344 research outputs found
Interoceptive cardiac signals selectively enhance fear memories
Fear is coupled to states of physiological arousal. We tested how learning and memory of threat, specifically conditioned fear, is influenced by interoceptive signals. Forty healthy individuals were exposed to two threat (conditioned stimuli [CS+], paired with electrocutaneous shocks) and two safety (CS-) stimuli, time-locked to either cardiac ventricular systole (when arterial baroreceptors signal cardiovascular arousal to brainstem), or diastole (when these afferent signals are quiescent). Threat learning was indexed objectively using skin conductance responses (SCRs). During acquisition of threat contingencies, cardiac effects dominated: Stimuli (both CS+ and CS-) presented at systole evoked greater SCR responses, relative to stimuli (both CS+ and CS-) presented at diastole. This difference was amplified in more anxious individuals. Learning of conditioned fear was established by the end of the acquisition phase, which was followed by an extinction phase when unpaired CSs were presented at either the same or switched cardiac contingencies. One day later, electrocutaneous shocks triggered the reinstatement of fear responses. Subsequent presentation of stimuli previously encoded at systole evoked higher SCRs. Moreover, only those participants for whom stimuli had the same cardiac-contingency over both acquisition and extinction phases retained conditioned fear memory (i.e., CS+ > CS-). Our findings reveal two important cardiac afferent effects on threat learning and memory: 1) Cardiac signals bias processing toward threat; and 2) cardiac signals are a context for fear memory; altering this context can disrupt the memory. These observations suggest how threat reactivity may be reinforced and maintained by both acute and enduring states of cardiac arousal. (PsycInfo Database Record (c) 2020 APA, all rights reserved)
The Filter Detection Task for measurement of breathing-related interoception and metacognition
The study of the brainâs processing of sensory inputs from within the body (âinteroceptionâ) has been gaining rapid popularity in neuroscience, where interoceptive disturbances are thought to exist across a wide range of chronic physiological and psychological conditions. Here we present a task and analysis procedure to quantify specific dimensions of breathing-related interoception, including interoceptive sensitivity, decision bias, metacognitive bias, and metacognitive performance. Two major developments address some of the challenges presented by low trial numbers in interoceptive experiments: (i) a novel adaptive algorithm to maintain task performance at 70â75% accuracy; (ii) an extended hierarchical metacognitive model to estimate regression parameters linking metacognitive performance to relevant (e.g. clinical) variables. We demonstrate the utility of the task and analysis developments, using both simulated data and three empirical datasets. This methodology represents an important step towards accurately quantifying interoceptive dimensions from a simple experimental procedure that is compatible with clinical settings
The Evolution of Expressing and Exchanging Cyber-Investigation Information in a Standardized Form
The growing number of investigations involving digital traces from various data sources is driving the demand for a standard way to represent and exchange pertinent information. Enabling automated combination and correlation of cyber-investigation information from multiple systems or organizations enables more efficient and comprehensive analysis, reducing the risk of mistakes and missed opportunities. These needs are being met by the evolving open-source, community-developed specification language called CASE, the Cyber-investigation Analysis Standard Expression. CASE leverages the Unified Cyber Ontology (UCO), which abstracts and expresses concepts that are common across multiple domains. This paper introduces CASE and UCO, explaining how they improve upon prior related work. The value of fully-structured data, representing provenance, and action lifecycles are discussed. The guiding principles of CASE and UCO are presented, and illustrative examples of CASE are provided using the default JSON-LD serialization
Diffractive Dijet Production at sqrt(s)=630 and 1800 GeV at the Fermilab Tevatron
We report a measurement of the diffractive structure function of
the antiproton obtained from a study of dijet events produced in association
with a leading antiproton in collisions at GeV at the
Fermilab Tevatron. The ratio of at GeV to
obtained from a similar measurement at GeV is compared with
expectations from QCD factorization and with theoretical predictions. We also
report a measurement of the (-Pomeron) and ( of parton in
Pomeron) dependence of at GeV. In the region
, GeV and , is
found to be of the form , which obeys
- factorization.Comment: LaTeX, 9 pages, Submitted to Phys. Rev. Letter
Search for Kaluza-Klein Graviton Emission in Collisions at TeV using the Missing Energy Signature
We report on a search for direct Kaluza-Klein graviton production in a data
sample of 84 of \ppb collisions at = 1.8 TeV, recorded
by the Collider Detector at Fermilab. We investigate the final state of large
missing transverse energy and one or two high energy jets. We compare the data
with the predictions from a -dimensional Kaluza-Klein scenario in which
gravity becomes strong at the TeV scale. At 95% confidence level (C.L.) for
=2, 4, and 6 we exclude an effective Planck scale below 1.0, 0.77, and 0.71
TeV, respectively.Comment: Submitted to PRL, 7 pages 4 figures/Revision includes 5 figure
Measurement of the Forward-Backward Asymmetry in the B -> K(*) mu+ mu- Decay and First Observation of the Bs -> phi mu+ mu- Decay
We reconstruct the rare decays , , and in a data sample
corresponding to collected in collisions at
by the CDF II detector at the Fermilab Tevatron
Collider. Using and decays we report the branching ratios. In addition, we report
the measurement of the differential branching ratio and the muon
forward-backward asymmetry in the and decay modes, and the
longitudinal polarization in the decay mode with respect to the squared
dimuon mass. These are consistent with the theoretical prediction from the
standard model, and most recent determinations from other experiments and of
comparable accuracy. We also report the first observation of the {\mathcal{B}}(B^0_s \to
\phi\mu^+\mu^-) = [1.44 \pm 0.33 \pm 0.46] \times 10^{-6}27 \pm 6B^0_s$ decay observed.Comment: 7 pages, 2 figures, 3 tables. Submitted to Phys. Rev. Let
A Study of B0 -> J/psi K(*)0 pi+ pi- Decays with the Collider Detector at Fermilab
We report a study of the decays B0 -> J/psi K(*)0 pi+ pi-, which involve the
creation of a u u-bar or d d-bar quark pair in addition to a b-bar -> c-bar(c
s-bar) decay. The data sample consists of 110 1/pb of p p-bar collisions at
sqrt{s} = 1.8 TeV collected by the CDF detector at the Fermilab Tevatron
collider during 1992-1995. We measure the branching ratios to be BR(B0 -> J/psi
K*0 pi+ pi-) = (8.0 +- 2.2 +- 1.5) * 10^{-4} and BR(B0 -> J/psi K0 pi+ pi-) =
(1.1 +- 0.4 +- 0.2) * 10^{-3}. Contributions to these decays are seen from
psi(2S) K(*)0, J/psi K0 rho0, J/psi K*+ pi-, and J/psi K1(1270)
Search for a New Heavy Gauge Boson Wprime with Electron + missing ET Event Signature in ppbar collisions at sqrt(s)=1.96 TeV
We present a search for a new heavy charged vector boson decaying
to an electron-neutrino pair in collisions at a center-of-mass
energy of 1.96\unit{TeV}. The data were collected with the CDF II detector
and correspond to an integrated luminosity of 5.3\unit{fb}^{-1}. No
significant excess above the standard model expectation is observed and we set
upper limits on . Assuming standard
model couplings to fermions and the neutrino from the boson decay to
be light, we exclude a boson with mass less than
1.12\unit{TeV/}c^2 at the 95\unit{%} confidence level.Comment: 7 pages, 2 figures Submitted to PR
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