A substantial body of previous research suggests that the medial prefrontal cortex (MPFC) plays an important role in multiple aspects of emotion. These aspects include, but are not limited to, (1) generating, (2) experiencing, and (3) regulating one's own emotional state, as well as (4) facilitating the use of emotion-related information within goal-directed cognition and action selection. However, there is considerable controversy with regard to the distinct functional roles of various MPFC subregions. In this dissertation, I first provide a review of the theoretical and experimental literature to date in order to defend a plausible model of the hierarchical neural processes associated with each of the aspects of emotion highlighted above. This model proposes that different MPFC subregions each play distinct, but interactive, roles at or near the top of the respective hierarchical systems associated with those aspects of emotion. After reviewing this model, I then provide a description of four experiments that test the predictions of this model's claims regarding the roles of three distinct MPFC subregions: the rostral anterior cingulate cortex (rACC), the dorsomedial prefrontal cortex (DMPFC), and the ventromedial prefrontal cortex (VMPFC). These experiments provide independent support for the claims that (1) rACC plays an important role in representing the conceptual meaning of one's felt emotional reactions, (2) DMPFC plays an important role in maintaining representations of one's own emotions within a consciously accessible state, and (3) VMPFC plays an important role in both appraising the emotional significance of one's current situation and triggering the somatic/visceral reactions associated with the generation of an emotional response. In the concluding section of the dissertation, I then integrate these findings together with the larger model and discuss important directions for future research as well as ways in which the model might be extended to include insights from recent advances in theoretical neuroscience associated with predictive coding.

This early phase study examined the effects of a series of ten standard-protocol acupuncture treatments over four weeks in 12 healthy, but symptomatic, menopausal women. Two biologic markers, heart rate variability to evaluate effects of acupuncture on the autonomic nervous system as it relates specifically to the heart, and interleukin 6, a proinflammatory cytokine, to capture physiologic impact of acupuncture on the immune-inflammatory response, were collected.Women who exhibited significant menopausal symptoms, as measured by a minimum score of 22 out of a possible 44 points on the Menopause Rating Scale (MRS), underwent 10 sessions of a standard acupuncture point protocol intervention over a four-week period. Symptoms were evaluated for 28 days using the MRS. After the intervention was complete, one final open-ended question was asked of each participant to explore subjective experiences not captured by the validated instrument. Physiologic measurements included a 30-minute continuous measure of electrocardiogram data before and during acupuncture, as well as pre and post acupuncture measures of serum interleukin 6 at the first and final acupuncture treatment. Heart rate variability was assessed using spectral analysis, and interleukin 6 changes were measured using ELISA. Analysis included linear regression, Wilcoxon Signed Ranks test and Spearman correlation coefficients.After the acupuncture intervention, menopausal symptoms improved significantly. Heart rate variability did not show consistent or predictable intra or inter-subject changes, however several components of HRV, interleukin 6 and symptoms were found to have significant correlations.A larger study was deemed feasible. Menopause symptoms improved. Heart rate variability showed no consistent changes or trends. Interleukin 6 decreased in seven subjects, between the first and tenth acupuncture treatment, but did not reach statistical significance.This small project suggests that heart rate variability, when measured at each acupuncture treatment, does not change in a consistent or predictable manner. Rather, acupuncture may provide a modulating influence that depends on the body's functional state at each treatment.

Recent research has suggested that boredom is a construct that can be distinguished from similar affective states including apathy, anhedonia, and depression, using self-reports. The current study investigated whether boredom and sadness (an analogue for depression) are distinct in terms of their physiological signatures. State boredom and sadness were induced in a group of healthy participants while their physiological parameters of heart rate (HR), skin conductance (SCL), and cortisol levels were monitored. Results indicated that the autonomic nervous system response for both states can be characterized by directional fractionation, with boredom resulting in increased HR but decreased SCL relative to sadness. Cortisol levels were higher after the boring induction than the sad induction, indicating increased hypothalamic-pituitary-adrenal axis activation for boredom. Overall, boredom appears to have a physiological signature that is distinguishable from a primary symptom of depression.

Hypertension in pregnancy is associated with autonomic dysregulation whereas the effects of obesity in pregnancy on maternal cardiac autonomic function are poorly understood. Furthermore, hypertension in pregnancy is associated with placental insufficiency and fetal growth restriction, whereas obesity in pregnancy is associated with placental inflammation and macrosomia. Fetal growth restriction is associated with an increased risk for language deficits at 2-5 years of age. However, maternal cardiac autonomic function and fetal auditory processing in pregnancies complicated by hypertension compared to obesity have not been examined and are the focus of this study. Maternal short-term cardiac autonomic modulation in the supine and standing postures as well as spontaneous and auditory elicited fetal behaviours were compared in 61 mother-fetal pairs (n=20 hypertensive; n=20 overweight; n=21 normal weight comparison pregnancies) from 34 to 40 weeks gestation. Maternal cardiovascular measures included systolic arterial finger-cuff blood pressure and electrocardiographic recordings of heart rate. Spontaneous observations of fetal heart rate, body and breathing movements, muscle tone and an estimate of amniotic fluid were made. Finally, each fetus received a 2 min recording of their mother and the mother’s voice in reverse (counterbalanced over subjects). When standing (othostatic stress), all three groups of women exhibited a decrease in the average baroreflex slope, parasympathetic nervous system indicator and high frequency power compared to the supine position. In a 20 min observation of spontaneous behaviour in the maternal supine compared to the standing position, fetuses of hypertensive mothers had, on average, fewer heart rate accelerations ≥ 15 bpm while the mother was supine; fetuses in the normal weight comparison group experienced more accelerations while the mother was supine. The average number of heart rate accelerations did not change in the two maternal positions for fetuses in the obese group. Fetuses in the three groups showed differential responses to the mother’s voice played forward and backward. It was concluded that there were no differences in maternal heart rate variability measures in the group of mildly hypertensive women compared to those with obesity and the normal weight comparison group. Differential spontaneous fetal heart rate accelerations and responses to the mother’s voice among the three groups needs further study with sufficient sample size to examine behaviour as a function of gestational age. / Thesis (Master, Nursing) -- Queen's University, 2009-03-13 17:45:41.837

Exergames combine physical activity and entertainment in an effort to increase people’s motivation to exercise. Multiplayer exergames attempt to include the motivating aspects of group activity by allowing two or more people to play together. In most multiplayer exergames, a player’s in-game performance is limited by her physical abilities. Less fit players are demotivated by repeated losses to more fit opponents, while fitter players face a lack of competition from unfit opponents. This situation makes it difficult for people of disparate physical abilities to play exergames together. This research presents heart rate balancing, a novel player balancing technique to better support engaging experiences in multiplayer exergames. Heart rate balancing bases players’ in-game performance on their effort relative to fitness level rather than their raw power. More specifically, heart rate monitoring is used to set in-game performance based on how closely a person adheres to her target heart rate. Experiments with heart rate balancing show that the technique improves competition between players. A strong correlation was found between people’s perceived effort and their in-game performance with heart rate balancing. The degree to which players noticed the balancing mechanism varied depending on game type. However, heart rate balancing did not interfere with people’s ability to play exergames. These results indicate that the heart rate balancing technique is a promising approach for improving enjoyment and engagement in multiplayer exergames. / Thesis (Ph.D, Computing) -- Queen's University, 2012-09-26 23:38:57.625

No description available.

Chronic stress is endemic to modern society. If we could monitor our mental state, we may be able to develop insights about how we respond to stress. However, it is unfeasible to continuously annotate stress levels all the time. In the studies conducted for this dissertation, a minimally-invasive wearable sensor platform and physiological data processing methods were developed to analyze a number of physiological correlates of mental stress. We present a minimally obtrusive wearable sensor system that incorporates embedded and wireless communication technologies. The system is designed such that it provides a balance between data collection and user comfort. The system records the following stress related physiological and contextual variables: heart rate variability (HRV), respiratory activity, electrodermal activity (EDA), electromyography (EMG), body acceleration, and geographical location. We assume that if the respiratory influences on HRV can be removed, the residual HRV will be more salient to stress in comparison with raw HRV. We develop three signal processing methods to separate HRV into a respiration influenced and residual HRV. The first method consists of estimating respiration-induced portion of HRV using a linear system identification method (autoregressive moving average model with exogenous inputs). The second method consists of decomposing HRV into respiration-induced principal dynamic mode and residual using nonlinear dynamics decomposition method (principal dynamic mode analysis). The third method consists of splitting HRV into respiration-induced power spectrum and residual in frequency domain using spectral weighting method. These methods were validated on a binary discrimination problem of two psychophysiological conditions: mental stress and relaxation. The linear system identification method, nonlinear dynamics decomposition method, and spectral weighting method classified stress and relaxation conditions at 85.2 %, 89.2 %, and 81.5 % respectively. When tonic and phasic EDA features were combined with the linear system identification method, the nonlinear dynamics decomposition method, and the spectral weighting method, the average classification rates were increased to 90.4 %, 93.2 %, and 88.1 % respectively. To evaluate the developed wearable sensors and signal processing methods on multiple subjects, we performed case studies. In the first study, we performed experiments in a laboratory setting. We used the wearable sensors and signal processing methods to discriminate between stress and relaxation conditions. We achieved 81 % average classification rate in the first case study. In the second study, we performed experiments to detect stress in ambulatory settings. We collected data from the subjects who wore the sensors during regular daily activities. Relaxation and stress conditions were allocated during daily activities. We achieved a 72 % average classification rate in ambulatory settings. Together, the results show achievements in recognizing stress from wearable sensors in constrained and ambulatory conditions. The best results for stress detection were achieved by removing respiratory influence from HRV and combining features from EDA.

Exercise prescription intensity is traditionally defined using a target heart rate (HR) as a surrogate measure of oxygen uptake (V02). The ACSM Guidelines recommends the use of a percentage of the maximal HRR because it is thought to match a similar percentage of maximal V02 (%V02max). However, several recent studies have challenged the notion that a given percentage of MHRR matches with the same percentage of V02max in older subjects. The purpose of this study was to assess the difference between percentages of MHRR and V02ma, and evaluate the influence of age on the agreement between these two variables across a range of exercise intensities. The sample included 530 subjects (232 men and 298 women, mean ages of 46.6 + 11.7 years and 43.3 + 11.3 years respectively) who completed a maximal treadmill test to volitional fatigue using the BSU/Bruce Ramp protocol. Heart rate and V02 data from minutes 3, 6, and 9 were converted into percentages of MHRR and V02mai,. Subjects were excluded from the analysis if they failed to achieve an RER,„a,,>1.0. Minutes 3, 6, and 9 represented 45.2 ± 11, 66.0 ± 15, and 83.1 ± 12% of VO2.x, respectively. A one-way ANOVA showed that statistically significant differences existed between the treatment means of relative intensity at minutes 3, 6, and 9 at a p-value of <0.05. The influence of age was assessed by correlation with the difference between percentages of MHRR and VO2max at minutes 3, 6, and 9. In addition, younger (<60 years of age) and older (>60 years of age) subjects were compared using an unpaired t-test. The association between age and the difference between percentages of HRR and VO2max were -0.24, -0.22, and - 0.26 at minutes 3, 6, and 9, respectively. The difference in the relative intensities of HRR and VO2max was greater for older subjects at minutes 3 and 6 (-7.0 vs. -2.2, -3.2 vs. -0.8%) but was smaller at minute 9 (-0.1 vs. -3.2%). A Scheffe post-hoc analysis was used to compare the differences between the treatment means of relative intensity. In conclusion, these results confirm the notion that percentages of MHRR. tend to underestimate percentages of VO2max in older subjects, however the differences observed within the present study were smaller than those reported previously. The small but statistically differences between the techniques would not appear to invalidate the use of percentages of MHRR as surrogate markers of percentages of VO2max in these subjects. / School of Physical Education

No description available.

The objectives for the first part of this thesis were to describe changes in oxygen saturation (SpO2) and heart rate (HR) in newly born infants in the delivery room (DR) and to illustrate the changes using centile reference charts. The objective of the second part of the thesis was to investigate whether infants < 29 weeks gestation who receive positive pressure ventilation (PPV), immediately after birth with a T-piece have higher SpO2 measurements at five minutes than infants ventilated with a self inflating bag (SIB). / Study Design. A prospective observational study was used to achieve the first objectives. For the second part of the thesis I coordinated a randomised, controlled trial of two devices used for resuscitation of extremely preterm infants in the DR where the primary outcome measure was SpO2. / Patients and methods. In all studies a Masimo Radical pulse oximeter (PO) was placed on the infant’s right hand/wrist immediately after birth. PO data (oxygen saturation, HR and signal quality) were downloaded every 2 sec and analysed only when the signal had no alarm messages (low IQ signal, low perfusion, sensor off, ambient light). / Results. Observational studies: The dataset to develop the reference range charts included 61,650 data points from 468 infants. Infants had a mean (range) gestational age of 38 (25-42) weeks and birthweight 2970 (625-5135) g. For all 468 infants at one minute the 3rd, 10th, 50th, 90th and 97th centiles were 29%, 39%, 66%, 87% and 92%; at two minutes 34%, 46%, 73%, 91% and 95% and at five minutes 59%, 73%, 89%, 97% and 98%. It took a median of 7.9 (IQR 5.0 to 10) minutes to reach a SpO2 > 90%. SpO2 of preterm infants rose more slowly than that of term infants. At one min the median (IQR) HR was 82 (66 to 138) bpm rising at two min and five min to 151 (112 to 169) bpm and 166 (148 to 176) bpm respectively. In preterm infants, the SpO2 and HR rose more slowly than term infants. / Randomised trial: Forty nine infants were randomly allocated to the T-piece and 50 to the SIB. Ten infants did not receive PPV, 4 (8%) in the T-piece group and 6 (12%) in the SIB group and were not included in the analysis. Forty-one infants received PPV with a T-piece and 39 with a SIB. At 5 minutes after birth there was no significant difference between the mean (SD) SpO2 in the T-piece and SIB groups [50 (31)% vs. 53 (25)%, (p=0.73)]. More T-piece infants received oxygen during DR resuscitation (100% vs. 90%, p=0.04). There was no significant difference between the groups in the use of continuous positive airway pressure (CPAP); endotracheal intubation or administration of surfactant in the DR. Fewer of the T-piece group who left the DR on CPAP were intubated in the first 24 hrs after birth. (7% vs. 23%, p=0.05). / Conclusion. The centile charts developed in this thesis provide a reference range for SpO2 and HR in the first 10 minutes after birth for preterm and term infants. In the randomised trial there was no significant difference in SpO2 at five minutes after birth in extremely preterm infants given PPV with a T-piece or a SIB.