4,351 research outputs found
Direct and generative retrieval of autobiographical memories : the roles of visual imagery and executive processes
Two experiments used a dual task methodology to investigate the role of visual imagery and executive resources in the retrieval of specific autobiographical memories. In Experiment 1, dynamic visual noise led to a reduction in the number of specific memories retrieved in response to both high and low imageability cues, but did not affect retrieval times. In Experiment 2, irrelevant pictures reduced the number of specific memories but only in response to low imageability cues. Irrelevant pictures also increased response times to both high and low imageability cues. The findings are in line with previous work suggesting that disrupting executive resources may impair generative, but not direct, retrieval of autobiographical memories. In contrast, visual distractor tasks appear to impair access to specific autobiographical memories via both the direct and generative retrieval routes, thereby highlighting the potential role of visual imagery in both pathways
Not lost in translation: writing auditorily presented words at study increases correct recognition “at no cost”
© 2016 Taylor & Francis. Previous studies have reported a translation effect in memory, whereby encoding tasks that involve translating between processing domains produce a memory advantage relative to tasks that involve a single domain. We investigated the effects of translation on true and false memories using the Deese/Roediger-McDermott (DRM) procedure [Deese, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology, 58, 17–22; Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, & Cognition, 21, 803–814]. Translation between modalities enhanced correct recognition but had no effect on false recognition. Results are consistent with previous research showing that correct memory can be enhanced “at no cost” in terms of accuracy. Findings are discussed in terms of understanding the relationship between true and false memories produced by the DRM procedure
Measuring the speed of the conscious components of recognition memory: Remembering is faster than knowing.
Three experiments investigated response times (RTs) for remember and know responses in recognition memory. RTs to remember responses were faster than RTs to know responses, regardless of whether the remember–know decision was preceded by an old/new decision (two-step procedure) or was made without a preceding old/new decision (one-step procedure). The finding of faster RTs for R responses was also found when remember–know decisions were made retrospectively. These findings are inconsistent with dual-process models of recognition memory, which predict that recollection is slower and more effortful than familiarity. Word frequency did not influence RTs, but remember responses were faster for words than for nonwords. We argue that the difference in RTs to remember and know responses reflects the time taken to make old/new decisions on the basis of the type of information activated at test
Test-Induced Priming Impairs Source Monitoring Accuracy in the DRM Procedure
Three experiments investigated the effects of test-induced priming (TIP) on false recognition in the Deese/Roediger-McDermott procedure. In Experiment 1, TIP significantly increased false recognition for participants who made old/new decisions at test but not for participants who made remember/know judgements or were given diagnostic information to help them avoid false recognition. In Experiment 2, a TIP effect was observed with old/new recognition but not when participants were required to remember whether study items were spoken by a male or a female. In Experiment 3, false recognition increased when critical lures were preceded by ten studied items but not when preceded by five studied and five unstudied items from the same list. These findings suggest that TIP increases false recognition by disrupting source monitoring processes
Non-equilibrium structural phase transitions of the vortex lattice in MgB2
We have studied non-equilibrium phase transitions in the vortex lattice in
superconducting MgB2, where metastable states are observed in connection with
an intrinsically continuous rotation transition. Using small-angle neutron
scattering and a stop-motion technique, we investigated the manner in which the
metastable vortex lattice returns to the equilibrium state under the influence
of an ac magnetic field. This shows a qualitative difference between the
supercooled case which undergoes a discontinuous transition, and the
superheated case where the transition to the equilibrium state is continuous.
In both cases the transition may be described by an an activated process, with
an activation barrier that increases as the metastable state is suppressed, as
previously reported for the supercooled vortex lattice [E. R. Louden et al.,
Phys. Rev. B 99, 060502(R) (2019)]. Separate preparations of superheated
metastable vortex lattices with different domain populations showed an
identical transition towards the equilibrium state. This provides further
evidence that the vortex lattice metastability, and the kinetics associated
with the transition to the equilibrium state, is governed by nucleation and
growth of domains and the associated domain boundaries.Comment: 27 pages, 10 figures. arXiv admin note: text overlap with
arXiv:1812.0597
Nutritive value of forage legumes used for grazing and silage
peer-reviewedLegume forages have an important position in ruminant production in Western Europe
and with further development can play an even larger role. Red clover for silage and white
clover in grazed swards lead to enhanced growth rate and milk yield in comparison with
pure grasses. Much of the production benefit of these legumes relates to enhanced intake
since digestibilities are not markedly different to grasses. The higher intake of legume
silages reflects differences in the cell structure of legume plants which combined with
high fermentation rates means that they break down into small particles in the rumen,
and leave the rumen more rapidly than perennial ryegrass. Ease of ingestion leads to
high rates of intake, which explains higher intakes for grazed legumes. A further benefit
of legumes is the reduced rate of decline in digestibility with advancing maturity. Whilst
legumes have limited effects on gross milk composition or carcass characteristics, there
are marked increases in levels of beneficial n−3 PUFA. Legumes have often led to a reduction
in methane production from the rumen and again, this relates to both physical and
chemical differences between forage species. The high rates of release of soluble protein
and of breakdown to small particles from clovers and lucerne is associated with susceptibility
to bloat, which is a limitation to further exploitation in grazing systems. The high
concentration of rapidly degraded protein in legumes also leads to inefficient utilisation
of dietary N and increased urinary N output. Research with tanniniferous forages, such
as birdsfoot trefoil and sulla, demonstrates the potential for future legumes with reduced
environmental and health effects, though these particular forage legumes are not well
adapted to temperate regions of Western Europe that are the focus of this review
Distinct vortex-glass phases in YbRhSn at high and low magnetic fields
The vortex lattice (VL) in the mixed state of the stannide superconductor
YbRhSn has been studied using small-angle neutron scattering
(SANS). The field dependencies of the normalized longitudinal and transverse
correlation lengths of the VL, and , reveal two
distinct anomalies that are associated with vortex-glass phases below
~~700~G and above ~~1.7~T ( is the
intervortex distance). At high fields, around 1.7~T, the longitudinal
correlation decreases abruptly with increasing fields indicating a weakening
(but not a complete destruction) of the VL due to a phase transition into a
glassy phase, below (1.8 K)~~2.5~T. and
, gradually decrease for decreasing fields of strengths less than
1~T and tend towards zero. The shear elastic modulus and the tilting
elastic modulus vanish at a critical field ~~700~G,
providing evidence for a disorder-induced transition into a vortex-glass. A
'ring' of scattered intensity is observed for fields lower than 700~G, ,
~=~135~G~~~~700~G. This low-field phenomenon is
of different nature than the one observed at high fields, where but
not , decreases abruptly to an intermediate value
The Absence of Vortex Lattice Melting in a Conventional Superconductor
The state of the vortex lattice extremely close to the superconducting to
normal transition in an applied magnetic field is investigated in high purity
niobium. We observe that thermal fluctuations of the order parameter broaden
the superconducting to normal transition into a crossover but no sign of a
first order vortex lattice melting transition is detected in measurements of
the heat capacity or the small angle neutron scattering (SANS) intensity.
Direct observation of the vortices via SANS always finds a well ordered vortex
lattice. The fluctuation broadening is considered in terms of the Lowest Landau
Level theory of critical fluctuations and scaling is found to occur over a
large H_{c2}(T) range
Metastable Vortex Lattice Phases in Superconducting MgB2
The vortex lattice (VL) symmetry and orientation in clean type-II
superconductors depends sensitively on the host material anisotropy, vortex
density and temperature, frequently leading to rich phase diagrams. Typically,
a well-ordered VL is taken to imply a ground state configuration for the
vortex-vortex interaction. Using neutron scattering we studied the VL in MgB2
for a number of field-temperature histories, discovering an unprecedented
degree of metastability in connection with a known, second-order rotation
transition. This allows, for the first time, structural studies of a
well-ordered, non-equilibrium VL. While the mechanism responsible for the
longevity of the metastable states is not resolved, we speculate it is due to a
jamming of VL domains, preventing a rotation to the ground state orientation.Comment: Main paper: 5 pages, 4 figures. Supplementary material: 3 pages, 7
figure
- …
