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1.
Neurology ; 102(12): e209448, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38810172

ABSTRACT

BACKGROUND AND OBJECTIVES: Neurodevelopmental effects of fetal antiseizure medication (ASM) exposure on creativity and executive functions are poorly understood. We previously found fetal valproate exposure to adversely affect measures of creativity and executive functions. In this study, we examine fetal exposure of newer ASMs on these functions in children of women with epilepsy (WWE) compared with children of healthy women (HW). METHODS: The Maternal Outcomes and Neurodevelopmental Effects of Antiepileptic Drugs study is a multicenter NIH-funded prospective observational cohort study of WWE and HW enrolled in pregnancy and their offsprings. This report examines blindly assessed creativity and executive functions in 4.5-year-old children of WWE vs HW. In addition, exposure-dependent ASM effects during the third trimester were examined in children of WWE, using a ratio of maximum observed ASM concentrations and ratio of defined daily dose (ratio DDD). For polytherapy, ratios were summed across ASMs. Linear regression models adjusted for multiple potential confounding factors were conducted for all analyses. The primary outcome for 4.5-year-old children was the Torrance Test of Creative Thinking-Figural Creativity Index. Secondary outcomes included the Global Executive Composite Score from the Behavior Rating Inventory of Executive Function-Preschool Version and subscales and other indexes of both measures. RESULTS: The primary analysis included 251 children of WWE and 73 of HW. No differences in creativity or executive function were found between children of WWE vs HW. No ASM exposure-dependent effects were found for the creativity measures, but exposure-dependent effects for executive function were present for ratio ASM concentration and ratio DDD. DISCUSSION: Our findings at 4.5 years show no differences in creative thinking between children of WWE vs HW (-3.2 [-9.0 to 2.7], p = 0.286) or associations with fetal exposure to ASMs (-2.6 [-11.0 to 5.7], p = 0.530). Secondary analyses revealed fetal exposure-dependent effects for executive function in children of WWE (7.0 [2.9-11.2], p = 0.001), which are most marked for levetiracetam (12.9 [4.2-21.6], p = 0.004). Our findings suggest that even for relatively safe ASMs, dosing needs to be adjusted to concentrations that prevent seizures, but balance risks to the fetus that high concentrations may pose. TRIAL REGISTRATION INFORMATION: The study is registered at ClinicalTrials.gov as NCT01730170.


Subject(s)
Anticonvulsants , Creativity , Epilepsy , Executive Function , Prenatal Exposure Delayed Effects , Humans , Female , Anticonvulsants/adverse effects , Anticonvulsants/therapeutic use , Prenatal Exposure Delayed Effects/chemically induced , Child, Preschool , Pregnancy , Executive Function/drug effects , Male , Epilepsy/drug therapy , Prospective Studies , Adult
2.
JAMA Neurol ; 81(1): 19-29, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37983058

ABSTRACT

Importance: The association of fetal exposure to antiseizure medications (ASMs) with outcomes in childhood are not well delineated. Objective: To examine the association of fetal ASM exposure with subsequent adaptive, behavioral or emotional, and neurodevelopmental disorder outcomes at 2, 3, and 4.5 years of age. Design, Setting, and Participants: The Maternal Outcomes and Neurodevelopmental Effects of Antiepileptic Drugs (MONEAD) study is a prospective, observational cohort study conducted at 20 epilepsy centers in the US. A total of 456 pregnant women with epilepsy or without epilepsy were enrolled from December 19, 2012, to January 13, 2016. Children of enrolled women were followed up with formal assessments at 2, 3, 4.5, and 6 years of age. Statistical analysis took place from August 2022 to May 2023. Exposures: Exposures included mother's epilepsy status as well as mother's ASM blood concentration in the third trimester (for children of women with epilepsy). Women with epilepsy were enrolled regardless of ASM regimen. Main Outcomes and Measures: The primary outcome was the Adaptive Behavior Assessment System, Third Edition (ABAS-3) General Adaptive Composite (GAC) score among children at 4.5 years of age. Children of women with epilepsy and children of women without epilepsy were compared, and the associations of ASM exposures with outcomes among exposed children were assessed. Secondary outcomes involved similar analyses of other related measures. Results: Primary analysis included 302 children of women with epilepsy (143 boys [47.4%]) and 84 children of women without epilepsy (45 boys [53.6%]). Overall adaptive functioning (ABAS-3 GAC score at 4.5 years) did not significantly differ between children of women with epilepsy and children of women without epilepsy (parameter estimate [PE], 0.4 [95% CI, -2.5 to 3.4]; P = .77). However, in adjusted analyses, a significant decrease in functioning was seen with increasing third-trimester maximum ASM blood concentrations (PE, -7.8 [95% CI, -12.6 to -3.1]; P = .001). This decrease in functioning was evident for levetiracetam (PE, -18.9 [95% CI, -26.8 to -10.9]; P < .001) and lamotrigine (PE, -12.0 [95% CI, -23.7 to -0.3]; P = .04), the ASMs with sample sizes large enough for analysis. Results were similar with third-trimester maximum daily dose. Conclusions and Relevance: This study suggests that adaptive functioning of children of women with epilepsy taking commonly used ASMs did not significantly differ from that of children of women without epilepsy, but there was an exposure-dependent association of ASMs with functioning. Thus, psychiatric or psychological screening and referral of women with epilepsy and their offspring are recommended when appropriate. Additional research is needed to confirm these findings.


Subject(s)
Epilepsy , Neurodevelopmental Disorders , Prenatal Exposure Delayed Effects , Child , Male , Female , Humans , Pregnancy , Prospective Studies , Prenatal Exposure Delayed Effects/chemically induced , Prenatal Exposure Delayed Effects/epidemiology , Epilepsy/drug therapy , Anticonvulsants/adverse effects , Neurodevelopmental Disorders/epidemiology , Neurodevelopmental Disorders/etiology
3.
Lancet Neurol ; 22(8): 712-722, 2023 08.
Article in English | MEDLINE | ID: mdl-37479375

ABSTRACT

BACKGROUND: The neurodevelopmental effects of fetal exposure to most antiseizure medications are unclear. We aimed to investigate the effects of fetal exposure to commonly used antiseizure medications on neuropsychological outcomes at age 3 years. METHODS: The Maternal Outcomes and Neurodevelopmental Effects of Antiepileptic Drugs (MONEAD) study is a prospective, observational, multicentre cohort study at 20 specialty epilepsy centres in the USA. We have investigated pregnancy outcomes in women (aged 14-45 years) with and without epilepsy who were enrolled during pregnancy (≤20 weeks' gestational age), and their children. The primary outcome for children at age 3 years was a blindly assessed Verbal Index score, which was calculated by averaging scores on the Naming Vocabulary and Verbal Comprehension subtests of Differential Ability Scales-II, Expressive Communication and Auditory Comprehension subscales of Preschool Language Scale-5, and Peabody Picture Vocabulary Test-4. Children of women with and without epilepsy were compared, and the associations of medication exposures to outcomes in exposed children were assessed. The MONEAD study is registered with ClinicalTrials.gov, NCT0730170, and is ongoing. FINDINGS: Between Dec 19, 2012, and Jan 13, 2016, 456 pregnant women (351 with epilepsy and 105 without epilepsy) were enrolled into the study. 345 children were born to women with epilepsy and 106 children were born to women without epilepsy. Verbal Index scores at age 3 years did not differ for children of women with epilepsy (n=284; adjusted least-square mean 102·7, 95% CI 101·4 to 103·9) versus those without epilepsy (n=87; 102·3, 99·8 to 104·7). Significant risk factors for reduced Verbal Index scores included maternal intelligence quotient, maternal education, post-birth anxiety, gestational age at enrolment, child's sex, and child's ethnicity. For Verbal Index scores, antiseizure medication exposure effects were not seen for maximum third trimester blood concentrations (n=258; adjusted parameter estimate -2·9, 95% CI -6·7 to 1·0). However, in secondary analyses, exposure-dependent effects were present on multiple cognitive measures, which varied by medication. INTERPRETATION: We found no difference in neurodevelopmental outcomes between children with fetal exposure to newer antiseizure medications compared with unexposed children. However, some exposure-dependent antiseizure medication effects were seen in secondary analyses. The adverse effects of maternal post-birth anxiety emphasise the importance of screening mothers during pregnancy and postpartum and implementing interventions. Additional studies are needed to clarify the exposure-dependent effects. FUNDING: National Institutes of Health, National Institute of Neurological Disorders and Stroke, and National Institute of Child Health and Development.


Subject(s)
Epilepsy , Prenatal Exposure Delayed Effects , Child, Preschool , Child , Humans , Female , Pregnancy , Anticonvulsants/adverse effects , Cohort Studies , Prospective Studies , Epilepsy/drug therapy , Cognition , Prenatal Exposure Delayed Effects/chemically induced , Prenatal Exposure Delayed Effects/drug therapy
4.
JAMA Neurol ; 78(8): 927-936, 2021 08 01.
Article in English | MEDLINE | ID: mdl-34096986

ABSTRACT

Importance: The neurodevelopmental risks of fetal exposure are uncertain for many antiseizure medications (ASMs). Objective: To compare children at 2 years of age who were born to women with epilepsy (WWE) vs healthy women and assess the association of maximum ASM exposure in the third trimester and subsequent cognitive abilities among children of WWE. Design, Setting, and Participants: The Maternal Outcomes and Neurodevelopmental Effects of Antiepileptic Drugs (MONEAD) study is a prospective, observational, multicenter investigation of pregnancy outcomes that enrolled women from December 19, 2012, to January 13, 2016, at 20 US epilepsy centers. Children are followed up from birth to 6 years of age, with assessment at 2 years of age for this study. Of 1123 pregnant women assessed, 456 were enrolled; 426 did not meet criteria, and 241 chose not to participate. Data were analyzed from February 20 to December 4, 2020. Main Outcomes and Measures: Language domain score according to the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III), which incorporates 5 domain scores (language, motor, cognitive, social-emotional, and general adaptive), and association between BSID-III language domain and ASM blood levels in the third trimester in children of WWE. Analyses were adjusted for multiple potential confounding factors, and measures of ASM exposure were assessed. Results: The BSID-III assessments were analyzed in 292 children of WWE (median age, 2.1 [range, 1.9-2.5] years; 155 female [53.1%] and 137 male [46.9%]) and 90 children of healthy women (median age, 2.1 [range, 2.0-2.4] years; 43 female [47.8%] and 47 male [52.2%]). No differences were found between groups on the primary outcome of language domain (-0.5; 95% CI, -4.1 to 3.2). None of the other 4 BSID-III domains differed between children of WWE vs healthy women. Most WWE were taking lamotrigine and/or levetiracetam. Exposure to ASMs in children of WWE showed no association with the language domain. However, secondary analyses revealed that higher maximum observed ASM levels in the third trimester were associated with lower BSID-III scores for the motor domain (-5.6; 95% CI, -10.7 to -0.5), and higher maximum ASM doses in the third trimester were associated with lower scores in the general adaptive domain (-1.4; 95% CI, -2.8 to -0.05). Conclusions and Relevance: Outcomes of children at 2 years of age did not differ between children of WWE taking ASMs and children of healthy women. Trial Registration: ClinicalTrials.gov Identifier: NCT01730170.


Subject(s)
Anticonvulsants/adverse effects , Cognition Disorders/etiology , Epilepsy/complications , Neurodevelopmental Disorders/etiology , Prenatal Exposure Delayed Effects/psychology , Adult , Anticonvulsants/blood , Child, Preschool , Cognition Disorders/epidemiology , Epilepsy/drug therapy , Female , Humans , Infant , Infant, Newborn , Language Development , Pregnancy , Pregnancy Outcome , Pregnant Women , Prenatal Exposure Delayed Effects/diagnostic imaging , Prospective Studies , Socioeconomic Factors
5.
Rev Sci Instrum ; 92(2): 024704, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33648153

ABSTRACT

Longwave (defined here as 500 Hz-500 kHz) radio science drives many scientific and engineering applications, including lightning detection and geolocation, subsea and subsurface sensing and communications, navigation and timing, and ionospheric and magnetospheric remote sensing. The hardware performance (i.e., sensitivity and bandwidth) of the receivers that detect long waves determines the maximum amount of information that can be extracted from the acquired data. In this paper, we present and describe an ultra-sensitive electric field receiver that enables broadband radio reception from near-DC up to 470 kHz, augmenting the legacy of the "Atmospheric Weather Electromagnetic System for Observation Modeling and Education" (AWESOME), a state-of-the-art magnetic field receiver completed previously. The AWESOME electric field receiver uses capacitive coupling with a dipole antenna to detect the electric field components of long waves and attains a sensitivity of 0.677 nV/(mHz). This sensitivity allows the detection of natural radio atmospherics and man-made beacon emissions at a global range. The AWESOME electric field receiver can also be integrated with a magnetic field sensor for simultaneous electric and magnetic field reception. In this paper, we detail the design of the receiver, including the receiver architecture, its working principles, design methodology, and trade-offs. We showcase the receiver performance characterized through both numerical models and empirical measurements. We demonstrate a novel calibration method that is quick and straightforward, suitable for deployments in the field. Finally, we demonstrate some novel applications enabled by this receiver's excellent sensitivity and simultaneous reception capability of electric and magnetic field components of long waves.

6.
Epilepsy Behav ; 117: 107688, 2021 04.
Article in English | MEDLINE | ID: mdl-33636531

ABSTRACT

OBJECTIVE: Folic acid supplementation during the periconceptual period has been shown to improve cognitive outcomes in children of women with epilepsy taking anti-seizure medications (ASMs). The dose of folic acid necessary to provide positive cognitive outcomes is unclear. In many countries including the United States, food is fortified with folic acid, but no data exist on how food fortification may affect cognition in children with fetal-ASM exposure. This study evaluated the effect of dietary folate from natural folates plus folic acid fortification, separate from folic acid vitamin supplements, on age-6 year IQ in children with fetal-ASM exposure. METHODS: Data from the Neurodevelopmental Effects of Antiepileptic Drugs (NEAD) study were retrospectively analyzed for this investigation. Assessment of nutrient intake was conducted using the Block Food Frequency Questionnaire-98. The primary outcome of the present study was to assess association of maternal prepregnancy nutrient levels to child age-6 IQ. RESULTS: Folate from food alone without supplement was not associated with improvement of age-6 IQ in children with fetal ASM exposure (95% CI: -11.7-2.3, p = 0.187). Periconceptual folate supplement use was associated with a 10.1-point higher age-6 IQ (95% CI: 5.2-15.0, p < .001). Total combined folate from food plus supplement also showed that higher intake of folate was associated with higher age-6 IQ (Coefficient: 4.5, 95% CI: 2.0-6.9, p < .001). Six other nutrients from food and supplements were analyzed (Vitamin C, Vitamin D, Vitamin E, Omega 3, Gamma Tocopherol, and Vitamin B12) and had no significant association with age 6-IQ. SIGNIFICANCE: Dietary content of folate, even in a country where food is fortified with folic acid, is not sufficient to provide improved cognitive outcomes for children of women taking ASMs during pregnancy. Folate supplementation is needed for significant improvement in cognitive outcomes, specifically age-6 IQ.


Subject(s)
Epilepsy , Folic Acid , Child , Dietary Supplements , Epilepsy/drug therapy , Female , Folic Acid/therapeutic use , Humans , Pregnancy , Retrospective Studies , United States , Vitamin B 12
7.
Adv Neonatal Care ; 21(5): 341-348, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-33315594

ABSTRACT

BACKGROUND: Human milk feeding is associated with decreased risk of necrotizing enterocolitis (NEC). PURPOSE: To determine whether a quality improvement project in New Jersey neonatal intensive care units (NICUs) to promote human milk (HM) feedings would be associated with a decrease in NEC. METHODS: Fourteen New Jersey NICUs engaged in efforts to reduce infection and promote HM feeding in very low birth-weight (VLBW) infants. Donor human milk (DHM) availability and NEC rates were assessed. RESULTS: From 2009 to 2016, NICUs with DHM increased from 0 to 7. VLBW infants discharged on any HM increased from 35% in 2007 before the formation of the New Jersey NICU Collaborative to more than 55% in 2016. Time to first oropharyngeal colostrum decreased from 37 to 30 hours from 2014 to 2016. HM at first feeding increased from 71% in 2013 to 82% in 2016. There was an increase in the percentage of feeds that were HM over the first 7 days of feeding. Analyses of data from 9400 VLBW infants born between 2009 and 2016 showed that the incidence of NEC when DHM was not available was 5.1% (367/7182) whereas the incidence when DHM was available (64/2218) was significantly lower (2.9%; P < .0001). IMPLICATIONS FOR PRACTICE: These findings show advantages of feeding HM and effectiveness of forming an NICU collaborative for improving care for preterm infants. IMPLICATIONS FOR RESEARCH: New research projects should measure the quantity of HM consumed daily during the entire NICU stay and assess the timing and amount of HM consumption in relationship to incidence of NEC and infection in neonates.


Subject(s)
Enterocolitis, Necrotizing , Milk, Human , Enterocolitis, Necrotizing/epidemiology , Enterocolitis, Necrotizing/prevention & control , Female , Humans , Incidence , Infant , Infant, Newborn , Infant, Premature , Infant, Very Low Birth Weight , Intensive Care Units, Neonatal
8.
Neurology ; 94(7): e729-e740, 2020 02 18.
Article in English | MEDLINE | ID: mdl-31871217

ABSTRACT

OBJECTIVE: Emerging evidence suggests potential positive neuropsychological effects of periconceptional folate in both healthy children and children exposed in utero to antiseizure medications (ASMs). In this report, we test the hypothesis that periconceptional folate improves neurodevelopment in children of women with epilepsy by re-examining data from the Neurodevelopmental Effects of Antiepileptic Drugs (NEAD) study. METHODS: The NEAD study was an NIH-funded, prospective, observational, multicenter investigation of pregnancy outcomes in 311 children of 305 women with epilepsy treated with ASM monotherapy. Missing data points were imputed with Markov chain Monte Carlo methods. Multivariate analyses adjusted for multiple factors (e.g., maternal IQ, ASM type, standardized ASM dose, and gestational birth age) were performed to assess the effects of periconceptional folate on cognitive outcomes (i.e., Full Scale Intelligence Quotient [FSIQ], Verbal and Nonverbal indexes, and Expressive and Receptive Language indexes at 3 and 6 years of age, and executive function and memory function at 6 years of age). RESULTS: Periconceptional folate was associated with higher FSIQ at both 3 and 6 years of age. Significant effects for other measures included Nonverbal Index, Expressive Language Index, and Developmental Neuropsychological Assessment Executive Function at 6 years of age, and Verbal Index and Receptive Language Index at 3 years of age. Nonsignificant effects included Verbal Index, Receptive Index, Behavior Rating Inventory of Executive Function-Parent Questionnaire Executive Function, and General Memory Index at 6 years of age, and Nonverbal Index and Expressive Index at 3 years of age. CONCLUSIONS: Use of periconceptional folate in pregnant women with epilepsy taking ASMs is associated with better cognitive development. CLINICALTRIALSGOV IDENTIFIER: NCT00021866.


Subject(s)
Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Folic Acid/therapeutic use , Pregnancy Complications/drug therapy , Protective Agents/therapeutic use , Adult , Child , Child, Preschool , Cognition , Female , Humans , Pregnancy , Prenatal Exposure Delayed Effects , Prospective Studies
9.
Epilepsy Behav ; 99: 106487, 2019 10.
Article in English | MEDLINE | ID: mdl-31476730

ABSTRACT

There is controversy in the literature as to how dissociable frontal lobe epilepsy (FLE) and temporal lobe epilepsy (TLE) are in terms of memory deficits. Some researchers have demonstrated that FLE is associated with greater executive dysfunction including working memory, whereas TLE is associated with greater memory impairment. Others have found the two groups to be comparable in memory functioning. Hence, we examined this question in children with FLE and TLE versus typically developing controls. We found most of the expected effects when the groups with focal onset epilepsy were compared to controls. Specifically, children with left TLE performed worse on verbal short-term memory/learning and long-term memory measures. In contrast, children with right TLE exhibited a more global pattern of difficulty on short-term memory/learning measures but performed worse than controls on long-term memory for faces. Children with FLE performed worse than controls on verbal working memory. Nevertheless, laterality effects were mild, as children with right and left TLE did not differ significantly from each other. Further, children with FLE did not differ from those with TLE on most measures except delayed facial recognition, where children with right TLE performed worse. In addition, attention problems and poor behavioral regulation were related to encoding problems in both the total epilepsy sample and in children with TLE specifically. Hence, our findings overall are consistent with prior studies indicating that children with TLE and FLE are commensurate in most aspects of memory impairment when compared to each other, likely related to rapid propagation between the frontal and temporal lobes, as would be expected with an excitatory lesion.


Subject(s)
Epilepsy, Frontal Lobe/physiopathology , Epilepsy, Temporal Lobe/physiopathology , Memory Disorders/physiopathology , Adolescent , Child , Epilepsy, Frontal Lobe/complications , Epilepsy, Temporal Lobe/complications , Female , Humans , Male , Memory Disorders/etiology , Neuropsychological Tests
10.
Epilepsy Behav ; 92: 154-164, 2019 03.
Article in English | MEDLINE | ID: mdl-30660966

ABSTRACT

The Neurodevelopmental Effects of Antiepileptic Drugs (NEAD) Study was a prospective observational multicenter study in the USA and UK, which enrolled pregnant women with epilepsy on antiepileptic drug (AED) monotherapy from 1999 to 2004. The study aimed to determine if differential long-term neurodevelopmental effects exist across four commonly used AEDs (carbamazepine, lamotrigine, phenytoin, and valproate). In this report, we examine fetal AED exposure effects on learning and memory functions in 221 six-year-old children (including four sets of twins) whose mothers took one of these AEDs during pregnancy. Their performance was compared with that of a national sample of normally developing six year olds from the standardization sample of the Children's Memory Scale (CMS). The major results of this study indicate that the mean performance levels of children exposed to valproate were significantly below that of the children in the normal comparison group across all seven of the CMS Indexes. With one exception, this finding held up at the subtest level as well. These findings taken together with nonsignificant verbal and nonverbal forgetting scores appear to indicate that, as a group, children exposed to valproate experienced significant difficulty in their ability to process, encode, and learn both auditory/verbal as well as visual/nonverbal material. In addition, they exhibited significant difficulty holding and manipulating information in immediate auditory working memory. However, once the information was learned and stored, the valproate-exposed children appeared to be able to retrieve the information they did learn at normal levels. Finally, the processing, working memory, and learning deficits demonstrated by the valproate-exposed children are dose-related. In contrast to valproate, the findings pertaining to the children exposed to carbamazepine, lamotrigine, and phenytoin in monotherapy are less clear. Therefore, further research will be required to delineate the potential risks to learning and memory functions in children exposed to carbamazepine, lamotrigine, and phenytoin in monotherapy during pregnancy. Additional research employing larger prospective studies will be required to confirm the long-term cognitive and behavioral risks to children of mothers who are prescribed these four AEDs during pregnancy as well as to delineate any potential risks of newer AEDs and to understand the underlying mechanisms of adverse AED effects on the immature brain.


Subject(s)
Anticonvulsants/administration & dosage , Epilepsy/drug therapy , Learning/drug effects , Memory Disorders/chemically induced , Memory/drug effects , Phenytoin/administration & dosage , Pregnancy Complications/drug therapy , Prenatal Exposure Delayed Effects/chemically induced , Adult , Anticonvulsants/adverse effects , Anticonvulsants/therapeutic use , Carbamazepine/administration & dosage , Carbamazepine/adverse effects , Carbamazepine/therapeutic use , Child , Female , Humans , Lamotrigine/administration & dosage , Lamotrigine/adverse effects , Lamotrigine/therapeutic use , Mothers , Phenytoin/adverse effects , Phenytoin/therapeutic use , Pregnancy , Prospective Studies , Valproic Acid/administration & dosage , Valproic Acid/adverse effects , Valproic Acid/therapeutic use
11.
Rev Sci Instrum ; 89(9): 094501, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30278759

ABSTRACT

We present the performance characteristics of a high-sensitivity radio receiver for the frequency band 0.5-470 kHz, known as the Low Frequency Atmospheric Weather Electromagnetic System for Observation, Modeling, and Education, or LF AWESOME. The receiver is an upgraded version of the VLF AWESOME, completed in 2004, which provided high sensitivity broadband radio measurements of natural lightning emissions, transmitting beacons, and radio emissions from the near-Earth space environment. It has been deployed at many locations worldwide and used as the basis for dozens of scientific studies. We present here a significant upgrade to the AWESOME, in which the frequency range has been extended to include the LF and part of the medium frequency (MF) bands, the sensitivity improved by 10-25 dB to be as low as 0.03 fT/ Hz , depending on the frequency, and timing error reduced to 15-20 ns range. The expanded capabilities allow detection of radio atmospherics from lightning strokes at global distances and multiple traverses around the world. It also allows monitoring of transmitting beacons in the LF/MF band at thousands of km distance. We detail the specification of the LF AWESOME and demonstrate a number of scientific applications. We also describe and characterize a new algorithm for minimum shift keying demodulation for VLF/LF transmitters for ionospheric remote sensing applications.

12.
Sci Rep ; 7(1): 16436, 2017 11 27.
Article in English | MEDLINE | ID: mdl-29180665

ABSTRACT

Gigantic Jets are electric discharges from thunderstorm cloud tops to the bottom of ionosphere at ~90 km altitude and electrically connect the troposphere and lower ionosphere. Since their first report in 2002, sporadic observations have been reported from ground and space based observations. Here we report first observations of Gigantic Jets in Indian subcontinent over the Indo-Gangetic plains during the monsoon season. Two storms each produced two jets with characteristics not documented so far. Jets propagated ~37 km up remarkably in ~5 ms with velocity of ~7.4 × 106ms-1 and disappeared within ~40-80 ms, which is faster compared to jets reported earlier. The electromagnetic signatures show that they are of negative polarity, transporting net negative charge of ~17-23 C to the lower ionosphere. One jet had an unusual form observed for the first time, which emerged from the leading edge of a slowly drifting complex convective cloud close to the highest regions at ~17 km altitude. A horizontal displacement of ~10 km developed at ~50 km altitude before connecting to the lower ionosphere. Modeling of these Gigantic jets suggests that Gigantic Jets may bend when initiated at the edge of clouds with misaligned vertical charge distribution.

13.
Appl Neuropsychol Child ; 6(4): 345-354, 2017.
Article in English | MEDLINE | ID: mdl-27355396

ABSTRACT

This is a retrospective study of 14 cases of children with Landau-Kleffner syndrome (LKS), the most prominent feature of which is acquired aphasia. These children were followed at a tertiary care pediatric epilepsy center. From the research data base, all LKS cases with neuropsychological evaluation were extracted. Children ranged in age from 6 to 13 years (M = 9.12; SD = 2.19) at the time of assessment (1 to 10 years post-onset). The majority of the children were white males, and all but one continued to experience seizure activity. Global intellectual functioning ranged from 59 to 101 (M = 82.07; SD = 12.14). Across the 14 cases reviewed, the neuropsychological profiles are considered in the context of neurological and syndrome-related factors. For these cases, 86% demonstrated continued expressive, and 50% had receptive language problems with 57% exhibiting poor auditory processing. Furthermore, 50 to 57% had deficits in auditory working memory and verbal memory. Academically, the majority had poor reading fluency and comprehension; 50% exhibited difficulty with mathematics. Finally, 57% evidenced attentional or other behavioral problems. Better understanding of LKS can assist in targeted assessment and intervention planning.


Subject(s)
Child Behavior/psychology , Cognition/physiology , Intelligence/physiology , Landau-Kleffner Syndrome/psychology , Academic Success , Adolescent , Child , Comprehension/physiology , Female , Humans , Landau-Kleffner Syndrome/complications , Male , Neuropsychological Tests , Retrospective Studies
14.
Child Neuropsychol ; 22(8): 979-1000, 2016.
Article in English | MEDLINE | ID: mdl-26156331

ABSTRACT

Prior research has shown that attention-deficit/hyperactivity disorder (ADHD) and epilepsy are frequently comorbid and that both disorders are associated with various attention and memory problems. Nonetheless, limited research has been conducted comparing the two disorders in one sample to determine unique versus shared deficits. Hence, we investigated differences in working memory (WM) and short-term and delayed recall between children with ADHD, focal epilepsy of mixed foci, comorbid ADHD/epilepsy and controls. Participants were compared on the Core subtests and the Picture Locations subtest of the Children's Memory Scale (CMS). Results indicated that children with ADHD displayed intact verbal WM and long-term memory (LTM), as well as intact performance on most aspects of short-term memory (STM). They performed worse than controls on Numbers Forward and Picture Locations, suggesting problems with focused attention and simple span for visual-spatial material. Conversely, children with epilepsy displayed poor focused attention and STM regardless of the modality assessed, which affected encoding into LTM. The only loss over time was found for passages (Stories). WM was intact. Children with comorbid ADHD/epilepsy displayed focused attention and STM/LTM problems consistent with both disorders, having the lowest scores across the four groups. Hence, focused attention and visual-spatial span appear to be affected in both disorders, whereas additional STM/encoding problems are specific to epilepsy. Children with comorbid ADHD/epilepsy have deficits consistent with both disorders, with slight additive effects. This study suggests that attention and memory testing should be a regular part of the evaluation of children with epilepsy and ADHD.


Subject(s)
Attention Deficit Disorder with Hyperactivity/physiopathology , Epilepsies, Partial/physiopathology , Memory Disorders/physiopathology , Memory, Long-Term/physiology , Memory, Short-Term/physiology , Adolescent , Attention , Attention Deficit Disorder with Hyperactivity/diagnosis , Attention Deficit Disorder with Hyperactivity/epidemiology , Child , Epilepsies, Partial/diagnosis , Epilepsies, Partial/epidemiology , Female , Humans , Male , Memory Disorders/epidemiology , Neuropsychological Tests , United States/epidemiology
15.
Pediatrics ; 136(6): 1080-6, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26574587

ABSTRACT

BACKGROUND AND OBJECTIVE: Central venous catheters in the NICU are associated with significant morbidity and mortality because of the risk of central line-associated bloodstream infections (CLABSIs). The purpose of this study was to determine the effect of catheter dwell time on risk of CLABSI. METHODS: Retrospective cohort study of 13,327 infants with 15,567 catheters (93% peripherally inserted central catheters [PICCs], 7% tunneled catheters) and 256,088 catheter days cared for in 141 NICUs. CLABSI was defined using National Health Surveillance Network criteria. We defined dwell time as the number of days from line insertion until either line removal or day of CLABSI. We generated survival curves for each week of dwell time and estimated hazard ratios for CLABSI at each week by using a Cox proportional hazards frailty model. We controlled for postmenstrual age and year, included facility as a random effect, and generated separate models by line type. RESULTS: Median postmenstrual age was 29 weeks (interquartile range 26-33). The overall incidence of CLABSI was 0.93 per 1000 catheter days. Increased dwell time was not associated with increased risk of CLABSI for PICCs. For tunneled catheters, infection incidence was significantly higher in weeks 7 and 9 compared with week 1. CONCLUSIONS: Clinicians should not routinely replace uninfected PICCs for fear of infection but should consider removing tunneled catheters before week 7 if no longer needed. Additional studies are needed to determine what daily maintenance practices may be associated with decreased risk of infection, especially for tunneled catheters.


Subject(s)
Catheter-Related Infections/epidemiology , Central Venous Catheters/adverse effects , Sepsis/epidemiology , Catheter-Related Infections/etiology , Cohort Studies , Female , Humans , Incidence , Infant , Infant, Newborn , Intensive Care Units, Neonatal , Male , Proportional Hazards Models , Retrospective Studies , Risk Factors , Sepsis/etiology , Time Factors , United States
16.
Appl Neuropsychol Child ; 4(3): 157-65, 2015.
Article in English | MEDLINE | ID: mdl-25117216

ABSTRACT

Math disorders have been recognized for as long as language disorders yet have received far less research. Mathematics is a complex construct and its development may be dependent on multiple cognitive abilities. Several studies have shown that short-term memory, working memory, visuospatial skills, processing speed, and various language skills relate to and may facilitate math development and performance. The hypotheses explored in this research were that children who performed worse on math achievement than on Full-Scale IQ would exhibit weaknesses in executive functions, memory, and visuoperceptual skills. Participants included 436 children (27% girls, 73% boys; age range = 5-17 years, M(age) = 9.45 years) who were referred for neuropsychological evaluations due to academic and/or behavioral problems. This article specifically focuses on the spectrum of math weakness rather than clinical disability, which has yet to be investigated in the literature. Results suggest that children with relative weakness to impairments in math were significantly more likely to have cognitive weaknesses to impairments on neuropsychological variables, as compared with children without math weaknesses. Specifically, the math-weak children exhibit a weakness to impairment on measures involving attention, language, visuoperceptual skills, memory, reading, and spelling. Overall, our results suggest that math development is multifaceted.


Subject(s)
Learning Disabilities/psychology , Mathematics , Memory, Short-Term/physiology , Problem Solving/physiology , Reading , Adolescent , Attention/physiology , Child , Child, Preschool , Female , Humans , Male , Neuropsychological Tests
17.
Appl Neuropsychol Child ; 4(4): 277-84, 2015.
Article in English | MEDLINE | ID: mdl-25495770

ABSTRACT

Research with adults with epilepsy consistently indicates deficits in executive function (EF). There is less research specific to children with epilepsy and EF. The purpose of this study was to consider EF deficits in children with complex partial epilepsy and complex partial with secondary generalization epilepsy with onset localized to the frontal or temporal lobes. This was a retrospective study of 28 children followed in an outpatient pediatric epilepsy clinic who were consecutively referred for neuropsychological assessment, which included measures of EF. The sample was predominantly White and male, with a mean age of 12.88 years (SD = 1.64) and mean cognitive ability of 89.39 (SD = 13.41). Comparison of right-temporal, left-temporal, and frontal groups yielded significant differences (p = .01) between the left-temporal and frontal groups on the Wisconsin Card-Sorting Test (WCST) Categories with the frontal group demonstrating the greatest deficits. Although mean differences were not significant, the frequency of impaired performance by the frontal group on the Attention/Concentration Index was greater than in the temporal groups. Results indicate that for children with complex partial and complex partial with secondary generalized seizures localized to the frontal and temporal lobes, there is an increased likelihood for impaired EF evident on the WCST, but not on others. Implications of these findings for prevention and intervention are discussed.


Subject(s)
Attention/physiology , Epilepsy, Frontal Lobe/physiopathology , Epilepsy, Temporal Lobe/physiopathology , Executive Function/physiology , Neuropsychological Tests , Adolescent , Child , Female , Humans , Male , Retrospective Studies
18.
Neurology ; 84(4): 382-90, 2015 Jan 27.
Article in English | MEDLINE | ID: mdl-25540307

ABSTRACT

OBJECTIVE: To delineate the risk to child IQ associated with frequently prescribed antiepileptic drugs. METHODS: Children born to women with epilepsy (n = 243) and women without epilepsy (n = 287) were recruited during pregnancy and followed prospectively. Of these, 408 were blindly assessed at 6 years of age. Maternal and child demographics were collected and entered into statistical models. RESULTS: The adjusted mean IQ was 9.7 points lower (95% confidence interval [CI] -4.9 to -14.6; p < 0.001) for children exposed to high-dose (>800 mg daily) valproate, with a similar significant effect observed for the verbal, nonverbal, and spatial subscales. Children exposed to high-dose valproate had an 8-fold increased need of educational intervention relative to control children (adjusted relative risk, 95% CI 8.0, 2.5-19.7; p < 0.001). Valproate at doses <800 mg daily was not associated with reduced IQ, but was associated with impaired verbal abilities (-5.6, 95% CI -11.1 to -0.1; p = 0.04) and a 6-fold increase in educational intervention (95% CI 1.4-18.0; p = 0.01). In utero exposure to carbamazepine or lamotrigine did not have a significant effect on IQ, but carbamazepine was associated with reduced verbal abilities (-4.2, 95% CI -0.6 to -7.8; p = 0.02) and increased frequency of IQ <85. CONCLUSIONS: Consistent with data from younger cohorts, school-aged children exposed to valproate at maternal doses more than 800 mg daily continue to experience significantly poorer cognitive development than control children or children exposed to lamotrigine and carbamazepine.


Subject(s)
Anticonvulsants/adverse effects , Carbamazepine/adverse effects , Child Development/drug effects , Epilepsy/drug therapy , Intelligence/drug effects , Pregnancy Complications/drug therapy , Prenatal Exposure Delayed Effects/chemically induced , Triazines/adverse effects , Valproic Acid/adverse effects , Adult , Anticonvulsants/administration & dosage , Carbamazepine/administration & dosage , Child , Female , Humans , Lamotrigine , Male , Pregnancy , Prospective Studies , Triazines/administration & dosage , Valproic Acid/administration & dosage
19.
Dev Neuropsychol ; 39(8): 569-84, 2014.
Article in English | MEDLINE | ID: mdl-25470222

ABSTRACT

In a sample of individuals with childhood focal epilepsy, children/adolescents with left hemisphere foci outperformed those with right foci on both measures of nonverbal learning. Participants with left foci performed worse than controls on paired associate delayed recall and semantic memory, and they had greater laterality effects in IQ. Participants with right foci performed worse than controls on delayed facial recognition. Both groups displayed reduced focused attention and poor passage retention over time. Although participants with bilateral foci displayed poor learning and lower IQ than controls, they did not have worse impairment than those with a unilateral focus.


Subject(s)
Brain/physiopathology , Epilepsies, Partial/physiopathology , Functional Laterality/physiology , Memory/physiology , Mental Recall/physiology , Adolescent , Attention/physiology , Brain/pathology , Case-Control Studies , Child , Epilepsies, Partial/pathology , Female , Humans , Intelligence/physiology , Intelligence Tests , Learning , Male , Neuropsychological Tests
20.
JAMA Pediatr ; 168(8): 729-36, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24934501

ABSTRACT

IMPORTANCE: Breastfeeding is known to have beneficial effects, but concern exists that breastfeeding during maternal antiepileptic drug (AED) therapy may be harmful. We previously noted no adverse effects of breastfeeding associated with AED use on IQ at age 3 years, but IQ at age 6 years is more predictive of school performance and adult abilities. OBJECTIVES: To examine the effects of AED exposure via breastfeeding on cognitive functions at age 6 years. DESIGN, SETTING, AND PARTICIPANTS: Prospective observational multicenter study of long-term neurodevelopmental effects of AED use. Pregnant women with epilepsy receiving monotherapy (ie, carbamazepine, lamotrigine, phenytoin, or valproate) were enrolled from October 14, 1999, through April 14, 2004, in the United States and the United Kingdom. At age 6 years, 181 children were assessed for whom we had both breastfeeding and IQ data. All mothers in this analysis continued taking the drug after delivery. MAIN OUTCOMES AND MEASURES: Differential Ability Scales IQ was the primary outcome. Secondary measures included measures of verbal, nonverbal, memory, and executive functions. For our primary analysis, we used a linear regression model with IQ at age 6 years as the dependent variable, comparing children who breastfed with those who did not. Similar secondary analyses were performed for the other cognitive measures. RESULTS: In total, 42.9% of children were breastfed a mean of 7.2 months. Breastfeeding rates and duration did not differ across drug groups. The IQ at age 6 years was related to drug group (P < .001 [adjusted IQ worse by 7-13 IQ points for valproate compared to other drugs]), drug dosage (regression coefficient, -0.1; 95% CI, -0.2 to 0.0; P = .01 [higher dosage worse]), maternal IQ (regression coefficient, 0.2; 95% CI, 0.0 to 0.4; P = .01 [higher child IQ with higher maternal IQ]), periconception folate use (adjusted IQ 6 [95% CI, 2-10] points higher for folate, P = .005), and breastfeeding (adjusted IQ 4 [95% CI, 0-8] points higher for breastfeeding, P = .045). For the other cognitive domains, only verbal abilities differed between the breastfed and nonbreastfed groups (adjusted verbal index 4 [95% CI, 0-7] points higher for breastfed children, P = .03). CONCLUSIONS AND RELEVANCE: No adverse effects of AED exposure via breast milk were observed at age 6 years, consistent with another recent study at age 3 years. In our study, breastfed children exhibited higher IQ and enhanced verbal abilities. Additional studies are needed to fully delineate the effects of all AEDs. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00021866.


Subject(s)
Anticonvulsants/adverse effects , Breast Feeding , Cognition Disorders/chemically induced , Developmental Disabilities/chemically induced , Epilepsy/drug therapy , Intelligence/drug effects , Prenatal Exposure Delayed Effects/chemically induced , Child , Female , Humans , Intelligence Tests , Male , Pregnancy , Prospective Studies , United Kingdom , United States
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