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1.
Epilepsia ; 63(10): 2583-2596, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35778973

RESUMEN

OBJECTIVE: Working memory deficits are prevalent in childhood epilepsy. Working memory processing is thought to be supported by the phase of hippocampal neural oscillations. Disruptions in working memory have previously been linked to the occurrence of transient epileptic activity. This study aimed to resolve the associations between oscillatory neural activity, transient epileptiform events, and working memory in children with epilepsy. METHODS: Intracranial recordings were acquired from stereotactically implanted electrodes in the hippocampi, epileptogenic zones, and working memory-related networks of children with drug-resistant epilepsy during a 1-back working memory task. Interictal epileptic activity was captured using automated detectors. Hippocampal phase and interregional connectivity within working memory networks were indexed by Rayleigh Z and the phase difference derivative, respectively. Trials with and without transient epileptiform events were compared. RESULTS: Twelve children (mean age = 14.3 ± 2.8 years) with drug-resistant epilepsy were included in the study. In the absence of transient epileptic activity, significant delta and theta hippocampal phase resetting occurred in response to working memory stimulus presentation (Rayleigh z-score = 9, Rayleigh z-score = 8). Retrieval trials that were in phase with the preferred phase angle were associated with faster reaction times (p = .01, p = .03). Concurrently, delta and theta coordinated interactions between the hippocampi and working memory-related networks were enhanced (phase difference derivative [PDD] z-scores = 6-11). During retrieval trials with pre-encoding or pre-retrieval transient epileptic activity, phase resetting was attenuated (Rayleigh z-score = 5, Rayleigh z-score = 1), interregional connectivity was altered (PDD z-scores = 1-3), and reaction times were prolonged (p = .01, p = .03). SIGNIFICANCE: This work highlights the role of hippocampal phase in working memory. We observe poststimulus hippocampal phase resetting coincident with enhanced interregional connectivity. The precision of hippocampal phase predicts optimal working memory processing, and transient epileptic activity prolongs working memory processing. These findings can help guide future treatments aimed at restoring memory function in this patient population.


Asunto(s)
Epilepsia Refractaria , Epilepsia , Adolescente , Niño , Hipocampo , Humanos , Trastornos de la Memoria/etiología , Memoria a Corto Plazo
2.
Cereb Cortex ; 32(1): 29-40, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34255825

RESUMEN

The neural mechanisms that underlie selective attention in children are poorly understood. By administering a set-shifting task to children with intracranial electrodes stereotactically implanted within anterior cingulate cortex (ACC) for epilepsy monitoring, we demonstrate that selective attention in a set-shifting task is dependent upon theta-band phase resetting immediately following stimulus onset and that the preferred theta phase angle is predictive of reaction time during attentional shift. We also observe selective enhancement of oscillatory coupling between the ACC and the dorsal attention network and decoupling with the default mode network during task performance. When transient focal epileptic activity occurs around the time of stimulus onset, phase resetting is impaired, connectivity changes with attentional and default mode networks are abolished, and reaction times are prolonged. The results of the present work highlight the fundamental mechanistic role of oscillatory phase in ACC in supporting attentional circuitry and present novel opportunities to remediate attention deficits in children with epilepsy.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Epilepsia , Niño , Giro del Cíngulo , Humanos , Imagen por Resonancia Magnética
3.
Oncologist ; 26(12): e2288-e2296, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34516038

RESUMEN

BACKGROUND: There is limited work on the impact of chemotherapy-induced nausea and vomiting (CINV) on quality of life (QoL) in adriamycin-cyclophosphamide (AC)-treated patients with breast cancer. The objectives of the study were the following: (a) to confirm if symptoms of CINV led to lower QoL during AC; (b) to evaluate the pattern of changes in patients' QoL during multiple cycles of AC; and (c) to assess if the QoL in an earlier cycle affected the QoL in subsequent cycles of AC. MATERIALS AND METHODS: This is a secondary pooled data analysis that included 303 Chinese patients with breast cancer who received 1,177 cycles of adjuvant AC in three prospective antiemetic studies. QoL data were based on Functional Living Index-emesis (FLIE) scored over three to four AC cycles. CINV symptoms assessed included "no significant nausea" (NSN), "significant nausea" (SN), "no vomiting" (NoV), "vomiting" (V), and complete response (CR). RESULTS: Across all AC cycles, the mean scores for the FLIE nausea domain for patients who experienced NSN versus SN were 10.92 versus 53.92, respectively (p < .0001), with lower scores indicating better QoL; the mean scores for the FLIE vomiting domain for patients who experienced NoV versus V were 1.44 versus 19.11, respectively (p < .0001), with similar results across subsequent cycles. Analysis of the effect of the QoL in cycle 1 on the QoL of subsequent cycles revealed the following: for the nausea domain, among patients who had cycle 1 FLIE scores ≥ versus < the mean, the corresponding scores in cycle 2 were 6.87 versus 36.71 (p < .0001); whereas those for cycle 3 were 7.07 versus 36.87 (p < .0001); and those for cycle 4 were 5.92 versus 21.48 (p < .0001). Similar findings were observed for the vomiting domain. Netupitant + palonosetron- or aprepitant/olanzapine-based antiemetics had significantly better QoL outcomes. CONCLUSION: CINV had a significant impact on the QoL of patients with breast cancer treated with AC over multiple cycles. IMPLICATIONS FOR PRACTICE: In this post-hoc analysis of three prospective studies on chemotherapy-induced nausea and vomiting (CINV), quality of life (QoL) using contemporary antiemetic regimens in Chinese breast cancer patients receiving doxorubicin-cyclophosphamide (AC) was evaluated. During the first and subsequent AC cycles, QoL was significantly better for patients who did not experience vomiting or significant nausea. QoL in an earlier cycle affected the QoL in subsequent AC cycles. Furthermore, recent regimens involving olanzapine/aprepitant or netupitant-palonosetron were associated with a positive impact in QoL. Antiemetic guideline-consistent practice and higher clinician awareness of the impact of CINV on QoL can further mitigate the negative effects of CINV on QoL.


Asunto(s)
Antraciclinas , Calidad de Vida , Antraciclinas/efectos adversos , Análisis de Datos , Humanos , Náusea/inducido químicamente , Estudios Prospectivos , Vómitos/inducido químicamente
4.
Hum Brain Mapp ; 42(7): 2099-2114, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33528852

RESUMEN

Autism spectrum disorder (ASD) is characterized by social deficits and atypical facial processing of emotional expressions. The underlying neuropathology of these abnormalities is still unclear. Recent studies implicate cerebellum in emotional processing; other studies show cerebellar abnormalities in ASD. Here, we elucidate the spatiotemporal activation of cerebellar lobules in ASD during emotional processing of happy and angry faces in adolescents with ASD and typically developing (TD) controls. Using magnetoencephalography, we calculated dynamic statistical parametric maps across a period of 500 ms after emotional stimuli onset and determined differences between group activity to happy and angry emotions. Following happy face presentation, adolescents with ASD exhibited only left-hemispheric cerebellar activation in a cluster extending from lobule VI to lobule V (compared to TD controls). Following angry face presentation, adolescents with ASD exhibited only midline cerebellar activation (posterior IX vermis). Our findings indicate an early (125-175 ms) overactivation in cerebellar activity only for happy faces and a later overactivation for both happy (250-450 ms) and angry (250-350 ms) faces in adolescents with ASD. The prioritized hemispheric activity (happy faces) could reflect the promotion of a more flexible and adaptive social behavior, while the latter midline activity (angry faces) may guide conforming behavior.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Mapeo Encefálico , Cerebelo/fisiopatología , Emociones/fisiología , Reconocimiento Facial/fisiología , Magnetoencefalografía , Percepción Social , Adolescente , Cerebelo/diagnóstico por imagen , Niño , Expresión Facial , Femenino , Humanos , Masculino
5.
Hum Brain Mapp ; 42(17): 5747-5760, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34582067

RESUMEN

The ability to effectively and automatically regulate one's response to emotional information is a basic, fundamental skill for social functioning. The neural mechanisms underlying emotion regulation processing have been assessed, however few investigations have leveraged neurophysiological techniques, particularly magnetoencephalography (MEG) to determine the development of this critical ability. The current MEG study is the first to examine developmental changes in the neural mechanisms supporting automatic emotion regulation. We used an emotional go/no-go task with happy and angry faces in a single-site cohort of 97 healthy participants, 4-40 years of age. We found age-related changes as a function of emotion and condition in brain regions key to emotion regulation, including the right inferior frontal gyrus, orbitofrontal cortices and primarily right-lateralized temporal areas. Interaction effects, including an age by emotion and condition, were also found in the left angular gyrus, an area critical in emotion regulation and attention. Findings demonstrate protracted and nonlinear development, due to the adolescent group, of emotion regulation processing from child to adulthood, and highlight that age-related differences in emotion regulation are modulated by emotional face type.


Asunto(s)
Corteza Cerebral/fisiología , Regulación Emocional/fisiología , Función Ejecutiva/fisiología , Desarrollo Humano/fisiología , Inhibición Psicológica , Magnetoencefalografía , Adolescente , Adulto , Niño , Preescolar , Expresión Facial , Reconocimiento Facial/fisiología , Femenino , Humanos , Masculino , Desempeño Psicomotor/fisiología , Adulto Joven
6.
Dev Sci ; 24(1): e12984, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32384181

RESUMEN

As we listen to speech, our ability to understand what was said requires us to retrieve and bind together individual word meanings into a coherent discourse representation. This so-called semantic unification is a fundamental cognitive skill, and its development relies on the integration of neural activity throughout widely distributed functional brain networks. In this proof-of-concept study, we examine, for the first time, how these functional brain networks develop in children. Twenty-six children (ages 4-17) listened to well-formed sentences and sentences containing a semantic violation, while EEG was recorded. Children with stronger vocabulary showed N400 effects that were more concentrated to centroparietal electrodes and greater EEG phase synchrony (phase lag index; PLI) between right centroparietal and bilateral frontocentral electrodes in the delta frequency band (1-3 Hz) 1.27-1.53 s after listening to well-formed sentences compared to sentences containing a semantic violation. These effects related specifically to individual differences in receptive vocabulary, perhaps pointing to greater recruitment of functional brain networks important for top-down semantic unification with development. Less skilled children showed greater delta phase synchrony for violation sentences 3.41-3.64 s after critical word onset. This later effect was partly driven by individual differences in nonverbal reasoning, perhaps pointing to non-verbal compensatory processing to extract meaning from speech in children with less developed vocabulary. We suggest that functional brain network communication, as measured by momentary changes in the phase synchrony of EEG oscillations, develops throughout the school years to support language comprehension in different ways depending on children's verbal and nonverbal skill levels.


Asunto(s)
Semántica , Vocabulario , Adolescente , Niño , Preescolar , Electroencefalografía , Sincronización de Fase en Electroencefalografía , Potenciales Evocados , Femenino , Humanos , Individualidad , Masculino
7.
Hum Brain Mapp ; 41(13): 3794-3806, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32533810

RESUMEN

Very preterm born (VPT) children are those born before 32/40 weeks' gestational age and comprise 10% of the 15 million babies born prematurely worldwide each year. Due to advancements in neonatal medicine, the survival rate of VPT birth has increased, but few studies have investigated the nonmedical, social-cognitive morbidities that affect these children. In this study, we examined emotional face processing networks in VPT compared to age and sex matched full-term born (FT) children. Magnetoencephalography (MEG) was used to test VPT and FT born children at 6 years (n = 78) and 8 years (n = 83). Children were assessed using an implicit emotion face-processing task. Happy, fearful, and angry faces were presented for 150 ms, but children were asked to respond by button press to the location of a control pixelated image of the face displayed on the side of the screen opposite to the face. Children rated the valence of the images on a five-point scale. Group differences showed that VPT children rated angry faces more positively than their FT peers. VPT children had reduced connectivity for angry and fearful faces at 8 years in networks including regions such as the bilateral amygdala, superior temporal sulci, and anterior cingulate gyrus. Interventions should target both emotion recognition, as well as higher cognitive processes related to emotional control and thinking about one's own emotions.


Asunto(s)
Ira/fisiología , Desarrollo Infantil/fisiología , Conectoma , Reconocimiento Facial/fisiología , Miedo/fisiología , Recien Nacido Extremadamente Prematuro/fisiología , Red Nerviosa/fisiopatología , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/fisiopatología , Niño , Expresión Facial , Femenino , Giro del Cíngulo/diagnóstico por imagen , Giro del Cíngulo/fisiopatología , Humanos , Recién Nacido , Magnetoencefalografía , Masculino , Red Nerviosa/diagnóstico por imagen , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiopatología
8.
Ann Neurol ; 86(5): 743-753, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31393626

RESUMEN

OBJECTIVE: Vagus nerve stimulation (VNS) is a common treatment for medically intractable epilepsy, but response rates are highly variable, with no preoperative means of identifying good candidates. This study aimed to predict VNS response using structural and functional connectomic profiling. METHODS: Fifty-six children, comprising discovery (n = 38) and validation (n = 18) cohorts, were recruited from 3 separate institutions. Diffusion tensor imaging was used to identify group differences in white matter microstructure, which in turn informed beamforming of resting-state magnetoencephalography recordings. The results were used to generate a support vector machine learning classifier, which was independently validated. This algorithm was compared to a second classifier generated using 31 clinical covariates. RESULTS: Treatment responders demonstrated greater fractional anisotropy in left thalamocortical, limbic, and association fibers, as well as greater connectivity in a functional network encompassing left thalamic, insular, and temporal nodes (p < 0.05). The resulting classifier demonstrated 89.5% accuracy and area under the receiver operating characteristic (ROC) curve of 0.93 on 10-fold cross-validation. In the external validation cohort, this model demonstrated an accuracy of 83.3%, with a sensitivity of 85.7% and specificity of 75.0%. This was significantly superior to predictions using clinical covariates alone, which exhibited an area under the ROC curve of 0.57 (p < 0.008). INTERPRETATION: This study provides the first multi-institutional, multimodal connectomic prediction algorithm for VNS, and provides new insights into its mechanism of action. Reliable identification of VNS responders is critical to mitigate surgical risks for children who may not benefit, and to ensure cost-effective allocation of health care resources. ANN NEUROL 2019;86:743-753.


Asunto(s)
Conectoma/métodos , Epilepsia Refractaria/fisiopatología , Epilepsia Refractaria/terapia , Máquina de Vectores de Soporte , Resultado del Tratamiento , Estimulación del Nervio Vago/métodos , Adolescente , Niño , Preescolar , Imagen de Difusión Tensora/métodos , Epilepsia Refractaria/diagnóstico por imagen , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Magnetoencefalografía/métodos , Masculino , Selección de Paciente
9.
Epilepsia ; 61(8): 1691-1700, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32619065

RESUMEN

OBJECTIVE: Seizure recurrence following surgery for temporal lobe (TL) epilepsy may be related to extratemporal epileptogenic foci, so-called temporal-plus (TL+) epilepsy. Here, we sought to leverage whole brain connectomic profiling in magnetoencephalography (MEG) to identify neural networks indicative of TL+ epilepsy in children. METHODS: Clinical and MEG data were analyzed for 121 children with TL and TL+ epilepsy spanning 20 years at the Hospital for Sick Children. Resting-state connectomes were derived using the weighted phase lag index from neuromagnetic oscillations. Multidimensional associations between patient connectomes, TL versus TL+ epilepsy, seizure freedom, and clinical covariates were performed using a partial least squares (PLS) analysis. Bootstrap resampling statistics were performed to assess statistical significance. RESULTS: A single significant latent variable representing 66% of the variance in the data was identified with significant contributions from extent of epilepsy (TL vs TL+), duration of illness, and underlying etiology. This component was associated with significant bitemporal and frontotemporal connectivity in the theta, alpha, and beta bands. By extracting a brain score, representative of the observed connectivity profile, patients with TL epilepsy were dissociated from those with TL+, independent of their postoperative seizure outcome. SIGNIFICANCE: By analyzing 121 connectomes derived from MEG data using a PLS approach, we find that connectomic profiling could dissociate TL from TL+ epilepsy. These findings may inform patient selection for resective procedures and guide decisions surrounding invasive monitoring.


Asunto(s)
Conectoma , Epilepsia Refractaria/fisiopatología , Epilepsia del Lóbulo Temporal/fisiopatología , Magnetoencefalografía , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Epilepsia Refractaria/cirugía , Epilepsia del Lóbulo Temporal/cirugía , Femenino , Humanos , Análisis de los Mínimos Cuadrados , Masculino , Vías Nerviosas/fisiopatología , Procedimientos Neuroquirúrgicos , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento
10.
Health Qual Life Outcomes ; 18(1): 24, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-32041627

RESUMEN

INTRODUCTIONS: For young premenopausal breast cancer patients, adjuvant chemotherapy may cause menstrual disruptions and premature menopause, which may in turn impair their quality of life (QoL). In this study among young breast cancer survivors who have undergone adjuvant chemotherapy, the objectives were to assess post-treatment menopausal symptoms and their associated factors, and to correlate these symptoms with breast cancer-specific QoL. METHODS: The study population included premenopausal young Chinese women with early-stage breast cancer who had undergone adjuvant chemotherapy between 3 and 10 years prior to enrolling into this study. At study entry, patients' characteristics and clinical features were collected; each patient had detail menstrual history collected and each filled in MENQOL and FACT-B + 4 questionnaires. RESULTS: Two hundred eighty eligible patients were recruited. For adjuvant chemotherapy, 92% received anthracyclines and 28% received taxanes; 76% received adjuvant tamoxifen. At a median of 5.0 years from initial cancer diagnosis, 49 and 11% had become post- and peri-menopausal respectively. MENQOL at study entry revealed that physical domain score was worse in overweight/obese patients (mean scores for underweight/normal vs overweight/obese: 2.65 vs 2.97, p = 0.0162). Vasomotor domain score was worse in those who received taxanes or tamoxifen (taxane vs non-taxane: 2.91 vs. 2.35, p = 0.0140; tamoxifen vs no tamoxifen: 2.75 vs. 2.34, p = 0.0479). Sexual domain score was worse among those who had become peri/post-menopausal (peri/postmenopausal vs premenopausal: 2.82 vs. 2.29, p = 0.0229). On the other hand, patients who utilized traditional Chinese medicine had significantly worse scores for vasomotor, psychosocial and physical domains. Further, there was a significant association between MENQOL scores and FACT-B + 4 scores; less severe symptoms in the MENQOL domains were associated with better QoL scores in FACT-B + 4 physical, functional, psychosocial and emotional well-being, Breast Cancer Subscale, Arm Subscale and FACT-B total score. CONCLUSION: Among premenopausal breast cancer women who had undergone adjuvant chemotherapy, those who had received taxanes or tamoxifen, were overweight/obese and utilized traditional Chinese medicine had more severe menopausal symptoms. Patients who experienced worse menopausal symptoms were found to have worse breast cancer-specific QoL. Interventional studies with an aim to alleviate menopausal symptoms are warranted to assess if overall QoL of these patients could be improved. TRIAL REGISTRATION: Not applicable.


Asunto(s)
Antineoplásicos/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Supervivientes de Cáncer/psicología , Menopausia/psicología , Calidad de Vida/psicología , Adulto , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/psicología , Quimioterapia Adyuvante/efectos adversos , Estudios Transversales , Femenino , Humanos , Medicina Tradicional China/efectos adversos , Persona de Mediana Edad , Obesidad/inducido químicamente , Obesidad/psicología
11.
Hum Brain Mapp ; 39(7): 2907-2916, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29573366

RESUMEN

Emotion regulation mediates socio-cognitive functions and is essential for interactions with others. The capacity to automatically inhibit responses to emotional stimuli is an important aspect of emotion regulation; the underlying neural mechanisms of this ability have been rarely investigated. Forty adults completed a Go/No-go task during magnetoencephalographic (MEG) recordings, where they responded rapidly to either a blue or purple frame which contained angry or happy faces. Subjects responded to the target color in an inhibition (75% Go trials) and a vigilance condition (25% Go trials). As expected, inhibition processes showed early, sustained activation (200-450 ms) in the right inferior frontal gyrus (IFG). Emotion-related inhibition processes showed greater activity with angry faces bilaterally in the orbital-frontal gyri (OFG) starting at 225 ms and temporal poles from 250 ms, with right hemisphere dominance. The presence of happy faces elicited earlier activity in the right OFG. This study demonstrates that the timing of inhibition processes varies with the emotional context and that there is much greater activation in the presence of angry faces. It underscores the importance of the right IFG for inhibition processes, but the OFG in automatic emotion regulation.


Asunto(s)
Emociones/fisiología , Función Ejecutiva/fisiología , Reconocimiento Facial/fisiología , Neuroimagen Funcional/métodos , Inhibición Psicológica , Magnetoencefalografía/métodos , Corteza Prefrontal/fisiología , Autocontrol , Percepción Social , Adulto , Femenino , Humanos , Masculino , Corteza Prefrontal/diagnóstico por imagen , Adulto Joven
12.
Brain Cogn ; 120: 58-66, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29065995

RESUMEN

Mental flexibility is a core property of cognitive executive functions, relying on an extended frontoparietal network in the brain. fMRI research comparing typically developing children and adults has found that children from an early age recruit the same "classic" brain areas associated with mental flexibility as adults; however, there is evidence that the timing of activation may be different. To investigate the temporal dynamics of brain activity associated with mental flexibility in children, we recruited 22 typically developing children (8-15 years) to complete a set-shifting task in the MEG. Our results showed that while the children relied on the same frontoparietal network of mental flexibility, there was a different emphasis on active brain regions, with children preferentially using their posterior parietal cortices. Additional areas such as the temporal pole and the premotor areas were also recruited, potentially playing a supporting role. Although children shared the same window of peak activity as adults, 75-350ms, we found a significant decrease in activation latency with increasing age, suggesting the presence of developmental differences in timing of brain activity in areas supporting mental flexibility during childhood.


Asunto(s)
Mapeo Encefálico/métodos , Desarrollo Infantil/fisiología , Función Ejecutiva/fisiología , Magnetoencefalografía/métodos , Lóbulo Parietal/fisiología , Desempeño Psicomotor/fisiología , Adolescente , Niño , Femenino , Humanos , Masculino
13.
J Neurosci ; 36(2): 419-31, 2016 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-26758834

RESUMEN

Post-traumatic stress disorder (PTSD) is an anxiety disorder arising from exposure to a traumatic event. Although primarily defined in terms of behavioral symptoms, the global neurophysiological effects of traumatic stress are increasingly recognized as a critical facet of the human PTSD phenotype. Here we use magnetoencephalographic recordings to investigate two aspects of information processing: inter-regional communication (measured by functional connectivity) and the dynamic range of neural activity (measured in terms of local signal variability). We find that both measures differentiate soldiers diagnosed with PTSD from soldiers without PTSD, from healthy civilians, and from civilians with mild traumatic brain injury, which is commonly comorbid with PTSD. Specifically, soldiers with PTSD display inter-regional hypersynchrony at high frequencies (80-150 Hz), as well as a concomitant decrease in signal variability. The two patterns are spatially correlated and most pronounced in a left temporal subnetwork, including the hippocampus and amygdala. We hypothesize that the observed hypersynchrony may effectively constrain the expression of local dynamics, resulting in less variable activity and a reduced dynamic repertoire. Thus, the re-experiencing phenomena and affective sequelae in combat-related PTSD may result from functional networks becoming "stuck" in configurations reflecting memories, emotions, and thoughts originating from the traumatizing experience. SIGNIFICANCE STATEMENT: The present study investigates the effects of post-traumatic stress disorder (PTSD) in combat-exposed soldiers. We find that soldiers with PTSD exhibit hypersynchrony in a circuit of temporal lobe areas associated with learning and memory function. This rigid functional architecture is associated with a decrease in signal variability in the same areas, suggesting that the observed hypersynchrony may constrain the expression of local dynamics, resulting in a reduced dynamic range. Our findings suggest that the re-experiencing of traumatic events in PTSD may result from functional networks becoming locked in configurations that reflect memories, emotions, and thoughts associated with the traumatic experience.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiopatología , Dinámicas no Lineales , Trastornos por Estrés Postraumático/patología , Adulto , Algoritmos , Relojes Biológicos , Estudios de Casos y Controles , Entropía , Humanos , Magnetoencefalografía , Masculino , Personal Militar , Análisis Espectral
14.
Hum Brain Mapp ; 38(11): 5577-5589, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28766907

RESUMEN

Very preterm (VPT) birth (<32 weeks' gestational age) has been implicated in social-cognitive deficits including Theory of Mind (ToM); the ability to attribute mental states to others and understand that those beliefs can differ from one's own or reality. The neural bases for ToM deficits in VPT born children have not been examined. We used magnetoencephalography (MEG) for its excellent spatial and temporal resolution to determine the neural underpinnings of ToM in 24 VPT and 24 full-term born (FT) children (7-13 years). VPT children performed more poorly on neuropsychological measures of ToM but not inhibition. In the MEG task, both FT children and VPT children recruited regions involved in false belief processing such as the rIFG (VPT: 275-350 ms, FT: 250-375 ms) and left inferior temporal gyrus (VPT: 375-450 ms, FT: 325-375 ms) and right fusiform gyrus (VPT: 150-200 ms, FT: 175-250 ms). The rIPL (included in the temporal-parietal junction) was recruited in FT children (475-575 ms) and the lTPJ in VPT children (500-575 ms). However, activations in all regions were reduced in the VPT compared to the FT group. We suggest that with increasing social-cognitive demands such as varying the type of scenarios in the standardized measure of ToM, reduced activations in the rIFG and TPJ in the VPT group may reflect the decreased performance. With access to both spatial and temporal information, we discuss the role of domain general and specific regions of the ToM network in both groups. Hum Brain Mapp 38:5577-5589, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Encéfalo/fisiología , Recien Nacido Prematuro , Magnetoencefalografía , Teoría de la Mente/fisiología , Adolescente , Niño , Femenino , Humanos , Recien Nacido Prematuro/fisiología , Recien Nacido Prematuro/psicología , Inhibición Psicológica , Masculino , Pruebas Neuropsicológicas
15.
PLoS Comput Biol ; 12(12): e1004914, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27906973

RESUMEN

Accurate means to detect mild traumatic brain injury (mTBI) using objective and quantitative measures remain elusive. Conventional imaging typically detects no abnormalities despite post-concussive symptoms. In the present study, we recorded resting state magnetoencephalograms (MEG) from adults with mTBI and controls. Atlas-guided reconstruction of resting state activity was performed for 90 cortical and subcortical regions, and calculation of inter-regional oscillatory phase synchrony at various frequencies was performed. We demonstrate that mTBI is associated with reduced network connectivity in the delta and gamma frequency range (>30 Hz), together with increased connectivity in the slower alpha band (8-12 Hz). A similar temporal pattern was associated with correlations between network connectivity and the length of time between the injury and the MEG scan. Using such resting state MEG network synchrony we were able to detect mTBI with 88% accuracy. Classification confidence was also correlated with clinical symptom severity scores. These results provide the first evidence that imaging of MEG network connectivity, in combination with machine learning, has the potential to accurately detect and determine the severity of mTBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Magnetoencefalografía/métodos , Procesamiento de Señales Asistido por Computador , Adulto , Encéfalo/fisiopatología , Lesiones Traumáticas del Encéfalo/fisiopatología , Análisis por Conglomerados , Humanos , Masculino , Adulto Joven
16.
BMC Womens Health ; 17(1): 55, 2017 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-28750616

RESUMEN

BACKGROUND: Adjuvant chemotherapy improves outcome of patients with early breast cancer. However, chemotherapy may be associated with long term toxicities. In this retrospective cohort study, the objectives were to determine body weight, body mass index (BMI), blood pressure and fasting lipids levels of young premenopausal Chinese breast cancer patients after adjuvant chemotherapy. Potential factors associated with these parameters were identified. METHODS: Eligibility criteria include premenopausal Chinese patients who were diagnosed to have stage I-III breast cancer within 3-10 years, age < 45 and having received adjuvant chemotherapy at the time of breast cancer diagnosis. Information at initial breast cancer diagnosis were retrieved from patients' medical records and include age at diagnosis, tumor characteristics, anti-cancer treatments, blood pressure and body weight and height. At study entry, all patients had additional background demographics collected, as well as blood pressure, body weight and fasting serum lipid profiles measured. Incidence of chemotherapy-related amenorrhoea (CRA) and menopause were determined. Factors associated with weight gain, hypertension and dyslipidaemias were analyzed. RESULTS: Two hundred and eighty patients were studied. The median age at breast cancer diagnosis was 41 years (range: 24-45). The median time from breast cancer diagnosis to study entry was 5.0 years. The median age at study entry was 46.5 years (range: 28-54). 91.1% developed CRA; 48.9% had become menopausal and 10% were peri-menopausal. Between initial breast cancer diagnosis and the time of study entry, the median weight gain was 1.8 kg; 63.2% gained weight by >2%; 52.1% were overweight/obese; 30.7% had hypertension. Abnormal total-cholesterol and LDL-cholesterol occurred in 34.3% and 56.1% respectively. On multivariate analyses, older age was associated with reduced risk while occurrence of CRA and having received taxane-containing regimens were associated with increased risk of weight gain. Oestrogen-receptor positivity was associated with reduced risk while overweight/obese statuses were associated with increased risk of hypertension. Use of tamoxifen was associated with reduced risk of abnormal LDL-cholesterol. Weight gain, overweight/obese, older age, progression to post/peri-menopausal status at study entry, having received corticosteroid premedication before adjuvant chemotherapy and having received taxane-containing adjuvant chemotherapy were associated with increased risk of dyslipidaemias. CONCLUSION: Among young premenopausal Chinese breast cancer patients who had received adjuvant chemotherapy, the current study has revealed that although there was only a median weight gain of 1.8 kg, there was a nearly 60% increase in abnormal BMI. Further, a significant proportion of patients were detected to have hypertension and dyslipidaemias. Interventional studies with lifestyle modifications are warranted.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante/efectos adversos , Lípidos/sangre , Premenopausia , Aumento de Peso/efectos de los fármacos , Adulto , Antineoplásicos/efectos adversos , Índice de Masa Corporal , Neoplasias de la Mama/sangre , Neoplasias de la Mama/fisiopatología , Hidrocarburos Aromáticos con Puentes/efectos adversos , Quimioterapia Adyuvante/métodos , China , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Tamoxifeno/efectos adversos , Taxoides/efectos adversos , Adulto Joven
17.
J Cogn Neurosci ; 28(1): 55-68, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26401810

RESUMEN

Synchronization of oscillations among brain areas is understood to mediate network communication supporting cognition, perception, and language. How task-dependent synchronization during word production develops throughout childhood and adolescence, as well as how such network coherence is related to the development of language abilities, remains poorly understood. To address this, we recorded magnetoencephalography while 73 participants aged 4-18 years performed a verb generation task. Atlas-guided source reconstruction was performed, and phase synchronization among regions was calculated. Task-dependent increases in synchronization were observed in the theta, alpha, and beta frequency ranges, and network synchronization differences were observed between age groups. Task-dependent synchronization was strongest in the theta band, as were differences between age groups. Network topologies were calculated for brain regions associated with verb generation and were significantly associated with both age and language abilities. These findings establish the maturational trajectory of network synchronization underlying expressive language abilities throughout childhood and adolescence and provide the first evidence for an association between large-scale neurophysiological network synchronization and individual differences in the development of language abilities.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Desarrollo del Lenguaje , Lenguaje , Vías Nerviosas/fisiología , Conducta Verbal/fisiología , Adolescente , Factores de Edad , Encéfalo/irrigación sanguínea , Niño , Preescolar , Femenino , Lateralidad Funcional/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Vías Nerviosas/irrigación sanguínea , Oxígeno/sangre , Psicometría , Adulto Joven
18.
Stroke ; 47(10): 2503-10, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27531345

RESUMEN

BACKGROUND AND PURPOSE: Neurocognitive deficits are common among survivors of aneurysmal subarachnoid hemorrhage, even among those with good outcomes and no structural lesions. This study aims to probe the neurophysiological underpinnings of cognitive dysfunction among patients with ruptured intracranial aneurysms using magnetoencephalography (MEG). METHODS: Thirteen patients who had undergone uncomplicated coiling for aneurysmal subarachnoid hemorrhage and 13 matched controls were enrolled. Neuropsychological tests were done before magnetoencephalography scans. Magnetoencephalography data were acquired in a 151-channel, whole-head magnetoencephalography system for resting state and 2 cognitive tasks (go-no-go and set-shifting). Mean time from treatment to test was 18.8 months. RESULTS: Cognitive tasks of inhibition (go-no-go) indicated greater activation in the right anterior cingulate and inferior frontal gyrus, and cognitive set-shifting tasks (mental flexibility) indicated greater activity in the bilateral anterior cingulate cortex and right medial frontal gyrus among aneurysmal subarachnoid hemorrhage patients, with significantly different timing of activation between groups. Resting-state, beta-band connectivity of the anterior cingulate correlated negatively with Montreal Cognitive Assessment scores (left: r=-0.56; P<0.01 and right: r=-0.55; P<0.01): higher connectivity of this region was linked to poorer cognitive test performance. CONCLUSIONS: We have shown increased activation in areas of the anterior cingulate gyrus and frontobasal regions during the execution of more demanding tasks in good grade. The degree of activation in the anterior cingulate gyrus has a negative correlation with cognitive (Montreal Cognitive Assessment) scores. These subtle differences may be related to the common neurocognitive and behavioral complaints seen in this patient population.


Asunto(s)
Encéfalo/diagnóstico por imagen , Cognición/fisiología , Disfunción Cognitiva/diagnóstico por imagen , Hemorragia Subaracnoidea/diagnóstico por imagen , Adulto , Anciano , Disfunción Cognitiva/etiología , Disfunción Cognitiva/psicología , Femenino , Humanos , Magnetoencefalografía , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Disposición en Psicología , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/psicología
19.
Neuroimage ; 134: 320-327, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27039146

RESUMEN

Theory of Mind (ToM) is the ability to understand the perspectives, mental states and beliefs of others in order to anticipate their behaviour and is therefore crucial to social interactions. Although fMRI has been widely used to establish the neural networks implicated in ToM, little is known about the timing of ToM-related brain activity. We used magnetoencephalography (MEG) to measure the neural processes underlying ToM, as MEG provides very accurate timing and excellent spatial localization of brain processes. We recorded MEG activity during a false belief task, a reliable measure of ToM, in twenty young adults (10 females). MEG data were recorded in a 151 sensor CTF system (MISL, Coquitlam, BC) and data were co-registered to each participant's MRI (Siemens 3T) for source reconstruction. We found stronger right temporoparietal junction (rTPJ) activations in the false belief condition from 150ms to 225ms, in the right precuneus from 275ms to 375ms, in the right inferior frontal gyrus from 200ms to 300ms and the superior frontal gyrus from 300ms to 400ms. Our findings extend the literature by demonstrating the timing and duration of neural activity in the main regions involved in the "mentalizing" network, showing that activations related to false belief in adults are predominantly right lateralized and onset around 100ms. The sensitivity of MEG will allow us to determine spatial and temporal differences in the brain processes in ToM in younger populations or those who demonstrate deficits in this ability.


Asunto(s)
Cultura , Relaciones Interpersonales , Lóbulo Parietal/fisiología , Tiempo de Reacción/fisiología , Lóbulo Temporal/fisiología , Teoría de la Mente/fisiología , Pensamiento/fisiología , Mapeo Encefálico , Femenino , Humanos , Masculino , Red Nerviosa/fisiología , Análisis Espacio-Temporal , Adulto Joven
20.
Hum Brain Mapp ; 37(1): 153-64, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26485059

RESUMEN

BACKGROUND: Mounting evidence suggests that autism is a network disorder, characterized by atypical brain connectivity, especially in the context of high level cognitive processes such as working memory (WM). Accordingly, atypical WM processes have been related to the social and cognitive deficits observed in children with autism spectrum disorder (ASD). METHODS: We used magnetoencephalography (MEG) to investigate connectivity differences during a high memory load (2-back) WM task between 17 children with ASD and 20 age-, sex-, and IQ-matched controls. RESULTS: We identified reduced inter-regional alpha-band (9-15 Hz) phase synchronization in children with ASD during the WM task. Reduced WM-related brain synchronization encompassed fronto-temporal networks (ps < 0.04 corrected) previously associated with challenging high-level conditions (i.e. the left insula and the anterior cingulate cortex (ACC)) and memory encoding and/or recognition (i.e. the right middle temporal gyrus and the right fusiform gyrus). Additionally, we found that reduced connectivity processes related to the right fusiform were correlated with the severity of symptoms in children with ASD, suggesting that such atypicalities could be directly related to the behavioural deficits observed. DISCUSSION: This study provides new evidence of atypical long-range synchronization in children with ASD in fronto-temporal areas that crucially contribute to challenging WM tasks, but also emotion regulation and social cognition processes. Thus, these results support the network disorder hypothesis of ASD and argue for a specific pathophysiological contribution of brain processes related to working memory and executive functions on the symptomatology of autism.


Asunto(s)
Trastorno Autístico/complicaciones , Trastorno Autístico/patología , Lóbulo Frontal/fisiopatología , Trastornos de la Memoria/etiología , Memoria a Corto Plazo/fisiología , Red Nerviosa/fisiopatología , Lóbulo Temporal/fisiopatología , Adolescente , Ritmo alfa/fisiología , Estudios de Casos y Controles , Niño , Electroencefalografía , Femenino , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Psicofísica , Estadística como Asunto
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