively evaluated the use of the technology on all the dimensions investigated. Conclusion: A microswitch intervention may improve choice making and activity engagement for children with Rett syndrome. Further research is needed on the development of more sophisticated forms of individualized technological options to improve opportunities for enhanced engagement and choice-making for individuals with RTT.

Brain functional connectivity after cognitive-bias modification and behavioral changes in abstinent alcohol-use disorder patients

The use of the cognitive-bias modification (CBM) method has emerged as a therapeutic complement in the treatment of alcoholism, producing changes at behavioral and brain level. Nevertheless, the impact of the CBM procedure could be improved by the memory retrieval-extinction process (REP). Different studies have demonstrated that the retrieval of drug memories before extinction training later reduced the reinstatement of drug-seeking behavior. The main aim of this work was to study the effect of the CBM procedure itself, as well as in combination with the activation of alcohol-related memories, on the brain oscillatory activity of abstinent patients with alcohol-use disorder. The study sample comprised 33 patients divided into three groups: A-CBM (alcohol-related memory activation + CBM), N-CBM (neutral memory activation + CBM) and N-INT (no-intervention) groups. A resting-state EEG was obtained before and after each protocol, along with the assessment of the automatic action tendencies. A-CBM group showed a general alpha synchronization increase after the protocol, while the other groups did not show any significant change. Besides, A-CBM group showed significant intra and inter-group differences in the automatic action tendencies after the protocol, reflected in higher avoidance bias toward appetitive, aversive and without context alcohol-related stimuli. The alpha phase synchronization increase could be the neural manifestation of the conditioning produced between the alcohol-related stimuli and the automatic avoidance response. Moreover, the activation of the alcohol-related memories favors this conditioning with those alcohol-related stimuli associated with the activated memories, because it increases their threat level for the abstinence maintenance.

Sensory Integration and Functional Reaching in Children With Rett Syndrome/Rett-Related Disorders

Background

The loss of functional hand skills is a primary characteristic of Rett syndrome. Stereotypies, dyspraxia, and other sensory processing issues severely limit the individual's ability to reach toward and sustain grasp on objects. This loss of functional reach and grasp severely limits their ability to participate in self-help, play, and school-related activities. We proposed that Ayres Sensory Integration (ASI) treatment would improve sensory processing and motor planning, which would lay the sensory-motor groundwork for improving grasp of objects, an important first step in developing functional hand use.

Objective

We examined effects of ASI treatment on rate of reaching and grasping for children with Rett syndrome/Rett-related disorders.

Methods

We used an interrupted time series design to measure changes in outcome variables occurring after intervention initiation and cessation. We analyzed daily video observations during baseline, intervention, and post-intervention periods, over a span of 7 months.

Results

During baseline, rate of grasping declined moderately. There was a 15% increase in grasping from the end of baseline to end of the post-intervention period. There was no significant change in rate of reaching.

Conclusions

This study provides preliminary data showing very small improvements in hand grasp of children with Rett syndrome following ASI treatment; larger studies in diverse settings are needed to establish the effectiveness of this approach. This study shows that an interrupted time series research design provides a valid template for evaluating interventions for children with rare disorders.

The Treatment of Hypersalivation in Rett Syndrome with Botulinum Toxin: Efficacy and Clinical Implications

INTRODUCTION

Subjects with Rett syndrome (RS) develop invariably severe motor deterioration resulting in swallowing difficulties that may produce excessive drooling. Hypersalivation can cause discomfort due to hygienic problems and may complicate with oral and respiratory dysfunctions. The aim of this study is to evaluate the response to treatment with botulinum toxin (BTX) for hypersalivation and to identify possible benefits of saliva reduction on oral motor and respiratory disorders of patients with RS.

METHODS

Five consecutive patients with RS and hypersalivation were treated with incobotulinumtoxin A injected in salivary glands with ultrasound guidance. Severity of excessive drooling was assessed with the Thomas-Stonell and Greenberg Scale (TGSC) and the clinical impact of the treatment was evaluated using three selected items of RS Assessment Rating Scale (R.A.R.S.): eating habits, dyspnoea and bruxism. Scale rating was performed before BTX injection (T0), 4 (T1) and 12 (T2) weeks after.

RESULTS

Scores of TGSC and R.A.R.S. (for eating and bruxism) were reduced significantly after therapy at T1.

CONCLUSIONS

BTX treatment for sialorrhea in RS is effective in reducing saliva production and may also improve oral motor functions.

The potential of eye-tracking as a sensitive measure of behavioural change in response to intervention

One challenge to the development of effective interventions to support learning and behavioural change in neurodevelopmental disorders is a lack of suitable outcome measures. Eye-tracking has been used widely to chart cognitive development and clinically-relevant group differences in many populations. This proof-of-concept study investigates whether it also has the potential to act as a marker of treatment effects, by testing its sensitivity to differential change over a short period of exposure to an iPad app in typically developing children. The app targets a key skill in early social communication development, by rewarding attention to people, operationalised via a finger-tap on screen. We measured attention to images taken from the app, and a selection of matched stimuli to test generalisation of effects, at baseline and two weeks later. Children were assigned to either an app-exposure or no-app condition in the intervening period. The app exposure group showed increases in fixation on people for images from the app, and for distant-generalisation photographs, at high levels of complexity. We conclude that, with careful selection of stimuli, eye-tracking has the potential to make a valuable contribution to the range of outcome measures available for psycho-behavioural interventions in neurodevelopmental disorders.

Key issues in Rett syndrome: emotional, behavioural and autonomic dysregulation (EBAD) - a target for clinical trials

Complex neurodevelopmental disorders need multi-disciplinary treatment approaches for optimal care. The clinical effectiveness of treatments is limited in patients with rare genetic syndromes with multisystem morbidity. Emotional and behavioural dysregulation is common across many neurodevelopmental disorders. It can manifest in children across multiple diagnostic groups, including those on the autism spectrum and in rare genetic syndromes such as Rett Syndrome (RTT). There is, however a remarkable scarcity in the literature on the impact of the autonomic component on emotional and behavioural regulation in these disorders, and on the longer-term outcomes on disorder burden.RTT is a debilitating and often life-threatening disorder involving multiple overlapping physiological systems. Autonomic dysregulation otherwise known as dysautonomia is a cardinal feature of RTT characterised by an imbalance between the sympathetic and parasympathetic arms of the autonomic nervous system. Unlocking the autonomic component of emotional and behavioural dysregulation would be central in reducing the impairment seen in patients with RTT. In this vein, Emotional, Behavioural and Autonomic Dysregulation (EBAD) would be a useful construct to target for treatment which could mitigate burden and improve the quality of life of patients.RTT can be considered as a congenital dysautonomia and because EBAD can give rise to impairments occurring in multiple overlapping physiological systems, understanding these physiological responses arising out of EBAD would be a critical part to consider when planning treatment strategies and improving clinical outcomes in these patients. Biometric guided pharmacological and bio-feedback therapy for the behavioural and emotional aspects of the disorder offers an attracting perspective to manage EBAD in these patients. This can also allow for the stratification of patients into clinical trials and could ultimately help streamline the patient care pathway for optimal outcomes.The objectives of this review are to emphasise the key issues relating to the management of EBAD in patients with RTT, appraise clinical trials done in RTT from the perspective of autonomic physiology and to discuss the potential of EBAD as a target for clinical trials.

Neurophysiological and cognitive effects of Transcranial Direct Current Stimulation in three girls with Rett Syndrome with chronic language impairments

BACKGROUND

this study was based on both neurophysiological decelerated activity and communication deficits in Rett Syndrome (RTT).

AIMS

the aim was to examine the neurophysiological and cognitive effects of Transcranial Direct Current Stimulation (tDCS) in three girls with RTT with chronic language impairments.

METHODS AND PROCEDURES

we proposed an integrated intervention: tDCS and cognitive empowerment applied to language in order to enhance speech production (new functional sounds and new words). Because maximal gains usually are achieved when tDCS is coupled with behavioral training, we applied tDCS stimulation on Broca's area together with linguistic training.

OUTCOMES AND RESULTS

the results indicated a general enhancement in language abilities (an increase in the number of vowel/consonant sounds and words and the production and comprehension through discrimination), motor coordination (functional movements), and neurophysiological parameters (an increase in the frequency and power of alpha, beta and theta bands).

CONCLUSION AND IMPLICATIONS

we assume that tDCS stimulation combined with the cognitive empowerment applied to language can significantly influence a chronic impairment even in genetic syndromes. Our results provide data that support the role of tDCS in fostering brain plasticity and in particular in empowering speech production and comprehension in girls with RTT.