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1.
Brain Sci ; 13(11)2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-38002531

RESUMEN

Autism Spectrum Disorder (ASD) affects millions of individuals worldwide, and there is growing interest in the use of extended reality (XR) technologies for intervention. Despite the promising potential of XR interventions, there remain gaps in our understanding of the neurobiological mechanisms underlying ASD, particularly in relation to sex-based differences. This scoping review synthesizes the current research on brain activity patterns in ASD, emphasizing the implications for XR interventions and neurofeedback therapy. We examine the brain regions commonly affected by ASD, the potential benefits and drawbacks of XR technologies, and the implications of sex-specific differences for designing effective interventions. Our findings underscore the need for ongoing research into the neurobiological underpinnings of ASD and sex-based differences, as well as the importance of developing tailored interventions that consider the unique needs and experiences of autistic individuals.

2.
Bioengineering (Basel) ; 10(1)2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36671670

RESUMEN

Autism spectrum disorder (ASD) is a heterogeneous disorder that affects several behavioral domains of neurodevelopment. Transcranial direct current stimulation (tDCS) is a new method that modulates motor and cognitive function and may have potential applications in ASD treatment. To identify its potential effects on ASD, differences in electroencephalogram (EEG) microstates were compared between children with typical development (n = 26) and those with ASD (n = 26). Furthermore, children with ASD were divided into a tDCS (experimental) and sham stimulation (control) group, and EEG microstates and Autism Behavior Checklist (ABC) scores before and after tDCS were compared. Microstates A, B, and D differed significantly between children with TD and those with ASD. In the experimental group, the scores of microstates A and C and ABC before tDCS differed from those after tDCS. Conversely, in the control group, neither the EEG microstates nor the ABC scores before the treatment period (sham stimulation) differed from those after the treatment period. This study indicates that tDCS may become a viable treatment for ASD.

3.
Brain Sci ; 13(1)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36672111

RESUMEN

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder that interferes with normal brain development. Brain connectivity may serve as a biomarker for ASD in this respect. This study enrolled a total of 179 children aged 3-10 years (90 typically developed (TD) and 89 with ASD). We used a weighted phase lag index and a directed transfer function to investigate the functional and effective connectivity in children with ASD and TD. Our findings indicated that patients with ASD had local hyper-connectivity of brain regions in functional connectivity and simultaneous significant decrease in effective connectivity across hemispheres. These connectivity abnormalities may help to find biomarkers of ASD.

4.
Transl Stroke Res ; 14(6): 854-862, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36369294

RESUMEN

Near-infrared laser therapy, a special form of transcranial light therapy, has been tested as an acute stroke therapy in three large clinical trials. While the NEST trials failed to show the efficacy of light therapy in human stroke patients, there are many lingering questions and lessons that can be learned. In this review, we summarize the putative mechanism of light stimulation in the setting of stroke, highlight barriers, and challenges during the translational process, and evaluate light stimulation parameters, dosages and safety issues, choice of outcomes, effect size, and patient selection criteria. In the end, we propose potential future opportunities with transcranial light stimulation as a cerebroprotective or restorative tool for future stroke treatment.


Asunto(s)
Isquemia Encefálica , Terapia por Láser , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Isquemia Encefálica/terapia , Accidente Cerebrovascular/terapia , Estimulación Magnética Transcraneal
5.
Front Neurosci ; 17: 1277786, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38274502

RESUMEN

Introduction: Many studies have collected normative developmental EEG data to better understand brain function in early life and associated changes during both aging and pathology. Higher cognitive functions of the brain do not normally stem from the workings of a single brain region that works but, rather, on the interaction between different brain regions. In this regard studying the connectivity between brain regions is of great importance towards understanding higher cognitive functions and its underlying mechanisms. Methods: In this study, EEG data of children (N = 253; 3-10 years old; 113 females, 140 males) from pre-school to schoolage was collected, and the weighted phase delay index and directed transfer function method was used to find the electrophysiological indicators of both functional connectivity and effective connectivity. A general linear model was built between the indicators and age, and the change trend of electrophysiological indicators analyzed for age. Results: The results showed an age trend for the functional and effective connectivity of the brain of children. Discussion: The results are of importance in understanding normative brain development and in defining those conditions that deviate from typical growth trajectories.

6.
Med Biol Eng Comput ; 60(12): 3655-3664, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36282407

RESUMEN

To compare the differences in directed connectivity between typically developing (TD) and autism spectrum disorder (ASD) children and identify the potential effects of repetitive transcranial magnetic stimulation (rTMS) on brain connectivity and behavior of children with ASD; 26 TD children (18 males/8 females; the average age was 6.34 ± 0.45) and 30 ASD children (21 males/9 females; the average age was 6.42 ± 0.17) participated in the experiment. ASD children were divided randomly into an experimental group and a control group. The experimental group received 18 rTMS sessions (twice a week for nine weeks), whereas the control group received the same procedures with sham stimulation. Directed transfer function (DTF) was used to calculate the effective connectivity as a way of investigating differences between ASD and TD children while simultaneously evaluating the effectiveness of rTMS for ASD. The results illustrate that the DTF of TD children in the frontal lobe (Fp1, Fp2, F7, F8) and temporal lobe (T7, T8) is higher than that of ASD children in all frequency bands; however, the DTF of ASD children is higher than TD in the midline (Fz, Cz), central lobe (C3, C4), and parietal lobe (P3, P4). In the experimental group of ASD children, the effective connectivity decreased from O1 to T7 and from P7 to Fp1 in the alpha band and from Pz to T8 in the gamma band after stimulation. Significant changes in Autism Behavior Checklist (ABC) scores were also found in social behaviors. Effective connectivity derived from DTF distinguishes ASD from TD children. rTMS provides changes in connectivity and behavior, suggesting its potential use as a viable treatment option for ASD individuals.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Niño , Masculino , Femenino , Humanos , Preescolar , Estimulación Magnética Transcraneal/métodos , Trastorno Autístico/terapia , Trastorno del Espectro Autista/terapia , Proyectos Piloto , Encéfalo/fisiología , Electroencefalografía/métodos
7.
Comput Biol Med ; 141: 105167, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34959111

RESUMEN

OBJECTIVE: To explore whether 1 Hz repetitive transcranial magnetic stimulation (rTMS) has positive effects on brain activity and behavior of autistic children with intellectual disability. METHODS: 32 autistic children with intellectual disability (26 boys and 6 girls) were recruited to participate in this feasibility study. The autistic children were divided randomly and equally into an experimental group and a control group. 16 children (three girls and 13 boys; mean ± SD age: 7.8 ± 2.1 years) who received rTMS treatment twice a week were served as the experimental group, while 16 children (three girls and 13 boys; mean ± SD age: 7.2 ± 1.6 years) with sham stimulation were considered as the control group. Recurrence quantification analysis (RQA) was employed to quantify the nonlinear features of electroencephalogram (EEG) signals recorded during the resting state. Three RQA measures, including recursive rate (RR), deterministic (DET) and mean diagonal length (L) were extracted from the EEG signals to characterize the deterministic features of cortical activity. RESULTS: Significant differences in RR and DET were observed between the experimental group and the control group. We also found discernible discrepancies in the Autism Behavior Checklist (ABC) score pre- and post-rTMS for the experimental group. CONCLUSIONS: 1 Hz repetitive transcranial magnetic stimulation (rTMS) could positively influence brain activity and behavior of autistic children with intellectual disability.


Asunto(s)
Trastorno Autístico , Discapacidad Intelectual , Trastorno Autístico/terapia , Niño , Preescolar , Electroencefalografía , Femenino , Humanos , Masculino , Proyectos Piloto , Estimulación Magnética Transcraneal
8.
Trials ; 22(1): 594, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34488824

RESUMEN

BACKGROUND: Post-traumatic stress disorder (PTSD) is a significant public health problem, affecting approximately 7% of the general population and 13-18% of the combat Veteran population. The first study using acupuncture for PTSD in a civilian population showed large pre- to post-treatment effects for an empirically developed verum protocol, which was equivalent to group cognitive behavior therapy and superior to a wait-list control. The primary objective of this study is to determine both clinical and biological effects of verum acupuncture for combat-related PTSD in treatment-seeking US Veterans. METHODS: This is a two-arm, parallel-group, prospective randomized placebo-controlled clinical trial. The experimental condition is verum acupuncture and the placebo control is sham (minimal) acupuncture in 1-h sessions, twice a week for 12 weeks. Ninety subjects will provide adequate power and will be allocated to group by an adaptive randomization procedure. The primary outcome is change in PTSD symptom severity from pre- to post-treatment. The secondary biological outcome is change from pre- to post-treatment in psychophysiological response, startle by electromyographic (EMG) eyeblink. Assessments will be conducted at pre-, mid-, post-, and 1-month post-treatment, blind to group allocation. Intent-to-treat analyses will be conducted. DISCUSSION: The study results will be definitive because both clinical and biological outcomes will be assessed and correlated. Issues such as the number needed for recruitment and improvement, use of sham acupuncture, choice of biological measure, and future research need will be discussed. TRIAL REGISTRATION: ClinicalTrials.gov NCT02869646 . Registered on 17 August 2016.


Asunto(s)
Terapia por Acupuntura , Trastornos por Estrés Postraumático , Veteranos , Terapia por Acupuntura/efectos adversos , Humanos , Estudios Prospectivos , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/terapia , Resultado del Tratamiento
9.
Appl Psychophysiol Biofeedback ; 46(2): 161-173, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33877491

RESUMEN

Research suggest that in autism spectrum disorder (ASD) a disturbance in the coordinated interactions of neurons within local networks gives rise to abnormal patterns of brainwave activity in the gamma bandwidth. Low frequency transcranial magnetic stimulation (TMS) over the dorsolateral prefrontal cortex (DLPFC) has been proven to normalize gamma oscillation abnormalities, executive functions, and repetitive behaviors in high functioning ASD individuals. In this study, gamma frequency oscillations in response to a visual classification task (Kanizsa figures) were analyzed and compared in 19 ASD (ADI-R diagnosed, 14.2 ± 3.61 years old, 5 girls) and 19 (14.8 ± 3.67 years old, 5 girls) age/gender matched neurotypical individuals. The ASD group was treated with low frequency TMS (1.0 Hz, 90% motor threshold, 18 weekly sessions) targeting the DLPFC. In autistic subjects, as compared to neurotypicals, significant differences in event-related gamma oscillations were evident in amplitude (higher) pre-TMS. In addition, recordings after TMS treatment in our autistic subjects revealed a significant reduction in the time period to reach peak amplitude and an increase in the decay phase (settling time). The use of a novel metric for gamma oscillations. i.e., envelope analysis, and measurements of its ringing decay allowed us to characterize the impedance of the originating neuronal circuit. The ringing decay or dampening of gamma oscillations is dependent on the inhibitory tone generated by networks of interneurons. The results suggest that the ringing decay of gamma oscillations may provide a biomarker reflective of the excitatory/inhibitory balance of the cortex and a putative outcome measure for interventions in autism.


Asunto(s)
Trastorno del Espectro Autista , Estimulación Magnética Transcraneal , Adolescente , Trastorno del Espectro Autista/terapia , Niño , Función Ejecutiva , Femenino , Humanos , Modalidades de Fisioterapia , Corteza Prefrontal
10.
Semin Pediatr Neurol ; 35: 100832, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32892959

RESUMEN

Despite growing knowledge about autism spectrum disorder (ASD), research findings have not been translated into curative treatment. At present, most therapeutic interventions provide for symptomatic treatment. Outcomes of interventions are judged by subjective endpoints (eg, behavioral assessments) which alongside the highly heterogeneous nature of ASD account for wide variability in the effectiveness of treatments. Transcranial magnetic stimulation (TMS) is one of the first treatments that targets a putative core pathologic feature of autism, specifically the cortical inhibitory imbalance that alters gamma frequency synchronization. Studies show that low frequency TMS over the dorsolateral prefrontal cortex of individuals with ASD decreases the power of gamma activity and increases the difference between gamma responses to target and nontarget stimuli. TMS improves executive function skills related to self-monitoring behaviors and the ability to apply corrective actions. These improvements manifest themselves as a reduction of stimulus bound behaviors and diminished sympathetic arousal. Results become more significant with increasing number of sessions and bear synergism when used along with neurofeedback. When applied at low frequencies in individuals with ASD, TMS appears to be safe and to improve multiple patient-oriented outcomes. Future studies should be conducted in large populations to establish predictors of outcomes (eg, genetic profiling), length of persistence of benefits, and utility of booster sessions.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Trastorno del Espectro Autista/terapia , Sincronización Cortical , Potenciales Evocados , Función Ejecutiva , Ritmo Gamma , Estimulación Magnética Transcraneal , Adolescente , Adulto , Niño , Sincronización Cortical/fisiología , Potenciales Evocados/fisiología , Función Ejecutiva/fisiología , Ritmo Gamma/fisiología , Humanos , Adulto Joven
11.
Brain Sci ; 10(7)2020 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-32635201

RESUMEN

Autism spectrum disorder (ASD) is a behaviorally diagnosed neurodevelopmental condition of unknown pathology. Research suggests that abnormalities of elecltroencephalogram (EEG) gamma oscillations may provide a biomarker of the condition. In this study, envelope analysis of demodulated waveforms for evoked and induced gamma oscillations in response to Kanizsa figures in an oddball task were analyzed and compared in 19 ASD and 19 age/gender-matched neurotypical children. The ASD group was treated with low frequency transcranial magnetic stimulation (TMS), (1.0 Hz, 90% motor threshold, 18 weekly sessions) targeting the dorsolateral prefrontal cortex. In ASD subjects, as compared to neurotypicals, significant differences in evoked and induced gamma oscillations were evident in higher magnitude of gamma oscillations pre-TMS, especially in response to non-target cues. Recordings post-TMS treatment in ASD revealed a significant reduction of gamma responses to task-irrelevant stimuli. Participants committed fewer errors post-TMS. Behavioral questionnaires showed a decrease in irritability, hyperactivity, and repetitive behavior scores. The use of a novel metric for gamma oscillations. i.e., envelope analysis using wavelet transformation allowed for characterization of the impedance of the originating neuronal circuit. The results suggest that gamma oscillations may provide a biomarker reflective of the excitatory/inhibitory balance of the cortex and a putative outcome measure for interventions in autism.

12.
Psychiatr Clin North Am ; 43(2): 229-248, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32439019

RESUMEN

The presence of heterotopias, increased regional density of neurons at the gray-white matter junction, and focal cortical dysplasias all suggest an abnormality of neuronal migration in autism spectrum disorder (ASD). The abnormality is borne from a dissonance in timing between radial and tangentially migrating neuroblasts to the developing cortical plate. The uncoupling of excitatory and inhibitory cortical cells disturbs the coordinated interactions of neurons within local networks, thus providing abnormal patterns of brainwave activity in the gamma bandwidth. In ASD, gamma oscillation abnormalities and autonomic markers offer measures of therapeutic progress and help in the identification of subgroups.


Asunto(s)
Trastorno del Espectro Autista/terapia , Estimulación Magnética Transcraneal , Trastorno del Espectro Autista/patología , Encéfalo/patología , Niño , Función Ejecutiva , Humanos
13.
Appl Psychophysiol Biofeedback ; 45(2): 87-98, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32277303

RESUMEN

In this paper we discuss the strategies of self-regulation that are used under stressful condition. The strategies were assessed by means of heart rate biofeedback with game plot that models a stressful situation as a sport competition. Special attention was paid to the analysis of personality traits, behavioral patterns, and other psychological correlates of effective learning of self-regulation skills during biofeedback training. It was shown that the training based on biofeedback computer game allows modifying self-regulation strategies of the subjects towards more effective ones. The steadiness of the stress-resilience skills was statistically confirmed. The psychological tolerance of ambiguity was found to be a basic feature of personality that determines the efficiency of self-regulation strategies under stress.


Asunto(s)
Biorretroalimentación Psicológica/fisiología , Frecuencia Cardíaca/fisiología , Personalidad/fisiología , Resiliencia Psicológica , Autocontrol , Estrés Psicológico/fisiopatología , Adulto , Biorretroalimentación Psicológica/métodos , Humanos , Estrés Psicológico/terapia , Terapia Asistida por Computador
14.
CNS Neurosci Ther ; 25(11): 1254-1261, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31228356

RESUMEN

BACKGROUND: Autism spectrum disorder (ASD) is a very complex neurodevelopmental disorder, characterized by social difficulties and stereotypical or repetitive behavior. Some previous studies using low-frequency repetitive transcranial magnetic stimulation (rTMS) have proven of benefit in ASD children. METHODS: In this study, 32 children (26 males and six females) with low-function autism were enrolled, 16 children (three females and 13 males; mean ± SD age: 7.8 ± 2.1 years) received rTMS treatment twice every week, while the remaining 16 children (three females and 13 males; mean ± SD age: 7.2 ± 1.6 years) served as waitlist group. This study investigated the effects of rTMS on brain activity and behavioral response in the autistic children. RESULTS: Peak alpha frequency (PAF) is an electroencephalographic measure of cognitive preparedness and might be a neural marker of cognitive function for the autism. Coherence is one way to assess the brain functional connectivity of ASD children, which has proven abnormal in previous studies. The results showed significant increases in the PAF at the frontal region, the left temporal region, the right temporal region and the occipital region and a significant increase of alpha coherence between the central region and the right temporal region. Autism Behavior Checklist (ABC) scores were also compared before and after receiving rTMS with positive effects shown on behavior. CONCLUSION: These findings supported our hypothesis by demonstration of positive effects of combined rTMS neurotherapy in active treatment group as compared to the waitlist group, as the rTMS group showed significant improvements in behavioral and functional outcomes as compared to the waitlist group.


Asunto(s)
Trastorno del Espectro Autista/psicología , Trastorno del Espectro Autista/terapia , Encéfalo/fisiología , Electroencefalografía/métodos , Estimulación Magnética Transcraneal/métodos , Niño , Preescolar , Femenino , Humanos , Masculino , Proyectos Piloto , Resultado del Tratamiento
15.
Front Syst Neurosci ; 12: 20, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29892214

RESUMEN

There is no accepted pathology to autism spectrum disorders (ASD) but research suggests the presence of an altered excitatory/inhibitory (E/I) bias in the cerebral cortex. Repetitive transcranial magnetic stimulation (rTMS) offers a non-invasive means of modulating the E/I cortical bias with little in terms of side effects. In this study, 124 high functioning ASD children (IQ > 80, <18 years of age) were recruited and assigned using randomization to either a waitlist group or one of three different number of weekly rTMS sessions (i.e., 6, 12, and 18). TMS consisted of trains of 1.0 Hz frequency pulses applied over the dorsolateral prefrontal cortex (DLPFC). The experimental task was a visual oddball with illusory Kanizsa figures. Behavioral response variables included reaction time and error rate along with such neurophysiological indices such as stimulus and response-locked event-related potentials (ERP). One hundred and twelve patients completed the assigned number of TMS sessions. Results showed significant changes from baseline to posttest period in the following measures: motor responses accuracy [lower percentage of committed errors, slower latency of commission errors and restored normative post-error reaction time slowing in both early and later-stage ERP indices, enhanced magnitude of error-related negativity (ERN), improved error monitoring and post-error correction functions]. In addition, screening surveys showed significant reductions in aberrant behavior ratings and in both repetitive and stereotypic behaviors. These differences increased with the total number of treatment sessions. Our results suggest that rTMS, particularly after 18 sessions, facilitates cognitive control, attention and target stimuli recognition by improving discrimination between task-relevant and task-irrelevant illusory figures in an oddball test. The noted improvement in executive functions of behavioral performance monitoring further suggests that TMS has the potential to target core features of ASD.

16.
Appl Psychophysiol Biofeedback ; 43(2): 169-178, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29926265

RESUMEN

Neural networks interaction was studied in healthy men (20-35 years old) who underwent 20 sessions of EEG biofeedback training outside the MRI scanner, with concurrent fMRI-EEG scans at the beginning, middle, and end of the course. The study recruited 35 subjects for EEG biofeedback, but only 18 of them were considered as "successful" in self-regulation of target EEG bands during the whole course of training. Results of fMRI analysis during EEG biofeedback are reported only for these "successful" trainees. The experimental group (N = 23 total, N = 13 "successful") upregulated the power of alpha rhythm, while the control group (N = 12 total, N = 5 "successful") beta rhythm, with the protocol instructions being as for alpha training in both. The acquisition of the stable skills of alpha self-regulation was followed by the weakening of the irrelevant links between the cerebellum and visuospatial network (VSN), as well as between the VSN, the right executive control network (RECN), and the cuneus. It was also found formation of a stable complex based on the interaction of the precuneus, the cuneus, the VSN, and the high level visuospatial network (HVN), along with the strengthening of the interaction of the anterior salience network (ASN) with the precuneus. In the control group, beta enhancement training was accompanied by weakening of interaction between the precuneus and the default mode network, and a decrease in connectivity between the cuneus and the primary visual network (PVN). The differences between the alpha training group and the control group increased successively during training. Alpha training was characterized by a less pronounced interaction of the network formed by the PVN and the HVN, as well as by an increased interaction of the cerebellum with the precuneus and the RECN. The study demonstrated the differences in the structure and interaction of neural networks involved into alpha and beta generating systems forming and functioning, which should be taken into account during planning neurofeedback interventions. Possibility of using fMRI-guided biofeedback organized according to the described neural networks interaction may advance more accurate targeting specific symptoms during neurotherapy.


Asunto(s)
Ritmo alfa/fisiología , Ritmo beta/fisiología , Electroencefalografía , Imagen por Resonancia Magnética/métodos , Red Nerviosa , Neurorretroalimentación/métodos , Adulto , Mapeo Encefálico , Electroencefalografía/métodos , Voluntarios Sanos , Humanos , Masculino
17.
Front Neurosci ; 12: 201, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29713261

RESUMEN

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder which affects the developmental trajectory in several behavioral domains, including impairments of social communication, cognitive and language abilities. Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique, and it was used for modulating the brain disorders. In this paper, we enrolled 13 ASD children (11 males and 2 females; mean ± SD age: 6.5 ± 1.7 years) to participate in our trial. Each patient received 10 treatments over the dorsolateral prefrontal cortex (DLPFC) once every 2 days. Also, we enrolled 13 ASD children (11 males and 2 females; mean ± SD age: 6.3 ± 1.7 years) waiting to receive therapy as controls. A maximum entropy ratio (MER) method was adapted to measure the change of complexity of EEG series. It was found that the MER value significantly increased after tDCS. This study suggests that tDCS may be a helpful tool for the rehabilitation of children with ASD.

18.
Behav Sci (Basel) ; 7(4)2017 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-29144422

RESUMEN

Several studies have shown that children with autism spectrum disorder (ASD) show abnormalities in P3b to targets in standard oddball tasks. The present study employed a three-stimulus visual oddball task with novel distracters that analyzed event-related potentials (ERP) to both target and non-target items at frontal and parietal sites. The task tested the hypothesis that children with autism are abnormally orienting attention to distracters probably due to impaired habituation to novelty. We predicted a lower selectivity in early ERPs to target, frequent non-target, and rare distracters. We also expected delayed late ERPs in autism. The study enrolled 32 ASD and 24 typically developing (TD) children. Reaction time (RT) and accuracy were analyzed as behavioral measures, while ERPs were recorded with a dense-array EEG system. Children with ASD showed higher error rate without normative post-error RT slowing and had lower error-related negativity. Parietal P1, frontal N1, as well as P3a and P3b components were higher to novels in ASD. Augmented exogenous ERPs suggest low selectivity in pre-processing of stimuli resulting in their excessive processing at later stages. The results suggest an impaired habituation to unattended stimuli that incurs a high load at the later stages of perceptual and cognitive processing and response selection when novel distracter stimuli are differentiated from targets.

19.
Sci Rep ; 7(1): 16253, 2017 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-29176705

RESUMEN

Alterations in brain connectivity have been extensively reported in autism spectrum disorder (ASD), while their effects on the topology of brain network are still unclear. This study investigated whether and how the brain networks in children with ASD were abnormally organized with resting state EEG. Temporal synchronization analysis was first applied to capture the aberrant brain connectivity. Then brain network topology was characterized by three graph analysis methods including the commonly-used weighted and binary graph, as well as minimum spanning tree (MST). Whole brain connectivity in ASD group was found to be significantly reduced in theta and alpha band compared to typically development children (TD). Weighted graph found significantly decreased path length together with marginally significantly decreased clustering coefficient in ASD in alpha band, indicating a loss of small-world architecture to a random network. Such abnormal network topology was also demonstrated in the binary graph. In MST analysis, children with ASD showed a significant lower leaf fractions with a decrease trend of tree hierarchy in the alpha band, suggesting a shift towards line-like decentralized organization in ASD. The altered brain network may offer an insight into the underlying pathology of ASD and possibly serve as a biomarker that may aid in diagnosis of ASD.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Encéfalo/fisiopatología , Ritmo alfa , Niño , Sincronización Cortical , Femenino , Humanos , Masculino , Ritmo Teta
20.
Appl Psychophysiol Biofeedback ; 41(4): 405-420, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27573986

RESUMEN

Autism is a pervasive developmental disorder of childhood characterized by deficits in social interaction, language, and stereotyped behaviors along with a restricted range of interests. It is further marked by an inability to perceive and respond to social and emotional signals in a typical manner. This might due to the functional disconnectivity of networks important for specific aspects of social cognition and behavioral control resulting in deficits of sensory information integration. According to several recent theories sensory processing and integration abnormalities may play an important role in impairments of perception, cognition, and behavior in individuals with autism. Among these sensory abnormalities, auditory perception distortion may contribute to many typical symptoms of autism. The present study used Berard's technique of auditory integration training (AIT) to improve sound integration in children with autism. It also aimed to understand the abnormal neural and functional mechanisms underlying sound processing distortion in autism by incorporating behavioral, psychophysiological and neurophysiological outcomes. It was proposed that exposure to twenty 30-min AIT sessions (total 10 h of training) would result in improved behavioral evaluation scores, improve profile of cardiorespiratory activity, and positively affect both early [N1, mismatch negativity (MMN)] and late (P3) components of evoked potentials in auditory oddball task. Eighteen children with autism spectrum disorder (ASD) participated in the study. A group of 16 typically developing children served as a contrast group in the auditory oddball task. Autonomic outcomes of the study reflected a linear increase of heart rate variability measures and respiration rate. Comparison of evoked potential characteristics of children with ASD versus typically developing children revealed several group difference findings, more specifically, a delayed latency of N1 to rare and frequent stimuli, larger MMN; higher P3a to frequent stimuli, and at the same time delayed latency of P3b to rare stimuli in the autism group. Post-AIT changes in evoked potentials could be summarized as a decreased magnitude of N1 to rare stimuli, marginally lower negativity of MMN, and decrease of the P3a to frequent stimuli along with delayed latency and higher amplitude of the P3b to the rare stimuli. These evoked potential changes following completion of Berard AIT course are in a positive direction, making them less distinct from those recorded in age-matched group of typical children, thus could be considered as changes towards normalization. Parental questionnaires clearly demonstrated improvements in behavioral symptoms such as irritability, hyperactivity, repetitive behaviors and other important behavioral domains. The results of the study propose that more controlled research is necessary to document behavioral and psychophysiological changes resulting from Berard AIT and to provide explanation of the neural mechanisms of how auditory integration training may affect behavior and psychophysiological responses of children with ASD.


Asunto(s)
Estimulación Acústica/métodos , Trastorno del Espectro Autista/terapia , Potenciales Evocados/fisiología , Adolescente , Trastorno del Espectro Autista/fisiopatología , Niño , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Tiempo de Reacción/fisiología , Encuestas y Cuestionarios
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