iPhysioMeter: A new approach for measuring heart rate and normalized pulse volume using only a smartphone

Heart rate (HR) and normalized pulse volume (NPV) are physiological indices that have been used in a diversity of psychological studies. However, measuring these indices often requires laborious processes. We therefore developed a new smartphone program, named iPhysioMeter, that makes it possible to measure beat-by-beat HR and ln NPV using only a smartphone. We examined its accuracy against conventional laboratory measures. Mental stress tasks were used to alter HR and ln NPV in 12 participants. Bland–Altman analyses revealed negligible proportional bias for HR and ln NPV or for their change values, expressed as ΔHR and Δln NPV. However, a relatively large fixed bias did emerge for ln NPV, as well as a small one for Δln NPV, although both were within the limits of agreement. These findings suggest that iPhysioMeter can yield valid measures of the absolute level of HR and of relative changes in ln NPV

Performance measures of alcohol-induced impairment: Towards a practical ignition-interlock system for motor vehicles

金沢大学大学院自然科学研究科Performance-based alcohol screening devices may help reduce road traffic accidents, but there is a shortage of easy-to-use performance tests available. To address this issue, four recently developed rapid, computerized, easily implementable performance tests, Spiral for iPhone and Spiral for Mac (psycho-motor tests), and the Modified Mental Rotation and Catch the Rabbit tests (cognitive tests), were assessed, testing participants at predrink baseline and then during three progressive amounts of alcohol intake. Analyses showed all tests were performed statistically significantly less accurately at 0.11% blood alcohol concentrations (BACs) than at 0.00% BAC, as were all tests except Spiral for iPhone at 0.06% BAC. These results indicate the suitability of all of these tests for measuring alcohol-induced impairment, and some potential for use as a practical performance-based alcohol screening device. © Perceptual and Motor Skills 2009

Controlled mechanical vibration applied to driver\u27s right heel to sustain alertness: Effects on cardiovascular behavior

Vehicle-related countermeasures to sustain driver\u27s alertness might improve traffic safety. The purpose of this study was to investigate the effects of somatosensory 20. Hz mechanical vibration, applied to driver\u27s right heel during prolonged, simulated, monotonous driving, on their cardiovascular hemodynamic behavior. In 12 healthy young male volunteers, during 90-min periods of simulated monotonous driving, we compared cardiovascular variables during application of 20. Hz mechanical vibration with 1.5. Hz as a control and with no vibration. The parameters recorded were indices of key cardiovascular hemodynamic phenomena, i.e., blood pressure as an indicator of stress, cardiac output, and total peripheral-vascular resistance. The principle results were that all conditions increased the mean blood pressure, and elicited a vascular-dominant reaction pattern typically observed in monotonous driving tasks. However, mean blood pressure and total peripheral-vascular resistance during the monotonous task were significantly decreased in those receiving the 20. Hz vibration as compared with 1.5. Hz and with no vibration. The observed differences indicate the cardiovascular system being more relieved from monotonous driving stress with the 20. Hz vibration. The major conclusion is that applying 20. Hz mechanical vibration to the right heel during long-distance driving in non-sleepy drivers could facilitate more physiologically appropriate status for vehicle operation and could be a potential vehicular countermeasure technology. © 2013 Elsevier Ltd

Cardiovascular hemodynamic effects of Red Bull® Energy Drink during prolonged, simulated, monotonous driving

Purpose: The purpose of this study was to investigate the cardiovascular hemodynamic effects of Red Bull® Energy Drink during prolonged, simulated, monotonous driving. Methods: This was a double-blind, within-subjects-design, crossover study. Twelve healthy volunteers (21.7 ± 0.8 years old) experienced each of three conditions at various times: 1) consumption of Red Bull® Energy Drink; 2) consumption of placebo-controlled drink; and 3) no test drink. All subjects undertook 90-min periods of simulated monotonous driving, during which physiological measurements were made. The variables recorded were cardiovascular indices, i.e., mean blood pressure (MBP), cardiac output (CO), electrocardiogram RR interval (RR), total peripheral-vascular resistance (TPR: = MBP/CO), and normalized pulse volume (NPV). Additional parameters were the standard deviation of lateral position, i.e., the weaving of the car, and subjective rating of sleepiness. Results: CO, RR, and TPR during the monotonous task were significantly different in those consuming the energy drink as compared with those receiving the placebo and as compared with no drink values. The energy drink elicited a cardiac-dominant reaction pattern, while the other conditions demonstrated the vascular-dominant reaction pattern typically observed in monotonous driving tasks. The observed differences indicate the cardiovascular system being more aroused with the energy drink. Conclusion: The effects of Red Bull® Energy Drink were reflected in cardiovascular hemodynamic phenomena especially to the heart function, and we conclude that consumption of this drink before long-distance driving in non-sleepy drivers could facilitate more physiologically active, and possibly safer, driving. © 2013 Yamakoshi et al

Maternal dietary intake of fish and child neurodevelopment at 3 years: a nationwide birth cohort—The Japan Environment and Children's Study

BackgroundResults on the association between fish intake during pregnancy and a reduction in neurodevelopmental delays in children have been inconsistent, with some reports finding an association and others finding none. Because neurodevelopmental delays are more pronounced at the age of 3 years, their association needs to be examined at this age.MethodsAfter exclusion and multiple imputation from a dataset comprising 104,057 records from the Japan Environment and Children's Study, logistic regression analysis was conducted in quintiles to evaluate the association between maternal fish intake during pregnancy and child neurodevelopment at age 3 years in 91,909 mother–child pairs. The Food Frequency Questionnaire (FFQ), validated in the Japan Public Health Center-Based Prospective Study for the Next Generation, was used to assess maternal fish intake during pregnancy. The Ages and Stages Questionnaires-3 was used to assess children's neurodevelopment in five domains: communication, gross motor, fine motor, problem-solving, and personal-social.ResultsConsistently lower odds were found for the highest vs. lowest quintile for the domains of communication, fine motor, problem-solving, and personal-social but not gross motor skills, with adjusted odd ratios (95% confidence intervals) of 0.89 (0.80–0.998), 0.90 (0.83–0.97), 0.86 (0.80–0.94), 0.87 (0.77–0.98), and 1.04 (0.94–1.16), respectively. The trend for lower odds of symptoms of neurodevelopmental delays across quintiles of higher maternal fish intake were significant for fine motor, problem-solving, and personal-social but not communication or gross motor.ConclusionsFish consumption during pregnancy may be associated with a reduced risk of neurodevelopmental delay in 3-year-olds, particularly in the fine motor, problem-solving, and personal-social domains. Continued investigation after the age of 3 could further clarify the association

The effect of omega-3 fatty acids on psychophysiological assessment for the secondary prevention of posttraumatic stress disorder: an open-label pilot study.

Our recent pilot study has shown that the supplementation of omega-3 fatty acids (fish oil) immediately after a traumatic event may be effective toward the secondary prevention of post-traumatic disorder (PTSD). To lay the groundwork for addressing the mechanism by which omega-3 fatty acids can prevent PTSD, we analyzed its psychophysiological data. The psychophysiological data included heart rate, skin conductance, and continuous blood pressure during patient subjection to startling tones and idiographic trauma-related cues. Of the 8 patients, 1 met the diagnostic criteria for PTSD. Compared to the seven patients without PTSD, one patient with PTSD showed relatively large reactivity to the startle tones. In contrast, this patient did not show large reactivity to the trauma-related cue during script-driven imagery. The combination of psychophysiological measurements in our randomized control trial should shed light on the underlying mechanisms by which omega-3 fatty acids can prevent PTSD

Side-scattered finger-photoplethysmography: experimental investigations toward practical noninvasive measurement of blood glucose

The aim of this study was to discover a simple/convenient geometrical arrangement of radiation sources and detector to acquire finger-photoplethysmograms (PPGs) with wavelength regions of blood glucose (BGL) absorption, toward practical noninvasive BGL measurement. First, we compared PPGs with three wavelengths: 808 nm (without water absorption), 1160 nm (with weak water absorption), and 1600 nm (with nearly peak BGL absorption and strong water absorption), while the source-detector spacing was successively increased circumferentially around a fingertip. In 10 healthy subjects, we observed clear cardiac-related pulsatile components of PPG signals at 808 and 1160 nm in any incident positions with more than 15 dB of signal-to-noise ratio (S/N), but reliable PPG detections at 1600 nm with more than 10 dB of S/N was only possible when the source-detector distance was less than 3mm around the fingertip circumference. Second, with this arrangement, an experiment was performed using six wavelengths to cover glucose absorption bands (from 1550 to 1749 nm), obtaining pulsatile PPG signals with more or less 15 dB of S/N. Through the present experiments, this orthogonal arrangement of the source and detector to detect forward-and side-scattered radiation through the tissue is appropriate for PPG measurements with wavelength regions where there is potential for BGL measurement

Physiological measurements and analyses in motor sports: A preliminary study in racing kart athletes

金沢大学自然科学研究科The aims of this study were to assess methods for performing physiological measurements in motor sports, and to carry out a preliminary study in athletes participating in kart racing. The measurement of physiological variables in motor sports is practically challenging, largely due to the restricted space available for sensors and instrumentation and to movement artefacts from driver\u27s operations and car vibration, hence the paucity of publications. We performed a preliminary study of amateur racing kart athletes to assess the performance of basic measurement apparatus and to collect preliminary data on the possible influences of gravity on cardiovascular activity. We measured the vector magnitude of acceleration (G), instantaneous heart rate using electrocardiography, blood pressure with a wrist sphygmomanometer, eardrum temperature (taken as a measure of core body temperature) with a radiation thermometer, and lap time. The instrumentation functioned satisfactorily during karting on a racing circuit. In all participants during driving, heart rate was maintained at approximately 150 beats min 1. Time-frequency analysis of all heart rate data was performed to evaluate cardiac control mechanisms and this suggested that the observed rise in heart rate could be due to sympathetic acceleration. Furthermore, while we do not have sufficient data to draw firm conclusions, it is suggested that the rise in heart rate could be related to the G stresses to which the drivers were subjected. Cross-correlation analysis of the G and heart rate signals was performed in one participant and this showed a statistically significant correlation. We also found a statistically significant decrease in blood pressure (P<0.01) and a rise in eardrum temperature (P<0.01) immediately after the driving period. We conclude that although current sensors and instrumentation can allow basic monitoring of physiological variables in motor sport athletes, further developments are needed to allow more detailed investigations to be performed. Cardiovascular activity in response to G stresses warrants particular detailed investigation. © 2010 European College of Sport Science

Impact of longer working hours on fathers’ parenting behavior when their infants are 6 months old: The Japan Environment and Children’s Study

ObjectiveLong working hours have been suggested to affect fathers’ parenting behavior, but previously reported findings have been inconsistent. This study examined the association between the working hours and parenting behavior of fathers while accounting for other factors related to their parenting behavior, using data from the Japan Environment and Children Study (JECS), a large cohort study in Japan.MethodsData from 43,159 father–mother pairs were analyzed. The mother assessed the father’s frequency of seven parenting behaviors at 6 months after delivery. Then, each behavior was classified into a high-engagement group (always and sometimes) or a low-engagement group (rarely and never). The father’s weekly working hours was obtained from his responses and was classified into six levels.ResultsLogistic regression analysis showed that after adjustment for covariates, fathers’ weekly working hours was inversely associated with the frequency of all parenting behaviors examined in this study (p for trend &lt;0.0001). Compared with fathers working ≥0 to ≤40 h per week, those working &gt;65 h per week showed the following adjusted odds ratios (95% confidence intervals) for low engagement in parenting behaviors: playing at home, 2.38 (2.08–2.72); changing diapers, 2.04 (1.89–2.20); and bathing the child, 2.01 (1.84–2.18).ConclusionThis study suggests that the greater time constraints imposed by longer working hours constitute a major factor that discourages fathers from engaging in childrearing behavior. Intervention targeting long working hours could contribute to measures aimed at promoting high-engagement parenting behaviors among fathers

Comparison between red, green and blue light reflection photoplethysmography for heart rate monitoring during motion

Reflection photoplethysmography (PPG) using 530 nm (green) wavelength light has the potential to be a superior method for monitoring heart rate (HR) during normal daily life due to its relative freedom from artifacts. However, little is known about the accuracy of pulse rate (PR) measured by 530 nm light PPG during motion. Therefore, we compared the HR measured by electrocadiography (ECG) as a reference with PR measured by 530, 645 (red), and 470 nm (blue) wavelength light PPG during baseline and while performing hand waving in 12 participants. In addition, we examined the change of signal-to-noise ratio (SNR) by motion for each of the three wavelengths used for the PPG. The results showed that the limit of agreement in Bland-Altman plots between the HR measured by ECG and PR measured by 530 nm light PPG (±0.61 bpm) was smaller than that achieved when using 645 and 470 nm light PPG (±3.20 bpm and ±2.23 bpm, respectively). The ΔSNR (the difference between baseline and task values) of 530 and 470nm light PPG was significantly smaller than ΔSNR for red light PPG. In conclusion, 530 nm light PPG could be a more suitable method than 645 and 470nm light PPG for monitoring HR in normal daily life. © 2013 IEEE