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Is Cognitive Neuropsychology Plausible? The Perils of Sitting on a One-Legged Stool
We distinguish between strong and weak cognitive neuropsychology, with the former attempting to provide direct insights into the nature of information processing and the latter having the more modest goal of providing constraints on such theories. We argue that strong cognitive neuropsychology, although possible, is unlikely to succeed and that researchers will fare better by combining behavioral, computational, and neural investigations. Arguments offered by Caramazza (1992) in defense of strong neuropsychology are analyzed, and examples are offered to illustrate the power of alternative points of view.Psycholog
Central Extensions of Finite Heisenberg Groups in Cascading Quiver Gauge Theories
Many conformal quiver gauge theories admit nonconformal generalizations.
These generalizations change the rank of some of the gauge groups in a
consistent way, inducing a running in the gauge couplings. We find a group of
discrete transformation that acts on a large class of these theories. These
transformations form a central extension of the Heisenberg group, generalizing
the Heisenberg group of the conformal case, when all gauge groups have the same
rank. In the AdS/CFT correspondence the nonconformal quiver gauge theory is
dual to supergravity backgrounds with both five-form and three-form flux. A
direct implication is that operators counting wrapped branes satisfy a central
extension of a finite Heisenberg group and therefore do not commute.Comment: 25 pages, 12 figure
Vacuum stability and the Cholesky decomposition
We discuss how the Cholesky decomposition may be used to ascertain whether a
critical point of the field theory scalar potential provides a stable vacuum
configuration. We then use this method to derive the stability conditions in a
specific example.Comment: 7 page
Tree Level Metastability and Gauge Mediation in Baryon Deformed SQCD
We investigate supersymmetric QCD with gauge group SU(2) and a baryon
deformation to the superpotential. The existence of an uplifted vacuum at the
origin with tree level metastability is demonstrated. When this model is
implemented in a direct gauge mediation scenario we therefore find gaugino
masses which are comparable to sfermion masses and parameterised by an
effective number of messengers 1/8. All deformations are well motivated by
appealing to the electric theory and an R-symmetry. This R-symmetry is
explicitly broken by the same term responsible for supersymmetry breaking.
Moreover, the model does not suffer from the Landau pole problem and we find
that it can be described in terms of just two scales: the weak scale and a high
scale like the Planck or GUT scale. The model can be tested by searching for
new particles at the TeV scale charged under the visible sector gauge group.Comment: 17 pages, 7 figures, updated reference
Unilateral Right Parietal Damage Leads to Bilateral Deficit for High-Level Motion
AbstractPatients with right parietal damage demonstrate a variety of attentional deficits in their left visual field contralateral to their lesion. We now report that patients with right lesions also show a severe loss in the perception of apparent motion in their âgoodâ right visual field ipsilateral to their lesion. Three tests of attention were conducted, and losses were found only in the contralesional fields for a selective attention and a multiple object tracking task. Losses in apparent motion, however, were bilateral in all cases. The deficit in apparent motion in the parietal patients supports previous claims that this relatively effortless percept is mediated by attention. However, the bilateral deficit suggests that the disruption is due to a bilateral loss in the temporal resolution of attention to transient events that drive the apparent motion percept
Dibaryon Spectroscopy
The AdS/CFT correspondence relates dibaryons in superconformal gauge theories
to holomorphic curves in Kaehler-Einstein surfaces. The degree of the
holomorphic curves is proportional to the gauge theory conformal dimension of
the dibaryons. Moreover, the number of holomorphic curves should match, in an
appropriately defined sense, the number of dibaryons. Using AdS/CFT backgrounds
built from the generalized conifolds of Gubser, Shatashvili, and Nekrasov
(1999), we show that the gauge theory prediction for the dimension of
dibaryonic operators does indeed match the degree of the corresponding
holomorphic curves. For AdS/CFT backgrounds built from cones over del Pezzo
surfaces, we are able to match the degree of the curves to the conformal
dimension of dibaryons for the n'th del Pezzo surface, n=1,2,...,6. Also, for
the del Pezzos and the A_k type generalized conifolds, for the dibaryons of
smallest conformal dimension, we are able to match the number of holomorphic
curves with the number of possible dibaryon operators from gauge theory.Comment: 30 pages, 6 figures, corrected refs; v3 typos correcte
Neutrino-induced lepton flavor violation in gauge-mediated supersymmetry breaking
Gauge-mediated supersymmetry breaking is known to greatly suppress flavor
changing neutral current effects. However, we show that gauge mediation in the
context of leptogenesis implies potentially large lepton flavor violating
signals. If the heavy right-handed neutrinos that participate in leptogenesis
are lighter than the messenger scale of gauge mediation, they will induce
flavor off-diagonal masses to the sleptons which in turn can induce large
effects in mu to e gamma, tau to mu gamma, and mu-e conversion in nuclei. We
demonstrate this result and compute numerically the lepton-flavor violating
decay and conversion rates in scenarios of direct gauge mediation.Comment: 18 pages, 5 figure
Examining the difference between 10- and 20-min of immersive virtual reality on symptoms, affect, and central sensitization in people with chronic back pain
Immersive virtual reality (IVR) is increasingly used as a treatment for chronic pain. In this crossover randomized pilot study, we examined the effect of 10- and 20-min dosages on back pain intensity, affect, and measures of pain sensitization in people with chronic back pain (CBP). Twenty-one people with CBP were seen for two visits of IVR. Participants were randomly assigned to receive either 10- or 20-min of IVR in Visit 1 and the other dosage in Visit 2. Our primary analyses were effect sizes and simple inferential comparisons for pain intensity, affect, fatigue, and measures of pain sensitization assessed using quantitative sensory testing. Overall, IVR had a moderate, significant effect in reducing back pain intensity, negative affect, and painful aftersensations. When dosage was examined, 20-min had a moderate, significant effect on pain while 10-min had a small, non-significant effect, although the between-dosage difference was non-significant. Interestingly, effects were much larger in Visit 1, particularly for 20-min, but this diminished in Visit 2, and both dosages had a smaller effect in Visit 2. We interpret these results to indicate that pain modulation may be associated with novelty and engagement that can attenuate over time if the IVR encounter is not sufficiently engaging. Moreover, that if participants are engaged in a single session, 20-min may be necessary to obtain sufficient competency with IVR, while in subsequent sessions, 10-min of IVR may be sufficient to affect pain
Mars Aeronomy Observer: Report of the Science Working Team
The Mars Aeronomy Observer (MAO) is a candidate follow-on mission to Mars Observer (MO) in the Planetary Observer Program. The four Mariner and two Viking spacecraft sent to Mars between 1965 and 1976 have provided a wealth of information concerning Martian planetology. The Mars Observer, to be launched in 1990, will build on their results by further examining the elemental and mineralogical composition of the surface, the strength and multipolar composition of the planetary magnetic field, the gravitational field and topography, and the circulation of the lower atmosphere. The Mars Aeronomy Observer is intended to address the last major aspects of Martian environment which have yet to be investigated: the upper atmosphere, the ionsphere, and the solar wind interaction region
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