Brain Mechanisms Supporting the Modulation of Pain by Mindfulness Meditation

The subjective experience of one’s environment is constructed by interactions among sensory, cognitive, and affective processes. For centuries, meditation has been thought to influence such processes by enabling a nonevaluative representation of sensory events. To better understand how meditation influences the sensory experience, we used arterial spin labeling functional magnetic resonance imaging to assess the neural mechanisms by which mindfulness meditation influences pain in healthy human participants. After 4 d of mindfulness meditation training, meditating in the presence of noxious stimulation significantly reduced pain unpleasantness by 57% and pain intensity ratings by 40% when compared to rest. A two-factor repeated-measures ANOVA was used to identify interactions between meditation and pain-related brain activation. Meditation reduced pain-related activation of the contralateral primary somatosensory cortex. Multiple regression analysis was used to identify brain regions associated with individual differences in the magnitude of meditation-related pain reductions. Meditation-induced reductions in pain intensity ratings were associated with increased activity in the anterior cingulate cortex and anterior insula, areas involved in the cognitive regulation of nociceptive processing. Reductions in pain unpleasantness ratings were associated with orbitofrontal cortex activation, an area implicated in reframing the contextual evaluation of sensory events. Moreover, reductions in pain unpleasantness also were associated with thalamic deactivation, which may reflect a limbic gating mechanism involved in modifying interactions between afferent input and executive-order brain areas. Together, these data indicate that meditation engages multiple brain mechanisms that alter the construction of the subjectively available pain experience from afferent information

Petrology of the hastingsite-riebeckite Granite of Mt. Cabot, NH

Abstract The purpose of this study was to produce a model of the petrogenesis of the Mt. Cabot hastingsite-riebeckite granite located in the northern half of the Northern Jefferson 7.5\u27 quadrangle. This study aims to build on the structural information and the map produced by Hillenbrand (2017) as part of the USGS/NHGS StateMap program. The Mt. Cabot area contains older surrounding bed rock of the Middle-Upper Ordovician Ammonoosuc Volcanics, the Lost Nation group, Jurassic igneous intrusives of the Pliny ring dike complex, and xenoliths of Conway Granite. The hastingsite-riebeckite granite is the largest pluton in the area. The pluton is part of the White Mountain Magma series and was formed after the tectonic events involving the Early-Mid Mesozoic opening of the Atlantic Ocean and part of the magmatic melting associated with ring dike formation and caldera collapses. I analyzed samples of the hastingsite-riebeckite granite pluton of Mt. Cabot, NH, for their mineralogy, textures, and geochemistry. Discrete zones of hastingsite and riebeckite bearing granites suggest varying oxygen fugacity conditions across the magma body during crystallization or that distinct Na-rich or Ca-rich magmas makeup the pluton. Modal analysis shows two different rock types within the pluton, syenogranite, and quartz syenite. Exsolved alkali feldspar indicates crystallization at low pressure and depth, around 1.5- 2.1 kbar and 5.3- 7.6 km. Intergranular albite and albite rims on alkali feldspars indicate late stage albitization and replacement and unmixing of alkali feldspar at 410 ºC and 370ºC during crystallization. Sericitization of alkali feldspar and hydration of amphiboles suggest post magmatic hydrothermal alteration. XRF bulk-rock geochemistry and trace element data suggest that the Mt. Cabot granite is chemically similar to other riebeckite granites of the New Hampshire region. The discrete mineralogical zones were most likely caused by the influx and movement of melt that are controlled by the structural nature and instability of ring dike complexes

The Ideal Free Distribution of Group Choice: A social psychology of human behavior

This dissertation presents an experimental analysis of social behavior. The behavior is called Group Choice (Baum & Kraft, 1998) and the analysis is a social foraging model called the Ideal Free Distribution (IFD; Fretwell & Lucas, 1970). The IFD is a social foraging model that describes the distribution of a group of foragers in a patchy environment. Group Choice describes group members engaging in two behaviors. The IFD suggests that group members engage in two behaviors in the same relative relation to the consequences obtained from those behaviors. The IFD of Group Choice is analogous to the Matching Law analysis of individual choice (Baum, 1974; Herrnstein, 1961, 1970; Kennedy & Gray, 1993). The results showed consistent IFD matching of the groups\u27 choices to the point distributions when unequal amounts of points were shared among subgroup members (Experiments 1, 2, 7a, and 7b). In contrast, the groups undermatched point distributions when the points were allocated probabilistically. Groups tended to match to the same degree regardless of the type of behavior alternative (i.e., sitting in chairs or choosing cards). Not being able to ideally distribute (imperfect solutions) tended to reduce group sensitivity to the distribution of points. Assigning different competitive weights to participants did not have an impact on group choice. Overall, the groups\u27 choices before knowing what others chose were more variable, but similar to the choices made after knowing what others chose. Analyses of individuals\u27 consistency in preferences and obtained points from block-to-block of trials failed to reveal order on the individual level that could explain the group level results. A promising analysis of individuals\u27 choices between alternatives and obtained points from those alternatives also did not reveal a satisfactory explanation for group level results. The analogy between an IFD analysis of Group Choice and a Matching Law analysis of individual choice may be far reaching. Whereas an individual\u27s responses match the relative consequences, group members\u27 behavior match the relative resources. Basic equations for both relations can be expressed in ratio form and generalized to account for deviations as a power function. Undermatching is the common result for both lines of research. Whereas the Matching Law describing individual choice became the foundation for the quantification of the Law of Effect and decades of fruitful research, it remains to be seen if the IFD of Group Choice stimulates similar progress. If the analogy between the Matching Law analysis of individual choice and the IFD of Group Choice is thoroughgoing, this research may provide the foundation for the quantification of a social level Law of Effect. (Abstract shortened by UMI.)

Aircraft IR/acoustic detection evaluation. Volume 2: Development of a ground-based acoustic sensor system for the detection of subsonic jet-powered aircraft

The design and performance of a ground-based acoustic sensor system for the detection of subsonic jet-powered aircraft is described and specified. The acoustic detection system performance criteria will subsequently be used to determine target detection ranges for the subject contract. Although the defined system has never been built and demonstrated in the field, the design parameters were chosen on the basis of achievable technology and overall system practicality. Areas where additional information is needed to substantiate the design are identified

Secondary Fusion Reactions in the Mechanical Adiabatic Compression of a Dense Plasma

We consider fusion processes initiated by the rapid adiabatic compression by a piston of a deuterium plasma contained in a well‐insulated chamber. To exploit the n^2 factor in the fusion reaction rate, we consider one mole of deuterium which, at ambient temperature and pressure, provides a particle density of ~ 10^19 cm^‐3. The reaction rate is enhanced by the application of magnetic and electric fields to reduce the number of degrees of freedom of the gas, thereby lowering its heat capacity and producing a higher temperature increase for a given energy input. Previous studies have shown that the combination of adiabatic operation, high particle density and reduced degrees of freedom can result in appreciable fusion rates at temperatures lower than those in magnetic confinement experiments. The prior work considered only primary D-D fusion reactions while the present work also includes D-T reactions. Conditions of energy-break-even and excess energy release were found at temperatures of the order of 10^6 K

Multistage Fusion Reaction Rates in an Adiabatically Compressed Plasma

A poster discussing fusion reaction rates in adiabatically compressed plasma