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• We propose a curve-fitting technique that complements existing estimation tools. • The average WTP for 1 Mbps faster internet is $1.13 per month. • The average WTP for a 1-tier quality upgrade is $45.52 per month. • Users with the lowest speed/quality benefit the most from a given internet subsidy. • WTP largely varies based on income and employment status. This paper adds to a growing literature on the willingness to pay (WTP) for internet services. We surveyed 5,200 respondents across four demographically diverse United States (US) states, and developed a curve-fitting WTP estimation technique that builds on existing conjoint analysis models. We find that users are willing to pay an extra $1.13 per month for a 1 megabits per second (Mbps) faster internet and $45.52 per month for better connection quality. We document a strong non-linearity: a given speed increment generates the most value for users with the slowest internet but confers negligible value on users with the fastest internet. Specifically, improving speed from 1 Mbps to 25 Mbps creates 2.32 times more value than improving from 25 Mbps to 100 Mbps. A similar non-linearity arises in terms of internet quality. We report large WTP discrepancies by income levels and employment status. The results corroborate that internet subsidies are most impactful if they first assist users with the poorest internet access. In this sense, subsidizing the right population could be as important as – if not more important than – raising funds to subsidize internet access. [ABSTRACT FROM AUTHOR]

Abstract: In this study we aimed to develop a habituation paradigm that allows the investigation of response decrement and response recovery and examine its applicability for measuring the habituation of the visually evoked responses (VERs) in neonatal and fetal magnetoencephalographic recordings. Two paradigms, one with a long and one with a short inter-train interval (ITI), were developed and tested in separate studies. Both paradigms consisted of a train of four light flashes; each train being followed by a 500Hz burst tone. Healthy pregnant women underwent two prenatal measurements and returned with their babies for a neonatal investigation. The amplitudes of the neonatal VERs in the long-ITI condition showed within-train response decrement. An increased response to the auditory dishabituator was found confirming response recovery. In the short-ITI condition, neonatal amplitude decrement could not be demonstrated while response recovery was present. In both ITI conditions, the response rate of the cortical responses was much lower in the fetuses than in the neonates. Fetal VERs in the long-ITI condition indicate amplitude decline from the first to the second flash with no further decrease. The long-ITI paradigm might be useful to investigate habituation of the VERs in neonates and fetuses, although the latter requires precaution. [Copyright &y& Elsevier]

Abstract: Using non-invasive fetal magnetoencephalography (fMEG), we investigated spontaneous brain activity in 28 fetuses diagnosed with intrauterine growth restriction (IUGR) and compared the results to 47 normal-growth fetuses. The fetal gestational age ranged from 28 to 39weeks with post-natal recordings obtained on 17 of the IUGR fetuses. Power spectrum was computed and was divided into four frequency bands. A significant difference in the relative spectral power in delta, theta and beta bands (P<0.01) was observed only in the 28–32week gestation age group with alpha band showing a similar trend (P=0.054). This observation suggests that growth restriction may have a more pronounced effect on the fetal brain in early gestation. Larger population studies could reveal the potential value of fMEG as an additional surveillance tool for growth-restricted fetuses. [Copyright &y& Elsevier]

The world''s first magnetoencephalography (MEG) system specifically designed for fetal and newborn assessment has been installed at the University of Arkansas for Medical Sciences. This noninvasive system called SARA (SQUID Array for Reproductive Assessment) consists of 151 primary superconducting sensors that detect biomagnetic fields from the human body. Since the installation of SARA, significant progress has been made toward the ultimate goal of developing a clinical neurological assessment tool for the developing fetus. Using appropriate analysis techniques, cardiac and brain signals are recorded and studied to gain new understanding of fetal maturation. It is clear from our investigations that a combination of assessment protocols including both fetal heart and brain activity is necessary for the development of a comprehensive new method of fetal neurological testing. We plan to implement such a test protocol for fetuses at high risk for neurological impairment due to certain maternal risk factors and/or fetal diagnostic findings. [Copyright &y& Elsevier]

Abstract: Objective: Utilizing a MEG-based device specifically designed to study the fetus, we investigated the presence of salient patterns in spontaneous fetal brain activity. Methods: We performed 91 MEG recordings from 30 fetuses at various gestational ages. The tracings were evaluated and compared to the well-established electroencephalographic (EEG) features in premature infants. Also, we looked at the correlation of the gestational age (GA) on the occurrence of these patterns and complexes. Results: We were able to identify specific patterns and track changes in fetal brain activity starting at 28weeks of gestation. The patterns and trends were similar to the established EEG features in premature infants at comparable ages. Of the 30 fetuses, 18 (60%) had at least one recording with discontinuity, 7 (23%) had sharp transients, and 8 (27%) had delta brush activity. Further there was a decrease in the presence of discontinuous patterns after 35weeks. Conclusions: We have shown that fetal spontaneous brain activity features can be recorded and identified using MEG technique. The observation of more discontinuity at early gestational ages is consistent with the overall pattern of maturation seen in EEGs of premature infants. Significance: With refinements, this method can aid in understanding the maturation process of fetal brain activity and further develop as a tool for fetal neurological evaluation. [Copyright &y& Elsevier]

Abstract: The mismatch negativity (MMN) response elicited to auditory stimuli is an indicator for cognitive function of sound discrimination in humans. MMN was successfully recorded in previous studies in newborns and fetuses (33–40 weeks of gestation) with magnetoencephalography (MEG). The aim of our study was to perform systematic serial MMN recordings on fetuses starting at 28 weeks of gestation with a follow up recording within 2 weeks after birth. The recording of weak magnetic fields from the fetal brain were performed with the 151 channel MEG system called SARA (SQUID Array for Reproductive Assessment). Two tone bursts were presented in a sequence of a standard complex tone of 500 Hz intermixed with a deviant complex tone of 750 Hz in 12% of the stimuli, inter-stimulus interval 800±100 ms. Eighteen pregnant women between 28th and 39th gestational weeks participated in the study. Measurements were performed every two weeks and once after delivery. The averaged evoked responses to standard and deviant tones were obtained and subtraction between them was calculated. A successful detection of response to the frequency change was found in 66% of the fetal data and 89% of the neonatal data. Responses to the standard tone were detected in 56% of all records. In the 28–39 week gestational age group, the discriminative brain responses to tone frequency change could be detected as early as 28 weeks. Although not statistically significant, a decrease in latency was observed with increase in gestational age. The ability of the fetus to detect changes in sounds is a prerequisite to normal development for cognitive function; related to language learning and clinical aspects of auditory disorders. [Copyright &y& Elsevier]

Abstract: An intact auditory system at birth is requisite for the successful accomplishment of many developmental skills. Evoked responses to auditory stimuli have been used as a sensitive test to determine the functional status of the adult and neonatal brain. It has been established that fetuses can hear in utero and respond to external acoustic stimuli. We present an overview of the transmission of sound through the maternal abdomen to the fetal ear and the recordings of an auditory evoked response obtained from the fetus using a non-invasive magnetoencephalography technique. The investigation of cortical activity of the fetus in response to auditory stimulation can help understand and track the neurological development of the fetus. [Copyright &y& Elsevier]

Summary: The assessment of the neurological integrity of the human fetus in utero is a technically challenging problem. New brain imaging devices can substantially improve our capabilities to describe functional brain activity in the fetus. It has been well established by fetal behavioral studies and investigations in preterm and term newborns that the brain is functional in utero. The major effort required to perform effective neurological functional investigations is designation of an integrated approach to neurological assessment and the generation of normative data. Currently, it is possible to record evoked brain activity elicited by auditory and visual stimulation from the fetus. In addition, there is growing evidence that spontaneous brain activity can be recorded in the fetus. This paper explores the current status of the brain-imaging field for fetal investigations and currently available data. [Copyright &y& Elsevier]

Abstract: Objective: To investigate the maturation of the auditory cortex by non-invasive recording of auditory evoked magnetic fields in human fetuses and newborns with the relatively novel and completely non-invasive technology of MEG. Methods: Serial recordings were performed every 2 weeks on 18 fetuses beginning from week 27 of gestational age until term with a follow-up recording on the newborn. Auditory stimulation consisted of tone bursts in an oddball design with standard tones and deviant tones. Results: In 52 of 63 fetal and in all of the neonatal recordings an auditory evoked magnetic field was obtained. A decrease in latency with increasing age of the subjects was observed in the combined analysis of fetuses and neonates. Conclusions: With advanced study using MEG, 83% of the measurements showed auditory evoked fields in fetuses that correspond with existing literature in electrophysiology in the past. These findings indicate that MEG is a technique that can be used to investigate maturation of the auditory cortex based on auditory evoked fields in fetuses and neonates. Significance: Maturational changes have been examined in the past. With the use of this novel technique, applied to a serial study, it is possible to trace the development of auditory responses in utero and newborns. [Copyright &y& Elsevier]

The study objective was to determine whether short-term serial magnetoencephalographic (MEG) measurements would increase the odds in favor of obtaining fetal auditory evoked responses in normal fetuses. The recordings were performed in two phases using the newly developed 151-channel fetal MEG system, superconducting quantum interference device array for reproductive assessment. Ten pregnant subjects with gestational ages ranging from 30–35 weeks were recruited to participate. Daily recordings were performed over a minimum of 3 days during 1 week of gestation and repeated in the same subjects between 36 and 40 weeks gestation. In 80% of subjects, auditory evoked responses were detected at least once. In healthy fetuses, serial recordings over a short span of time increased the rate of detecting fetal evoked response. [Copyright &y& Elsevier]

We aim to evaluate the effects of the telemedicine program, High-Risk Pregnancy Program at University of Arkansas for Medical Sciences (UAMS), on health services utilization and medical expenditures among pregnant women with pre-existing diabetes and their newborns. The study sample was selected from the Arkansas Medicaid claims linked to infant birth/death certificates and UAMS telemedicine records from 2013 through 2016. We used propensity score matching based on participants' characteristics to create three groups - UAMS telemedicine care, UAMS in-person care, and non-UAMS prenatal care. We compared inpatient and outpatient care services, medication use and caesarean section rates, severe maternal morbidity, infant mortality and preterm birth rates and medical expenditures. The UAMS telemedicine group had fewer inpatient admissions (1.18 vs 1.31; 95% CI: -0.27, 0.00), lower insulin use rates (41.86% vs 59.88%; 95% CI: -29.00%, -7.05%) and lower maternal care expenditures ($7,846 vs $10,644; 95% CI: -$4,089, -$1,507) compared with the UAMS in-person care group. Women receiving UAMS telemedicine had more prenatal care visits (10.45 vs 8.57; 95% CI: -2.96, -0.81), higher insulin use rates (41.86% vs 26.74%: 95% CI: 4.63%, 25.60%) and similar maternal care expenditures ($7,846 vs $7,051), compared with those receiving non-UAMS in-person care. Caesarean section, severe maternal morbidity, and infant mortality rates were similar across the three groups. UAMS telemedicine was associated with improved utilization of prenatal care among pregnant women with pre-existing diabetes. Telemedicine services did not differ from usual in-person services in clinical outcomes and medical expenditures. [ABSTRACT FROM AUTHOR]

Objective: The study goal was to examine the impact of commonly prescribed antiemetic medications in pregnancy on neurobehavioral and obstetric outcomes. Study Design: Five hundred thirty-three women accounting for 550 live births (17 multiple gestations) enrolled before 16 weeks' gestation participating in an observational longitudinal study of stress and pharmacologic exposure in pregnancy at Emory Women's Mental Health Program were included in this study. Maternal report of exposure to medications was documented by weeks of use. Obstetric and neonatal data were obtained from medical records. The Neonatal Behavioral Assessment Scale was completed by certified raters at age 7 days. The Child Behavior Checklist (CBCL) was completed by the mother between 17 and 66 months of age. Comparison of groups was conducted using χ2 and Wilcoxon rank-sum tests. Spearman correlation analysis was used for CBCL percentile scores to evaluate duration of exposure. Results: The exposed group (n = 143) was comprised of children whose mothers received promethazine or ondansetron during pregnancy. Unexposed children (n = 407) were used for comparison. Neonatal Behavioral Assessment Scale data 7 days (range, 2–77) was available on 345 infants (exposed n = 102; unexposed n = 243), and a total of 247 CBCLs (exposed n = 51; unexposed n = 196) at 29 (range, 17–66) months of age. No significant differences were seen using Neonatal Behavioral Assessment Scale and CBCL. Statistically significant differences were seen in gestational age at delivery (0.3 weeks) and birthweight (110 g). Conclusion: No clinically significant adverse neurobehavioral effects or obstetric outcomes were identified. This is reassuring as promethazine and ondansetron are commonly prescribed during pregnancy. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The objective was to extract, quantify and characterize the uterine magnetomyographic (MMG) signals that correspond to the electrophysiological activity of the uterus. Methods: Transabdominal MMG recordings with high spatial–temporal resolution were performed with the use of the 151 non-invasive magnetic sensor system. The extraction, quantification and characterization procedures were developed and applied to representative MMG signals that were recorded from a pregnant woman at regular intervals starting at 37 weeks of gestation until the subject reached active labor. Results: Multiple MMG recordings were successfully performed on the subject before she went into active labor. The extracted MMG burst activity showed a statistically significant correlation (r =0.2; p <0.001) with the contractile events perceived by mothers. The time–frequency analysis of the burst activity showed a power shift towards higher-frequency at 48h before the subject went into active labor as compared to earlier recordings. Further there was a gradual increase in the synchrony in the higher-frequency band as the subject reached close to active labor. Conclusions: The non-invasive recording of the magnetic signals of pregnant uterus with high spatial–temporal resolution can provide an insight into the preparatory phase of labor and has the potential of predicting term and preterm labor. [Copyright &y& Elsevier]

• Fetal magnetocardiography was acquired with a semi-rigid prototype optically-pumped magnetometers (OPM) sensor array. • OPM system has the ability to record quality fetal cardiac activities and is capable of identifying lethal cardiac rhythm disturbances in the fetus across gestation ages. • We were able to quantify the variation in fetal heart rate viability parameters. • Fetal biomagnetometry with OPM could be translated in the future from research to widespread clinical applications. To record and extract features of fetal cardiac activities with a semi-rigid prototype optically-pumped magnetometers (OPM) sensor array. Fetal magnetocardiography (fMCG) data were collected from 15 pregnant women between 28 and 40 weeks gestation. Mothers were lying flat in a customized bed with sensors touching their abdomen from below using a prototype grid. fMCG was extracted to perform standard fetal heart rate variability (FHRV) analysis. fMCG was observed in 13 of the 15 pregnant women. OPM FHRV indicators were in the range of previous SQUID studies. Semi-rigid prototype OPM system has the ability to record quality fMCG. fMCG is capable of identifying lethal cardiac rhythm disturbances in the fetus. Our novel application of OPM technology may lower costs and increase maternal comfort, thus expanding fMCG's generalizability. [ABSTRACT FROM AUTHOR]

Highlights: [•] Examined fetal neurological maturation indices in normal pregnancies using magnetoencephalographic recordings. [•] Interburst interval (IBI) decreases with gestational age – a trend similar to EEG findings in premature neonates. [•] Tracking IBI in quiet sleep state could provide valuable insight into fetal neurological maturation. [ABSTRACT FROM AUTHOR]

Abstract: Background: Intrauterine growth restriction (IUGR) is a fetal condition characterized by growth-rate reduction. Afflicted fetuses tend to display abnormalities in heart rate. Objective: To study the differences in the heart-rate variability of low-risk fetuses and IUGR fetuses during different behavioral states. Methods: A total of 40 fetal magnetocardiograms were analyzed from 20 low-risk and 20 IUGR fetuses recorded using a 151-sensor SQUID-array system. The maternal cardiac signals were attenuated using signal–space projection. Fetal R waves were identified using an adaptive Hilbert transform approach and fetal heart rate was calculated. In each three-minute window, the heart rate was classified into patterns reflective of quiet sleep (pattern A) and active sleep (pattern B) using the criteria of Nijhuis. Two adjacent 3-min windows exhibiting the same pattern were selected for analysis from every dataset. Heart-rate variability in that 6-min window was characterized using three measures, standard deviation of normal to normal (SDNN), root mean square of successive differences (RMSSD) and phase plane area (PPA). Results: All three measures tended to be lower in the IUGR group compared to the low-risk group. However, when the measures were analyzed in patterns, only PPA showed significant difference between the risk groups in pattern A, whereas both PPA and SDNN showed highly significant risk-group differences in pattern B. RMSSD did not show any significant risk-group difference. Conclusion: The result signifies that the heart-rate variability of IUGR fetuses is different from that of low-risk fetuses, and only PPA was able to capture the HRV differences in both quiet and active states. The difference between these two groups of fetuses shows that the fetal-activity states are potential confounders when characterizing heart-rate variability. [Copyright &y& Elsevier]

Abstract: Background: The processing of rapidly presented stimuli has been shown to be a precursor for the perception of speech in infants, long before they learn to speak. However, the onset and early development of rapid temporal processing (RTP) skills is not yet well understood. The main goal of this study was to assess the development of RTP skills during the prenatal and early postnatal stages of life. Methodology: Tone pairs were presented in two difficulties (long and short) and event-related magnetic fields were recorded using MEG. Pregnant women (22) (gestational ages between 29 and 38weeks’) participated in the fetal study and 15 returned for a neonatal follow-up study between 2 and 38days after delivery or 38 and 44weeks gestational age (GA). Results: In the postnatal follow-up study, a trend towards two peaks with increasing chronological and gestational age was observed in the longer tone pair. However, no such trend was evident in neonatal responses to the short tone pairs or in fetal recordings. Conclusions: Neonates showed a gradual trend to successful processing of the longer tone pair with increasing age. By 22days of chronological age, the infants processed this tone pair successfully, as indicated by two-peak waveforms. Therefore, the first 3weeks of life could be critical for the development of RTP. Significance: This study is a first approach towards the assessment of early RTP development. The results provide promising indications for future studies, which might lead to an early detection of deficits in speech perception and therefore prevent further language impairments. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate the response decrements of visual evoked responses (VER) in newborns and assess the applicability of this paradigm to fetuses in magnetoencephalographic (MEG) recordings. Methods: Twelve newborns with no known risks or complications participated at chronological ages between 6 and 22days. They constituted the follow-up group to a prenatal study conducted on a sample of 25 fetuses whose gestational age (GA) varied between 29 and 37weeks at the time of recording. Trains of four light flashes with an interstimulus interval of 2s followed by 10s without stimulation were delivered to record VER. Results: Nine of the 12 newborns responded to the stimulation and showed response decrements in amplitude from the first to the last light flash. Furthermore, the response latency increased significantly from the first to the last stimulus. The remaining three recordings were discontinued early. Even though the prenatal visual evoked response rate was only 29%, the fetuses exhibited a response decrement after the first stimulus. Conclusions: The amplitude of VERs can be used to elicit a response decrement in newborns and, with limitations, even in fetuses. This paradigm might be a useful tool for a direct non-invasive assessment of neonatal and prenatal brain development and CNS functioning. Significance: The proposed method might be a first step towards an early detection of developmental deficits in newborns and fetuses. [Copyright &y& Elsevier]

Abstract: Objective: To describe magnetoencephalography (MEG) recordings in a cohort of healthy neonates. Methods: We performed MEG and single channel EEG concomitantly in 21 healthy newborns. MEG and EEG signals were reviewed for gross comparison of general patterns and individual waveform characteristics. Spectral analysis was performed to quantify the signals. Results: Our MEG recordings showed patterns comparable to classical neonatal EEG. Seventy-nine percent of the subjects exhibited the ‘continuous polyfrequency activity’ at some point in their recording. Sixty-three percent had the ‘continuous slow’ pattern, and 47% had the ‘trace alternant’ pattern. Spectral analysis revealed maximal power at frequencies of less than 4Hz (delta band) in both MEG and EEG with a decline towards higher frequencies. Conclusions: Neonatal MEG is feasible and shares the basic EEG features and frequency content, with predominant activity in the slow frequency delta band. The latter corresponds to reports from earlier neonatal EEG studies. Significance: MEG may prove to be useful in studies of neonatal brain functions. [Copyright &y& Elsevier]