WorldWideScience

Sample records for multivalued memory effects

  1. Multi-Valued Associative Memory Neural Network

    Institute of Scientific and Technical Information of China (English)

    修春波; 刘向东; 张宇河

    2003-01-01

    A novel learning method for multi-valued associative memory network is introduced, which is based on Hebb rule, but utilizes more information. According to the current probe vector, the connection weights matrix could be chosen dynamically. Double-valued and multi-valued associative memory are all realized in our simulation experiment. The experimental results show that the method could enhance the associative success rate.

  2. A novel network of chaotic elements and its application in multi-valued associative memory

    International Nuclear Information System (INIS)

    Xiu Chunbo; Liu Xiangdong; Tang Yunyu; Zhang Yuhe

    2004-01-01

    We give a novel chaotic element model whose activation function composed of Gauss and Sigmoid function. It is shown that the model may exhibit a complex dynamic behavior. The most significant bifurcation processes, leading to chaos, are investigated through the computation of the Lyapunov exponents. Based on this model, we propose a novel network of chaotic elements, which can be applied in associative memory, and then investigate its dynamic behavior. It is worth noting that multi-valued associative memory can also be realized by this network

  3. Multi-valued fields

    CERN Document Server

    Ershov, Yuri L

    2001-01-01

    For more than 30 years, the author has studied the model-theoretic aspects of the theory of valued fields and multi-valued fields. Many of the key results included in this book were obtained by the author whilst preparing the manuscript. Thus the unique overview of the theory, as developed in the book, has been previously unavailable. The book deals with the theory of valued fields and mutli-valued fields. The theory of Prüfer rings is discussed from the `geometric' point of view. The author shows that by introducing the Zariski topology on families of valuation rings, it is possible to distinguish two important subfamilies of Prüfer rings that correspond to Boolean and near Boolean families of valuation rings. Also, algebraic and model-theoretic properties of multi-valued fields with near Boolean families of valuation rings satisfying the local-global principle are studied. It is important that this principle is elementary, i.e., it can be expressed in the language of predicate calculus. The most important...

  4. Anti-inflammatory effects of reactive oxygen species - a multi-valued logical model validated by formal concept analysis.

    Science.gov (United States)

    Wollbold, Johannes; Jaster, Robert; Müller, Sarah; Rateitschak, Katja; Wolkenhauer, Olaf

    2014-09-24

    Recent findings suggest that in pancreatic acinar cells stimulated with bile acid, a pro-apoptotic effect of reactive oxygen species (ROS) dominates their effect on necrosis and spreading of inflammation. The first effect presumably occurs via cytochrome C release from the inner mitochondrial membrane. A pro-necrotic effect - similar to the one of Ca2+ - can be strong opening of mitochondrial pores leading to breakdown of the membrane potential, ATP depletion, sustained Ca2+ increase and premature activation of digestive enzymes. To explain published data and to understand ROS effects during the onset of acute pancreatitis, a model using multi-valued logic is constructed. Formal concept analysis (FCA) is used to validate the model against data as well as to analyze and visualize rules that capture the dynamics. Simulations for two different levels of bile stimulation and for inhibition or addition of antioxidants reproduce the qualitative behaviour shown in the experiments. Based on reported differences of ROS production and of ROS induced pore opening, the model predicts a more uniform apoptosis/necrosis ratio for higher and lower bile stimulation in liver cells than in pancreatic acinar cells. FCA confirms that essential dynamical features of the data are captured by the model. For instance, high necrosis always occurs together with at least a medium level of apoptosis. At the same time, FCA helps to reveal subtle differences between data and simulations. The FCA visualization underlines the protective role of ROS against necrosis. The analysis of the model demonstrates how ROS and decreased antioxidant levels contribute to apoptosis. Studying the induction of necrosis via a sustained Ca2+ increase, we implemented the commonly accepted hypothesis of ATP depletion after strong bile stimulation. Using an alternative model, we demonstrate that this process is not necessary to generate the dynamics of the measured variables. Opening of plasma membrane channels could

  5. Field transformations to multivalued fields

    Energy Technology Data Exchange (ETDEWEB)

    Kleinert, H [Institut fuer Theoretische Physik, Arnimallee 14, D-14195 Berlin (Germany)

    2007-05-15

    Changes of field variables may lead to multivalued fields which do not satisfy the Schwarz integrability conditions. Their quantum field theory needs special care as is shown in an application to the superfluid and superconducting phase transitions.

  6. Nonlinear Elliptic Differential Equations with Multivalued Nonlinearities

    Indian Academy of Sciences (India)

    In this paper we study nonlinear elliptic boundary value problems with monotone and nonmonotone multivalued nonlinearities. First we consider the case of monotone nonlinearities. In the first result we assume that the multivalued nonlinearity is defined on all R R . Assuming the existence of an upper and of a lower ...

  7. Multi-Valued Spin Switch in a Semiconductor Microcavity

    Science.gov (United States)

    Paraïso, T. K.; Wouters, M.; Léger, Y.; Morier-Genoud, F.; Deveaudhyphen; Plédran, B.

    2011-12-01

    In this work, we report on the first realization of multi-valued spin switching in the solid-state. We investigate the physics of spinor bistability with microcavity polaritons in a trap. Spinor interactions lead to special bistability regimes with decoupled thresholds for spin-up and spin-down polaritons. This allows us to establish state-of-the-art spin switching operations. We evidence polarization hysteresis and determine appropriate conditions to achieve spin multistability. For a given excitation condition, three stable spin states coexist for the system. These results open new pathways for the development of innovative spin-based logic gates and memory devices.

  8. Multiple negative differential resistance devices with ultra-high peak-to-valley current ratio for practical multi-valued logic and memory applications

    Science.gov (United States)

    Shin, Sunhae; Rok Kim, Kyung

    2015-06-01

    In this paper, we propose a novel multiple negative differential resistance (NDR) device with ultra-high peak-to-valley current ratio (PVCR) over 106 by combining tunnel diode with a conventional MOSFET, which suppresses the valley current with transistor off-leakage level. Band-to-band tunneling (BTBT) in tunnel junction provides the first peak, and the second peak and valley are generated from the suppression of diffusion current in tunnel diode by the off-state MOSFET. The multiple NDR curves can be controlled by doping concentration of tunnel junction and the threshold voltage of MOSFET. By using complementary multiple NDR devices, five-state memory is demonstrated only with six transistors.

  9. Multivalued synchronization by Poincaré coupling

    Science.gov (United States)

    Ontañón-García, L. J.; Campos-Cantón, E.; Femat, R.; Campos-Cantón, I.; Bonilla-Marín, M.

    2013-10-01

    This work presents multivalued chaotic synchronization via coupling based on the Poincaré plane. The coupling is carried out by an underdamped signal, triggered every crossing event of the trajectory of the master system through a previously defined Poincaré plane. A master-slave system is explored, and the synchronization between the systems is detected via the auxiliary system approach and the maximum conditional Lyapunov exponent. Due to the response to specific conditions two phenomena may be obtained: univalued and multivalued synchronization. Since the Lyapunov exponent is not enough to detect these two phenomena, the distance between the pieces of trajectories of the slave and auxiliary systems with different initial conditions is also used as a tool for the detection of multivalued synchronization. Computer simulations using the benchmark chaotic systems of Lorenz and Rössler are used to exemplify the approach proposed.

  10. Multivalued stochastic delay differential equations and related ...

    African Journals Online (AJOL)

    We study the existence and uniqueness of a solution for the multivalued stochastic differential equation with delay (the multivalued term is of subdifferential type):. dX(t) + aφ (X(t))dt ∍ b(t,X(t), Y(t), Z(t)) dt. ⎨ +σ (t, X (t), Y (t), Z (t)) dW (t), t ∈ (s, T). X(t) = ξ (t - s), t ∈ [s - δ, s]. Specify that in this case the coefficients at time t ...

  11. Trinary flip-flops using Savart plate and spatial light modulator for optical computation in multivalued logic

    Science.gov (United States)

    Ghosh, Amal K.; Basuray, Amitabha

    2008-11-01

    The memory devices in multi-valued logic are of most significance in modern research. This paper deals with the implementation of basic memory devices in multi-valued logic using Savart plate and spatial light modulator (SLM) based optoelectronic circuits. Photons are used here as the carrier to speed up the operations. Optical tree architecture (OTA) has been also utilized in the optical interconnection network. We have exploited the advantages of Savart plates, SLMs and OTA and proposed the SLM based high speed JK, D-type and T-type flip-flops in a trinary system.

  12. Dialectical Multivalued Logic and Probabilistic Theory

    Directory of Open Access Journals (Sweden)

    José Luis Usó Doménech

    2017-02-01

    Full Text Available There are two probabilistic algebras: one for classical probability and the other for quantum mechanics. Naturally, it is the relation to the object that decides, as in the case of logic, which algebra is to be used. From a paraconsistent multivalued logic therefore, one can derive a probability theory, adding the correspondence between truth value and fortuity.

  13. Polarization encoded all-optical multi-valued shift operators

    Science.gov (United States)

    Roy, Jitendra Nath; Bhowmik, Panchatapa

    2014-08-01

    Polarization encoded multi-valued (both ternary and quaternary logic) shift operators have been designed using linear optical devices only. There are six ternary and 24 quaternary shift operators in multi-valued system. These are also known as reversible literals. This circuit will be useful in future all-optical multi-valued logic based information processing system. Different states of polarization of light are taken as different logic states.

  14. Model-Checking of Linear-Time Properties in Multi-Valued Systems

    OpenAIRE

    Li, Yongming; Droste, Manfred; Lei, Lihui

    2012-01-01

    In this paper, we study model-checking of linear-time properties in multi-valued systems. Safety property, invariant property, liveness property, persistence and dual-persistence properties in multi-valued logic systems are introduced. Some algorithms related to the above multi-valued linear-time properties are discussed. The verification of multi-valued regular safety properties and multi-valued $\\omega$-regular properties using lattice-valued automata are thoroughly studied. Since the law o...

  15. Variational multi-valued velocity field estimation for transparent sequences

    DEFF Research Database (Denmark)

    Ramírez-Manzanares, Alonso; Rivera, Mariano; Kornprobst, Pierre

    2011-01-01

    Motion estimation in sequences with transparencies is an important problem in robotics and medical imaging applications. In this work we propose a variational approach for estimating multi-valued velocity fields in transparent sequences. Starting from existing local motion estimators, we derive...... a variational model for integrating in space and time such a local information in order to obtain a robust estimation of the multi-valued velocity field. With this approach, we can indeed estimate multi-valued velocity fields which are not necessarily piecewise constant on a layer –each layer can evolve...

  16. Topological fixed point theory of multivalued mappings

    CERN Document Server

    Górniewicz, Lech

    1999-01-01

    This volume presents a broad introduction to the topological fixed point theory of multivalued (set-valued) mappings, treating both classical concepts as well as modern techniques. A variety of up-to-date results is described within a unified framework. Topics covered include the basic theory of set-valued mappings with both convex and nonconvex values, approximation and homological methods in the fixed point theory together with a thorough discussion of various index theories for mappings with a topologically complex structure of values, applications to many fields of mathematics, mathematical economics and related subjects, and the fixed point approach to the theory of ordinary differential inclusions. The work emphasises the topological aspect of the theory, and gives special attention to the Lefschetz and Nielsen fixed point theory for acyclic valued mappings with diverse compactness assumptions via graph approximation and the homological approach. Audience: This work will be of interest to researchers an...

  17. Optimization with Multivalued Mappings Theory, Applications and Algorithms

    CERN Document Server

    Dempe, Stephan

    2006-01-01

    Focussing on optimization problems involving multivalued mappings in constraints or as the objective function, this book includes the formulation of optimality conditions using different kinds of generalized derivatives for set-valued mappings, among the other related topics.

  18. Impulsive evolution inclusions with infinite delay and multivalued jumps

    Directory of Open Access Journals (Sweden)

    Mouffak Benchohra

    2012-08-01

    Full Text Available In this paper we prove the existence of a mild solution for a class of impulsive semilinear evolution differential inclusions with infinite delay and multivalued jumps in a Banach space.

  19. Shape memory effect alloys

    International Nuclear Information System (INIS)

    Koshimizu, S.

    1992-01-01

    Although the pseudo- or super-elasticity phenomena and the shape memory effect were known since the 1940's, the enormous curiosity and the great interest to their practical applications emerged with the development of the NITINOL alloy (Nickel-Titanium Naval Ordance Laboratory) by the NASA during the 1960's. This fact marked the appearance of a new class of materials, popularly known as shape memory effect alloys (SMEA). The objective of this work is to present a state-of-the-art of the development and applications for the SMEA. (E.O.)

  20. General Large Deviations and Functional Iterated Logarithm Law for Multivalued Stochastic Differential Equations

    OpenAIRE

    Ren, Jiagang; Wu, Jing; Zhang, Hua

    2015-01-01

    In this paper, we prove a large deviation principle of Freidlin-Wentzell's type for the multivalued stochastic differential equations. As an application, we derive a functional iterated logarithm law for the solutions of multivalued stochastic differential equations.

  1. Existence and Stability of Solutions for Implicit Multivalued Vector Equilibrium Problems

    Directory of Open Access Journals (Sweden)

    Li Qiuying

    2011-01-01

    Full Text Available A class of implicit multivalued vector equilibrium problems is studied. By using the generalized Fan-Browder fixed point theorem, some existence results of solutions for the implicit multivalued vector equilibrium problems are obtained under some suitable assumptions. Moreover, a stability result of solutions for the implicit multivalued vector equilibrium problems is derived. These results extend and unify some recent results for implicit vector equilibrium problems, multivalued vector variational inequality problems, and vector variational inequality problems.

  2. Multi-valued LSI/VLSI logic design

    Science.gov (United States)

    Santrakul, K.

    A procedure for synthesizing any large complex logic system, such as LSI and VLSI integrated circuits is described. This scheme uses Multi-Valued Multi-plexers (MVMUX) as the basic building blocks and the tree as the structure of the circuit realization. Simple built-in test circuits included in the network (the main current), provide a thorough functional checking of the network at any time. In brief, four major contributions are made: (1) multi-valued Algorithmic State Machine (ASM) chart for describing an LSI/VLSI behavior; (2) a tree-structured multi-valued multiplexer network which can be obtained directly from an ASM chart; (3) a heuristic tree-structured synthesis method for realizing any combinational logic with minimal or nearly-minimal MVMUX; and (4) a hierarchical design of LSI/VLSI with built-in parallel testing capability.

  3. Linear deformations of discrete groups and constructions of multivalued groups

    International Nuclear Information System (INIS)

    Yagodovskii, Petr V

    2000-01-01

    We construct deformations of discrete multivalued groups described as special deformations of their group algebras in the class of finite-dimensional associative algebras. We show that the deformations of ordinary groups producing multivalued groups are defined by cocycles with coefficients in the group algebra of the original group and obtain classification theorems on these deformations. We indicate a connection between the linear deformations of discrete groups introduced in this paper and the well-known constructions of multivalued groups. We describe the manifold of three-dimensional associative commutative algebras with identity element, fixed basis, and a constant number of values. The group algebras of n-valued groups of order three (three-dimensional n-group algebras) form a discrete set in this manifold

  4. Logic-type Schmitt circuit using multi-valued gates

    Science.gov (United States)

    Wakui, M.; Tanaka, M.

    Logic-type Schmitt circuits (LTSCs) proposed in this paper by author's proposal are a new detector for a multi-valued multi-threshold logic circuit, and it realizes the high resolution with a little hysteresis or the high noise margin. The detector consists of the combinations of the multi-valued gates (MVGs) and a positive reaction device (PRD), and each circuit can be realized by the conventional elements. This paper shows their practical circuits, and describes the regions and the conditions for their operation.

  5. Topological characteristics of multi-valued maps and Lipschitzian functionals

    International Nuclear Information System (INIS)

    Klimov, V S

    2008-01-01

    This paper deals with the operator inclusion O element of F(x)+N Q (x), where F is a multi-valued map of monotonic type from a reflexive space V to its conjugate V * and N Q is the cone normal to the closed set Q, which, generally speaking, is not convex. To estimate the number of solutions of this inclusion we introduce topological characteristics of multi-valued maps and Lipschitzian functionals that have the properties of additivity and homotopy invariance. We prove some infinite-dimensional versions of the Poincare-Hopf theorem

  6. Multi-valued and Fuzzy Logic Realization using TaOx Memristive Devices.

    Science.gov (United States)

    Bhattacharjee, Debjyoti; Kim, Wonjoo; Chattopadhyay, Anupam; Waser, Rainer; Rana, Vikas

    2018-01-08

    Among emerging non-volatile storage technologies, redox-based resistive switching Random Access Memory (ReRAM) is a prominent one. The realization of Boolean logic functionalities using ReRAM adds an extra edge to this technology. Recently, 7-state ReRAM devices were used to realize ternary arithmetic circuits, which opens up the computing space beyond traditional binary values. In this manuscript, we report realization of multi-valued and fuzzy logic operators with a representative application using ReRAM devices. Multi-valued logic (MVL), such as Łukasiewicz logic generalizes Boolean logic by allowing more than two truth values. MVL also permits operations on fuzzy sets, where, in contrast to standard crisp logic, an element is permitted to have a degree of membership to a given set. Fuzzy operations generally model human reasoning better than Boolean logic operations, which is predominant in current computing technologies. When the available information for the modelling of a system is imprecise and incomplete, fuzzy logic provides an excellent framework for the system design. Practical applications of fuzzy logic include, industrial control systems, robotics, and in general, design of expert systems through knowledge-based reasoning. Our experimental results show, for the first time, that it is possible to model fuzzy logic natively using multi-state memristive devices.

  7. Common fixed points of single-valued and multivalued maps

    Directory of Open Access Journals (Sweden)

    Yicheng Liu

    2005-01-01

    Full Text Available We define a new property which contains the property (EA for a hybrid pair of single- and multivalued maps and give some new common fixed point theorems under hybrid contractive conditions. Our results extend previous ones. As an application, we give a partial answer to the problem raised by Singh and Mishra.

  8. Approximate Compilation of Constraints into Multivalued Decision Diagrams

    DEFF Research Database (Denmark)

    Hadzic, Tarik; Hooker, John N.; O’Sullivan, Barry

    2008-01-01

    We present an incremental refinement algorithm for approximate compilation of constraint satisfaction models into multivalued decision diagrams (MDDs). The algorithm uses a vertex splitting operation that relies on the detection of equivalent paths in the MDD. Although the algorithm is quite gene...

  9. Multi-valued simulation and abstraction using lattice operations

    NARCIS (Netherlands)

    Vijzelaar, Stefan; Fokkink, W.J.

    2017-01-01

    Abstractions can cause spurious results, which need to be verified in the concrete system to gain conclusive results. Verification based on a multi-valued logic can distinguish between conclusive and inconclusive results, provides increased precision, and allows for encoding additional information

  10. Multi-Valued Modal Fixed Point Logics for Model Checking

    Science.gov (United States)

    Nishizawa, Koki

    In this paper, I will show how multi-valued logics are used for model checking. Model checking is an automatic technique to analyze correctness of hardware and software systems. A model checker is based on a temporal logic or a modal fixed point logic. That is to say, a system to be checked is formalized as a Kripke model, a property to be satisfied by the system is formalized as a temporal formula or a modal formula, and the model checker checks that the Kripke model satisfies the formula. Although most existing model checkers are based on 2-valued logics, recently new attempts have been made to extend the underlying logics of model checkers to multi-valued logics. I will summarize these new results.

  11. Fixed Points of Multivalued Contractive Mappings in Partial Metric Spaces

    Directory of Open Access Journals (Sweden)

    Abdul Rahim Khan

    2014-01-01

    Full Text Available The aim of this paper is to present fixed point results of multivalued mappings in the framework of partial metric spaces. Some examples are presented to support the results proved herein. Our results generalize and extend various results in the existing literature. As an application of our main result, the existence and uniqueness of bounded solution of functional equations arising in dynamic programming are established.

  12. Generalized Semiflows and Chaos in Multivalued Dynamical Systems

    Czech Academy of Sciences Publication Activity Database

    Beran, Zdeněk; Čelikovský, Sergej

    2012-01-01

    Roč. 26, č. 25 (2012), 1246016-1-1246016-11 ISSN 0217-9792 R&D Projects: GA ČR(CZ) GAP103/12/1794 Institutional support: RVO:67985556 Keywords : Multivalued dynamical systems * chaos * differential inclusions Subject RIV: BC - Control Systems Theory Impact factor: 0.358, year: 2012 http://library.utia.cas.cz/separaty/2012/TR/beran-0380290.pdf

  13. Efficient Multi-Valued Bounded Model Checking for LTL over Quasi-Boolean Algebras

    OpenAIRE

    Andrade, Jefferson O.; Kameyama, Yukiyoshi

    2012-01-01

    Multi-valued Model Checking extends classical, two-valued model checking to multi-valued logic such as Quasi-Boolean logic. The added expressivity is useful in dealing with such concepts as incompleteness and uncertainty in target systems, while it comes with the cost of time and space. Chechik and others proposed an efficient reduction from multi-valued model checking problems to two-valued ones, but to the authors' knowledge, no study was done for multi-valued bounded model checking. In thi...

  14. Diffusion processes and memory effects

    International Nuclear Information System (INIS)

    Mokshin, Anatolii V; Yulmetyev, Renat M; Haenggi, Peter

    2005-01-01

    We report the results of the numerical estimation of statistical memory effects in diffusion for two various systems: Lennard-Jones fluids and the model of the Brownian particle in a one-dimensional harmonic lattice. We have found the relation between the diffusion coefficient and the non-Markovity parameter, which is linear for the Lennard-Jones systems in liquid state. The relation between the memory measure and the excess entropy is also discussed here

  15. An improved multi-value cellular automata model for heterogeneous bicycle traffic flow

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Sheng [College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310058 China (China); Qu, Xiaobo [Griffith School of Engineering, Griffith University, Gold Coast, 4222 Australia (Australia); Xu, Cheng [Department of Transportation Management Engineering, Zhejiang Police College, Hangzhou, 310053 China (China); College of Transportation, Jilin University, Changchun, 130022 China (China); Ma, Dongfang, E-mail: mdf2004@zju.edu.cn [Ocean College, Zhejiang University, Hangzhou, 310058 China (China); Wang, Dianhai [College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310058 China (China)

    2015-10-16

    This letter develops an improved multi-value cellular automata model for heterogeneous bicycle traffic flow taking the higher maximum speed of electric bicycles into consideration. The update rules of both regular and electric bicycles are improved, with maximum speeds of two and three cells per second respectively. Numerical simulation results for deterministic and stochastic cases are obtained. The fundamental diagrams and multiple states effects under different model parameters are analyzed and discussed. Field observations were made to calibrate the slowdown probabilities. The results imply that the improved extended Burgers cellular automata (IEBCA) model is more consistent with the field observations than previous models and greatly enhances the realism of the bicycle traffic model. - Highlights: • We proposed an improved multi-value CA model with higher maximum speed. • Update rules are introduced for heterogeneous bicycle traffic with maximum speed 2 and 3 cells/s. • Simulation results of the proposed model are consistent with field bicycle data. • Slowdown probabilities of both regular and electric bicycles are calibrated.

  16. An improved multi-value cellular automata model for heterogeneous bicycle traffic flow

    International Nuclear Information System (INIS)

    Jin, Sheng; Qu, Xiaobo; Xu, Cheng; Ma, Dongfang; Wang, Dianhai

    2015-01-01

    This letter develops an improved multi-value cellular automata model for heterogeneous bicycle traffic flow taking the higher maximum speed of electric bicycles into consideration. The update rules of both regular and electric bicycles are improved, with maximum speeds of two and three cells per second respectively. Numerical simulation results for deterministic and stochastic cases are obtained. The fundamental diagrams and multiple states effects under different model parameters are analyzed and discussed. Field observations were made to calibrate the slowdown probabilities. The results imply that the improved extended Burgers cellular automata (IEBCA) model is more consistent with the field observations than previous models and greatly enhances the realism of the bicycle traffic model. - Highlights: • We proposed an improved multi-value CA model with higher maximum speed. • Update rules are introduced for heterogeneous bicycle traffic with maximum speed 2 and 3 cells/s. • Simulation results of the proposed model are consistent with field bicycle data. • Slowdown probabilities of both regular and electric bicycles are calibrated

  17. Hysteretic memory effects in disordered magnets

    OpenAIRE

    Katzgraber, Helmut G.; Zimanyi, Gergely T.

    2005-01-01

    We study the return point as well as the complementary point memory effects numerically with paradigmatic models for random magnets and show that already simple systems with Ising spin symmetry can reproduce the experimental results of Pierce et al. where both memory effects become more pronounced for increasing disorder and return point memory is always better than complementary point memory.

  18. Multi-valued logic in breast cancer detection.

    Science.gov (United States)

    Boiculese, L V; Dimitriu, G

    2003-01-01

    The aim of this paper is to determine the type of the breast cancer disease. The two classes of separation are malignant respectively benign. A multi-valued logic system (fuzzy system) was develop and applied in this classification. The system uses nine attributes as inputs that were scaled with an integer value in the range between 1 and 10. The attributes represent: 1. Clump Thickness, 2. Uniformity of Cell Size, 3. Uniformity of Cell Shape, 4. Marginal Adhesion, 5. Single Epithelial Cell Size, 6. Bare Nuclei, 7. Bland Chromatin, 8. Normal Nucleoli, 9. Mitoses. After training the system managed to get a good detection with an error less than 5%.

  19. Memory effects in turbulent diffusion

    International Nuclear Information System (INIS)

    Zagorodny, A.G.; Weiland, J.; Wilhelmsson, H.

    1993-01-01

    A non-Markovian approach is proposed for the derivation of the diffusion coefficient of saturated turbulence. A memory term accounting for nonlocal coherence effects is introduced in a new attempt to describe the transition between weak and strong turbulence. The result compares favourably with recent experiments as well as mode coupling simulations of fusion plasmas. (14 refs.)

  20. Multi-Valued Logic Gates, Continuous Sensitivity, Reversibility, and Threshold Functions

    OpenAIRE

    İlhan, Aslı Güçlükan; Ünlü, Özgün

    2016-01-01

    We define an invariant of a multi-valued logic gate by considering the number of certain threshold functions associated with the gate. We call this invariant the continuous sensitivity of the gate. We discuss a method for analysing continuous sensitivity of a multi-valued logic gate by using experimental data about the gate. In particular, we will show that this invariant provides a lower bound for the sensitivity of a boolean function considered as a multi-valued logic gate. We also discuss ...

  1. Stress Effects on Multiple Memory System Interactions

    OpenAIRE

    Ness, Deborah; Calabrese, Pasquale

    2016-01-01

    Extensive behavioural, pharmacological, and neurological research reports stress effects on mammalian memory processes. While stress effects on memory quantity have been known for decades, the influence of stress on multiple memory systems and their distinct contributions to the learning process have only recently been described. In this paper, after summarizing the fundamental biological aspects of stress/emotional arousal and recapitulating functionally and anatomically distinct memory syst...

  2. Averaged multivalued solutions and time discretization for conservation laws

    International Nuclear Information System (INIS)

    Brenier, Y.

    1985-01-01

    It is noted that the correct shock solutions can be approximated by averaging in some sense the multivalued solution given by the method of characteristics for the nonlinear scalar conservation law (NSCL). A time discretization for the NSCL equation based on this principle is considered. An equivalent analytical formulation is shown to lead quite easily to a convergence result, and a third formulation is introduced which can be generalized for the systems of conservation laws. Various numerical schemes are constructed from the proposed time discretization. The first family of schemes is obtained by using a spatial grid and projecting the results of the time discretization. Many known schemes are then recognized (mainly schemes by Osher, Roe, and LeVeque). A second way to discretize leads to a particle scheme without space grid, which is very efficient (at least in the scalar case). Finally, a close relationship between the proposed method and the Boltzmann type schemes is established. 14 references

  3. Synthesis of multivalued quantum logic circuits by elementary gates

    Science.gov (United States)

    Di, Yao-Min; Wei, Hai-Rui

    2013-01-01

    We propose the generalized controlled X (gcx) gate as the two-qudit elementary gate, and based on Cartan decomposition, we also give the one-qudit elementary gates. Then we discuss the physical implementation of these elementary gates and show that it is feasible with current technology. With these elementary gates many important qudit quantum gates can be synthesized conveniently. We provide efficient methods for the synthesis of various kinds of controlled qudit gates and greatly simplify the synthesis of existing generic multi-valued quantum circuits. Moreover, we generalize the quantum Shannon decomposition (QSD), the most powerful technique for the synthesis of generic qubit circuits, to the qudit case. A comparison of ququart (d=4) circuits and qubit circuits reveals that using ququart circuits may have an advantage over the qubit circuits in the synthesis of quantum circuits.

  4. Stress Effects on Multiple Memory System Interactions

    Science.gov (United States)

    Ness, Deborah; Calabrese, Pasquale

    2016-01-01

    Extensive behavioural, pharmacological, and neurological research reports stress effects on mammalian memory processes. While stress effects on memory quantity have been known for decades, the influence of stress on multiple memory systems and their distinct contributions to the learning process have only recently been described. In this paper, after summarizing the fundamental biological aspects of stress/emotional arousal and recapitulating functionally and anatomically distinct memory systems, we review recent animal and human studies exploring the effects of stress on multiple memory systems. Apart from discussing the interaction between distinct memory systems in stressful situations, we will also outline the fundamental role of the amygdala in mediating such stress effects. Additionally, based on the methods applied in the herein discussed studies, we will discuss how memory translates into behaviour. PMID:27034845

  5. Stress Effects on Multiple Memory System Interactions

    Directory of Open Access Journals (Sweden)

    Deborah Ness

    2016-01-01

    Full Text Available Extensive behavioural, pharmacological, and neurological research reports stress effects on mammalian memory processes. While stress effects on memory quantity have been known for decades, the influence of stress on multiple memory systems and their distinct contributions to the learning process have only recently been described. In this paper, after summarizing the fundamental biological aspects of stress/emotional arousal and recapitulating functionally and anatomically distinct memory systems, we review recent animal and human studies exploring the effects of stress on multiple memory systems. Apart from discussing the interaction between distinct memory systems in stressful situations, we will also outline the fundamental role of the amygdala in mediating such stress effects. Additionally, based on the methods applied in the herein discussed studies, we will discuss how memory translates into behaviour.

  6. Stress Effects on Multiple Memory System Interactions.

    Science.gov (United States)

    Ness, Deborah; Calabrese, Pasquale

    2016-01-01

    Extensive behavioural, pharmacological, and neurological research reports stress effects on mammalian memory processes. While stress effects on memory quantity have been known for decades, the influence of stress on multiple memory systems and their distinct contributions to the learning process have only recently been described. In this paper, after summarizing the fundamental biological aspects of stress/emotional arousal and recapitulating functionally and anatomically distinct memory systems, we review recent animal and human studies exploring the effects of stress on multiple memory systems. Apart from discussing the interaction between distinct memory systems in stressful situations, we will also outline the fundamental role of the amygdala in mediating such stress effects. Additionally, based on the methods applied in the herein discussed studies, we will discuss how memory translates into behaviour.

  7. The gravitational-wave memory effect

    International Nuclear Information System (INIS)

    Favata, Marc

    2010-01-01

    The nonlinear memory effect is a slowly growing, non-oscillatory contribution to the gravitational-wave amplitude. It originates from gravitational waves that are sourced by the previously emitted waves. In an ideal gravitational-wave interferometer a gravitational wave with memory causes a permanent displacement of the test masses that persists after the wave has passed. Surprisingly, the nonlinear memory affects the signal amplitude starting at leading (Newtonian-quadrupole) order. Despite this fact, the nonlinear memory is not easily extracted from current numerical relativity simulations. After reviewing the linear and nonlinear memory I summarize some recent work, including (1) computations of the memory contribution to the inspiral waveform amplitude (thus completing the waveform to third post-Newtonian order); (2) the first calculations of the nonlinear memory that include all phases of binary black hole coalescence (inspiral, merger, ringdown); and (3) realistic estimates of the detectability of the memory with LISA.

  8. Memory and Its Effect on Adult Function

    Directory of Open Access Journals (Sweden)

    Shokouh Navvabi-Nejad

    2000-07-01

    Full Text Available Memory capabilities, including its mechanisms and memory approaches weaken as age increases. However, the studies reveal that the content of memory, i.e. the knowledge stored in it, usually increases. Memory system includes sensory memory within which environmental information are recorded. Short-term memory is related to storing data at awareness level, whereas long-term memory is associated with  storing knowledge and past experiences. Psychological and physiological factors such as mental and physical health, nutrition, using narcotic substances and alcohol, and also stimulation during life may affect all functions of the elderly such as their memory. Unfortunately, many researchers overlooked the effects of these variables on subjects.

  9. Efficient Multi-Valued Bounded Model Checking for LTL over Quasi-Boolean Algebras

    Science.gov (United States)

    Andrade, Jefferson O.; Kameyama, Yukiyoshi

    Multi-valued Model Checking extends classical, two-valued model checking to multi-valued logic such as Quasi-Boolean logic. The added expressivity is useful in dealing with such concepts as incompleteness and uncertainty in target systems, while it comes with the cost of time and space. Chechik and others proposed an efficient reduction from multi-valued model checking problems to two-valued ones, but to the authors' knowledge, no study was done for multi-valued bounded model checking. In this paper, we propose a novel, efficient algorithm for multi-valued bounded model checking. A notable feature of our algorithm is that it is not based on reduction of multi-values into two-values; instead, it generates a single formula which represents multi-valuedness by a suitable encoding, and asks a standard SAT solver to check its satisfiability. Our experimental results show a significant improvement in the number of variables and clauses and also in execution time compared with the reduction-based one.

  10. Stress Effects on Working Memory, Explicit Memory, and Implicit Memory for Neutral and Emotional Stimuli in Healthy Men

    OpenAIRE

    Luethi, Mathias; Meier, Beat; Sandi, Carmen

    2009-01-01

    Stress is a strong modulator of memory function. However, memory is not a unitary process and stress seems to exert different effects depending on the memory type under study. Here, we explored the impact of social stress on different aspects of human memory, including tests for explicit memory and working memory (for neutral materials), as well as implicit memory (perceptual priming, contextual priming and classical conditioning for emotional stimuli). A total of 35 young adult...

  11. Memory effects on stochastic resonance

    Science.gov (United States)

    Neiman, Alexander; Sung, Wokyung

    1996-02-01

    We study the phenomenon of stochastic resonance (SR) in a bistable system with internal colored noise. In this situation the system possesses time-dependent memory friction connected with noise via the fluctuation-dissipation theorem, so that in the absence of periodic driving the system approaches the thermodynamic equilibrium state. For this non-Markovian case we find that memory usually suppresses stochastic resonance. However, for a large memory time SR can be enhanced by the memory.

  12. Multi-valued logic circuits using hybrid circuit consisting of three gates single-electron transistors (TG-SETs) and MOSFETs.

    Science.gov (United States)

    Shin, SeungJun; Yu, YunSeop; Choi, JungBum

    2008-10-01

    New multi-valued logic (MVL) families using the hybrid circuits consisting of three gates single-electron transistors (TG-SETs) and a metal-oxide-semiconductor field-effect transistor (MOSFET) are proposed. The use of SETs offers periodic literal characteristics due to Coulomb oscillation of SET, which allows a realization of binary logic (BL) circuits as well as multi-valued logic (MVL) circuits. The basic operations of the proposed MVL families are successfully confirmed through SPICE circuit simulation based on the physical device model of a TG-SET. The proposed MVL circuits are found to be much faster, but much larger power consumption than a previously reported MVL, and they have a trade-off between speed and power consumption. As an example to apply the newly developed MVL families, a half-adder is introduced.

  13. Memory effects in nuclear fragmentation?

    International Nuclear Information System (INIS)

    Colonna, M.; Di Toro, M.; Guarnera, A.

    1994-01-01

    A general procedure to identify instability regions which lead to multifragmentation events is presented. The dominant mode at the instability point is determined from the knowledge of the mean properties (density and temperature) of the system at that point. For spinodal instabilities the dependence of fragment structures on the dynamical conditions is studied changing the beam energy and the considered equation of state. An important competition between two dynamical effects, expansion of the system and growth of fluctuations, is revealed. It is shown that in heavy-ion central collisions at medium energies memory effects of the configuration formed at the instability time could be observed in the final fragmentation pattern. Some hints towards a fully dynamical picture of fragmentation processes are finally suggested. ((orig.))

  14. Magnonic interferometric switch for multi-valued logic circuits

    Science.gov (United States)

    Balynsky, Michael; Kozhevnikov, Alexander; Khivintsev, Yuri; Bhowmick, Tonmoy; Gutierrez, David; Chiang, Howard; Dudko, Galina; Filimonov, Yuri; Liu, Guanxiong; Jiang, Chenglong; Balandin, Alexander A.; Lake, Roger; Khitun, Alexander

    2017-01-01

    We investigated a possible use of the magnonic interferometric switches in multi-valued logic circuits. The switch is a three-terminal device consisting of two spin channels where input, control, and output signals are spin waves. Signal modulation is achieved via the interference between the source and gate spin waves. We report experimental data on a micrometer scale prototype based on the Y3Fe2(FeO4)3 structure. The output characteristics are measured at different angles of the bias magnetic field. The On/Off ratio of the prototype exceeds 13 dB at room temperature. Experimental data are complemented by the theoretical analysis and the results of micro magnetic simulations showing spin wave propagation in a micrometer size magnetic junction. We also present the results of numerical modeling illustrating the operation of a nanometer-size switch consisting of just 20 spins in the source-drain channel. The utilization of spin wave interference as a switching mechanism makes it possible to build nanometer-scale logic gates, and minimize energy per operation, which is limited only by the noise margin. The utilization of phase in addition to amplitude for information encoding offers an innovative route towards multi-state logic circuits. We describe possible implementation of the three-value logic circuits based on the magnonic interferometric switches. The advantages and shortcomings inherent in interferometric switches are also discussed.

  15. Item Effects in Recognition Memory for Words

    Science.gov (United States)

    Freeman, Emily; Heathcote, Andrew; Chalmers, Kerry; Hockley, William

    2010-01-01

    We investigate the effects of word characteristics on episodic recognition memory using analyses that avoid Clark's (1973) "language-as-a-fixed-effect" fallacy. Our results demonstrate the importance of modeling word variability and show that episodic memory for words is strongly affected by item noise (Criss & Shiffrin, 2004), as measured by the…

  16. The Attentional Boost Effect and Context Memory

    Science.gov (United States)

    Mulligan, Neil W.; Smith, S. Adam; Spataro, Pietro

    2016-01-01

    Stimuli co-occurring with targets in a detection task are better remembered than stimuli co-occurring with distractors--the attentional boost effect (ABE). The ABE is of interest because it is an exception to the usual finding that divided attention during encoding impairs memory. The effect has been demonstrated in tests of item memory but it is…

  17. The attentional boost effect and context memory.

    Science.gov (United States)

    Mulligan, Neil W; Smith, S Adam; Spataro, Pietro

    2016-04-01

    Stimuli co-occurring with targets in a detection task are better remembered than stimuli co-occurring with distractors-the attentional boost effect (ABE). The ABE is of interest because it is an exception to the usual finding that divided attention during encoding impairs memory. The effect has been demonstrated in tests of item memory but it is unclear if context memory is likewise affected. Some accounts suggest enhanced perceptual encoding or associative binding, predicting an ABE on context memory, whereas other evidence suggests a more abstract, amodal basis of the effect. In Experiment 1, context memory was assessed in terms of an intramodal perceptual detail, the font and color of the study word. Experiment 2 examined context memory cross-modally, assessing memory for the modality (visual or auditory) of the study word. Experiments 3 and 4 assessed context memory with list discrimination, in which 2 study lists are presented and participants must later remember which list (if either) a test word came from. In all experiments, item (recognition) memory was also assessed and consistently displayed a robust ABE. In contrast, the attentional-boost manipulation did not enhance context memory, whether defined in terms of visual details, study modality, or list membership. There was some evidence that the mode of responding on the detection task (motoric response as opposed to covert counting of targets) may impact context memory but there was no evidence of an effect of target detection, per se. In sum, the ABE did not occur in context memory with verbal materials. (c) 2016 APA, all rights reserved).

  18. Effects of memory load on hemispheric asymmetries of colour memory.

    Science.gov (United States)

    Clapp, Wes; Kirk, Ian J; Hausmann, Markus

    2007-03-01

    Hemispheric asymmetries in colour perception have been a matter of debate for some time. Recent evidence suggests that lateralisation of colour processing may be largely task specific. Here we investigated hemispheric asymmetries during different types and phases of a delayed colour-matching (recognition) memory task. A total of 11 male and 12 female right-handed participants performed colour-memory tasks. The task involved presentation of a set of colour stimuli (encoding), and subsequent indication (forced choice) of which colours in a larger set had previously appeared at the retrieval or recognition phase. The effect of memory load (set size), and the effect of lateralisation at the encoding or retrieval phases were investigated. Overall, the results indicate a right hemisphere advantage in colour processing, which was particularly pronounced in high memory load conditions, and was seen in males rather than female participants. The results suggest that verbal (mnemonic) strategies can significantly affect the magnitude of hemispheric asymmetries in a non-verbal task.

  19. Memory effect and fast spinodal decomposition

    International Nuclear Information System (INIS)

    Koide, T.; Krein, G.; Ramos, Rudnei O.

    2007-01-01

    We consider the modification of the Cahn-Hilliard equation when a time delay process through a memory function is taken into account. We then study the process of spinodal decomposition in fast phase transitions associated with a conserved order parameter. The introduced memory effect plays an important role to obtain a finite group velocity. Then, we discuss the constraint for the parameters to satisfy causality. The memory effect is seen to affect the dynamics of phase transition at short times and have the effect of delaying, in a significant way, the process of rapid growth of the order parameter that follows a quench into the spinodal region. (author)

  20. Generalized multivalued equilibrium-like problems: auxiliary principle technique and predictor-corrector methods

    Directory of Open Access Journals (Sweden)

    Vahid Dadashi

    2016-02-01

    Full Text Available Abstract This paper is dedicated to the introduction a new class of equilibrium problems named generalized multivalued equilibrium-like problems which includes the classes of hemiequilibrium problems, equilibrium-like problems, equilibrium problems, hemivariational inequalities, and variational inequalities as special cases. By utilizing the auxiliary principle technique, some new predictor-corrector iterative algorithms for solving them are suggested and analyzed. The convergence analysis of the proposed iterative methods requires either partially relaxed monotonicity or jointly pseudomonotonicity of the bifunctions involved in generalized multivalued equilibrium-like problem. Results obtained in this paper include several new and known results as special cases.

  1. Noise-based logic: Binary, multi-valued, or fuzzy, with optional superposition of logic states

    Energy Technology Data Exchange (ETDEWEB)

    Kish, Laszlo B. [Texas A and M University, Department of Electrical and Computer Engineering, College Station, TX 77843-3128 (United States)], E-mail: laszlo.kish@ece.tamu.edu

    2009-03-02

    A new type of deterministic (non-probabilistic) computer logic system inspired by the stochasticity of brain signals is shown. The distinct values are represented by independent stochastic processes: independent voltage (or current) noises. The orthogonality of these processes provides a natural way to construct binary or multi-valued logic circuitry with arbitrary number N of logic values by using analog circuitry. Moreover, the logic values on a single wire can be made a (weighted) superposition of the N distinct logic values. Fuzzy logic is also naturally represented by a two-component superposition within the binary case (N=2). Error propagation and accumulation are suppressed. Other relevant advantages are reduced energy dissipation and leakage current problems, and robustness against circuit noise and background noises such as 1/f, Johnson, shot and crosstalk noise. Variability problems are also non-existent because the logic value is an AC signal. A similar logic system can be built with orthogonal sinusoidal signals (different frequency or orthogonal phase) however that has an extra 1/N type slowdown compared to the noise-based logic system with increasing number of N furthermore it is less robust against time delay effects than the noise-based counterpart.

  2. Noise-based logic: Binary, multi-valued, or fuzzy, with optional superposition of logic states

    International Nuclear Information System (INIS)

    Kish, Laszlo B.

    2009-01-01

    A new type of deterministic (non-probabilistic) computer logic system inspired by the stochasticity of brain signals is shown. The distinct values are represented by independent stochastic processes: independent voltage (or current) noises. The orthogonality of these processes provides a natural way to construct binary or multi-valued logic circuitry with arbitrary number N of logic values by using analog circuitry. Moreover, the logic values on a single wire can be made a (weighted) superposition of the N distinct logic values. Fuzzy logic is also naturally represented by a two-component superposition within the binary case (N=2). Error propagation and accumulation are suppressed. Other relevant advantages are reduced energy dissipation and leakage current problems, and robustness against circuit noise and background noises such as 1/f, Johnson, shot and crosstalk noise. Variability problems are also non-existent because the logic value is an AC signal. A similar logic system can be built with orthogonal sinusoidal signals (different frequency or orthogonal phase) however that has an extra 1/N type slowdown compared to the noise-based logic system with increasing number of N furthermore it is less robust against time delay effects than the noise-based counterpart

  3. Noise-based logic: Binary, multi-valued, or fuzzy, with optional superposition of logic states

    Science.gov (United States)

    Kish, Laszlo B.

    2009-03-01

    A new type of deterministic (non-probabilistic) computer logic system inspired by the stochasticity of brain signals is shown. The distinct values are represented by independent stochastic processes: independent voltage (or current) noises. The orthogonality of these processes provides a natural way to construct binary or multi-valued logic circuitry with arbitrary number N of logic values by using analog circuitry. Moreover, the logic values on a single wire can be made a (weighted) superposition of the N distinct logic values. Fuzzy logic is also naturally represented by a two-component superposition within the binary case ( N=2). Error propagation and accumulation are suppressed. Other relevant advantages are reduced energy dissipation and leakage current problems, and robustness against circuit noise and background noises such as 1/f, Johnson, shot and crosstalk noise. Variability problems are also non-existent because the logic value is an AC signal. A similar logic system can be built with orthogonal sinusoidal signals (different frequency or orthogonal phase) however that has an extra 1/N type slowdown compared to the noise-based logic system with increasing number of N furthermore it is less robust against time delay effects than the noise-based counterpart.

  4. Bumblebees exhibit the memory spacing effect

    Science.gov (United States)

    Toda, Nicholas R. T.; Song, Jeremy; Nieh, James C.

    2009-10-01

    Associative learning is key to how bees recognize and return to rewarding floral resources. It thus plays a major role in pollinator floral constancy and plant gene flow. Honeybees are the primary model for pollinator associative learning, but bumblebees play an important ecological role in a wider range of habitats, and their associative learning abilities are less well understood. We assayed learning with the proboscis extension reflex (PER), using a novel method for restraining bees (capsules) designed to improve bumblebee learning. We present the first results demonstrating that bumblebees exhibit the memory spacing effect. They improve their associative learning of odor and nectar reward by exhibiting increased memory acquisition, a component of long-term memory formation, when the time interval between rewarding trials is increased. Bombus impatiens forager memory acquisition (average discrimination index values) improved by 129% and 65% at inter-trial intervals (ITI) of 5 and 3 min, respectively, as compared to an ITI of 1 min. Memory acquisition rate also increased with increasing ITI. Encapsulation significantly increases olfactory memory acquisition. Ten times more foragers exhibited at least one PER response during training in capsules as compared to traditional PER harnesses. Thus, a novel conditioning assay, encapsulation, enabled us to improve bumblebee-learning acquisition and demonstrate that spaced learning results in better memory consolidation. Such spaced learning likely plays a role in forming long-term memories of rewarding floral resources.

  5. Is Working Memory Training Effective?

    Science.gov (United States)

    Shipstead, Zach; Redick, Thomas S.; Engle, Randall W.

    2012-01-01

    Working memory (WM) is a cognitive system that strongly relates to a person's ability to reason with novel information and direct attention to goal-relevant information. Due to the central role that WM plays in general cognition, it has become the focus of a rapidly growing training literature that seeks to affect broad cognitive change through…

  6. Acute Alcohol Effects on Repetition Priming and Word Recognition Memory with Equivalent Memory Cues

    Science.gov (United States)

    Ray, Suchismita; Bates, Marsha E.

    2006-01-01

    Acute alcohol intoxication effects on memory were examined using a recollection-based word recognition memory task and a repetition priming task of memory for the same information without explicit reference to the study context. Memory cues were equivalent across tasks; encoding was manipulated by varying the frequency of occurrence (FOC) of words…

  7. Existence and convergence theorems for a class of multi-valued variational inclusions in Banach spaces

    International Nuclear Information System (INIS)

    Chidume, C.E.; Zegeye, H.; Kazmi, K.R.

    2002-07-01

    An existence theorem for a new class of multi-valued variational inclusion problems is established in smooth Banach spaces. Further, it is shown that a sequence of a Mann-type iteration algorithm is strongly convergent to the solutions in this class of variational inclusion problems. (author)

  8. Eigenvalue for Densely Defined Perturbations of Multivalued Maximal Monotone Operators in Reflexive Banach Spaces

    Directory of Open Access Journals (Sweden)

    Boubakari Ibrahimou

    2013-01-01

    maximal monotone with and . Using the topological degree theory developed by Kartsatos and Quarcoo we study the eigenvalue problem where the operator is a single-valued of class . The existence of continuous branches of eigenvectors of infinite length then could be easily extended to the case where the operator is multivalued and is investigated.

  9. On the approximative normal values of multivalued operators in topological vector space

    International Nuclear Information System (INIS)

    Nguyen Minh Chuong; Khuat van Ninh

    1989-09-01

    In this paper the problem of approximation of normal values of multivalued linear closed operators from topological vector Mackey space into E-space is considered. Existence of normal value and convergence of approximative values to normal value are proved. (author). 4 refs

  10. Creating Büchi automata for multi-valued model checking

    NARCIS (Netherlands)

    Vijzelaar, Stefan J.J.; Fokkink, Wan J.

    2017-01-01

    In explicit state model checking of linear temporal logic properties, a Büchi automaton encodes a temporal property. It interleaves with a Kripke model to form a state space, which is searched for counterexamples. Multi-valued model checking considers additional truth values beyond the Boolean true

  11. Existence principles for inclusions of Hammerstein type involving noncompact acyclic multivalued maps

    Directory of Open Access Journals (Sweden)

    Jean-Francois Couchouron

    2002-01-01

    Full Text Available We apply Monch type fixed point theorems for acyclic multivalued maps to the solvability of inclusions of Hammerstein type in Banach spaces. Our approach makes possible to unify and improve the existence theories for nonlinear evolution problems and abstract integral inclusions of Volterra and Fredholm type.

  12. Quasilinear parabolic variational inequalities with multi-valued lower-order terms

    Science.gov (United States)

    Carl, Siegfried; Le, Vy K.

    2014-10-01

    In this paper, we provide an analytical frame work for the following multi-valued parabolic variational inequality in a cylindrical domain : Find and an such that where is some closed and convex subset, A is a time-dependent quasilinear elliptic operator, and the multi-valued function is assumed to be upper semicontinuous only, so that Clarke's generalized gradient is included as a special case. Thus, parabolic variational-hemivariational inequalities are special cases of the problem considered here. The extension of parabolic variational-hemivariational inequalities to the general class of multi-valued problems considered in this paper is not only of disciplinary interest, but is motivated by the need in applications. The main goals are as follows. First, we provide an existence theory for the above-stated problem under coercivity assumptions. Second, in the noncoercive case, we establish an appropriate sub-supersolution method that allows us to get existence, comparison, and enclosure results. Third, the order structure of the solution set enclosed by sub-supersolutions is revealed. In particular, it is shown that the solution set within the sector of sub-supersolutions is a directed set. As an application, a multi-valued parabolic obstacle problem is treated.

  13. Age effects on explicit and implicit memory

    Directory of Open Access Journals (Sweden)

    Emma eWard

    2013-09-01

    Full Text Available It is well documented that explicit memory (e.g., recognition declines with age. In contrast, many argue that implicit memory (e.g., priming is preserved in healthy aging. For example, priming on tasks such as perceptual identification is often not statistically different in groups of young and older adults. Such observations are commonly taken as evidence for distinct explicit and implicit learning/memory systems. In this article we discuss several lines of evidence that challenge this view. We describe how patterns of differential age-related decline may arise from differences in the ways in which the two forms of memory are commonly measured, and review recent research suggesting that under improved measurement methods, implicit memory is not age-invariant. Formal computational models are of considerable utility in revealing the nature of underlying systems. We report the results of applying single and multiple-systems models to data on age effects in implicit and explicit memory. Model comparison clearly favours the single-system view. Implications for the memory systems debate are discussed.

  14. Age effects on explicit and implicit memory.

    Science.gov (United States)

    Ward, Emma V; Berry, Christopher J; Shanks, David R

    2013-01-01

    It is well-documented that explicit memory (e.g., recognition) declines with age. In contrast, many argue that implicit memory (e.g., priming) is preserved in healthy aging. For example, priming on tasks such as perceptual identification is often not statistically different in groups of young and older adults. Such observations are commonly taken as evidence for distinct explicit and implicit learning/memory systems. In this article we discuss several lines of evidence that challenge this view. We describe how patterns of differential age-related decline may arise from differences in the ways in which the two forms of memory are commonly measured, and review recent research suggesting that under improved measurement methods, implicit memory is not age-invariant. Formal computational models are of considerable utility in revealing the nature of underlying systems. We report the results of applying single and multiple-systems models to data on age effects in implicit and explicit memory. Model comparison clearly favors the single-system view. Implications for the memory systems debate are discussed.

  15. Pitch memory and exposure effects.

    OpenAIRE

    Ben-Haim, Moshe Shay; Eitan, Zohar; Chajut, Eran

    2014-01-01

    Recent studies indicate that the ability to represent absolute pitch values in long-term memory (LTM), long believed to be the possession of a small minority of trained musicians endowed with "absolute pitch" (AP), is in fact shared to some extent by a considerable proportion of the population. The current study examined whether this newly-discovered ability affects aspects of music and auditory cognition, particularly pitch learning and evaluation. Our starting points are two well establishe...

  16. Pitch memory and exposure effects.

    Science.gov (United States)

    Ben-Haim, Moshe Shay; Eitan, Zohar; Chajut, Eran

    2014-02-01

    Recent studies indicate that the ability to represent absolute pitch values in long-term memory, long believed to be the possession of a small minority of trained musicians endowed with "absolute pitch," is in fact shared to some extent by a considerable proportion of the population. The current study examined whether this newly discovered ability affects aspects of music and auditory cognition, particularly pitch learning and evaluation. Our starting points are two well-established premises: (1) frequency of occurrence has an influence on the way we process stimuli; (2) in Western music, some pitches and musical keys are much more frequent than others. Based on these premises, we hypothesize that if absolute pitch values are indeed represented in long-term memory, pitch frequency of occurrence in music would significantly affect cognitive processes, in particular pitch learning and evaluation. Two experiments were designed to test this hypothesis in participants with no absolute pitch, most with little or no musical training. Experiment 1 demonstrated a faster response and a learning advantage for frequent pitches over infrequent pitches in an identification task. In Experiment 2, participants evaluated infrequent pitches as more pleasing than frequent pitches when presented in isolation. These results suggest that absolute pitch representation in memory may play a substantial, hitherto unacknowledged role in auditory (and specifically musical) cognition. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  17. The effect of empathy on eyewitness memory

    Directory of Open Access Journals (Sweden)

    2015-09-01

    Full Text Available Aims: Numerous factors have been identified that can influence eyewitness memory. These factors lead to an increased susceptibility to the misinformation effect, potentially resulting in critical errors in testimony. One other potential influencing factor may be empathy. Empathy is considered as the reactions of an individual to something another person is experiencing. Research has indicated empathy to be a multidimensional construct, combining cognitive and emotional concepts. Empathy has yet to be investigated as an influencing factor, therefore, the current research sought to examine the effect of empathy on eyewitness memory. Method: Participants (n = 60 completed an online survey consisting of a short video, followed by reading a short narrative containing correct and misinformation. One group of participants (N=31 also received an empathy induction. They then completed empathy measures, a cued recall memory test and a recognition memory test. The memory test contained questions relating to the correct and misinformation. Results: Overall there was no difference between groups on general empathy. The empathy induction group had more event related empathy, however, there was no effect of empathy on memory accuracy. For cued recall, participants were more accurate on questions relating to correct (89% information compared to misleading (37% information. For the recognition questions, participants were about as accurate for the correct (63% and misleading (60% information. Conclusions: These findings indicate that feelings of empathy toward the victim of a crime may not improve the accuracy of witness memory. Cued recall results in superior memory performance for correct information, but very poor performance for misleading information. Recognition recall is moderately accurate for both correct and misleading information.

  18. Effects of stereotypes and suggestion on memory.

    Science.gov (United States)

    Shechory, Mally; Nachson, Israel; Glicksohn, Joseph

    2010-02-01

    In this study, the interactive effect of stereotype and suggestion on accuracy of memory was examined by presenting 645 participants (native Israelis and immigrants from the former Soviet Union and Ethiopia) with three versions of a story about a worker who is waiting in a manager's office for a meeting. All versions were identical except for the worker's name, which implied a Russian or an Ethiopian immigrant or a person of no ethnic origin. Each participant was presented with one version of the story. After an hour delay, the participants' memories were tested via two questionnaires that differed in terms of level of suggestion. Data analyses show that (a) when a suggestion matched the participant's stereotypical perception, the suggestion was incorporated into memory but (b) when the suggestion contradicted the stereotype, it did not influence memory. The conclusion was that recall is influenced by stereotypes but can be enhanced by compatible suggestions.

  19. Testing Memories of Personally Experienced Events: The Testing Effect Seems Not to Persist in Autobiographical Memory

    Science.gov (United States)

    Emmerdinger, Kathrin J.; Kuhbandner, Christof

    2018-01-01

    Numerous studies have shown that retrieving contents from memory in a test improves long-term retention for those contents, even when compared to restudying (i.e., the “testing effect”). The beneficial effect of retrieval practice has been demonstrated for many different types of memory representations; however, one particularly important memory system has not been addressed in previous testing effect research: autobiographical memory. The aim of the present study was to examine the effect of retrieving memories for personally experienced events on long-term memory for those events. In an initial elicitation session, participants described memories for personally experienced events in response to a variety of cue words. In a retrieval practice/restudy session the following day, they repeatedly practiced retrieval for half of their memories by recalling and writing down the previously described events; the other half of memories was restudied by rereading and copying the event descriptions. Long-term retention of all previously collected memories was assessed at two different retention intervals (2 weeks and 13 weeks). In the retrieval practice session, a hypermnesic effect emerged, with memory performance increasing across the practice cycles. Long-term memory performance significantly dropped from the 2-weeks to the 13-weeks retention interval, but no significant difference in memory performance was observed between previously repeatedly retrieved and previously repeatedly restudied memories. Thus, in autobiographical memory, retrieval practice seems to be no more beneficial for long-term retention than repeated re-exposure. PMID:29881365

  20. Effects of glucocorticoids on memory retrieval and reconsolidation of recent and remote memories in mice

    Directory of Open Access Journals (Sweden)

    Mansoreh Najjar

    2013-06-01

    Full Text Available Introduction: Previous studies demonstrated that the systemic injection of corticosterone impairs both retrieval and reconsolidation of fear memory in experimental animals. Here, we investigated whether these disrupting effects of corticosterone depend on the age (recent or remote of the memory in mice. Materials and Methods: Mice were trained and tested in an inhibitory avoidance task (50 Hz, 1mA for 3 S. Corticosterone (1, 3 and 10mg/kg injected 30 min before of retrieval test of either a two-day recent or 36-day remote memory. Memory retrieval tested during 10 min. For memory reconsolidation experiments immediately after memory reactivation of two-day recent or 36-day remote memories, mice received corticosterone (1, 3 and 10mg/kg or vehicle. Two, five, seven and nine days after memory reactivation, mice were returned to the context for 10 min, and step-through latency was recorded.Results: For memory retrieval, corticosterone impaired subsequent expression of both recent and remote memories. Similar effect was found on the reconsolidation of both memories. Additionally, a higher dose of corticosterone was needed to impair retrieval and reconsolidation of remote memory. No significant differences were found on the amount of memory deficit induced by corticosterone among memories with different age. Conclusion: Our data indicate that the efficacy of corticosterone in impairing retrieval and reconsolidation of fear memory is not limited to the age of memory

  1. Working memory capacity and the spacing effect in cued recall.

    Science.gov (United States)

    Delaney, Peter F; Godbole, Namrata R; Holden, Latasha R; Chang, Yoojin

    2018-07-01

    Spacing repetitions typically improves memory (the spacing effect). In three cued recall experiments, we explored the relationship between working memory capacity and the spacing effect. People with higher working memory capacity are more accurate on memory tasks that require retrieval relative to people with lower working memory capacity. The experiments used different retention intervals and lags between repetitions, but were otherwise similar. Working memory capacity and spacing of repetitions both improved memory in most of conditions, but they did not interact, suggesting additive effects. The results are consistent with the ACT-R model's predictions, and with a study-phase recognition process underpinning the spacing effect in cued recall.

  2. The memory effect for plane gravitational waves

    Science.gov (United States)

    Zhang, P.-M.; Duval, C.; Gibbons, G. W.; Horvathy, P. A.

    2017-09-01

    We give an account of the gravitational memory effect in the presence of the exact plane wave solution of Einstein's vacuum equations. This allows an elementary but exact description of the soft gravitons and how their presence may be detected by observing the motion of freely falling particles. The theorem of Bondi and Pirani on caustics (for which we present a new proof) implies that the asymptotic relative velocity is constant but not zero, in contradiction with the permanent displacement claimed by Zel'dovich and Polnarev. A non-vanishing asymptotic relative velocity might be used to detect gravitational waves through the "velocity memory effect", considered by Braginsky, Thorne, Grishchuk, and Polnarev.

  3. Regularity effect in prospective memory during aging

    OpenAIRE

    Blondelle, Geoffrey; Hainselin, Mathieu; Gounden, Yannick; Heurley, Laurent; Voisin, Hélène; Megalakaki, Olga; Bressous, Estelle; Quaglino, Véronique

    2016-01-01

    Background: Regularity effect can affect performance in prospective memory (PM), but little is known on the cognitive processes linked to this effect. Moreover, its impacts with regard to aging remain unknown. To our knowledge, this study is the first to examine regularity effect in PM in a lifespan perspective, with a sample of young, intermediate, and older adults.Objective and design: Our study examined the regularity effect in PM in three groups of participants: 28 young adults (18–30), 1...

  4. Are our memory predictions absolute or relative? : The effect of comparison on memory judgments

    OpenAIRE

    Karademir, Derya

    2016-01-01

    Cataloged from PDF version of article. Thesis (M.S.): Bilkent University, Department of Psychology, İhsan Doğramacı Bilkent University, 2016. Includes bibliographical references (leaves 57-64). The effect of divided attention on memory is well documented. However, its effects on memory predictions are not known. One of the aims of the present study was to investigate whether divided attention affects memory performance and prospective memory predictions. The other aim of the current ...

  5. Regularity effect in prospective memory during aging

    Directory of Open Access Journals (Sweden)

    Geoffrey Blondelle

    2016-10-01

    Full Text Available Background: Regularity effect can affect performance in prospective memory (PM, but little is known on the cognitive processes linked to this effect. Moreover, its impacts with regard to aging remain unknown. To our knowledge, this study is the first to examine regularity effect in PM in a lifespan perspective, with a sample of young, intermediate, and older adults. Objective and design: Our study examined the regularity effect in PM in three groups of participants: 28 young adults (18–30, 16 intermediate adults (40–55, and 25 older adults (65–80. The task, adapted from the Virtual Week, was designed to manipulate the regularity of the various activities of daily life that were to be recalled (regular repeated activities vs. irregular non-repeated activities. We examine the role of several cognitive functions including certain dimensions of executive functions (planning, inhibition, shifting, and binding, short-term memory, and retrospective episodic memory to identify those involved in PM, according to regularity and age. Results: A mixed-design ANOVA showed a main effect of task regularity and an interaction between age and regularity: an age-related difference in PM performances was found for irregular activities (older < young, but not for regular activities. All participants recalled more regular activities than irregular ones with no age effect. It appeared that recalling of regular activities only involved planning for both intermediate and older adults, while recalling of irregular ones were linked to planning, inhibition, short-term memory, binding, and retrospective episodic memory. Conclusion: Taken together, our data suggest that planning capacities seem to play a major role in remembering to perform intended actions with advancing age. Furthermore, the age-PM-paradox may be attenuated when the experimental design is adapted by implementing a familiar context through the use of activities of daily living. The clinical

  6. Caffeine effects on mood and memory.

    Science.gov (United States)

    Herz, R S

    1999-09-01

    The purpose of the present research was to assess whether a psychoactive dose of caffeine would have differential affects on the mood dimensions of arousal versus feelings of pleasantness and whether these mood alterations would influence memory either by (1) the experience of arousal at learning and/or (2) altered and congruent mood states at learning and recall. To address these questions, the administration of 5 mg/kg caffeine or placebo at learning and retrieval sessions was manipulated and subjects' mood was evaluated by several different self-report measures. Sixteen words were incidentally studied during the learning session and memory was evaluated by the number of words correctly recalled at the retrieval session two days later. Results revealed that caffeine reliably increased arousal, but did not affect any emotion dimensions related to feelings of pleasure. Subjects who received caffeine at learning and retrieval were also in equivalent mood states at both sessions. Moreover, caffeine did not produce any effects on memory; thus, neither hypothesis concerning the influence of arousal on memory was supported. These data show that caffeine is a useful method for manipulating arousal in the laboratory without influencing feelings of pleasantness or learning and memory performance.

  7. Time course of effects of emotion on item memory and source memory for Chinese words.

    Science.gov (United States)

    Wang, Bo; Fu, Xiaolan

    2011-05-01

    Although many studies have investigated the effect of emotion on memory, it is unclear whether the effect of emotion extends to all aspects of an event. In addition, it is poorly understood how effects of emotion on item memory and source memory change over time. This study examined the time course of effects of emotion on item memory and source memory. Participants learned intentionally a list of neutral, positive, and negative Chinese words, which were presented twice, and then took test of free recall, followed by recognition and source memory tests, at one of eight delayed points of time. The main findings are (within the time frame of 2 weeks): (1) Negative emotion enhances free recall, whereas there is only a trend that positive emotion enhances free recall. In addition, negative and positive emotions have different points of time at which their effects on free recall reach the greatest magnitude. (2) Negative emotion reduces recognition, whereas positive emotion has no effect on recognition. (3) Neither positive nor negative emotion has any effect on source memory. The above findings indicate that effect of emotion does not necessarily extend to all aspects of an event and that valence is a critical modulating factor in effect of emotion on item memory. Furthermore, emotion does not affect the time course of item memory and source memory, at least with a time frame of 2 weeks. This study has implications for establishing the theoretical model regarding the effect of emotion on memory. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Enhancing the production effect in memory.

    Science.gov (United States)

    Quinlan, Chelsea K; Taylor, Tracy L

    2013-01-01

    The production effect is the finding that subsequent memory is better for words that are produced than for words that are not produced. Whereas the current literature demonstrates that reading aloud is the most effective form of production, the distinctiveness account used to explain the production effect predicts that there is nothing special about reading aloud per se: Other forms of vocal production that include an additional distinct element should produce even greater subsequent memory benefits than reading aloud. To test this, we presented participants with study words that they were instructed to read aloud loudly, read aloud, or read silently (Experiment 1); sing, read aloud, or read silently (Experiment 2); and sing, read aloud loudly, read aloud, or read silently (Experiment 3). We observed that both reading items aloud loudly (Experiments 1 and 3) and singing items (Experiments 2 and 3) at study resulted in greater subsequent recognition than reading items aloud in a normal voice; singing had a larger memory benefit than reading aloud loudly (Experiment 3). Our findings support the distinctiveness hypothesis by demonstrating that there are other forms of production, such as singing and reading aloud loudly that have a more pronounced effect on memory than reading aloud.

  9. Memory effects in syntactic ERP tasks

    NARCIS (Netherlands)

    Sabourin, L.L.; Stowe, L.A.

    The study presented here investigated the role of memory in normal sentence processing by looking at ERP effects to normal sentences and sentences containing grammatical violations. Sentences where the critical word was in the middle of the sentence were compared to sentences where the critical word

  10. Topological fixed point theory for singlevalued and multivalued mappings and applications

    CERN Document Server

    Ben Amar, Afif

    2016-01-01

    This is a monograph covering topological fixed point theory for several classes of single and multivalued maps. The authors begin by presenting basic notions in locally convex topological vector spaces. Special attention is then devoted to weak compactness, in particular to the theorems of Eberlein–Šmulian, Grothendick and Dunford–Pettis. Leray–Schauder alternatives and eigenvalue problems for decomposable single-valued nonlinear weakly compact operators in Dunford–Pettis spaces are considered, in addition to some variants of Schauder, Krasnoselskii, Sadovskii, and Leray–Schauder type fixed point theorems for different classes of weakly sequentially continuous operators on general Banach spaces. The authors then proceed with an examination of Sadovskii, Furi–Pera, and Krasnoselskii fixed point theorems and nonlinear Leray–Schauder alternatives in the framework of weak topologies and involving multivalued mappings with weakly sequentially closed graph. These results are formulated in terms of ax...

  11. Thermoinduced plastic flow and shape memory effects

    Directory of Open Access Journals (Sweden)

    Xiao Heng

    2011-01-01

    Full Text Available We propose an enhanced form of thermocoupled J2-flow models of finite deformation elastoplasticity with temperature-dependent yielding and hardening behaviour. The thermomechanical constitutive structure of these models is rendered free and explicit in the rigorous sense of thermodynamic consistency. Namely, with a free energy function explicitly introduced in terms of almost any given form of the thermomechanical constitutive functions, the requirements from the second law are identically fulfilled with positive internal dissipation. We study the case when a dependence of yielding and hardening on temperature is given and demonstrate that thermosensitive yielding with anisotropic hardening may give rise to appreciable plastic flow either in a process of heating or in a cyclic process of heating/cooling, thus leading to the findings of one- and two-way thermoinduced plastic flow. We then show that such theoretical findings turn out to be the effects found in shape memory materials, such as one- and two-way memory effects. Thus, shape memory effects may be explained to be thermoinduced plastic flow resulting from thermosensitive yielding and hardening behaviour. These and other relevant facts may suggest that, from a phenomenological standpoint, thermocoupled elastoplastic J2-flow models with thermosensitive yielding and hardening may furnish natural, straightforward descriptions of thermomechanical behaviour of shape memory materials.

  12. CONTEXT-CAPTURE MULTI-VALUED DECISION FUSION WITH FAULT TOLERANT CAPABILITY FOR WIRELESS SENSOR NETWORKS

    OpenAIRE

    Jun Wu; Shigeru Shimamoto

    2011-01-01

    Wireless sensor networks (WSNs) are usually utilized to perform decision fusion of event detection. Current decision fusion schemes are based on binary valued decision and do not consider bursty contextcapture. However, bursty context and multi-valued data are important characteristics of WSNs. One on hand, the local decisions from sensors usually have bursty and contextual characteristics. Fusion center must capture the bursty context information from the sensors. On the other hand, in pract...

  13. Claudio Moraga a passion for multi-valued logic and soft computing

    CERN Document Server

    Allende-Cid, Héctor

    2017-01-01

    The book is an authoritative collection of contributions by leading experts on the topics of fuzzy logic, multi-valued logic and neural network. Originally written as an homage to Claudio Moraga, seen by his colleagues as an example of concentration, discipline and passion for science, the book also represents a timely reference guide for advance students and researchers in the field of soft computing, and multiple-valued logic. .

  14. Common Fixed Point of Multivalued Generalized φ-Weak Contractive Mappings

    Directory of Open Access Journals (Sweden)

    Behzad Djafari Rouhani

    2010-01-01

    Full Text Available Fixed point and coincidence results are presented for multivalued generalized φ-weak contractive mappings on complete metric spaces, where φ:[0,+∞→[0,+∞ is a lower semicontinuous function with φ(0=0 and φ(t>0 for all t>0. Our results extend previous results by Zhang and Song (2009, as well as by Rhoades (2001, Nadler (1969, and Daffer and Kaneko (1995.

  15. Dissociation between Features and Feature Relations in Infant Memory: Effects of Memory Load.

    Science.gov (United States)

    Bhatt, Ramesh S.; Rovee-Collier, Carolyn

    1997-01-01

    Four experiments examined effects of the number of features and feature relations on learning and long-term memory in 3-month olds. Findings suggested that memory load size selectively constrained infants' long-term memory for relational information, suggesting that in infants, features and relations are psychologically distinct and that memory…

  16. Age differences in perceptions of memory strategy effectiveness for recent and remote memory.

    Science.gov (United States)

    Lineweaver, Tara T; Horhota, Michelle; Crumley, Jessica; Geanon, Catherine T; Juett, Jacqueline J

    2018-03-01

    We examined whether young and older adults hold different beliefs about the effectiveness of memory strategies for specific types of memory tasks and whether memory strategies are perceived to be differentially effective for young, middle-aged, and older targets. Participants rated the effectiveness of five memory strategies for 10 memory tasks at three target ages (20, 50, and 80 years old). Older adults did not strongly differentiate strategy effectiveness, viewing most strategies as similarly effective across memory tasks. Young adults held strategy-specific beliefs, endorsing external aids and physical health as more effective than a positive attitude or internal strategies, without substantial differentiation based on task. We also found differences in anticipated strategy effectiveness for targets of different ages. Older adults described cognitive and physical health strategies as more effective for older than middle-aged targets, whereas young adults expected these strategies to be equally effective for middle-aged and older target adults.

  17. Phosphorene/rhenium disulfide heterojunction-based negative differential resistance device for multi-valued logic

    Science.gov (United States)

    Shim, Jaewoo; Oh, Seyong; Kang, Dong-Ho; Jo, Seo-Hyeon; Ali, Muhammad Hasnain; Choi, Woo-Young; Heo, Keun; Jeon, Jaeho; Lee, Sungjoo; Kim, Minwoo; Song, Young Jae; Park, Jin-Hong

    2016-11-01

    Recently, negative differential resistance devices have attracted considerable attention due to their folded current-voltage characteristic, which presents multiple threshold voltage values. Because of this remarkable property, studies associated with the negative differential resistance devices have been explored for realizing multi-valued logic applications. Here we demonstrate a negative differential resistance device based on a phosphorene/rhenium disulfide (BP/ReS2) heterojunction that is formed by type-III broken-gap band alignment, showing high peak-to-valley current ratio values of 4.2 and 6.9 at room temperature and 180 K, respectively. Also, the carrier transport mechanism of the BP/ReS2 negative differential resistance device is investigated in detail by analysing the tunnelling and diffusion currents at various temperatures with the proposed analytic negative differential resistance device model. Finally, we demonstrate a ternary inverter as a multi-valued logic application. This study of a two-dimensional material heterojunction is a step forward toward future multi-valued logic device research.

  18. Phosphorene/rhenium disulfide heterojunction-based negative differential resistance device for multi-valued logic

    Science.gov (United States)

    Shim, Jaewoo; Oh, Seyong; Kang, Dong-Ho; Jo, Seo-Hyeon; Ali, Muhammad Hasnain; Choi, Woo-Young; Heo, Keun; Jeon, Jaeho; Lee, Sungjoo; Kim, Minwoo; Song, Young Jae; Park, Jin-Hong

    2016-01-01

    Recently, negative differential resistance devices have attracted considerable attention due to their folded current–voltage characteristic, which presents multiple threshold voltage values. Because of this remarkable property, studies associated with the negative differential resistance devices have been explored for realizing multi-valued logic applications. Here we demonstrate a negative differential resistance device based on a phosphorene/rhenium disulfide (BP/ReS2) heterojunction that is formed by type-III broken-gap band alignment, showing high peak-to-valley current ratio values of 4.2 and 6.9 at room temperature and 180 K, respectively. Also, the carrier transport mechanism of the BP/ReS2 negative differential resistance device is investigated in detail by analysing the tunnelling and diffusion currents at various temperatures with the proposed analytic negative differential resistance device model. Finally, we demonstrate a ternary inverter as a multi-valued logic application. This study of a two-dimensional material heterojunction is a step forward toward future multi-valued logic device research. PMID:27819264

  19. Effects of chewing in working memory processing.

    Science.gov (United States)

    Hirano, Yoshiyuki; Obata, Takayuki; Kashikura, Kenichi; Nonaka, Hiroi; Tachibana, Atsumichi; Ikehira, Hiroo; Onozuka, Minoru

    2008-05-09

    It has been generally suggested that chewing produces an enhancing effect on cognitive performance-related aspects of memory by the test battery. Furthermore, recent studies have shown that chewing is associated with activation of various brain regions, including the prefrontal cortex. However, little is known about the relation between cognitive performances affected by chewing and the neuronal activity in specified regions in the brain. We therefore examined the effects of chewing on neuronal activities in the brain during a working memory task using fMRI. The subjects chewed gum, without odor and taste components, between continuously performed two- or three-back (n-back) working memory tasks. Chewing increased the BOLD signals in the middle frontal gyrus (Brodmann's areas 9 and 46) in the dorsolateral prefrontal cortex during the n-back tasks. Furthermore, there were more prominent activations in the right premotor cortex, precuneus, thalamus, hippocampus and inferior parietal lobe during the n-back tasks after the chewing trial. These results suggest that chewing may accelerate or recover the process of working memory besides inducing improvement in the arousal level by the chewing motion.

  20. An Easy Way to Show Memory Color Effects.

    Science.gov (United States)

    Witzel, Christoph

    2016-01-01

    This study proposes and evaluates a simple stimulus display that allows one to measure memory color effects (the effect of object knowledge and memory on color perception). The proposed approach is fast and easy and does not require running an extensive experiment. It shows that memory color effects are robust to minor variations due to a lack of color calibration.

  1. An Easy Way to Show Memory Color Effects

    OpenAIRE

    Witzel, Christoph

    2016-01-01

    This study proposes and evaluates a simple stimulus display that allows one to measure memory color effects (the effect of object knowledge and memory on color perception). The proposed approach is fast and easy and does not require running an extensive experiment. It shows that memory color effects are robust to minor variations due to a lack of color calibration.

  2. Testing the exclusivity effect in location memory.

    Science.gov (United States)

    Clark, Daniel P A; Dunn, Andrew K; Baguley, Thom

    2013-01-01

    There is growing literature exploring the possibility of parallel retrieval of location memories, although this literature focuses primarily on the speed of retrieval with little attention to the accuracy of location memory recall. Baguley, Lansdale, Lines, and Parkin (2006) found that when a person has two or more memories for an object's location, their recall accuracy suggests that only one representation can be retrieved at a time (exclusivity). This finding is counterintuitive given evidence of non-exclusive recall in the wider memory literature. The current experiment explored the exclusivity effect further and aimed to promote an alternative outcome (i.e., independence or superadditivity) by encouraging the participants to combine multiple representations of space at encoding or retrieval. This was encouraged by using anchor (points of reference) labels that could be combined to form a single strongly associated combination. It was hypothesised that the ability to combine the anchor labels would allow the two representations to be retrieved concurrently, generating higher levels of recall accuracy. The results demonstrate further support for the exclusivity hypothesis, showing no significant improvement in recall accuracy when there are multiple representations of a target object's location as compared to a single representation.

  3. The investigation of Fe-Mn-based alloys with shape memory effect by small-angle scattering of polarized neutrons

    International Nuclear Information System (INIS)

    Kopitsa, G.P.; Runov, V.V.; Grigoriev, S.V.; Bliznuk, V.V.; Gavriljuk, V.G.; Glavatska, N.I.

    2003-01-01

    The small-angle polarized neutron scattering (SAPNS) technique has been used to study a nuclear and magnetic homogeneity in the distribution of both substituent (Si, Cr, Ni) and interstitial (C, N) alloying elements on the mesoscopic range in Fe-Mn-based alloys with shape memory effect (SME). The four groups of alloys with various basic compositions: FeMn 18 (wt%), FeMn 20 Si 6 , FeMn 20 Cr 9 N 0.2 and FeMn 17 Cr 9 Ni 4 Si 6 were investigated. It was found that the small-angle scattering of neutrons and depolarization on these alloys are very small altogether. The scattering did not exceed 1.5% from the incident beam and depolarization ∼2% for all samples. It means that these alloys are well nuclear and magnetically homogeneous on the scale of 10-1000 A. However, the difference in the homogeneity depending on the compositions still takes place. Thus, the adding of Si in FeMn 18 and FeMn 20 Cr 9 N 0.2 alloys improves the homogeneity pronouncedly. At once, the effect of the doping by C or N atoms on the homogeneity in FeMn 20 Si 6 and FeMn 17 Cr 9 Ni 4 Si 6 alloys is multivalued and depend on the presence of substitutional atoms (Ni and Cr). The capability of SAPNS as a method for the study of mesoscopic homogeneity in materials with SME and testing of the quality of their preparation is discussed

  4. Memory effect in uniformly heated granular gases

    Science.gov (United States)

    Trizac, E.; Prados, A.

    2014-07-01

    We evidence a Kovacs-like memory effect in a uniformly driven granular gas. A system of inelastic hard particles, in the low density limit, can reach a nonequilibrium steady state when properly forced. By following a certain protocol for the drive time dependence, we prepare the gas in a state where the granular temperature coincides with its long time value. The temperature subsequently does not remain constant but exhibits a nonmonotonic evolution with either a maximum or a minimum, depending on the dissipation and on the protocol. We present a theoretical analysis of this memory effect at Boltzmann-Fokker-Planck equation level and show that when dissipation exceeds a threshold, the response can be called anomalous. We find excellent agreement between the analytical predictions and direct Monte Carlo simulations.

  5. Memory effect for particle scattering in odd spacetime dimensions

    Science.gov (United States)

    Satishchandran, Gautam; Wald, Robert M.

    2018-01-01

    We investigate the gravitational memory effect for linearized perturbations off of Minkowski space in odd spacetime dimensions d by examining the effects of gravitational radiation from classical point particle scattering. We also investigate analogous memory effects for electromagnetic and scalar radiation. We find that there is no gravitational memory effect in all odd dimensions. For scalar and electromagnetic fields, there is no memory effect for d ≥7 ; for d =3 there is an infinite momentum memory effect, whereas for d =5 there is no momentum memory effect but the displacement of a test particle will grow unboundedly with time. Our results are further elucidated by analyzing the memory effect for any slowly moving source of compact spatial support in odd dimensions.

  6. Velocity Memory Effect for polarized gravitational waves

    Science.gov (United States)

    Zhang, P.-M.; Duval, C.; Gibbons, G. W.; Horvathy, P. A.

    2018-05-01

    Circularly polarized gravitational sandwich waves exhibit, as do their linearly polarized counterparts, the Velocity Memory Effect: freely falling test particles in the flat after-zone fly apart along straight lines with constant velocity. In the inside zone their trajectories combine oscillatory and rotational motions in a complicated way. For circularly polarized periodic gravitational waves some trajectories remain bounded, while others spiral outward. These waves admit an additional "screw" isometry beyond the usual five. The consequences of this extra symmetry are explored.

  7. Experimental Effects of Acute Exercise on Prospective Memory and False Memory.

    Science.gov (United States)

    Green, David; Loprinzi, Paul D

    2018-01-01

    Research demonstrates that acute exercise can enhance retrospective episodic memory performance. However, limited research has examined the effects of acute exercise on prospective memory, and no studies have examined the effects of exercise on false memory performance. This study examined the potential effects of acute exercise on prospective memory and false memory performance. A between-group randomized controlled trial was employed, with participants (college students; M age  = 20 years) randomized into an exercise group (15-minute acute bout of treadmill walking; N = 25) or a control group (15 minutes of sitting; N = 26). Prospective memory was assessed from two laboratory and two naturalistic assessments outside the lab. False memory was assessed using a word-list trial. There were no statistically significant differences in prospective memory based on group allocation (F Group×Time  = 1.17; P = 0.32; η 2  = 0.06). However, the control group recalled more false words and had a higher rate of false memory recognition (F Group×Time  = 3.15; P = 0.01; η 2  = 0.26). These findings indicate that acute moderate-intensity aerobic exercise is not associated with prospective memory performance but provides some suggestive evidence that acute exercise may reduce the rate of false memories.

  8. Time-dependent effects of cardiovascular exercise on memory

    DEFF Research Database (Denmark)

    Roig, Marc; Thomas, Richard; Mang, Cameron S

    2016-01-01

    We present new evidence supporting the hypothesis that the effects of cardiovascular exercise on memory can be regulated in a time-dependent manner. When the exercise stimulus is temporally coupled with specific phases of the memory formation process, a single bout of cardiovascular exercise may...... be sufficient to improve memory. SUMMARY: The timing of exercise in relation to the information to be remembered is critical to maximize the effects of acute cardiovascular exercise on memory....

  9. Study of memory effects in polymer dispersed liquid crystal films

    International Nuclear Information System (INIS)

    Han, Jinwoo

    2006-01-01

    In this work, we have studied the memory effects in polymer dispersed liquid crystal films. We found that optical responses, such as the memory effects, of the films depended strongly on the morphology. For example, memory effects were observed for films with polymer ball morphologies; however, only weak hysteresis effects were observed for films with droplet morphologies. In particular, a stronger memory effect was observed for films with more complicated polymer ball structures. Coincidentally, T TE , the temperature at which the memory state is thermally erased, was generally higher for the films exhibiting a stronger memory effect. In addition, studies of the temporal evolution of the films show that the memory effects become stronger after films have been kept on the shelf for a period of time. This change is likely to be associated with a modification of surface anchoring properties at the LC-polymer interface.

  10. Gender differences in episodic memory and visual working memory including the effects of age.

    Science.gov (United States)

    Pauls, Franz; Petermann, Franz; Lepach, Anja Christina

    2013-01-01

    Analysing the relationship between gender and memory, and examining the effects of age on the overall memory-related functioning, are the ongoing goals of psychological research. The present study examined gender and age group differences in episodic memory with respect to the type of task. In addition, these subgroup differences were also analysed in visual working memory. A sample of 366 women and 330 men, aged between 16 and 69 years of age, participated in the current study. Results indicate that women outperformed men on auditory memory tasks, whereas male adolescents and older male adults showed higher level performances on visual episodic and visual working memory measures. However, the size of gender-linked effects varied somewhat across age groups. Furthermore, results partly support a declining performance on episodic memory and visual working memory measures with increasing age. Although age-related losses in episodic memory could not be explained by a decreasing verbal and visuospatial ability with age, women's advantage in auditory episodic memory could be explained by their advantage in verbal ability. Men's higher level visual episodic memory performance was found to result from their advantage in visuospatial ability. Finally, possible methodological, biological, and cognitive explanations for the current findings are discussed.

  11. Effects of thought suppression on episodic memory.

    Science.gov (United States)

    Rassin, E; Merckelbach, H; Muris, P

    1997-11-01

    Subjects were shown a short film fragment. Following this, one group of subjects (n = 26) was instructed to suppress their thoughts about the film, while the other group (n = 24) received no instructions. After 5 hrs subjects returned to the laboratory and completed a questionnaire testing their memory about the film. Results showed that suppression subjects reported a higher frequency of thoughts about the film than control subjects. No evidence was obtained for Wegner, Quillian, and Houston's (1996; Journal of Personality and Social Psychology, 71, 680-691) claim that suppression has an undermining effect on memory for chronology. Possible causes for the differences between the results as obtained by Wegner et al., and those found in the present study are discussed. These causes may pertain to the experimental design, but also to differences in emotional impact of the stimulus material that was used in both studies.

  12. Joint effects of emotion and color on memory.

    Science.gov (United States)

    Kuhbandner, Christof; Pekrun, Reinhard

    2013-06-01

    Numerous studies have shown that memory is enhanced for emotionally negative and positive information relative to neutral information. We examined whether emotion-induced memory enhancement is influenced by low-level perceptual attributes such as color. Because in everyday life red is often used as a warning signal, whereas green signals security, we hypothesized that red might enhance memory for negative information and green memory for positive information. To capture the signaling function of colors, we measured memory for words standing out from the context by color, and manipulated the color and emotional significance of the outstanding words. Making words outstanding by color strongly enhanced memory, replicating the well-known von Restorff effect. Furthermore, memory for colored words was further increased by emotional significance, replicating the memory-enhancing effect of emotion. Most intriguingly, the effects of emotion on memory additionally depended on color type. Red strongly increased memory for negative words, whereas green strongly increased memory for positive words. These findings provide the first evidence that emotion-induced memory enhancement is influenced by color and demonstrate that different colors can have different functions in human memory.

  13. On the alleged memory-undermining effects of daydreaming.

    Science.gov (United States)

    Otgaar, Henry; Cleere, Colleen; Merckelbach, Harald; Peters, Maarten; Jelicic, Marko; Lynn, Steven Jay

    2016-01-01

    In three experiments, we examined the memory-undermining effects of daydreaming for (un)related stimuli. In Experiments 1 and 2, we tested whether daydreaming fosters forgetting of semantically interrelated material and hence, catalyzes false memory production. In Experiment 3, we examined the memory effects of different daydreaming instructions. In Experiment 1, daydreaming did not undermine correct recall of semantically interrelated words, nor did it affect false memories. In Experiment 2, we again failed to find that daydreaming exerted memory-undermining effects a. In Experiment 3, no memory effects were obtained using different daydreaming instructions. Together, our studies fail to show appreciable memory-undermining effects of daydreaming. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Differential Age Effects on Spatial and Visual Working Memory

    Science.gov (United States)

    Oosterman, Joukje M.; Morel, Sascha; Meijer, Lisette; Buvens, Cleo; Kessels, Roy P. C.; Postma, Albert

    2011-01-01

    The present study was intended to compare age effects on visual and spatial working memory by using two versions of the same task that differed only in presentation mode. The working memory task contained both a simultaneous and a sequential presentation mode condition, reflecting, respectively, visual and spatial working memory processes. Young…

  15. Effects of Acute Exercise on Long-Term Memory

    Science.gov (United States)

    Labban, Jeffrey D.; Etnier, Jennifer L.

    2011-01-01

    In this study, we tested the effect of acute exercise on long-term memory, specifically the timing of exercise relative to the memory challenge. We assessed memory via paragraph recall, in which participants listened to two paragraphs (exposure) and recounted them following a 35-min delay. Participants (n = 48) were randomly assigned to one of…

  16. Two component memory of Rotstein effect in nuclear emulsions

    International Nuclear Information System (INIS)

    Gushchin, E.M.; Lebedev, A.N.; Somov, S.V.; Timofeev, M.K.; Tipografshchik, G.I.

    1991-01-01

    Two sharply differing memory components - fast and slow -are simultaneously detected during investigation into the controlled mode of fast charged particle detection in simple nuclear emulsions, with the emulsion trace sensitivity, corresponding to these components, being about 5 time different. The value of memory time is T m ≅40 μs for fast memory and T m ≅3.5 ms for the slow one. The detection of two Rotstein effect memory components confirms the correctness of the trap model

  17. Calculation of the number of branches of multi-valued decision trees in computer aided importance rank of parameters

    Directory of Open Access Journals (Sweden)

    Tiszbierek Agnieszka

    2017-01-01

    Full Text Available An elaborated digital computer programme supporting the time-consuming process of selecting the importance rank of construction and operation parameters by means of stating optimum sets is based on the Quine – McCluskey algorithm of minimizing individual partial multi-valued logic functions. The example with real time data, calculated by means of the programme, showed that among the obtained optimum sets there were such which had a different number of real branches after being presented on the multi-valued logic decision tree. That is why an idea of elaborating another functionality of the programme – a module calculating the number of branches of real, multi-valued logic decision trees presenting optimum sets chosen by the programme was pursued. This paper presents the idea and the method for developing a module calculating the number of branches, real for each of optimum sets indicated by the programme, as well as to the calculation process.

  18. Studies on the memory effect in polyethylene

    International Nuclear Information System (INIS)

    Lopez, M.A.; Burillo, G.; Charlesby, A.

    1994-01-01

    Polyethylene films of LDPE, a commercial product of PEMEX Mexico, with three different thicknesses were stretched from 1 cm to various lengths, and irradiated in air and in vacuum, at doses from 0 to 730 kGy. The effect of stretching on the ''memory effect'', % of gel formed, crystallinity, radio-chemical yield of crosslinking G c and scission G d was determined. Maximum shrinking effect is obtained at temperatures above the crystalline melting point, and is almost the same at any irradiation dose, from 0 to 525 kGy; in the case of doses from 713 kGy up, the recovery decreases slightly due to higher density of crosslinking. The increase of draw ratio from 5 to 6.5 has no significant effect on recovery. Preirradiation of 40 kGy in air before stretching has no significant effect on recovery but minimizes possible creep during the stretching and irradiation process. (author)

  19. Periodic and almost periodic solutions for multi-valued differential equations in Banach spaces

    Directory of Open Access Journals (Sweden)

    E. Hanebaly

    2000-03-01

    Full Text Available It is known that for $omega$-periodic differential equations of monotonous type, in uniformly convex Banach spaces, the existence of a bounded solution on ${Bbb R}^+$ is equivalent to the existence of an omega-periodic solution (see Haraux [5] and Hanebaly [7, 10]. It is also known that if the Banach space is strictly convex and the equation is almost periodic and of monotonous type, then the existence of a continuous solution with a precompact range is equivalent to the existence of an almost periodic solution (see Hanebaly [8]. In this note we want to generalize the results above for multi-valued differential equations.

  20. Electromagnetic duality and the electric memory effect

    Science.gov (United States)

    Hamada, Yuta; Seo, Min-Seok; Shiu, Gary

    2018-02-01

    We study large gauge transformations for soft photons in quantum electrodynamics which, together with the helicity operator, form an ISO(2) algebra. We show that the two non-compact generators of the ISO(2) algebra correspond respectively to the residual gauge symmetry and its electromagnetic dual gauge symmetry that emerge at null infinity. The former is helicity universal (electric in nature) while the latter is helicity distinguishing (magnetic in nature). Thus, the conventional large gauge transformation is electric in nature, and is naturally associated with a scalar potential. We suggest that the electric Aharonov-Bohm effect is a direct measure for the electromagnetic memory arising from large gauge transformations.

  1. Memory processing and the glucose facilitation effect: the effects of stimulus difficulty and memory load.

    Science.gov (United States)

    Meikle, Andrew; Riby, Leigh M; Stollery, Brian

    2005-08-01

    Previous research has consistently found enhancement of memory after the ingestion of a glucose containing drink. The aims of the present study were to specify more precisely the nature of this facilitation by examining the cognitive demand hypothesis. This hypothesis predicts greater glucose induced facilitation on tasks that require significant mental effort. In two experiments, both employing an unrelated sample design, participants consumed either 25 g of glucose or a control solution. In experiment 1, participants first studied low and high imagery word-pairs and memory was assessed 1-, 7- and 14-days later by cued recall. Overall, glucose enhanced both encoding and consolidation processes only for the more difficult low imagery pairs. In experiment 2, the degree of mental effort in a verbal memory task was manipulated in two ways: (1) by varying the phonological similarity of the words; and (2) by varying the length of word lists. Glucose was found to enhance memory only for longer word lists. These data are consistent with the idea that glucose is especially effective in demanding memory tasks, but place some limits on the forms of difficulty that are susceptible to enhancement.

  2. Effects of treadmill exercise intensity on spatial working memory and long-term memory in rats.

    Science.gov (United States)

    Wang, Xiao-Qin; Wang, Gong-Wu

    2016-03-15

    Moderate exercise promotes learning and memory. Most studies mainly focused on memory exercise effects of in the ageing and patients. There is lack of quantitative research about effect of regular exercise intensity on different memory types in normal subjects. Present study investigated the effects of different intensities of treadmill exercise on working memory and long-term memory. Fifty female Wistar rats were trained by T-maze delayed spatial alternation (DSA) task with 3 delays (10s, 60s and 300s). Then they got a 30min treadmill exercise for 30days in 4 intensities (control, 0m/min; lower, 15m/min; middle, 20m/min, and higher, 30m/min). Then animals were tested in DSA, passive avoidance and Morris water maze tasks. 1. Exercise increased the neuronal density of hippocampal subregions (CA1, CA3 and dentate gyrus) vs. naïve/control. 2. In DSA task, all groups have similar baseline, lower intensity improved 10s delay accuracy vs. baseline/control; middle and higher intensities improved 300s delay accuracy vs. baseline/control. 3. In water maze learning, all groups successfully found the platform, but middle intensity improved platform field crossing times vs. control in test phase. Present results suggested that treadmill exercise can improve long-term spatial memory and working memory; lower intensity benefits to short-term delayed working memory, and middle or higher intensity benefits to long-term delayed working memory. There was an inverted U dose-effect relationship between exercise intensity and memory performance, but exercise -working memory effect was impacted by delay duration. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. The effect of mild acute stress during memory consolidation on emotional recognition memory.

    Science.gov (United States)

    Corbett, Brittany; Weinberg, Lisa; Duarte, Audrey

    2017-11-01

    Stress during consolidation improves recognition memory performance. Generally, this memory benefit is greater for emotionally arousing stimuli than neutral stimuli. The strength of the stressor also plays a role in memory performance, with memory performance improving up to a moderate level of stress and thereafter worsening. As our daily stressors are generally minimal in strength, we chose to induce mild acute stress to determine its effect on memory performance. In the current study, we investigated if mild acute stress during consolidation improves memory performance for emotionally arousing images. To investigate this, we had participants encode highly arousing negative, minimally arousing negative, and neutral images. We induced stress using the Montreal Imaging Stress Task (MIST) in half of the participants and a control task to the other half of the participants directly after encoding (i.e. during consolidation) and tested recognition 48h later. We found no difference in memory performance between the stress and control group. We found a graded pattern among confidence, with responders in the stress group having the least amount of confidence in their hits and controls having the most. Across groups, we found highly arousing negative images were better remembered than minimally arousing negative or neutral images. Although stress did not affect memory accuracy, responders, as defined by cortisol reactivity, were less confident in their decisions. Our results suggest that the daily stressors humans experience, regardless of their emotional affect, do not have adverse effects on memory. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. The effect of mild acute stress during memory consolidation on emotional recognition memory

    Science.gov (United States)

    Corbett, Brittany; Weinberg, Lisa; Duarte, Audrey

    2018-01-01

    Stress during consolidation improves recognition memory performance. Generally, this memory benefit is greater for emotionally arousing stimuli than neutral stimuli. The strength of the stressor also plays a role in memory performance, with memory performance improving up to a moderate level of stress and thereafter worsening. As our daily stressors are generally minimal in strength, we chose to induce mild acute stress to determine its effect on memory performance. In the current study, we investigated if mild acute stress during consolidation improves memory performance for emotionally arousing images. To investigate this, we had participants encode highly arousing negative, minimally arousing negative, and neutral images. We induced stress using the Montreal Imaging Stress Task (MIST) in half of the participants and a control task to the other half of the participants directly after encoding (i.e. during consolidation) and tested recognition 48 h later. We found no difference in memory performance between the stress and control group. We found a graded pattern among confidence, with responders in the stress group having the least amount of confidence in their hits and controls having the most. Across groups, we found highly arousing negative images were better remembered than minimally arousing negative or neutral images. Although stress did not affect memory accuracy, responders, as defined by cortisol reactivity, were less confident in their decisions. Our results suggest that the daily stressors humans experience, regardless of their emotional affect, do not have adverse effects on memory. PMID:28838881

  5. Memory

    Science.gov (United States)

    ... it has to decide what is worth remembering. Memory is the process of storing and then remembering this information. There are different types of memory. Short-term memory stores information for a few ...

  6. Design of ternary clocked adiabatic static random access memory

    International Nuclear Information System (INIS)

    Wang Pengjun; Mei Fengna

    2011-01-01

    Based on multi-valued logic, adiabatic circuits and the structure of ternary static random access memory (SRAM), a design scheme of a novel ternary clocked adiabatic SRAM is presented. The scheme adopts bootstrapped NMOS transistors, and an address decoder, a storage cell and a sense amplifier are charged and discharged in the adiabatic way, so the charges stored in the large switch capacitance of word lines, bit lines and the address decoder can be effectively restored to achieve energy recovery during reading and writing of ternary signals. The PSPICE simulation results indicate that the ternary clocked adiabatic SRAM has a correct logic function and low power consumption. Compared with ternary conventional SRAM, the average power consumption of the ternary adiabatic SRAM saves up to 68% in the same conditions. (semiconductor integrated circuits)

  7. Design of ternary clocked adiabatic static random access memory

    Science.gov (United States)

    Pengjun, Wang; Fengna, Mei

    2011-10-01

    Based on multi-valued logic, adiabatic circuits and the structure of ternary static random access memory (SRAM), a design scheme of a novel ternary clocked adiabatic SRAM is presented. The scheme adopts bootstrapped NMOS transistors, and an address decoder, a storage cell and a sense amplifier are charged and discharged in the adiabatic way, so the charges stored in the large switch capacitance of word lines, bit lines and the address decoder can be effectively restored to achieve energy recovery during reading and writing of ternary signals. The PSPICE simulation results indicate that the ternary clocked adiabatic SRAM has a correct logic function and low power consumption. Compared with ternary conventional SRAM, the average power consumption of the ternary adiabatic SRAM saves up to 68% in the same conditions.

  8. The time course of working memory effects on visual attention differs depending on memory type

    NARCIS (Netherlands)

    Dombrowe, I.; Olivers, C.N.L.; Donk, M.

    2010-01-01

    Previous work has generated inconsistent results with regard to what extent working memory (WM) content guides visual attention. Some studies found effects of easy to verbalize stimuli, whereas others only found an influence of visual memory content. To resolve this, we compared the time courses of

  9. The effect of rehearsal rate and memory load on verbal working memory.

    Science.gov (United States)

    Fegen, David; Buchsbaum, Bradley R; D'Esposito, Mark

    2015-01-15

    While many neuroimaging studies have investigated verbal working memory (WM) by manipulating memory load, the subvocal rehearsal rate at these various memory loads has generally been left uncontrolled. Therefore, the goal of this study was to investigate how mnemonic load and the rate of subvocal rehearsal modulate patterns of activity in the core neural circuits underlying verbal working memory. Using fMRI in healthy subjects, we orthogonally manipulated subvocal rehearsal rate and memory load in a verbal WM task with long 45-s delay periods. We found that middle frontal gyrus (MFG) and superior parietal lobule (SPL) exhibited memory load effects primarily early in the delay period and did not exhibit rehearsal rate effects. In contrast, we found that inferior frontal gyrus (IFG), premotor cortex (PM) and Sylvian-parietal-temporal region (area Spt) exhibited approximately linear memory load and rehearsal rate effects, with rehearsal rate effects lasting through the entire delay period. These results indicate that IFG, PM and area Spt comprise the core articulatory rehearsal areas involved in verbal WM, while MFG and SPL are recruited in a general supervisory role once a memory load threshold in the core rehearsal network has been exceeded. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Task demands moderate stereotype threat effects on memory performance.

    Science.gov (United States)

    Hess, Thomas M; Emery, Lisa; Queen, Tara L

    2009-06-01

    Previous research has demonstrated that older adults' memory performance is adversely affected by the explicit activation of negative stereotypes about aging. In this study, we examined the impact of stereotype threat on recognition memory, with specific interest in (a) the generalizability of previously observed effects, (b) the subjective experience of memory, and (c) the moderating effects of task demands. Older participants subjected to threat performed worse than did those in a nonthreat condition but only when performance constraints were high (i.e., memory decisions had to be made within a limited time frame). This effect was reflected in the subjective experience of memory, with participants in this condition having a lower ratio of "remember" to "know" responses. The absence of threat effects when constraints were minimal provides important boundary information regarding stereotype influences on memory performance.

  11. Stress effects on memory: an update and integration

    NARCIS (Netherlands)

    Schwabe, L.; Joëls, M.; Roozendaal, B.; Wolf, O.T.; Oitzl, M.S.

    2012-01-01

    It is well known that stressful experiences may affect learning and memory processes. Less clear is the exact nature of these stress effects on memory: both enhancing and impairing effects have been reported. These opposite effects may be explained if the different time courses of stress hormone, in

  12. Stress effects on memory : An update and integration

    NARCIS (Netherlands)

    Schwabe, Lars; Joëls, Marian; Roozendaal, Benno; Wolf, Oliver T.; Oitzl, Melly S.

    It is well known that stressful experiences may affect learning and memory processes. Less clear is the exact nature of these stress effects on memory: both enhancing and impairing effects have been reported. These opposite effects may be explained if the different time courses of stress hormone, in

  13. Suppression effects on musical and verbal memory.

    Science.gov (United States)

    Schendel, Zachary A; Palmer, Caroline

    2007-06-01

    Three experiments contrasted the effects of articulatory suppression on recognition memory for musical and verbal sequences. In Experiment 1, a standard/comparison task was employed, with digit or note sequences presented visually or auditorily while participants remained silent or produced intermittent verbal suppression (saying "the") or musical suppression (singing "la"). Both suppression types decreased performance by equivalent amounts, as compared with no suppression. Recognition accuracy was lower during suppression for visually presented digits than during that for auditorily presented digits (consistent with phonological loop predictions), whereas accuracy was equivalent for visually presented notes and auditory tones. When visual interference filled the retention interval in Experiment 2, performance with visually presented notes but not digits was impaired. Experiment 3 forced participants to translate visually presented music sequences by presenting comparison sequences auditorily. Suppression effects for visually presented music resembled those for digits only when the recognition task required sensory translation of cues.

  14. Magnetic memory effects in high temperature superconductors

    International Nuclear Information System (INIS)

    Rockenbauer, A.

    1989-01-01

    Microwave absorption of high temperature oxide superconductors MBa 2 Cu 3 O 7 (M = Y, Er, Dy, Ho, Lu, Tm, Gd) at 77 K have been studied by ESR. In granular samples diamagnetic zero-field resonance and strong ESR baseline hysteresis have been observed: for increasing field sweep - a high, for decreasing one - a low, while in constant field the baseline approaches the middle position with kinetics typical of spin-glasses. The hysteresis amplitude, i.e. the deviation of high and low baselines, possesses maximum at zero field if the sample is cooled down in zero field. In case of field cooling both the diamagnetic resonance and hysteresis maximum are shifted as a function of relative direction of the fields where the samples are cooled and measured, respectively. The shift is caused by the remanent diamagnetism of trapped fluxons. The hysteresis critically depends on the modulation amplitude of magnetic field, and no hysteresis can be observed if the microwave absorption is detected without field modulation. By applying saw-tooth sweep the spin-glass can be driven between two extreme hysteresis states, and the ESR response is rectangular for large saw-tooth amplitude and linear - for small one, while for intermediate amplitudes the recording shows characteristic memory effects. The hysteresis memory is explained in terms of loop distribution of fluxons. In the single crystal the fluxon absorptions are also detected and the separation of fluxon lines can be related to the hysteresis in granular samples. (author)

  15. A Positive Generation Effect on Memory for Auditory Context.

    Science.gov (United States)

    Overman, Amy A; Richard, Alison G; Stephens, Joseph D W

    2017-06-01

    Self-generation of information during memory encoding has large positive effects on subsequent memory for items, but mixed effects on memory for contextual information associated with items. A processing account of generation effects on context memory (Mulligan in Journal of Experimental Psychology: Learning, Memory, and Cognition, 30(4), 838-855, 2004; Mulligan, Lozito, & Rosner in Journal of Experimental Psychology: Learning, Memory, and Cognition, 32(4), 836-846, 2006) proposes that these effects depend on whether the generation task causes any shift in processing of the type of context features for which memory is being tested. Mulligan and colleagues have used this account to predict various negative effects of generation on context memory, but the account also predicts positive generation effects under certain circumstances. The present experiment provided a critical test of the processing account by examining how generation affected memory for auditory rather than visual context. Based on the processing account, we predicted that generation of rhyme words should enhance processing of auditory information associated with the words (i.e., voice gender), whereas generation of antonym words should have no effect. These predictions were confirmed, providing support to the processing account.

  16. The effects of emotion on memory for music and vocalisations.

    Science.gov (United States)

    Aubé, William; Peretz, Isabelle; Armony, Jorge L

    2013-01-01

    Music is a powerful tool for communicating emotions which can elicit memories through associative mechanisms. However, it is currently unknown whether emotion can modulate memory for music without reference to a context or personal event. We conducted three experiments to investigate the effect of basic emotions (fear, happiness, and sadness) on recognition memory for music, using short, novel stimuli explicitly created for research purposes, and compared them with nonlinguistic vocalisations. Results showed better memory accuracy for musical clips expressing fear and, to some extent, happiness. In the case of nonlinguistic vocalisations we confirmed a memory advantage for all emotions tested. A correlation between memory accuracy for music and vocalisations was also found, particularly in the case of fearful expressions. These results confirm that emotional expressions, particularly fearful ones, conveyed by music can influence memory as has been previously shown for other forms of expressions, such as faces and vocalisations.

  17. Vantage perspective during encoding: The effects on phenomenological memory characteristics.

    Science.gov (United States)

    Mooren, Nora; Krans, Julie; Näring, Gérard W B; Moulds, Michelle L; van Minnen, Agnes

    2016-05-01

    The vantage perspective from which a memory is retrieved influences the memory's emotional impact, intrusiveness, and phenomenological characteristics. This study tested whether similar effects are observed when participants were instructed to imagine the events from a specific perspective. Fifty student participants listened to a verbal report of car-accidents and visualized the scenery from either a field or observer perspective. There were no between-condition differences in emotionality of memories and the number of intrusions, but imagery experienced from a relative observer perspective was rated as less self-relevant. In contrast to earlier studies on memory retrieval, vantage perspective influenced phenomenological memory characteristics of the memory representation such as sensory details, and ratings of vividness and distancing of the memory. However, vantage perspective is most likely not a stable phenomenological characteristic itself. Implications and suggestions for future research are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Assessing the aging effect on auditory-verbal memory by Persian version of dichotic auditory verbal memory test

    Directory of Open Access Journals (Sweden)

    Zahra Shahidipour

    2014-01-01

    Conclusion: Based on the obtained results, significant reduction in auditory memory was seen in aged group and the Persian version of dichotic auditory-verbal memory test, like many other auditory verbal memory tests, showed the aging effects on auditory verbal memory performance.

  19. Environmental context effects in conceptual explicit and implicit memory.

    Science.gov (United States)

    Parker, Andrew; Dagnall, Neil; Coyle, Anne-Marie

    2007-05-01

    Previous research has found environmental context effects for both conceptual explicit and conceptual implicit memory (Parker, Gellatly, & Waterman, 1999). The research presented here challenges these findings on methodological grounds. Experiment 1 assessed the effects of context change on category-exemplar generation (conceptual implicit memory test) and category-cued recall (conceptual explicit memory test). Experiment 2 assessed the effects of context change on word association (conceptual implicit memory test) and word associate cued recall (conceptual explicit memory test). In both experiments, study-test changes in environmental context were found to influence performance only on tests of explicit memory. It is concluded that when retrieval cues across explicit and implicit tests are matched, and the probability of explicit contamination is reduced, then only conceptual explicit test performance is reduced by study-test changes in environmental context.

  20. Effects of Aging on General and Specific Memory for Impressions

    Directory of Open Access Journals (Sweden)

    Megan J. Limbert

    2018-05-01

    Full Text Available Despite the number of documented declines in memory with age, memory for socioemotional information can be preserved into older adulthood. These studies assessed whether memory for character information could be preserved with age, and how the general versus specific nature of the information tested affected outcomes. We hypothesized that memory for general impressions would be preserved with age, but that memory for specific details would be impaired. In two experiments, younger and older adults learned character information about individuals characterized as positive, neutral, or negative. Participants then retrieved general impressions and specific information for each individual. The testing conditions in Experiment 2 discouraged deliberate recall. In Experiment 1, we found that younger performed better than older adults on both general and specific memory measures. Although age differences in memory for specific information persisted in Experiment 2, we found that younger and older adults remembered general impressions to a similar extent when testing conditions encouraged the use of “gut impressions” rather than deliberate retrieval from memory. We conclude that aging affects memory for specific character information, but memory for general impressions can be age-equivalent. Furthermore, there is no evidence for a positivity bias or differences in the effects of valence on memory across the age groups.

  1. Memory Effects of Benzodiazepines: Memory Stages and Types Versus Binding-Site Subtypes

    Directory of Open Access Journals (Sweden)

    Miroslav M. Savic

    2005-01-01

    Full Text Available Benzodiazepines are well established as inhibitory modulators of memory processing. This effect is especially prominent when applied before the acquisition phase of a memory task. This minireview concentrates on the putative subtype selectivity of the acquisition-impairing action of benzodiazepines. Namely, recent genetic studies and standard behavioral tests employing subtype-selective ligands pointed to the predominant involvement of two subtypes of benzodiazepine binding sites in memory modulation. Explicit memory learning seems to be affected through the GABAA receptors containing the α1 and α5 subunits, whereas the effects on procedural memory can be mainly mediated by the α1 subunit. The pervading involvement of the α1 subunit in memory modulation is not at all unexpected because this subunit is the major subtype, present in 60% of all GABAA receptors. On the other hand, the role of α5 subunits, mainly expressed in the hippocampus, in modulating distinct forms of memory gives promise of selective pharmacological coping with certain memory deficit states.

  2. Time and interference: Effects on working memory.

    Science.gov (United States)

    Botto, Marta; Palladino, Paola

    2016-05-01

    This study tested predictions from the time-based resource-sharing (TBRS) model with a classical verbal working memory (WM) task, where target and non-target information interfere strongly with each other. Different predictions can be formulated according to the dominant perspectives (TBRS and interference hypothesis) on the role of inhibitory control in WM task performance. Here, we aimed to trace the activation of irrelevant information, examining priming effects in a lexical decision task immediately following WM recall. Results indicate the roles of both time and interference constraints in determining task performance. In particular, the role of time available seemed crucial at the highest WM loads (i.e., 3 and 4 memoranda). These were also associated with a higher activation of no-longer-relevant information but, in this case, independently from time available for processing. © 2015 The British Psychological Society.

  3. Communication: Memory effects and active Brownian diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Pulak K. [Department of Chemistry, Presidency University, Kolkata 700073 (India); Li, Yunyun, E-mail: yunyunli@tongji.edu.cn [Center for Phononics and Thermal Energy Science, Tongji University, Shanghai 200092 (China); Marchegiani, Giampiero [Dipartimento di Fisica, Università di Camerino, I-62032 Camerino (Italy); Marchesoni, Fabio [Center for Phononics and Thermal Energy Science, Tongji University, Shanghai 200092 (China); Dipartimento di Fisica, Università di Camerino, I-62032 Camerino (Italy)

    2015-12-07

    A self-propelled artificial microswimmer is often modeled as a ballistic Brownian particle moving with constant speed aligned along one of its axis, but changing direction due to random collisions with the environment. Similarly to thermal noise, its angular randomization is described as a memoryless stochastic process. Here, we speculate that finite-time correlations in the orientational dynamics can affect the swimmer’s diffusivity. To this purpose, we propose and solve two alternative models. In the first one, we simply assume that the environmental fluctuations governing the swimmer’s propulsion are exponentially correlated in time, whereas in the second one, we account for possible damped fluctuations of the propulsion velocity around the swimmer’s axis. The corresponding swimmer’s diffusion constants are predicted to get, respectively, enhanced or suppressed upon increasing the model memory time. Possible consequences of this effect on the interpretation of the experimental data are discussed.

  4. The Effect of Shape Memory on Red Blood Cell Motions

    Science.gov (United States)

    Niu, Xiting; Shi, Lingling; Pan, Tsorng-Whay; Glowinski, Roland

    2013-11-01

    An elastic spring model is applied to study the effect of the shape memory on the motion of red blood cell in flows. In shear flow, shape memory also plays an important role to obtain all three motions: tumbling, swinging, and tank-treading. In Poiseuille flow, cell has an equilibrium shape as a slipper or parachute depending on capillary number. To ensure the tank-treading motion while in slippery shape, a modified model is proposed by introducing a shape memory coefficient which describes the degree of shape memory in cells. The effect of the coefficient on the cell motion of red blood cell will be presented.

  5. The effects of free recall testing on subsequent source memory.

    Science.gov (United States)

    Brewer, Gene A; Marsh, Richard L; Meeks, Joseph T; Clark-Foos, Arlo; Hicks, Jason L

    2010-05-01

    The testing effect is the finding that prior retrieval of information from memory will result in better subsequent memory for that material. One explanation for these effects is that initial free recall testing increases the recollective details for tested information, which then becomes more available during a subsequent test phase. In three experiments we explored this hypothesis using a source-monitoring test phase after the initial free recall tests. We discovered that memory is differentially enhanced for certain recollective details depending on the nature of the free recall task. Thus further research needs to be conducted to specify how different kinds of memorial details are enhanced by free recall testing.

  6. Word Length Effects in Long-Term Memory

    Science.gov (United States)

    Tehan, Gerald; Tolan, Georgina Anne

    2007-01-01

    The word length effect has been a central feature of theorising about immediate memory. The notion that short-term memory traces rapidly decay unless refreshed by rehearsal is based primarily upon the finding that serial recall for short words is better than that for long words. The decay account of the word length effect has come under pressure…

  7. The memory effect for particle scattering in even spacetime dimensions

    Science.gov (United States)

    Garfinkle, David; Hollands, Stefan; Ishibashi, Akihiro; Tolish, Alexander; Wald, Robert M.

    2017-07-01

    We explicitly calculate the gravitational wave memory effect for classical point particle sources in linearized gravity off an even dimensional Minkowski background. We show that there is no memory effect in d  >  4 dimensions, in agreement with the general analysis of Hollands et al (2016 arXiv:1612.03290).

  8. The Effects of Motoric Action and Organization on Children's Memory.

    Science.gov (United States)

    Heindel, Patricia; Kose, Gary

    1990-01-01

    Two experiments examined preschool, first, and third grade students for the effects of motoric activities on memory performance. Findings for the first experiment revealed that, although organizational differences affected memory performance, the drawing of configurations enhanced the effect of unitary organization. In the second experiment,…

  9. Memory bias for negative emotional words in recognition memory is driven by effects of category membership.

    Science.gov (United States)

    White, Corey N; Kapucu, Aycan; Bruno, Davide; Rotello, Caren M; Ratcliff, Roger

    2014-01-01

    Recognition memory studies often find that emotional items are more likely than neutral items to be labelled as studied. Previous work suggests this bias is driven by increased memory strength/familiarity for emotional items. We explored strength and bias interpretations of this effect with the conjecture that emotional stimuli might seem more familiar because they share features with studied items from the same category. Categorical effects were manipulated in a recognition task by presenting lists with a small, medium or large proportion of emotional words. The liberal memory bias for emotional words was only observed when a medium or large proportion of categorised words were presented in the lists. Similar, though weaker, effects were observed with categorised words that were not emotional (animal names). These results suggest that liberal memory bias for emotional items may be largely driven by effects of category membership.

  10. Assessing the aging effect on auditory-verbal memory by Persian version of dichotic auditory verbal memory test

    OpenAIRE

    Zahra Shahidipour; Ahmad Geshani; Zahra Jafari; Shohreh Jalaie; Elham Khosravifard

    2014-01-01

    Background and Aim: Memory is one of the aspects of cognitive function which is widely affected among aged people. Since aging has different effects on different memorial systems and little studies have investigated auditory-verbal memory function in older adults using dichotic listening techniques, the purpose of this study was to evaluate the auditory-verbal memory function among old people using Persian version of dichotic auditory-verbal memory test. Methods: The Persian version of dic...

  11. Shape memory effect and super elasticity. Its dental applications.

    Science.gov (United States)

    Kotian, R

    2001-01-01

    The shape memory alloys are quite fascinating materials characterized by a shape memory effect and super elasticity which ordinary metals do not have. This unique behaviour was first found in a Au-47.5 at % Cd alloy in 1951, and was published in 1963 by the discovery of Ti-Ni alloy. Shape memory alloys now being practically used as new functional alloys for various dental and medical applications.

  12. Parallel effects of memory set activation and searchon timing and working memory capacity

    Directory of Open Access Journals (Sweden)

    Richard eSchweickert

    2014-07-01

    Full Text Available Accurately estimating a time interval is required in everyday activities such as driving or cooking. Estimating time is relatively easy, provided a person attends to it. But a brief shift of attention to another task usually interferes with timing. Most processes carried out concurrently with timing interfere with it. Curiously, some do not. Literature on a few processes suggests a general proposition, the Timing and Complex-Span Hypothesis: A process interferes with concurrent timing if and only if process performance is related to complex span. Complex-span is the number of items correctly recalled in order, when each item presented for study is followed by a brief activity. Literature on task switching, visual search, memory search, word generation and mental time travel supports the hypothesis. Previous work found that another process, activation of a memory set in long term memory, is not related to complex-span. If the Timing and Complex-Span Hypothesis is true, activation should not interfere with concurrent timing in dual-task conditions. We tested such activation in single-task memory search task conditions and in dual-task conditions where memory search was executed with concurrent timing. In Experiment 1, activating a memory set increased reaction time, with no significant effect on time production. In Experiment 2, set size and memory set activation were manipulated. Activation and set size had a puzzling interaction for time productions, perhaps due to difficult conditions, leading us to use a related but easier task in Experiment 3. In Experiment 3 increasing set size lengthened time production, but memory activation had no significant effect. Results here and in previous literature on the whole support the Timing and Complex-Span Hypotheses. Results also support a sequential organization of activation and search of memory. This organization predicts activation and set size have additive effects on reaction time and multiplicative

  13. Parallel effects of memory set activation and search on timing and working memory capacity.

    Science.gov (United States)

    Schweickert, Richard; Fortin, Claudette; Xi, Zhuangzhuang; Viau-Quesnel, Charles

    2014-01-01

    Accurately estimating a time interval is required in everyday activities such as driving or cooking. Estimating time is relatively easy, provided a person attends to it. But a brief shift of attention to another task usually interferes with timing. Most processes carried out concurrently with timing interfere with it. Curiously, some do not. Literature on a few processes suggests a general proposition, the Timing and Complex-Span Hypothesis: A process interferes with concurrent timing if and only if process performance is related to complex span. Complex-span is the number of items correctly recalled in order, when each item presented for study is followed by a brief activity. Literature on task switching, visual search, memory search, word generation and mental time travel supports the hypothesis. Previous work found that another process, activation of a memory set in long term memory, is not related to complex-span. If the Timing and Complex-Span Hypothesis is true, activation should not interfere with concurrent timing in dual-task conditions. We tested such activation in single-task memory search task conditions and in dual-task conditions where memory search was executed with concurrent timing. In Experiment 1, activating a memory set increased reaction time, with no significant effect on time production. In Experiment 2, set size and memory set activation were manipulated. Activation and set size had a puzzling interaction for time productions, perhaps due to difficult conditions, leading us to use a related but easier task in Experiment 3. In Experiment 3 increasing set size lengthened time production, but memory activation had no significant effect. Results here and in previous literature on the whole support the Timing and Complex-Span Hypotheses. Results also support a sequential organization of activation and search of memory. This organization predicts activation and set size have additive effects on reaction time and multiplicative effects on percent

  14. Effects of mild cognitive impairment on emotional scene memory.

    Science.gov (United States)

    Waring, J D; Dimsdale-Zucker, H R; Flannery, S; Budson, A E; Kensinger, E A

    2017-02-01

    Young and older adults experience benefits in attention and memory for emotional compared to neutral information, but this memory benefit is greatly diminished in Alzheimer's disease (AD). Little is known about whether this impairment arises early or late in the time course between healthy aging and AD. This study compared memory for positive, negative, and neutral items with neutral backgrounds between patients with mild cognitive impairment (MCI) and healthy older adults. We also used a divided attention condition in older adults as a possible model for the deficits observed in MCI patients. Results showed a similar pattern of selective memory for emotional items while forgetting their backgrounds in older adults and MCI patients, but MCI patients had poorer memory overall. Dividing attention during encoding disproportionately reduced memory for backgrounds (versus items) relative to a full attention condition. Participants performing in the lower half on the divided attention task qualitatively and quantitatively mirrored the results in MCI patients. Exploratory analyses comparing lower- and higher-performing MCI patients showed that only higher-performing MCI patients had the characteristic scene memory pattern observed in healthy older adults. Together, these results suggest that the effects of emotion on memory are relatively well preserved for patients with MCI, although emotional memory patterns may start to be altered once memory deficits become more pronounced. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Non-volatile memory based on the ferroelectric photovoltaic effect

    Science.gov (United States)

    Guo, Rui; You, Lu; Zhou, Yang; Shiuh Lim, Zhi; Zou, Xi; Chen, Lang; Ramesh, R.; Wang, Junling

    2013-01-01

    The quest for a solid state universal memory with high-storage density, high read/write speed, random access and non-volatility has triggered intense research into new materials and novel device architectures. Though the non-volatile memory market is dominated by flash memory now, it has very low operation speed with ~10 μs programming and ~10 ms erasing time. Furthermore, it can only withstand ~105 rewriting cycles, which prevents it from becoming the universal memory. Here we demonstrate that the significant photovoltaic effect of a ferroelectric material, such as BiFeO3 with a band gap in the visible range, can be used to sense the polarization direction non-destructively in a ferroelectric memory. A prototype 16-cell memory based on the cross-bar architecture has been prepared and tested, demonstrating the feasibility of this technique. PMID:23756366

  16. Shape memory polymer hybrids of SBS/dl-PLA and their shape memory effects

    International Nuclear Information System (INIS)

    Zhang, Heng; Chen, Zhi; Zheng, Zheng; Zhu, Xiaomin; Wang, Haitao

    2013-01-01

    The hybrids of styrene-butadiene-styrene tri-block copolymer (SBS) and amorphous poly(dl-lactic acid) (dl-PLA) are found to exhibit shape memory effects, which gives an example of a dual-domain shape memory system consisting of an elastic domain and a thermo-switch domain. The dual-domain manner in this hybrid is studied by means of differential scanning calorimetry (DSC) and scanning electron microscope (SEM). Subsequently, the tensile test clarifies the interactions of the two domains on shape memory effects. As an elastic domain, SBS offers good shape recovery when its content exceeds 50 wt%. As a thermo-switch domain, dl-PLA triggers the shape memory effect at ca. 55 °C and offers good shape fixing when the content exceeds 30 wt%. An easy-to-do and easy-to-know feature of the hybrid is that the optimization of shape memory effect can be achieved by generating bicontinous phases of SBS and dl-PLA, in which the dl-PLA content ranges from 30 to 70 wt%. -- Highlights: ► The composite materials of SBS and amorphous dl-PLA were prepared by blending. ► A continuous domain was observed with the increasing content of dl-PLA. ► The composites exhibited shape memory effects.

  17. Multi-valued logic gates based on ballistic transport in quantum point contacts.

    Science.gov (United States)

    Seo, M; Hong, C; Lee, S-Y; Choi, H K; Kim, N; Chung, Y; Umansky, V; Mahalu, D

    2014-01-22

    Multi-valued logic gates, which can handle quaternary numbers as inputs, are developed by exploiting the ballistic transport properties of quantum point contacts in series. The principle of a logic gate that finds the minimum of two quaternary number inputs is demonstrated. The device is scalable to allow multiple inputs, which makes it possible to find the minimum of multiple inputs in a single gate operation. Also, the principle of a half-adder for quaternary number inputs is demonstrated. First, an adder that adds up two quaternary numbers and outputs the sum of inputs is demonstrated. Second, a device to express the sum of the adder into two quaternary digits [Carry (first digit) and Sum (second digit)] is demonstrated. All the logic gates presented in this paper can in principle be extended to allow decimal number inputs with high quality QPCs.

  18. Multi-Valued Logic Gates based on Ballistic Transport in Quantum Point Contacts

    Science.gov (United States)

    Seo, M.; Hong, C.; Lee, S.-Y.; Choi, H. K.; Kim, N.; Chung, Y.; Umansky, V.; Mahalu, D.

    2014-01-01

    Multi-valued logic gates, which can handle quaternary numbers as inputs, are developed by exploiting the ballistic transport properties of quantum point contacts in series. The principle of a logic gate that finds the minimum of two quaternary number inputs is demonstrated. The device is scalable to allow multiple inputs, which makes it possible to find the minimum of multiple inputs in a single gate operation. Also, the principle of a half-adder for quaternary number inputs is demonstrated. First, an adder that adds up two quaternary numbers and outputs the sum of inputs is demonstrated. Second, a device to express the sum of the adder into two quaternary digits [Carry (first digit) and Sum (second digit)] is demonstrated. All the logic gates presented in this paper can in principle be extended to allow decimal number inputs with high quality QPCs.

  19. Approximation Of Multi-Valued Inverse Functions Using Clustering And Sugeno Fuzzy Inference

    Science.gov (United States)

    Walden, Maria A.; Bikdash, Marwan; Homaifar, Abdollah

    1998-01-01

    Finding the inverse of a continuous function can be challenging and computationally expensive when the inverse function is multi-valued. Difficulties may be compounded when the function itself is difficult to evaluate. We show that we can use fuzzy-logic approximators such as Sugeno inference systems to compute the inverse on-line. To do so, a fuzzy clustering algorithm can be used in conjunction with a discriminating function to split the function data into branches for the different values of the forward function. These data sets are then fed into a recursive least-squares learning algorithm that finds the proper coefficients of the Sugeno approximators; each Sugeno approximator finds one value of the inverse function. Discussions about the accuracy of the approximation will be included.

  20. Visualization and processing of higher order descriptors for multi-valued data

    CERN Document Server

    Schultz, Thomas

    2015-01-01

    Modern imaging techniques and computational simulations yield complex multi-valued data that require higher-order mathematical descriptors. This book addresses topics of importance when dealing with such data, including frameworks for image processing, visualization, and statistical analysis of higher-order descriptors. It also provides examples of the successful use of higher-order descriptors in specific applications and a glimpse of the next generation of diffusion MRI. To do so, it combines contributions on new developments, current challenges in this area, and state-of-the-art surveys.   Compared to the increasing importance of higher-order descriptors in a range of applications, tools for analysis and processing are still relatively hard to come by. Even though application areas such as medical imaging, fluid dynamics, and structural mechanics are very different in nature they face many shared challenges. This book provides an interdisciplinary perspective on this topic with contributions from key rese...

  1. Anchoring effects on early autobiographical memories.

    Science.gov (United States)

    Greenberg, Daniel L; Bishara, Anthony J; Mugayar-Baldocchi, Marino A

    2017-10-01

    Studies of childhood memory typically show that our earliest memories come from between three and four years of age. This finding is not universal, however. The age estimate varies across cultures and is affected by social influences. Research from the judgments and decision-making literature suggests that these estimates might also involve a judgment under uncertainty. Therefore, they might be susceptible to less social influences such as heuristics and biases. To investigate this possibility, we conducted two experiments that used anchoring paradigms to influence participants' estimates of their age during early autobiographical memories. In Experiment 1, participants answered either a high-anchor or a low-anchor question, and were warned that the anchor was uninformative; they went on to estimate their age during their earliest autobiographical memory. In Experiment 2, we replicated Experiment 1 and extended the design to examine additional early autobiographical memories. In both experiments, participants in the low-anchor condition gave earlier age estimates than those in the high-anchor condition. These results provide new insights into the methods used to investigate autobiographical memory. Moreover, they show that reports of early autobiographical memories can be influenced by a relatively light touch - a change to a single digit in a single question.

  2. Sentence Complexity and Working Memory Effects in Ambiguity Resolution

    Science.gov (United States)

    Kim, Ji Hyon; Christianson, Kiel

    2013-01-01

    Two self-paced reading experiments using a paraphrase decision task paradigm were performed to investigate how sentence complexity contributed to the relative clause (RC) attachment preferences of speakers of different working memory capacities (WMCs). Experiment 1 (English) showed working memory effects on relative clause processing in both…

  3. Effects of Aging and Education on False Memory

    Science.gov (United States)

    Lee, Yuh-Shiow; Lee, Chia-Lin; Yang, Hua-Te

    2012-01-01

    This study examined the effects of aging and education on participants' false memory for words that were not presented. Three age groups of participants with either a high or low education level were asked to study lists of semantically related words. Both age and education were found to affect veridical and false memory, as indicated in the…

  4. Revisiting the Novelty Effect: When Familiarity, Not Novelty, Enhances Memory

    Science.gov (United States)

    Poppenk, J.; Kohler, S.; Moscovitch, M.

    2010-01-01

    Reports of superior memory for novel relative to familiar material have figured prominently in recent theories of memory. However, such "novelty effects" are incongruous with long-standing observations that familiar items are remembered better. In 2 experiments, we explored whether this discrepancy was explained by differences in the…

  5. Effects of Music Notation Reinforcement on Aural Memory for Melodies

    Science.gov (United States)

    Buonviri, Nathan

    2015-01-01

    The purpose of this study was to investigate effects of music notation reinforcement on aural memory for melodies. Participants were 41 undergraduate and graduate music majors in a within-subjects design. Experimental trials tested melodic memory through a sequence of target melodies, distraction melodies, and matched and unmatched answer choices.…

  6. Memory effects in relativistic heavy ion collisions

    International Nuclear Information System (INIS)

    Greiner, C.; Wagner, K.; Reinhard, P.

    1994-01-01

    We consider equilibration in relativistic nuclear dynamics starting from a nonequilibrium Green's-functions approach. The widely used Boltzmann-Uehling-Uhlenbeck equation is obtained only as the Markovian limit (i.e., negligible memory time). The actual memory time in energetic nuclear collisions turns out to be ∼2--3 fm/c, which interferes substantially with the time scale of the relaxation process. The memory kernels of the collision process will be presented. Because of their more involved structure, depending sensitively on the kinematical regime, both less and more stopping power is observed in the reaction compared to the Markovian description

  7. The Effects of Valence and Arousal on Associative Working Memory and Long-Term Memory

    Science.gov (United States)

    Bergmann, Heiko C.; Rijpkema, Mark; Fernández, Guillén; Kessels, Roy P. C.

    2012-01-01

    Background Emotion can either facilitate or impair memory, depending on what, when and how memory is tested and whether the paradigm at hand is administered as a working memory (WM) or a long-term memory (LTM) task. Whereas emotionally arousing single stimuli are more likely to be remembered, memory for the relationship between two or more component parts (i.e., relational memory) appears to be worse in the presence of emotional stimuli, at least in some relational memory tasks. The current study investigated the effects of both valence (neutral vs. positive vs. negative) and arousal (low vs. high) in an inter-item WM binding and LTM task. Methodology/Principal Findings A five-pair delayed-match-to-sample (WM) task was administered. In each trial, study pairs consisted of one neutral picture and a second picture of which the emotional qualities (valence and arousal levels) were manipulated. These pairs had to be remembered across a delay interval of 10 seconds. This was followed by a probe phase in which five pairs were tested. After completion of this task, an unexpected single item LTM task as well as an LTM task for the pairs was assessed. As expected, emotional arousal impaired WM processing. This was reflected in lower accuracy for pairs consisting of high-arousal pictures compared to pairs with low-arousal pictures. A similar effect was found for the associative LTM task. However, the arousal effect was modulated by affective valence for the WM but not the LTM task; pairs with low-arousal negative pictures were not processed as well in the WM task. No significant differences were found for the single-item LTM task. Conclusions/Significance The present study provides additional evidence that processes during initial perception/encoding and post-encoding processes, the time interval between study and test and the interaction between valence and arousal might modulate the effects of “emotion” on associative memory. PMID:23300724

  8. Memory color effect induced by familiarity of brand logos.

    Science.gov (United States)

    Kimura, Atsushi; Wada, Yuji; Masuda, Tomohiro; Goto, Sho-Ichi; Tsuzuki, Daisuke; Hibino, Haruo; Cai, Dongsheng; Dan, Ippeita

    2013-01-01

    When people are asked to adjust the color of familiar objects such as fruits until they appear achromatic, the subjective gray points of the objects are shifted away from the physical gray points in a direction opposite to the memory color (memory color effect). It is still unclear whether the discrepancy between memorized and actual colors of objects is dependent on the familiarity of the objects. Here, we conducted two experiments in order to examine the relationship between the degree of a subject's familiarity with objects and the degree of the memory color effect by using logographs of food and beverage companies. In Experiment 1, we measured the memory color effects of logos which varied in terms of their familiarity (high, middle, or low). Results demonstrate that the memory color effect occurs only in the high-familiarity condition, but not in the middle- and low-familiarity conditions. Furthermore, there is a positive correlation between the memory color effect and the actual number of domestic stores of the brand. In Experiment 2, we assessed the semantic association between logos and food/beverage names by using a semantic priming task to elucidate whether the memory color effect of logos relates to consumer brand cognition, and found that the semantic associations between logos and food/beverage names in the high-familiarity brands were stronger than those in the low-familiarity brands only when the logos were colored correctly, but not when they were appropriately or inappropriately colored, or achromatic. The current results provide behavioral evidence of the relationship between the familiarity of objects and the memory color effect and suggest that the memory color effect increases with the familiarity of objects, albeit not constantly.

  9. Memory Color Effect Induced by Familiarity of Brand Logos

    Science.gov (United States)

    Kimura, Atsushi; Wada, Yuji; Masuda, Tomohiro; Goto, Sho-ichi; Tsuzuki, Daisuke; Hibino, Haruo; Cai, Dongsheng; Dan, Ippeita

    2013-01-01

    Background When people are asked to adjust the color of familiar objects such as fruits until they appear achromatic, the subjective gray points of the objects are shifted away from the physical gray points in a direction opposite to the memory color (memory color effect). It is still unclear whether the discrepancy between memorized and actual colors of objects is dependent on the familiarity of the objects. Here, we conducted two experiments in order to examine the relationship between the degree of a subject’s familiarity with objects and the degree of the memory color effect by using logographs of food and beverage companies. Methods and Findings In Experiment 1, we measured the memory color effects of logos which varied in terms of their familiarity (high, middle, or low). Results demonstrate that the memory color effect occurs only in the high-familiarity condition, but not in the middle- and low-familiarity conditions. Furthermore, there is a positive correlation between the memory color effect and the actual number of domestic stores of the brand. In Experiment 2, we assessed the semantic association between logos and food/beverage names by using a semantic priming task to elucidate whether the memory color effect of logos relates to consumer brand cognition, and found that the semantic associations between logos and food/beverage names in the high-familiarity brands were stronger than those in the low-familiarity brands only when the logos were colored correctly, but not when they were appropriately or inappropriately colored, or achromatic. Conclusion The current results provide behavioral evidence of the relationship between the familiarity of objects and the memory color effect and suggest that the memory color effect increases with the familiarity of objects, albeit not constantly. PMID:23874638

  10. Memory color effect induced by familiarity of brand logos.

    Directory of Open Access Journals (Sweden)

    Atsushi Kimura

    Full Text Available When people are asked to adjust the color of familiar objects such as fruits until they appear achromatic, the subjective gray points of the objects are shifted away from the physical gray points in a direction opposite to the memory color (memory color effect. It is still unclear whether the discrepancy between memorized and actual colors of objects is dependent on the familiarity of the objects. Here, we conducted two experiments in order to examine the relationship between the degree of a subject's familiarity with objects and the degree of the memory color effect by using logographs of food and beverage companies.In Experiment 1, we measured the memory color effects of logos which varied in terms of their familiarity (high, middle, or low. Results demonstrate that the memory color effect occurs only in the high-familiarity condition, but not in the middle- and low-familiarity conditions. Furthermore, there is a positive correlation between the memory color effect and the actual number of domestic stores of the brand. In Experiment 2, we assessed the semantic association between logos and food/beverage names by using a semantic priming task to elucidate whether the memory color effect of logos relates to consumer brand cognition, and found that the semantic associations between logos and food/beverage names in the high-familiarity brands were stronger than those in the low-familiarity brands only when the logos were colored correctly, but not when they were appropriately or inappropriately colored, or achromatic.The current results provide behavioral evidence of the relationship between the familiarity of objects and the memory color effect and suggest that the memory color effect increases with the familiarity of objects, albeit not constantly.

  11. Memory effect o force measurements at nanoscales

    International Nuclear Information System (INIS)

    Lisy, V.; Tothova, J.

    2011-01-01

    we have obtained an exact solution for the drift velocity of a Brownian particle in an incompressible fluid under the action of a constant force, taking into account the hydrodynamic memory in the particle motion. This velocity is proportional to the applied force but depends in a complicated manner on the time of observation t. At short times it is proportional to t and at long times it contains algebraic tails, the longest-lived of which being ∼ t -1/ 2. Due to this the velocity very slowly approaches the limiting value F/γ. As a consequence, the force F can significantly differ from the value that would be extracted from the drift measurements neglecting the inertial effects, which is a standard assumption in the interpretation of such experiments. The presented method can be equally applicable in the case of force linearly depending on the particle position. For nonlinear forces, first the open question about the choice of convention to be used in stochastic calculus should be resolved. (authors)

  12. A Bayesian Model of the Memory Colour Effect.

    Science.gov (United States)

    Witzel, Christoph; Olkkonen, Maria; Gegenfurtner, Karl R

    2018-01-01

    According to the memory colour effect, the colour of a colour-diagnostic object is not perceived independently of the object itself. Instead, it has been shown through an achromatic adjustment method that colour-diagnostic objects still appear slightly in their typical colour, even when they are colourimetrically grey. Bayesian models provide a promising approach to capture the effect of prior knowledge on colour perception and to link these effects to more general effects of cue integration. Here, we model memory colour effects using prior knowledge about typical colours as priors for the grey adjustments in a Bayesian model. This simple model does not involve any fitting of free parameters. The Bayesian model roughly captured the magnitude of the measured memory colour effect for photographs of objects. To some extent, the model predicted observed differences in memory colour effects across objects. The model could not account for the differences in memory colour effects across different levels of realism in the object images. The Bayesian model provides a particularly simple account of memory colour effects, capturing some of the multiple sources of variation of these effects.

  13. Motivated reconstruction: The effect of brand commitment on false memories.

    Science.gov (United States)

    Montgomery, Nicole Votolato; Rajagopal, Priyali

    2018-06-01

    Across 5 studies, we examine the effect of prior brand commitment on the creation of false memories about product experience after reading online product reviews. We find that brand commitment and the valence of reviews to which consumers are exposed, interact to affect the incidence of false memories. Thus, highly committed consumers are more susceptible to the creation of false experience memories on exposure to positive versus negative reviews, whereas low commitment consumers exhibit similar levels of false memories in response to both positive and negative reviews. Further, these differences across brand commitment are attenuated when respondents are primed with an accuracy motivation, suggesting that the biasing effects of commitment are likely because of the motivation to defend the committed brand. Finally, we find that differences in false memories subsequently lead to differences in intentions to spread word-of-mouth (e.g., recommend the product to friends), suggesting that the consequences of false product experience memories can be significant for marketers and consumers. Our findings contribute to the literatures in false memory and marketing by documenting a motivated bias in false memories because of brand commitment. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  14. The Cost of Learning: Interference Effects in Memory Development

    Science.gov (United States)

    Darby, Kevin P.; Sloutsky, Vladimir M.

    2015-01-01

    Learning often affects future learning and memory for previously learned information by exerting either facilitation or interference effects. Several theoretical accounts of interference effects have been proposed, each making different developmental predictions. This research examines interference effects across development, with the goal of better understanding mechanisms of interference and of memory development. Preschool-aged children and adults participated in a three-phased associative learning paradigm containing stimuli that were either unique or repeated across phases. Both age groups demonstrated interference effects, but only for repeated items. Whereas proactive interference effects were comparable across age groups, retroactive interference reached catastrophic-like levels in children. Additionally, retroactive interference increased in adults when contextual differences between phases were minimized (Experiment 2), and decreased in adults who were more successful at encoding repeated pairs of stimuli during a training phase (Experiment 3). These results are discussed with respect to theories of memory and memory development. PMID:25688907

  15. With sadness comes accuracy; with happiness, false memory: mood and the false memory effect.

    Science.gov (United States)

    Storbeck, Justin; Clore, Gerald L

    2005-10-01

    The Deese-Roediger-McDermott paradigm lures people to produce false memories. Two experiments examined whether induced positive or negative moods would influence this false memory effect. The affect-as-information hypothesis predicts that, on the one hand, positive affective cues experienced as task-relevant feedback encourage relational processing during encoding, which should enhance false memory effects. On the other hand, negative affective cues are hypothesized to encourage item-specific processing at encoding, which should discourage such effects. The results of Experiment 1 are consistent with these predictions: Individuals in negative moods were significantly less likely to show false memory effects than those in positive moods or those whose mood was not manipulated. Experiment 2 introduced inclusion instructions to investigate whether moods had their effects at encoding or retrieval. The results replicated the false memory finding of Experiment 1 and provide evidence that moods influence the accessibility of lures at encoding, rather than influencing monitoring at retrieval of whether lures were actually presented.

  16. Shattered illusions: the effect of explicit memory mediation on an indirect memory test.

    Science.gov (United States)

    Gooding, P A; Mayes, A R; Meudell, P R

    1999-05-01

    Four experiments were conducted to explore the possible involvement of explicit memory in an indirect memory test in which white noise accompanying old sentences was judged to be quieter than white noise accompanying new sentences (Jacoby, Allan, Collins & Larwill, 1988). Experiment 1 established that this effect lasted up to 1 week. Experiment 2 found that a group of amnesic patients showed a noise effect that was marginally above chance and not significantly less that that of their matched controls after a delay of one day. Effect of time pressure at test (Experiment 3) and divided attention at study (Experiment 4) suggested that the memory processes mediating the noise effect were not automatic, although the possibility that the processes involve enhanced fluency is also discussed.

  17. Differential effects of arousal in positive and negative autobiographical memories.

    Science.gov (United States)

    Ford, Jaclyn Hennessey; Addis, Donna Rose; Giovanello, Kelly S

    2012-01-01

    Autobiographical memories are characterised by a range of emotions and emotional reactions. Recent research has demonstrated that differences in emotional valence (positive vs. negative emotion) and arousal (the degree of emotional intensity) differentially influence the retrieved memory narrative. Although the mnemonic effects of valence and arousal have both been heavily studied, it is currently unclear whether the effects of emotional arousal are equivalent for positive and negative autobiographical events. In the current study, multilevel models were used to examine differential effects of emotional valence and arousal on the richness of autobiographical memory retrieval both between and within subjects. Thirty-four young adults were asked to retrieve personal autobiographical memories associated with popular musical cues and to rate the valence, arousal and richness of these events. The multilevel analyses identified independent influences of valence and intensity upon retrieval characteristics at the within- and between-subject levels. In addition, the within-subject interactions between valence and arousal highlighted differential effects of arousal for positive and negative memories. These findings have important implications for future studies of emotion and memory, highlighting the importance of considering both valence and arousal when examining the role emotion plays in the richness of memory representation.

  18. Prospective memory: effects of divided attention on spontaneous retrieval.

    Science.gov (United States)

    Harrison, Tyler L; Mullet, Hillary G; Whiffen, Katie N; Ousterhout, Hunter; Einstein, Gilles O

    2014-02-01

    We examined the effects of divided attention on the spontaneous retrieval of a prospective memory intention. Participants performed an ongoing lexical decision task with an embedded prospective memory demand, and also performed a divided-attention task during some segments of lexical decision trials. In all experiments, monitoring was highly discouraged, and we observed no evidence that participants engaged monitoring processes. In Experiment 1, performing a moderately demanding divided-attention task (a digit detection task) did not affect prospective memory performance. In Experiment 2, performing a more challenging divided-attention task (random number generation) impaired prospective memory. Experiment 3 showed that this impairment was eliminated when the prospective memory cue was perceptually salient. Taken together, the results indicate that spontaneous retrieval is not automatic and that challenging divided-attention tasks interfere with spontaneous retrieval and not with the execution of a retrieved intention.

  19. Effects of timbre and tempo change on memory for music.

    Science.gov (United States)

    Halpern, Andrea R; Müllensiefen, Daniel

    2008-09-01

    We investigated the effects of different encoding tasks and of manipulations of two supposedly surface parameters of music on implicit and explicit memory for tunes. In two experiments, participants were first asked to either categorize instrument or judge familiarity of 40 unfamiliar short tunes. Subsequently, participants were asked to give explicit and implicit memory ratings for a list of 80 tunes, which included 40 previously heard. Half of the 40 previously heard tunes differed in timbre (Experiment 1) or tempo (Experiment 2) in comparison with the first exposure. A third experiment compared similarity ratings of the tunes that varied in timbre or tempo. Analysis of variance (ANOVA) results suggest first that the encoding task made no difference for either memory mode. Secondly, timbre and tempo change both impaired explicit memory, whereas tempo change additionally made implicit tune recognition worse. Results are discussed in the context of implicit memory for nonsemantic materials and the possible differences in timbre and tempo in musical representations.

  20. Whorfian effects on colour memory are not reliable.

    Science.gov (United States)

    Wright, Oliver; Davies, Ian R L; Franklin, Anna

    2015-01-01

    The Whorfian hypothesis suggests that differences between languages cause differences in cognitive processes. Support for this idea comes from studies that find that patterns of colour memory errors made by speakers of different languages align with differences in colour lexicons. The current study provides a large-scale investigation of the relationship between colour language and colour memory, adopting a cross-linguistic and developmental approach. Colour memory on a delayed matching-to-sample (XAB) task was investigated in 2 language groups with differing colour lexicons, for 3 developmental stages and 2 regions of colour space. Analyses used a Bayesian technique to provide simultaneous assessment of two competing hypotheses (H1-Whorfian effect present, H0-Whorfian effect absent). Results of the analyses consistently favoured H0. The findings suggest that Whorfian effects on colour memory are not reliable and that the importance of such effects should not be overestimated.

  1. Effects of methylphenidate on memory functions of adults with ADHD

    NARCIS (Netherlands)

    Fuermaier, Anselm B M; Tucha, Lara; Koerts, Janneke; Weisbrod, Matthias; Lange, Klaus W; Aschenbrenner, Steffen; Tucha, Oliver

    2017-01-01

    Neuropsychological research on adults with attention deficit hyperactivity disorder (ADHD) revealed considerable impairments in memory functions related to executive control. However, only limited evidence exists supporting the effects of pharmacological treatment using methylphenidate (MPH) on

  2. Effects of Divided Attention at Retrieval on Conceptual Implicit Memory.

    Science.gov (United States)

    Prull, Matthew W; Lawless, Courtney; Marshall, Helen M; Sherman, Annabella T K

    2016-01-01

    This study investigated whether conceptual implicit memory is sensitive to process-specific interference at the time of retrieval. Participants performed the implicit memory test of category exemplar generation (CEG; Experiments 1 and 3), or the matched explicit memory test of category-cued recall (Experiment 2), both of which are conceptually driven memory tasks, under one of two divided attention (DA) conditions in which participants simultaneously performed a distracting task. The distracting task was either syllable judgments (dissimilar processes), or semantic judgments (similar processes) on unrelated words. Compared to full attention (FA) in which no distracting task was performed, DA had no effect on CEG priming overall, but reduced category-cued recall similarly regardless of distractor task. Analyses of distractor task performance also revealed differences between implicit and explicit memory retrieval. The evidence suggests that, whereas explicit memory retrieval requires attentional resources and is disrupted by semantic and phonological distracting tasks, conceptual implicit memory is automatic and unaffected even when distractor and memory tasks involve similar processes.

  3. Effects of Divided Attention at Retrieval on Conceptual Implicit Memory

    Directory of Open Access Journals (Sweden)

    Matthew W. Prull

    2016-01-01

    Full Text Available This study investigated whether conceptual implicit memory is sensitive to process-specific interference at the time of retrieval. Participants performed the implicit memory test of category exemplar generation (Experiments 1 and 3, or the matched explicit memory test of category-cued recall (Experiment 2, both of which are conceptually-driven memory tasks, under one of two divided attention (DA conditions in which participants simultaneously performed a distracting task. The distracting task was either syllable judgments (dissimilar processes, or semantic judgments (similar processes on unrelated words. Compared to full attention (FA in which no distracting task was performed, DA had no effect on category exemplar generation priming overall, but reduced category-cued recall similarly regardless of distractor task. Analyses of distractor task performance also revealed differences between implicit and explicit memory retrieval. The evidence suggests that, whereas explicit memory retrieval requires attentional resources and is disrupted by semantic and phonological distracting tasks, conceptual implicit memory is automatic and unaffected even when distractor and memory tasks involve similar processes.

  4. Memory Effects on Movement Behavior in Animal Foraging.

    Science.gov (United States)

    Bracis, Chloe; Gurarie, Eliezer; Van Moorter, Bram; Goodwin, R Andrew

    2015-01-01

    An individual's choices are shaped by its experience, a fundamental property of behavior important to understanding complex processes. Learning and memory are observed across many taxa and can drive behaviors, including foraging behavior. To explore the conditions under which memory provides an advantage, we present a continuous-space, continuous-time model of animal movement that incorporates learning and memory. Using simulation models, we evaluate the benefit memory provides across several types of landscapes with variable-quality resources and compare the memory model within a nested hierarchy of simpler models (behavioral switching and random walk). We find that memory almost always leads to improved foraging success, but that this effect is most marked in landscapes containing sparse, contiguous patches of high-value resources that regenerate relatively fast and are located in an otherwise devoid landscape. In these cases, there is a large payoff for finding a resource patch, due to size, value, or locational difficulty. While memory-informed search is difficult to differentiate from other factors using solely movement data, our results suggest that disproportionate spatial use of higher value areas, higher consumption rates, and consumption variability all point to memory influencing the movement direction of animals in certain ecosystems.

  5. Memory Effects on Movement Behavior in Animal Foraging

    Science.gov (United States)

    Bracis, Chloe; Gurarie, Eliezer; Van Moorter, Bram; Goodwin, R. Andrew

    2015-01-01

    An individual’s choices are shaped by its experience, a fundamental property of behavior important to understanding complex processes. Learning and memory are observed across many taxa and can drive behaviors, including foraging behavior. To explore the conditions under which memory provides an advantage, we present a continuous-space, continuous-time model of animal movement that incorporates learning and memory. Using simulation models, we evaluate the benefit memory provides across several types of landscapes with variable-quality resources and compare the memory model within a nested hierarchy of simpler models (behavioral switching and random walk). We find that memory almost always leads to improved foraging success, but that this effect is most marked in landscapes containing sparse, contiguous patches of high-value resources that regenerate relatively fast and are located in an otherwise devoid landscape. In these cases, there is a large payoff for finding a resource patch, due to size, value, or locational difficulty. While memory-informed search is difficult to differentiate from other factors using solely movement data, our results suggest that disproportionate spatial use of higher value areas, higher consumption rates, and consumption variability all point to memory influencing the movement direction of animals in certain ecosystems. PMID:26288228

  6. Working memory overload: fronto-limbic interactions and effects on subsequent working memory function.

    Science.gov (United States)

    Yun, Richard J; Krystal, John H; Mathalon, Daniel H

    2010-03-01

    The human working memory system provides an experimentally useful model for examination of neural overload effects on subsequent functioning of the overloaded system. This study employed functional magnetic resonance imaging in conjunction with a parametric working memory task to characterize the behavioral and neural effects of cognitive overload on subsequent cognitive performance, with particular attention to cognitive-limbic interactions. Overloading the working memory system was associated with varying degrees of subsequent decline in performance accuracy and reduced activation of brain regions central to both task performance and suppression of negative affect. The degree of performance decline was independently predicted by three separate factors operating during the overload condition: the degree of task failure, the degree of amygdala activation, and the degree of inverse coupling between the amygdala and dorsolateral prefrontal cortex. These findings suggest that vulnerability to overload effects in cognitive functioning may be mediated by reduced amygdala suppression and subsequent amygdala-prefrontal interaction.

  7. The effects of drumming on working memory in older adults.

    Science.gov (United States)

    Degé, Franziska; Kerkovius, Katharina

    2018-05-04

    Our study investigated the effect of a music training program on working memory (verbal memory, visual memory, and as a part of central executive processing working memory) in older adults. The experimental group was musically trained (drumming and singing), whereas one control group received a literature training program and a second control group was untrained. We randomly assigned 24 participants (all females; M = 77 years and 3 months) to the music group, the literature group, and the untrained group. The training groups were trained for 15 weeks. The three groups did not differ significantly in age, socioeconomic status, music education, musical aptitude, cognitive abilities, or depressive symptoms. We did not find differences in the music group in central executive function. However, we found a potential effect of music training on verbal memory and an impact of music training on visual memory. Musically trained participants remembered more words from a word list than both control groups, and they were able to remember more symbol sequences correctly than the control groups. Our findings show a possible effect of music training on verbal and visual memory in older people. © 2018 New York Academy of Sciences.

  8. Coaching positively influences the effects of working memory training on visual working memory as well as mathematical ability

    NARCIS (Netherlands)

    Nelwan, M.; Vissers, C.T.W.M.; Kroesbergen, E.H.

    2018-01-01

    The goal of the present study was to test whether the amount of coaching influenced the results of working memory training on both visual and verbal working memory. Additionally, the effects of the working memory training on the amount of progress after specific training in mathematics were

  9. An additional memory effect in mass spectrometry for BF3

    International Nuclear Information System (INIS)

    Hoshino, Kiichi; Satooka, Sakae

    1978-01-01

    It is considered that the memory effect appears in a metallic gas inlet of a mass spectrometer for measurement with samples of BF 3 is classified into two kinds, one is essential memory effect which is caused by an action between the surface of metal and BF 3 , and the other is additional memory effect which is caused by viscous liquid produced by reaction among water, BF 3 and metals. The additional memory effect is caused by stain on the inner surface of the gas inlet. Air is introduced into the sample bottle joint at each time for change of sample bottle. Moisture in the air is adsorbed on inner surfaces of the joint and piping made of metal, and combined with BF 3 which is introduced, and then viscous compound is produced by dissolution of the metal into the compound made from H 2 O and BF 3 . The vapour pressure of the viscous compound is not sufficient low, and so the compound propagates from the sample bottle joint to the whole of the gas inlet at each time of opening and closing of valves of the gas inlet. The coated film of the viscous compound with adsorption and release of Bf 3 is a cause of the additional memory effect. If the stain of the inner surface of the gas inlet grows up, the additional memory effect becomes more intense compared with the essential memory effect, and the measured values are not converged. To remove the additional memory effect, it is desirable to introduce the sample BF 3 after the moisture intruded into the piping by the exchange of sample bottles is removed sufficiently by introduction of F 2 or ClF 3 . (auth.)

  10. Effect of background music on auditory-verbal memory performance

    OpenAIRE

    Sona Matloubi; Ali Mohammadzadeh; Zahra Jafari; Alireza Akbarzade Baghban

    2014-01-01

    Background and Aim: Music exists in all cultures; many scientists are seeking to understand how music effects cognitive development such as comprehension, memory, and reading skills. More recently, a considerable number of neuroscience studies on music have been developed. This study aimed to investigate the effects of null and positive background music in comparison with silence on auditory-verbal memory performance.Methods: Forty young adults (male and female) with normal hearing, aged betw...

  11. Working memory capacity predicts the beneficial effect of selective memory retrieval.

    Science.gov (United States)

    Schlichting, Andreas; Aslan, Alp; Holterman, Christoph; Bäuml, Karl-Heinz T

    2015-01-01

    Selective retrieval of some studied items can both impair and improve recall of the other items. This study examined the role of working memory capacity (WMC) for the two effects of memory retrieval. Participants studied an item list consisting of predefined target and nontarget items. After study of the list, half of the participants performed an imagination task supposed to induce a change in mental context, whereas the other half performed a counting task which does not induce such context change. Following presentation of a second list, memory for the original list's target items was tested, either with or without preceding retrieval of the list's nontarget items. Consistent with previous work, preceding nontarget retrieval impaired target recall in the absence of the context change, but improved target recall in its presence. In particular, there was a positive relationship between WMC and the beneficial, but not the detrimental effect of memory retrieval. On the basis of the view that the beneficial effect of memory retrieval reflects context-reactivation processes, the results indicate that individuals with higher WMC are better able to capitalise on retrieval-induced context reactivation than individuals with lower WMC.

  12. Stress and Memory: Behavioral Effects and Neurobiological Mechanisms

    Directory of Open Access Journals (Sweden)

    M. Teresa Pinelo-Nava

    2007-04-01

    Full Text Available Stress is a potent modulator of learning and memory processes. Although there have been a few attempts in the literature to explain the diversity of effects (including facilitating, impairing, and lack of effects described for the impact of stress on memory function according to single classification criterion, they have proved insufficient to explain the whole complexity of effects. Here, we review the literature in the field of stress and memory interactions according to five selected classifying factors (source of stress, stressor duration, stressor intensity, stressor timing with regard to memory phase, and learning type in an attempt to develop an integrative model to understand how stress affects memory function. Summarizing on those conditions in which there was enough information, we conclude that high stress levels, whether intrinsic (triggered by the cognitive challenge or extrinsic (induced by conditions completely unrelated to the cognitive task, tend to facilitate Pavlovian conditioning (in a linear-asymptotic manner, while being deleterious for spatial/explicit information processing (which with regard to intrinsic stress levels follows an inverted U-shape effect. Moreover, after reviewing the literature, we conclude that all selected factors are essential to develop an integrative model that defines the outcome of stress effects in memory processes. In parallel, we provide a brief review of the main neurobiological mechanisms proposed to account for the different effects of stress in memory function. Glucocorticoids were found as a common mediating mechanism for both the facilitating and impairing actions of stress in different memory processes and phases. Among the brain regions implicated, the hippocampus, amygdala, and prefrontal cortex were highlighted as critical for the mediation of stress effects.

  13. The effect of cannabis use on memory function: an update

    Directory of Open Access Journals (Sweden)

    Schoeler T

    2013-01-01

    Full Text Available Tabea Schoeler, Sagnik BhattacharyyaDepartment of Psychosis Studies, King's College London, Institute of Psychiatry, London, UKAbstract: Investigating the effects of cannabis use on memory function appears challenging. While early observational investigations aimed to elucidate the longer-term effects of cannabis use on memory function in humans, findings remained equivocal and pointed to a pattern of interacting factors impacting on the relationship between cannabis use and memory function, rather than a simple direct effect of cannabis. Only recently, a clearer picture of the chronic and acute effects of cannabis use on memory function has emerged once studies have controlled for potential confounding factors and started to investigate the acute effects of delta-9-tetrahydrocannabinol (Δ9-THC and cannabidiol (CBD, the main ingredients in the extract of the cannabis plant in pharmacological challenge experiments. Relatively consistent findings have been reported regarding the acute impairments induced by a single dose of Δ9-THC on verbal and working memory. It is unclear whether they may persist beyond the intoxication state. In the long-term, these impairments seem particularly likely to manifest and may also persist following abstinence if regular and heavy use of cannabis strains high in Δ9-THC is started at an early age. Although still at an early stage, studies that employed advanced neuroimaging techniques have started to model the neural underpinnings of the effects of cannabis use and implicate a network of functional and morphological alterations that may moderate the effects of cannabis on memory function. Future experimental and epidemiological studies that take into consideration individual differences, particularly previous cannabis history and demographic characteristics, but also the precise mixture of the ingredients of the consumed cannabis are necessary to clarify the magnitude and the mechanisms by which cannabis

  14. Effects of entorhinal cortex lesions on memory in different tasks

    Directory of Open Access Journals (Sweden)

    G.P. Gutierrez-Figueroa

    1997-06-01

    Full Text Available Lesions of the entorhinal cortex produce retrograde memory impairment in both animals and humans. Here we report the effects of bilateral entorhinal cortex lesions caused by the stereotaxic infusion of N-methyl-D-aspartate (NMDA in rats at two different moments, before or after the training session, on memory of different tasks: two-way shuttle avoidance, inhibitory avoidance and habituation to an open field. Pre- or post-training entorhinal cortex lesions caused an impairment of performance in the shuttle avoidance task, which agrees with the previously described role of this area in the processing of memories acquired in successive sessions. In the inhibitory avoidance task, only the post-training lesions had an effect (amnesia. No effect was observed on the open field task. The findings suggest that the role of the entorhinal cortex in memory processing is task-dependent, perhaps related to the complexity of each task

  15. Memory effects in attenuation and amplification quantum processes

    International Nuclear Information System (INIS)

    Lupo, Cosmo; Giovannetti, Vittorio; Mancini, Stefano

    2010-01-01

    With increasing communication rates via quantum channels, memory effects become unavoidable whenever the use rate of the channel is comparable to the typical relaxation time of the channel environment. We introduce a model of a bosonic memory channel, describing correlated noise effects in quantum-optical processes via attenuating or amplifying media. To study such a channel model, we make use of a proper set of collective field variables, which allows us to unravel the memory effects, mapping the n-fold concatenation of the memory channel to a unitarily equivalent, direct product of n single-mode bosonic channels. We hence estimate the channel capacities by relying on known results for the memoryless setting. Our findings show that the model is characterized by two different regimes, in which the cross correlations induced by the noise among different channel uses are either exponentially enhanced or exponentially reduced.

  16. Pharmacological effects of cannabinoids on learning and memory in Lymnaea.

    Science.gov (United States)

    Sunada, Hiroshi; Watanabe, Takayuki; Hatakeyama, Dai; Lee, Sangmin; Forest, Jeremy; Sakakibara, Manabu; Ito, Etsuro; Lukowiak, Ken

    2017-09-01

    Cannabinoids are hypothesized to play an important role in modulating learning and memory formation. Here, we identified mRNAs expressed in Lymnaea stagnalis central nervous system that encode two G-protein-coupled receptors ( Lymnaea CBr-like 1 and 2) that structurally resemble mammalian cannabinoid receptors (CBrs). We found that injection of a mammalian CBr agonist WIN 55,212-2 (WIN 55) into the snail before operant conditioning obstructed learning and memory formation. This effect of WIN 55 injection persisted for at least 4 days following its injection. A similar obstruction of learning and memory occurred when a severe traumatic stimulus was delivered to L. stagnalis In contrast, injection of a mammalian CBr antagonist AM 251 enhanced long-term memory formation in snails and reduced the duration of the effects of the severe traumatic stressor on learning and memory. Neither WIN 55 nor AM 251 altered normal homeostatic aerial respiratory behaviour elicited in hypoxic conditions. Our results suggest that putative cannabinoid receptors mediate stressful stimuli that alter learning and memory formation in Lymnaea This is also the first demonstration that putative CBrs are present in Lymnaea and play a key role in learning and memory formation. © 2017. Published by The Company of Biologists Ltd.

  17. Glucose enhancement of human memory: a comprehensive research review of the glucose memory facilitation effect.

    Science.gov (United States)

    Smith, Michael A; Riby, Leigh M; Eekelen, J Anke M van; Foster, Jonathan K

    2011-01-01

    The brain relies upon glucose as its primary fuel. In recent years, a rich literature has developed from both human and animal studies indicating that increases in circulating blood glucose can facilitate cognitive functioning. This phenomenon has been termed the 'glucose memory facilitation effect'. The purpose of this review is to discuss a number of salient studies which have investigated the influence of glucose ingestion on neurocognitive performance in individuals with (a) compromised neurocognitive capacity, as well as (b) normally functioning individuals (with a focus on research conducted with human participants). The proposed neurocognitive mechanisms purported to underlie the modulatory effect of glucose on neurocognitive performance will also be considered. Many theories have focussed upon the hippocampus, given that this brain region is heavily implicated in learning and memory. Further, it will be suggested that glucose is a possible mechanism underlying the phenomenon that enhanced memory performance is typically observed for emotionally laden stimuli. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. [Effects of false memories on the Concealed Information Test].

    Science.gov (United States)

    Zaitsu, Wataru

    2012-10-01

    The effects of false memories on polygraph examinations with the Concealed Information Test (CIT) were investigated by using the Deese-Roediger-McDermott (DRM) paradigm, which allows participants to evoke false memories. Physiological responses to questions consisting of learned, lure, and unlearned items were measured and recorded. The results indicated that responses to lure questions showed critical responses to questions about learned items. These responses included repression of respiration, an increase in electrodermal activity, and a drop in heart rate. These results suggest that critical response patterns are generated in the peripheral nervous system by true and false memories.

  19. Negative effects of item repetition on source memory

    OpenAIRE

    Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L.; Johnson, Marcia K.

    2012-01-01

    In the present study, we explored how item repetition affects source memory for new item–feature associations (picture–location or picture–color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item re...

  20. Interference and memory capacity effects in memristive systems

    Science.gov (United States)

    Hermiz, John; Chang, Ting; Du, Chao; Lu, Wei

    2013-02-01

    Short-term memory implies the existence of a capacity limit beyond which memory cannot be securely formed and retained. The underlying mechanisms are believed to be two primary factors: decay and interference. Here, we demonstrate through both simulation and experiment that the memory capacity effect can be implemented in a parallel memristor circuit, where decay and interference are achieved by the inherent ion diffusion in the device and the competition for current supply in the circuit, respectively. This study suggests it is possible to emulate high-level biological behaviors with memristor circuits and will stimulate continued studies on memristor-based neuromorphic circuits.

  1. Task-selective memory effects for successfully implemented encoding strategies.

    Science.gov (United States)

    Leshikar, Eric D; Duarte, Audrey; Hertzog, Christopher

    2012-01-01

    Previous behavioral evidence suggests that instructed strategy use benefits associative memory formation in paired associate tasks. Two such effective encoding strategies--visual imagery and sentence generation--facilitate memory through the production of different types of mediators (e.g., mental images and sentences). Neuroimaging evidence suggests that regions of the brain support memory reflecting the mental operations engaged at the time of study. That work, however, has not taken into account self-reported encoding task success (i.e., whether participants successfully generated a mediator). It is unknown, therefore, whether task-selective memory effects specific to each strategy might be found when encoding strategies are successfully implemented. In this experiment, participants studied pairs of abstract nouns under either visual imagery or sentence generation encoding instructions. At the time of study, participants reported their success at generating a mediator. Outside of the scanner, participants further reported the quality of the generated mediator (e.g., images, sentences) for each word pair. We observed task-selective memory effects for visual imagery in the left middle occipital gyrus, the left precuneus, and the lingual gyrus. No such task-selective effects were observed for sentence generation. Intriguingly, activity at the time of study in the left precuneus was modulated by the self-reported quality (vividness) of the generated mental images with greater activity for trials given higher ratings of quality. These data suggest that regions of the brain support memory in accord with the encoding operations engaged at the time of study.

  2. Long-term memory, sleep, and the spacing effect.

    Science.gov (United States)

    Bell, Matthew C; Kawadri, Nader; Simone, Patricia M; Wiseheart, Melody

    2014-01-01

    Many studies have shown that memory is enhanced when study sessions are spaced apart rather than massed. This spacing effect has been shown to have a lasting benefit to long-term memory when the study phase session follows the encoding session by 24 hours. Using a spacing paradigm we examined the impact of sleep and spacing gaps on long-term declarative memory for Swahili-English word pairs by including four spacing delay gaps (massed, 12 hours same-day, 12 hours overnight, and 24 hours). Results showed that a 12-hour spacing gap that includes sleep promotes long-term memory retention similar to the 24-hour gap. The findings support the importance of sleep to the long-term benefit of the spacing effect.

  3. False memory ≠ false memory: DRM errors are unrelated to the misinformation effect.

    Directory of Open Access Journals (Sweden)

    James Ost

    Full Text Available The DRM method has proved to be a popular and powerful, if controversial, way to study 'false memories'. One reason for the controversy is that the extent to which the DRM effect generalises to other kinds of memory error has been neither satisfactorily established nor subject to much empirical attention. In the present paper we contribute data to this ongoing debate. One hundred and twenty participants took part in a standard misinformation effect experiment, in which they watched some CCTV footage, were exposed to misleading post-event information about events depicted in the footage, and then completed free recall and recognition tests. Participants also completed a DRM test as an ostensibly unrelated filler task. Despite obtaining robust misinformation and DRM effects, there were no correlations between a broad range of misinformation and DRM effect measures (mean r  = -.01. This was not due to reliability issues with our measures or a lack of power. Thus DRM 'false memories' and misinformation effect 'false memories' do not appear to be equivalent.

  4. Memory Color Effect Induced by Familiarity of Brand Logos

    OpenAIRE

    Kimura, Atsushi; Wada, Yuji; Masuda, Tomohiro; Goto, Sho-ichi; Tsuzuki, Daisuke; Hibino, Haruo; Cai, Dongsheng; Dan, Ippeita

    2013-01-01

    Background When people are asked to adjust the color of familiar objects such as fruits until they appear achromatic, the subjective gray points of the objects are shifted away from the physical gray points in a direction opposite to the memory color (memory color effect). It is still unclear whether the discrepancy between memorized and actual colors of objects is dependent on the familiarity of the objects. Here, we conducted two experiments in order to examine the relationship between the ...

  5. Low-level lead exposure effects on spatial reference memory and working memory in rats

    Institute of Scientific and Technical Information of China (English)

    Xinhua Yang; Ping Zhou; Yonghui Li

    2009-01-01

    BACKGROUND: Studies have demonstrated that lead exposure can result in cognitive dysfunction and behavior disorders. However, lead exposure impairments vary under different experimental conditions.OBJECTIVE: To detect changes in spatial learning and memory following low-level lead exposure in rats, in Morris water maze test under the same experimental condition used to analyze lead exposure effects on various memory types and learning processes.DESIGN AND SETTING: The experiment was conducted at the Animal Laboratory, Institute of Psychology, Chinese Academy of Science between February 2005 and March 2006. One-way analysis of variance (ANOVA) and behavioral observations were performed.MATERIALS: Sixteen male, healthy, adult, Sprague Dawley rats were randomized into normal control and lead exposure groups (n = 8).METHODS: Rats in the normal control group were fed distilled water, and those in the lead exposure group were fed 250 mL of 0.05% lead acetate once per day. At day 28, all rats performed the Morris water maze test, consisting of four phases: space navigation, probe test, working memory test, and visual cue test.MAIN OUTCOME MEASURES: Place navigation in the Morris water maze was used to evaluate spatial learning and memory, probe trials for spatial reference memory, working memory test for spatial working memory, and visual cue test for non-spatial cognitive function. Perkin-Elmer Model 300 Atomic Absorption Spectrometer was utilized to determine blood lead levels in rats.RESULTS: (1) In the working memory test, the time to reach the platform remained unchanged between the control and lead exposure groups (F(1,1) = 0.007, P = 0.935). A visible decrease in escape latencies was observed in each group (P = 0.028). However, there was no significant difference between the two groups (F(1,1) = 1.869, P = 0.193). The working memory probe test demonstrated no change between the two groups in the time spent in the target quadrant during the working memory probe test

  6. The sky pattern of the linearized gravitational memory effect

    International Nuclear Information System (INIS)

    Mädler, Thomas; Winicour, Jeffrey

    2016-01-01

    The gravitational memory effect leads to a net displacement in the relative positions of test particles. This memory is related to the change in the strain of the gravitational radiation field between infinite past and infinite future retarded times. There are three known sources of the memory effect: (i) the loss of energy to future null infinity by massless fields or particles, (ii) the ejection of massive particles to infinity from a bound system and (iii) homogeneous, source-free gravitational waves. In the context of linearized theory, we show that asymptotic conditions controlling these known sources of the gravitational memory effect rule out any other possible sources with physically reasonable stress–energy tensors. Except for the source-free gravitational waves, the two other known sources produce gravitational memory with E -mode radiation strain, characterized by a certain curl-free sky pattern of their polarization. Thus our results show that the only known source of B -mode gravitational memory is of primordial origin, corresponding in the linearized theory to a homogeneous wave entering from past null infinity. (paper)

  7. The emotional carryover effect in memory for words.

    Science.gov (United States)

    Schmidt, Stephen R; Schmidt, Constance R

    2016-08-01

    Emotional material rarely occurs in isolation; rather it is experienced in the spatial and temporal proximity of less emotional items. Some previous researchers have found that emotional stimuli impair memory for surrounding information, whereas others have reported evidence for memory facilitation. Researchers have not determined which types of emotional items or memory tests produce effects that carry over to surrounding items. Six experiments are reported that measured carryover from emotional words varying in arousal to temporally adjacent neutral words. Taboo, non-taboo emotional, and neutral words were compared using different stimulus onset asynchronies (SOAs), recognition and recall tests, and intentional and incidental memory instructions. Strong emotional memory effects were obtained in all six experiments. However, emotional items influenced memory for temporally adjacent words under limited conditions. Words following taboo words were more poorly remembered than words following neutral words when relatively short SOAs were employed. Words preceding taboo words were affected only when recall tests and relatively short retention intervals were used. These results suggest that increased attention to the emotional items sometimes produces emotional carryover effects; however, retrieval processes also contribute to retrograde amnesia and may extend the conditions under which anterograde amnesia is observed.

  8. Memory Effects in the Two-Level Model for Glasses

    Science.gov (United States)

    Aquino, Gerardo; Allahverdyan, Armen; Nieuwenhuizen, Theo M.

    2008-07-01

    We study an ensemble of two-level systems interacting with a thermal bath. This is a well-known model for glasses. The origin of memory effects in this model is a quasistationary but nonequilibrium state of a single two-level system, which is realized due to a finite-rate cooling and slow thermally activated relaxation. We show that single-particle memory effects, such as negativity of the specific heat under reheating, vanish for a sufficiently disordered ensemble. In contrast, a disordered ensemble displays a collective memory effect [similar to the Kovacs effect], where nonequilibrium features of the ensemble are monitored via a macroscopic observable. An experimental realization of the effect can be used to further assess the consistency of the model.

  9. Coaching positively influences the effects of working memory training on visual working memory as well as mathematical ability.

    Science.gov (United States)

    Nelwan, Michel; Vissers, Constance; Kroesbergen, Evelyn H

    2018-05-01

    The goal of the present study was to test whether the amount of coaching influenced the results of working memory training on both visual and verbal working memory. Additionally, the effects of the working memory training on the amount of progress after specific training in mathematics were evaluated. In this study, 23 children between 9 and 12 years of age with both attentional and mathematical difficulties participated in a working memory training program with a high amount of coaching, while another 25 children received no working memory training. Results of these groups were compared to 21 children who completed the training with a lower amount of coaching. The quality of working memory, as well as mathematic skills, were measured three times using untrained transfer tasks. Bayesian statistics were used to test informative hypotheses. After receiving working memory training, the highly coached group performed better than the group that received less coaching on visual working memory and mathematics, but not on verbal working memory. The highly coached group retained their advantage in mathematics, even though the effect on visual working memory decreased. However, no added effect of working memory training was found on the learning curve during mathematical training. Moreover, the less-coached group was outperformed by the group that did not receive working memory training, both in visual working memory and mathematics. These results suggest that motivation and proper coaching might be crucial for ensuring compliance and effects of working memory training, and that far transfer might be possible. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Effects of tunnel oxide process on SONOS flash memory characteristics

    International Nuclear Information System (INIS)

    Li, Dong Hua; Park, Il Han; Yun, Jang-Gn; Park, Byung-Gook

    2010-01-01

    In this paper, various process conditions of tunnel oxides are applied in SONOS flash memory to investigate their effects on charge transport during the program/erase operations. We focus the key point of analysis on Fermi-level (E F ) variation at the interface of silicon substrate and tunnel oxide. The Si-O chemical bonding information which describes the interface oxidation states at the Si/SiO 2 is obtained by the core-level X-ray photoelectron spectroscopy (XPS). Moreover, relative E F position is determined by measuring the Si 2p energy shift from XPS spectrums. Experimental results from memory characteristic measurement show that MTO tunnel oxide structure exhibits faster erase speed, and larger memory window during P/E cycle compared to FTO and RTO tunnel oxide structures. Finally, we examine long-term charge retention characteristic and find that the memory windows of all the capacitors remain wider than 2 V after 10 5 s.

  11. Marijuana effects on long-term memory assessment and retrieval.

    Science.gov (United States)

    Darley, C F; Tinklenberg, J R; Roth, W T; Vernon, S; Kopell, B S

    1977-05-09

    The ability of 16 college-educated male subjects to recall from long-term memory a series of common facts was tested during intoxication with marijuana extract calibrated to 0.3 mg/kg delta-9-tetrahydrocannabinol and during placebo conditions. The subjects' ability to assess their memory capabilities was then determined by measuring how certain they were about the accuracy of their recall performance and by having them predict their performance on a subsequent recognition test involving the same recall items. Marijuana had no effect on recall or recognition performance. These results do not support the view that marijuana provides access to facts in long-term storage which are inaccessible during non-intoxication. During both marijuana and placebo conditions, subjects could accurately predict their recognition memory performance. Hence, marijuana did not alter the subjects' ability to accurately assess what information resides in long-term memory even though they did not have complete access to that information.

  12. A facilitative effect of negative affective valence on working memory.

    Science.gov (United States)

    Gotoh, Fumiko; Kikuchi, Tadashi; Olofsson, Ulrich

    2010-06-01

    Previous studies have shown that negatively valenced information impaired working memory performance due to an attention-capturing effect. The present study examined whether negative valence could also facilitate working memory. Affective words (negative, neutral, positive) were used as retro-cues in a working memory task that required participants to remember colors at different spatial locations on a computer screen. Following the cue, a target detection task was used to either shift attention to a different location or keep attention at the same location as the retro-cue. Finally, participants were required to discriminate the cued color from a set of distractors. It was found that negative cues yielded shorter response times (RTs) in the attention-shift condition and longer RTs in the attention-stay condition, compared with neutral and positive cues. The results suggest that negative affective valence may enhance working memory performance (RTs), provided that attention can be disengaged.

  13. Control of crack pattern using memory effect of paste

    International Nuclear Information System (INIS)

    Nakahara, Akio; Shinohara, Yuu; Matsuo, Yousuke

    2011-01-01

    A densely packed colloidal suspension, called as a paste, remembers the direction of external mechanical fields, such as flow and vibration. When the pastes are dried, memories in pastes are visualized as macroscopically anisotropic crack patterns, such as lamellar, radial, ring and spiral. Here, we experimentally investigate how pastes remember such experiences by using paste with different size distribution of colloidal particles. We find that a paste with smaller particles have a better memory, in the sense it remembers external mechanical fields at smaller solid volume fraction, which implies that interparticle forces between colloidal particles play an important role in memory effects, causing a quantitative change in the phase diagram for the same material. This result supports the hypothesis that memories in pastes are maintained as microscopically anisotropic network structure of colloidal particles, connected via interparticle forces between colloidal particles, such as van der Waals interaction.

  14. Memory

    OpenAIRE

    Wager, Nadia

    2017-01-01

    This chapter will explore a response to traumatic victimisation which has divided the opinions of psychologists at an exponential rate. We will be examining amnesia for memories of childhood sexual abuse and the potential to recover these memories in adulthood. Whilst this phenomenon is generally accepted in clinical circles, it is seen as highly contentious amongst research psychologists, particularly experimental cognitive psychologists. The chapter will begin with a real case study of a wo...

  15. Effects of modality and repetition in a continuous recognition memory task: Repetition has no effect on auditory recognition memory.

    Science.gov (United States)

    Amir Kassim, Azlina; Rehman, Rehan; Price, Jessica M

    2018-04-01

    Previous research has shown that auditory recognition memory is poorer compared to visual and cross-modal (visual and auditory) recognition memory. The effect of repetition on memory has been robust in showing improved performance. It is not clear, however, how auditory recognition memory compares to visual and cross-modal recognition memory following repetition. Participants performed a recognition memory task, making old/new discriminations to new stimuli, stimuli repeated for the first time after 4-7 intervening items (R1), or repeated for the second time after 36-39 intervening items (R2). Depending on the condition, participants were either exposed to visual stimuli (2D line drawings), auditory stimuli (spoken words), or cross-modal stimuli (pairs of images and associated spoken words). Results showed that unlike participants in the visual and cross-modal conditions, participants in the auditory recognition did not show improvements in performance on R2 trials compared to R1 trials. These findings have implications for pedagogical techniques in education, as well as for interventions and exercises aimed at boosting memory performance. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. The Modality-Match Effect in Recognition Memory

    Science.gov (United States)

    Mulligan, Neil W.; Osborn, Katherine

    2009-01-01

    The modality-match effect in recognition refers to superior memory for words presented in the same modality at study and test. Prior research on this effect is ambiguous and inconsistent. The present study demonstrates that the modality-match effect is found when modality is rendered salient at either encoding or retrieval. Specifically, in…

  17. Effect of water table dynamics on land surface hydrologic memory

    Science.gov (United States)

    Lo, Min-Hui; Famiglietti, James S.

    2010-11-01

    The representation of groundwater dynamics in land surface models has received considerable attention in recent years. Most studies have found that soil moisture increases after adding a groundwater component because of the additional supply of water to the root zone. However, the effect of groundwater on land surface hydrologic memory (persistence) has not been explored thoroughly. In this study we investigate the effect of water table dynamics on National Center for Atmospheric Research Community Land Model hydrologic simulations in terms of land surface hydrologic memory. Unlike soil water or evapotranspiration, results show that land surface hydrologic memory does not always increase after adding a groundwater component. In regions where the water table level is intermediate, land surface hydrologic memory can even decrease, which occurs when soil moisture and capillary rise from groundwater are not in phase with each other. Further, we explore the hypothesis that in addition to atmospheric forcing, groundwater variations may also play an important role in affecting land surface hydrologic memory. Analyses show that feedbacks of groundwater on land surface hydrologic memory can be positive, negative, or neutral, depending on water table dynamics. In regions where the water table is shallow, the damping process of soil moisture variations by groundwater is not significant, and soil moisture variations are mostly controlled by random noise from atmospheric forcing. In contrast, in regions where the water table is very deep, capillary fluxes from groundwater are small, having limited potential to affect soil moisture variations. Therefore, a positive feedback of groundwater to land surface hydrologic memory is observed in a transition zone between deep and shallow water tables, where capillary fluxes act as a buffer by reducing high-frequency soil moisture variations resulting in longer land surface hydrologic memory.

  18. The effect of rotational viscosity on the memory effect in ferroelectric liquid crystal

    International Nuclear Information System (INIS)

    Kaur, S.; Thakur, A.K.; Chauhan, R.; Bawa, S.S.; Biradar, A.M.

    2004-01-01

    Memory effect in deformed helix ferroelectric liquid crystal (DHFLC) is not a new phenomenon. Although it was reported 12 years ago yet its exact physical behavior is not explained. It has been thought by various researchers all over the world that it might be a transient memory effect. In the present study, it has been observed and predicted that memory effect is of long duration and shows remarkable dependencies on the voltage and frequency of the driving electrical pulse, which is entirely different from the memory effect in surface-stabilized ferroelectric liquid crystal (SSFLC). The memory effect in SSFLC is primarily due to surface effect but in DHFLC, its ultra-short pitch plays a dominant role. So, it has been observed that the memory effect in DHFLC is due to its high viscosity and inter/intra layer dipolar interactions

  19. Memory effect versus exchange bias for maghemite nanoparticles

    International Nuclear Information System (INIS)

    Nadeem, K.; Krenn, H.; Szabó, D.V.

    2015-01-01

    We studied the temperature dependence of memory and exchange bias effects and their dependence on each other in maghemite (γ-Fe 2 O 3 ) nanoparticles by using magnetization studies. Memory effect in zero field cooled process in nanoparticles is a fingerprint of spin-glass behavior which can be due to i) surface disordered spins (surface spin-glass) and/or ii) randomly frozen and interacting nanoparticles core spins (super spin-glass). Temperature region (25–70 K) for measurements has been chosen just below the average blocking temperature (T B =75 K) of the nanoparticles. Memory effect (ME) shows a non-monotonous behavior with temperature. It shows a decreasing trend with decreasing temperature and nearly vanishes below 30 K. However it also decreased again near the blocking temperature of the nanoparticles e.g., 70 K. Exchange bias (EB) in these nanoparticles arises due to core/shell interface interactions. The EB increases sharply below 30 K due to increase in core/shell interactions, while ME starts vanishing below 30 K. We conclude that the core/shell interface interactions or EB have not enhanced the ME but may reduce it in these nanoparticles. - Highlights: • We studied the T-dependent memory and exchange bias (EB) effects in maghemite nanoparticles. • EB causes spin-canting at the core/shell interface which may reduces the memory effect (ME). • Interface interactions does not increase the ME in these nanoparticles

  20. Memory effect versus exchange bias for maghemite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Nadeem, K., E-mail: kashif.nadeem@iiu.edu.pk [Materials Research Laboratory, Department of Physics, International Islamic University, Islamabad (Pakistan); Krenn, H. [Institute of Physics, Karl-Franzens University Graz, Universitätsplatz 5, A-8010 Graz (Austria); Szabó, D.V. [Karlsruhe Institute of Technology, Institute for Applied Materials, 76344 Eggenstein-Leopoldshafen (Germany)

    2015-11-01

    We studied the temperature dependence of memory and exchange bias effects and their dependence on each other in maghemite (γ-Fe{sub 2}O{sub 3}) nanoparticles by using magnetization studies. Memory effect in zero field cooled process in nanoparticles is a fingerprint of spin-glass behavior which can be due to i) surface disordered spins (surface spin-glass) and/or ii) randomly frozen and interacting nanoparticles core spins (super spin-glass). Temperature region (25–70 K) for measurements has been chosen just below the average blocking temperature (T{sub B}=75 K) of the nanoparticles. Memory effect (ME) shows a non-monotonous behavior with temperature. It shows a decreasing trend with decreasing temperature and nearly vanishes below 30 K. However it also decreased again near the blocking temperature of the nanoparticles e.g., 70 K. Exchange bias (EB) in these nanoparticles arises due to core/shell interface interactions. The EB increases sharply below 30 K due to increase in core/shell interactions, while ME starts vanishing below 30 K. We conclude that the core/shell interface interactions or EB have not enhanced the ME but may reduce it in these nanoparticles. - Highlights: • We studied the T-dependent memory and exchange bias (EB) effects in maghemite nanoparticles. • EB causes spin-canting at the core/shell interface which may reduces the memory effect (ME). • Interface interactions does not increase the ME in these nanoparticles.

  1. Memory effects in single-molecule spectroscopy

    International Nuclear Information System (INIS)

    Schmitt, Daniel T.; Schulz, Michael; Reineker, Peter

    2007-01-01

    From the time series of LH2 optical single-molecule fluorescence excitation spectra of Rhodospirillum molischianum the memory function of the Mori-Zwanzig equation for the optical intensity is derived numerically. We show that the time dependence of the excited states is determined by at least three different non-Markovian stochastic processes with decay constants for the Mori-Zwanzig kernel on the order of 1-5min -1 . We suggest that this decay stems from the conformational motion of the protein scaffold of LH2

  2. Memory for tonal pitches: a music-length effect hypothesis.

    Science.gov (United States)

    Akiva-Kabiri, Lilach; Vecchi, Tomaso; Granot, Roni; Basso, Demis; Schön, Daniele

    2009-07-01

    One of the most studied effects of verbal working memory (WM) is the influence of the length of the words that compose the list to be remembered. This work aims to investigate the nature of musical WM by replicating the word length effect in the musical domain. Length and rate of presentation were manipulated in a recognition task of tone sequences. Results showed significant effects for both factors (length and presentation rate) as well as their interaction, suggesting the existence of different strategies (e.g., chunking and rehearsal) for the immediate memory of musical information, depending upon the length of the sequences.

  3. Giant Kovacs-Like Memory Effect for Active Particles

    Science.gov (United States)

    Kürsten, Rüdiger; Sushkov, Vladimir; Ihle, Thomas

    2017-11-01

    Dynamical properties of self-propelled particles obeying a bounded confidence rule are investigated by means of kinetic theory and agent-based simulations. While memory effects are observed in disordered systems, we show that they also occur in active matter systems. In particular, we find that the system exhibits a giant Kovacs-like memory effect that is much larger than predicted by a generic linear theory. Based on a separation of time scales we develop a nonlinear theory to explain this effect. We apply this theory to driven granular gases and propose further applications to spin glasses.

  4. Magnetocaloric effect in Heusler shape-memory alloys

    International Nuclear Information System (INIS)

    Planes, A.; Manosa, Ll.; Moya, X.; Krenke, T.; Acet, M.; Wassermann, E.F.

    2007-01-01

    We present a comparative study of the magnetocaloric properties of Ni-Mn-X Heusler shape-memory alloys with X=Ga, Sn and In. In these materials, the magnetocaloric effect is a consequence of the magnetostructural coupling that enables the magnetic shape-memory properties. We show that inverse magnetocaloric effects can occur in these materials. The origin of this anomalous behavior is different in stoichiometric Ni 2 MnGa and in Ni-Mn-Sn/In. In the former case it is related to the strong uniaxial magnetic anisotropy of the martensitic phase, while in the later it is an intrinsic effect associated with an incipient antiferromagnetism

  5. Evidence against memorial facilitation and context-dependent memory effects through the chewing of gum

    OpenAIRE

    Johnson, A.J.; Miles, C.

    2007-01-01

    The experiment examined the prediction that chewing gum at learning and/or recall facilitated subsequent word recall. Chewing gum at learning significantly impaired recall, indicating that the chewing of gum has a detrimental impact upon initial word encoding. In addition, a context-dependent memory effect was reported for those participants who both learned and recalled in the absence of gum, however a context dependent effect was not found with chewing gum. The findings contradict previous ...

  6. Evidence against memorial facilitation and context-dependent memory effects through the chewing of gum.

    Science.gov (United States)

    Johnson, Andrew J; Miles, Christopher

    2007-05-01

    The experiment examined the prediction that chewing gum at learning and/or recall facilitated subsequent word recall. Chewing gum at learning significantly impaired recall, indicating that the chewing of gum has a detrimental impact upon initial word encoding. In addition, a context-dependent memory effect was reported for those participants who both learned and recalled in the absence of gum; however, a context-dependent effect was not found with chewing gum. The findings contradict previous research.

  7. Significantly enhanced memory effect in metallic glass by multistep training

    Science.gov (United States)

    Li, M. X.; Luo, P.; Sun, Y. T.; Wen, P.; Bai, H. Y.; Liu, Y. H.; Wang, W. H.

    2017-11-01

    The state of metastable equilibrium glass can carry an imprint of the past and exhibit memory effect. As a hallmark of glassy dynamics, memory effect can affect glassy behavior as it evolves further upon time. Even though the physical picture of the memory effect has been well studied, it is unclear whether a glass can recall as many pieces of information as possible, and if so, how the glass will accordingly behave. We report that by fractionizing temperature interval, inserting multistep aging protocols, and optimizing the time of each temperature step, i.e., by imposing a multistep "training" on a prototypical P d40N i10C u30P20 metallic glass, the memory of the trained glass can be significantly strengthened, marked by a pronounced augment in potential energy. These findings provide a new guide for regulating the energy state of glass by enhancing the nonequilibrium behaviors of the memory effect and offer an opportunity to develop a clearer physical picture of glassy dynamics.

  8. Sleep and environmental context: interactive effects for memory.

    Science.gov (United States)

    Cairney, Scott A; Durrant, Simon J; Musgrove, Hazel; Lewis, Penelope A

    2011-09-01

    Sleep after learning is often beneficial for memory. Reinstating an environmental context that was present at learning during subsequent retrieval also leads to superior declarative memory performance. This study examined how post-learning sleep, relative to wakefulness, impacts upon context-dependent memory effects. Thirty-two participants encoded word lists in each of two rooms (contexts), which were different in terms of size, odour and background music. Immediately after learning and following a night of sleep or a day of wakefulness, memory for all previously studied words was tested using a category-cued recall task in room one or two alone. Accordingly, a comparison could be made between words retrieved in an environmental context which was the same as, or different to, that of the learning phase. Memory performance was assessed by the difference between the number of words remembered at immediate and delayed retrieval. A 2 × 2 × 2 mixed ANOVA revealed an interaction between retrieval context (same/different to learning) and retention interval (sleep/wakefulness), which was driven by superior memory after sleep than after wake when learning and retrieval took place in different environmental contexts. Our findings suggest a sleep-related reduction in the extent to which context impacts upon retrieval. As such, these data provide initial support for the possibility that sleep dependent processes may promote a decontextualisation of recently formed declarative representations.

  9. Hearing something emotional influences memory for what was just seen: How arousal amplifies effects of competition in memory consolidation.

    Science.gov (United States)

    Ponzio, Allison; Mather, Mara

    2014-12-01

    Enhanced memory for emotional items often comes at the cost of memory for the background scenes. Because emotional foreground items both induce arousal and attract attention, it is not clear whether the emotion effects are simply the result of shifts in visual attention during encoding or whether arousal has effects beyond simple attention capture. In the current study, participants viewed a series of scenes that each either had a foreground object or did not have one, and then, after each image, heard either an emotionally arousing negative sound or a neutral sound. After a 24-hr delay, they returned for a memory test for the objects and scenes. Postencoding arousal decreased recognition memory of scenes shown behind superimposed objects but not memory of scenes shown alone. These findings support the hypothesis that arousal amplifies the effects of competition between mental representations, influencing memory consolidation of currently active representations.

  10. The effects of acute hypoglycaemia on memory acquisition and recall and prospective memory in type 1 diabetes.

    Science.gov (United States)

    Warren, R E; Zammitt, N N; Deary, I J; Frier, B M

    2007-01-01

    Global memory performance is impaired during acute hypoglycaemia. This study assessed whether moderate hypoglycaemia disrupts learning and recall in isolation, and utilised a novel test of prospective memory which may better reflect the role of memory in daily life than conventional tests. Thirty-six subjects with type 1 diabetes participated, 20 with normal hypoglycaemia awareness (NHA) and 16 with impaired hypoglycaemia awareness (IHA). Each underwent a hypoglycaemic clamp with target blood glucose 2.5 mmol/l. Prior to hypoglycaemia, subjects attempted to memorise instructions for a prospective memory task, and recall was assessed during hypoglycaemia. Subjects then completed the learning and immediate recall stages of three conventional memory tasks (word recall, story recall, visual recall) during hypoglycaemia. Euglycaemia was restored and delayed memory for the conventional tasks was tested. The same procedures were completed in euglycaemic control studies (blood glucose 4.5 mmol/l). Hypoglycaemia impaired performance significantly on the prospective memory task (p = 0.004). Hypoglycaemia also significantly impaired both immediate and delayed recall for the word and story recall tasks (p visual memory task. The effect of hypoglycaemia did not differ significantly between subjects with NHA and IHA. Impaired performance on the prospective memory task during hypoglycaemia demonstrates that recall is disrupted by hypoglycaemia. Impaired performance on the conventional memory tasks demonstrates that learning is also disrupted by hypoglycaemia. Results of the prospective memory task support the relevance of these findings to the everyday lives of people with diabetes.

  11. The effects of refreshing and elaboration on working memory performance, and their contributions to long-term memory formation.

    Science.gov (United States)

    Bartsch, Lea M; Singmann, Henrik; Oberauer, Klaus

    2018-03-19

    Refreshing and elaboration are cognitive processes assumed to underlie verbal working-memory maintenance and assumed to support long-term memory formation. Whereas refreshing refers to the attentional focussing on representations, elaboration refers to linking representations in working memory into existing semantic networks. We measured the impact of instructed refreshing and elaboration on working and long-term memory separately, and investigated to what extent both processes are distinct in their contributions to working as well as long-term memory. Compared with a no-processing baseline, immediate memory was improved by repeating the items, but not by refreshing them. There was no credible effect of elaboration on working memory, except when items were repeated at the same time. Long-term memory benefited from elaboration, but not from refreshing the words. The results replicate the long-term memory benefit for elaboration, but do not support its beneficial role for working memory. Further, refreshing preserves immediate memory, but does not improve it beyond the level achieved without any processing.

  12. Kinetics of the deformation induced memory effect in polyamide-6

    NARCIS (Netherlands)

    Drongelen, van M.; Stroeks, A.A.M.; Peters, G.W.M.

    2015-01-01

    Nascent polyamide-6 shows a peculiar and irreversible effect; the quiescent crystallization kinetics on cooling are accelerated upon deformation in the melt, even after full relaxation of the melt. This phenomenon, known as the orientation (or better, deformation) induced memory effect of polyamide

  13. The Self-Reference Effect on Memory in Early Childhood

    Science.gov (United States)

    Cunningham, Sheila J.; Brebner, Joanne L.; Quinn, Francis; Turk, David J.

    2014-01-01

    The self-reference effect in memory is the advantage for information encoded about self, relative to other people. The early development of this effect was explored here using a concrete encoding paradigm. Trials comprised presentation of a self- or other-image paired with a concrete object. In Study 1, 4- to 6-year-old children (N = 53) were…

  14. The Effects of Caffeine on Memory for Word Lists.

    Science.gov (United States)

    Erikson, George; And Others

    Research has suggested that behavioral differences may account for the effects of caffeine on information processing. To investigate the effects of caffeine on memory for supraspan word lists, 107 college students (47 males, 60 females), divided into 12 groups by high and low impulsivity scores on the Eysenck Personality Inventory, participated in…

  15. Temporal correlations and structural memory effects in break junction measurements

    DEFF Research Database (Denmark)

    Magyarkuti, A.; Lauritzen, Kasper Primdal; Balogh, Zoltan Imre

    2017-01-01

    that correlations between the opening and subsequent closing traces may indicate structural memory effects in atomic-sized metallic and molecular junctions. Applying these methods on measured and simulated gold metallic contacts as a test system, we show that the surface diffusion induced flattening of the broken......-molecule junctions, we demonstrate pronounced contact memory effects and recovery of the molecule for junctions breaking before atomic chains are formed. However, if chains are pulled the random relaxation of the chain and molecule after rupture prevents opening-closing correlations....

  16. The effect of quantum memory on quantum games

    International Nuclear Information System (INIS)

    Ramzan, M; Nawaz, Ahmad; Toor, A H; Khan, M K

    2008-01-01

    We study quantum games with correlated noise through a generalized quantization scheme. We investigate the effects of memory on quantum games, such as Prisoner's Dilemma, Battle of the Sexes and Chicken, through three prototype quantum-correlated channels. It is shown that the quantum player enjoys an advantage over the classical player for all nine cases considered in this paper for the maximally entangled case. However, the quantum player can also outperform the classical player for subsequent cases that can be noted in the case of the Battle of the Sexes game. It can be seen that the Nash equilibria do not change for all the three games under the effect of memory

  17. A new memory effect (MSD) in fully depleted SOI MOSFETs

    Science.gov (United States)

    Bawedin, M.; Cristoloveanu, S.; Yun, J. G.; Flandre, D.

    2005-09-01

    We demonstrate that the transconductance and drain current of fully depleted MOSFETs can display an interesting time-dependent hysteresis. This new memory effect, called meta-stable dip (MSD), is mainly due to the long carrier generation lifetime in the silicon film. Our parametric analysis shows that the memory window can be adjusted in view of practical applications. Various measurement conditions and devices with different doping, front oxide and silicon film thicknesses are systematically explored. The MSD effect can be generalized to several fully depleted CMOS technologies. The MSD mechanism is discussed and validated by two-dimensional simulations results.

  18. Effects of saccadic bilateral eye movements on episodic and semantic autobiographical memory fluency.

    Science.gov (United States)

    Parker, Andrew; Parkin, Adam; Dagnall, Neil

    2013-01-01

    Performing a sequence of fast saccadic horizontal eye movements has been shown to facilitate performance on a range of cognitive tasks, including the retrieval of episodic memories. One explanation for these effects is based on the hypothesis that saccadic eye movements increase hemispheric interaction, and that such interactions are important for particular types of memory. The aim of the current research was to assess the effect of horizontal saccadic eye movements on the retrieval of both episodic autobiographical memory (event/incident based memory) and semantic autobiographical memory (fact based memory) over recent and more distant time periods. It was found that saccadic eye movements facilitated the retrieval of episodic autobiographical memories (over all time periods) but not semantic autobiographical memories. In addition, eye movements did not enhance the retrieval of non-autobiographical semantic memory. This finding illustrates a dissociation between the episodic and semantic characteristics of personal memory and is considered within the context of hemispheric contributions to episodic memory performance.

  19. Shape memory effect for titanium nickelide semiproducts

    International Nuclear Information System (INIS)

    Chernov, D.B.; Fatkullina, L.P.; Smirnova, Z.I.; Timonin, G.D.; Olejnikova, S.V.

    1978-01-01

    The thermomechanical properties of titanium nickelide semi-finished products obtained by garnissage melting followed by arc remelting have been studied for the purpose of investigating the NiTi ''form memory'' mechanism. The ingots were subjected to stepped pressing to produce rods. Calcined rods were tension tested. Investigation of the elastic and thermomechanical free return after deformation has shown that the share of elastic return increases as the preliminary deformation degree is increased. The return to the original form began at about 150 deg C; at 200 deg C the process rate decreases and at 300 deg C it stops. The degree of form recovery decreases with the increase of preliminary deformation. The return stress versus preliminary deformation degree relationship has a maximum at 11% strain degree. Maximum thermomechanical return stresses are observed at about 300 deg C. It is noted that yield strength decreases with the increasing degree of deformation to which the semi-finished products are subjected

  20. Memory function after stress : the effects of acute stress and cortisol on memory and the inhibition of emotional distraction

    NARCIS (Netherlands)

    Oei, Nicole Yü Lan

    2010-01-01

    The present thesis contains five experimental studies into the effects of stress on memory I healthy males. Hydrocortisone (and propranolol) administration or the induction of social stress are used to heighten cortisol levels, and consequently to study its effects on working memory performance and

  1. Nonvolatile memory effect of tungsten nanocrystals under oxygen plasma treatments

    International Nuclear Information System (INIS)

    Chen, Shih-Cheng; Chang, Ting-Chang; Chen, Wei-Ren; Lo, Yuan-Chun; Wu, Kai-Ting; Sze, S.M.; Chen, Jason; Liao, I.H.; Yeh, Fon-Shan

    2010-01-01

    In this work, an oxygen plasma treatment was used to improve the memory effect of nonvolatile W nanocrystal memory, including memory window, retention and endurance. To investigate the role of the oxygen plasma treatment in charge storage characteristics, the X-ray photon-emission spectra (XPS) were performed to analyze the variation of chemical composition for W nanocrystal embedded oxide both with and without the oxygen plasma treatment. In addition, the transmission electron microscopy (TEM) analyses were also used to identify the microstructure in the thin film and the size and density of W nanocrystals. The device with the oxygen plasma treatment shows a significant improvement of charge storage effect, because the oxygen plasma treatment enhanced the quality of silicon oxide surrounding the W nanocrystals. Therefore, the data retention and endurance characteristics were also improved by the passivation.

  2. Working memory in multilingual children: is there a bilingual effect?

    Science.gov (United States)

    Engel de Abreu, Pascale M J

    2011-07-01

    This research investigates whether early childhood bilingualism affects working memory performance in 6- to 8-year-olds, followed over a longitudinal period of 3 years. The study tests the hypothesis that bilinguals might exhibit more efficient working memory abilities than monolinguals, potentially via the opportunity a bilingual environment provides to train cognitive control by combating interference and intrusions from the non-target language. A total of 44 bilingual and monolingual children, matched on age, sex, and socioeconomic status, completed assessments of working memory (simple span and complex span tasks), fluid intelligence, and language (vocabulary and syntax). The data showed that the monolinguals performed significantly better on the language measures across the years, whereas no language group effect emerged on the working memory and fluid intelligence tasks after verbal abilities were considered. The study suggests that the need to manage several language systems in the bilingual mind has an impact on children's language skills while having little effects on the development of working memory.

  3. Prestimulus subsequent memory effects for auditory and visual events.

    Science.gov (United States)

    Otten, Leun J; Quayle, Angela H; Puvaneswaran, Bhamini

    2010-06-01

    It has been assumed that the effective encoding of information into memory primarily depends on neural activity elicited when an event is initially encountered. Recently, it has been shown that memory formation also relies on neural activity just before an event. The precise role of such activity in memory is currently unknown. Here, we address whether prestimulus activity affects the encoding of auditory and visual events, is set up on a trial-by-trial basis, and varies as a function of the type of recognition judgment an item later receives. Electrical brain activity was recorded from the scalps of 24 healthy young adults while they made semantic judgments on randomly intermixed series of visual and auditory words. Each word was preceded by a cue signaling the modality of the upcoming word. Auditory words were preceded by auditory cues and visual words by visual cues. A recognition memory test with remember/know judgments followed after a delay of about 45 min. As observed previously, a negative-going, frontally distributed modulation just before visual word onset predicted later recollection of the word. Crucially, the same effect was found for auditory words and observed on stay as well as switch trials. These findings emphasize the flexibility and general role of prestimulus activity in memory formation, and support a functional interpretation of the activity in terms of semantic preparation. At least with an unpredictable trial sequence, the activity is set up anew on each trial.

  4. Negative effects of item repetition on source memory.

    Science.gov (United States)

    Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L; Johnson, Marcia K

    2012-08-01

    In the present study, we explored how item repetition affects source memory for new item-feature associations (picture-location or picture-color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item repetition also had a negative effect on source memory when different source dimensions were used in Phases 1 and 2 (Experiment 3) and when participants were explicitly instructed to learn source information in Phase 2 (Experiments 4 and 5). Importantly, when the order between Phases 1 and 2 was reversed, such that item repetition occurred after the encoding of critical item-source combinations, item repetition no longer affected source memory (Experiment 6). Overall, our findings did not support predictions based on item predifferentiation, within-dimension source interference, or general interference from multiple traces of an item. Rather, the findings were consistent with the idea that prior item repetition reduces attention to subsequent presentations of the item, decreasing the likelihood that critical item-source associations will be encoded.

  5. Memories.

    Science.gov (United States)

    Brand, Judith, Ed.

    1998-01-01

    This theme issue of the journal "Exploring" covers the topic of "memories" and describes an exhibition at San Francisco's Exploratorium that ran from May 22, 1998 through January 1999 and that contained over 40 hands-on exhibits, demonstrations, artworks, images, sounds, smells, and tastes that demonstrated and depicted the biological,…

  6. Task-selective memory effects for successfully implemented encoding strategies.

    Directory of Open Access Journals (Sweden)

    Eric D Leshikar

    Full Text Available Previous behavioral evidence suggests that instructed strategy use benefits associative memory formation in paired associate tasks. Two such effective encoding strategies--visual imagery and sentence generation--facilitate memory through the production of different types of mediators (e.g., mental images and sentences. Neuroimaging evidence suggests that regions of the brain support memory reflecting the mental operations engaged at the time of study. That work, however, has not taken into account self-reported encoding task success (i.e., whether participants successfully generated a mediator. It is unknown, therefore, whether task-selective memory effects specific to each strategy might be found when encoding strategies are successfully implemented. In this experiment, participants studied pairs of abstract nouns under either visual imagery or sentence generation encoding instructions. At the time of study, participants reported their success at generating a mediator. Outside of the scanner, participants further reported the quality of the generated mediator (e.g., images, sentences for each word pair. We observed task-selective memory effects for visual imagery in the left middle occipital gyrus, the left precuneus, and the lingual gyrus. No such task-selective effects were observed for sentence generation. Intriguingly, activity at the time of study in the left precuneus was modulated by the self-reported quality (vividness of the generated mental images with greater activity for trials given higher ratings of quality. These data suggest that regions of the brain support memory in accord with the encoding operations engaged at the time of study.

  7. A Bayesian Model of the Memory Colour Effect

    OpenAIRE

    Witzel, Christoph; Olkkonen, Maria; Gegenfurtner, Karl R.

    2018-01-01

    According to the memory colour effect, the colour of a colour-diagnostic object is not perceived independently of the object itself. Instead, it has been shown through an achromatic adjustment method that colour-diagnostic objects still appear slightly in their typical colour, even when they are colourimetrically grey. Bayesian models provide a promising approach to capture the effect of prior knowledge on colour perception and to link these effects to more general effects of cue integration....

  8. A Bayesian model of the memory colour effect.

    OpenAIRE

    Witzel, Christoph; Olkkonen, Maria; Gegenfurtner, Karl R.

    2018-01-01

    According to the memory colour effect, the colour of a colour-diagnostic object is not perceived independently of the object itself. Instead, it has been shown through an achromatic adjustment method that colour-diagnostic objects still appear slightly in their typical colour, even when they are colourimetrically grey. Bayesian models provide a promising approach to capture the effect of prior knowledge on colour perception and to link these effects to more general effects of cue integration....

  9. The effect of divided attention on false memory depends on how memory is tested.

    OpenAIRE

    Dewhurst, Stephen A.; Barry, Christopher; Swannell, Ellen R.; Holmes, Selina J.; Bathurst, Gemma J.

    2007-01-01

    In three experiments, we investigated the effects of divided attention on false memory, using the Deese/Roediger-McDermott (DRM) paradigm. In Experiments 1 and 2, participants studied six DRM lists with full attention and six in one of two divided-attention conditions (random number generation or digit monitoring). Both divided-attention conditions increased false recall of related words (Experiment 1) but reduced false recognition (Experiment 2). These results were confirmed in Experiment 3,...

  10. Beneficial effects of semantic memory support on older adults' episodic memory: Differential patterns of support of item and associative information.

    Science.gov (United States)

    Mohanty, Praggyan Pam; Naveh-Benjamin, Moshe; Ratneshwar, Srinivasan

    2016-02-01

    The effects of two types of semantic memory support-meaningfulness of an item and relatedness between items-in mitigating age-related deficits in item and associative, memory are examined in a marketing context. In Experiment 1, participants studied less (vs. more) meaningful brand logo graphics (pictures) paired with meaningful brand names (words) and later were assessed by item (old/new) and associative (intact/recombined) memory recognition tests. Results showed that meaningfulness of items eliminated age deficits in item memory, while equivalently boosting associative memory for older and younger adults. Experiment 2, in which related and unrelated brand logo graphics and brand name pairs served as stimuli, revealed that relatedness between items eliminated age deficits in associative memory, while improving to the same degree item memory in older and younger adults. Experiment 2 also provided evidence for a probable boundary condition that could reconcile seemingly contradictory extant results. Overall, these experiments provided evidence that although the two types of semantic memory support can improve both item and associative memory in older and younger adults, older adults' memory deficits can be eliminated when the type of support provided is compatible with the type of information required to perform well on the test. (c) 2016 APA, all rights reserved).

  11. Age differences and format effects in working memory.

    Science.gov (United States)

    Foos, Paul W; Goolkasian, Paula

    2010-07-01

    Format effects refer to lower recall of printed words from working memory when compared to spoken words or pictures. These effects have been attributed to an attenuation of attention to printed words. The present experiment compares younger and older adults' recall of three or six items presented as pictures, spoken words, printed words, and alternating case WoRdS. The latter stimuli have been shown to increase attention to printed words and, thus, reduce format effects. The question of interest was whether these stimuli would also reduce format effects for older adults whose working memory capacity has fewer attentional resources to allocate. Results showed that older adults performed as well as younger adults with three items but less well with six and that format effects were reduced for both age groups, but more for young, when alternating case words were used. Other findings regarding executive control of working memory are discussed. The obtained differences support models of reduced capacity in older adult working memory.

  12. Effects of Sleep Deprivation and Aging on Long-Term and Remote Memory in Mice

    Science.gov (United States)

    Vecsey, Christopher G.; Park, Alan J.; Khatib, Nora; Abel, Ted

    2015-01-01

    Sleep deprivation (SD) following hippocampus-dependent learning in young mice impairs memory when tested the following day. Here, we examined the effects of SD on remote memory in both young and aged mice. In young mice, we found that memory is still impaired 1 mo after training. SD also impaired memory in aged mice 1 d after training, but, by a…

  13. Designing of all optical generalized circuit for two-input binary and multi-valued logical operations

    Science.gov (United States)

    Bhowmik, Panchatapa; Roy, Jitendra Nath; Chattopadhyay, Tanay

    2014-11-01

    This paper presents a generalized all optical circuit of two-input logical operation (both binary and multi-valued), using an optical nonlinear material (OPNLM) based switch. The inputs of the logic gates are represented by different polarization states of light. This model is simple, practical and very much useful for future all optical information processing. Proposed scheme can work for different wavelengths and for different materials. The simulation result with the nonlinear material gold nanoparticle embedded in optically transparent matrices alumina (Al2O3) is also presented in the paper.

  14. Emotional stimuli exert parallel effects on attention and memory.

    Science.gov (United States)

    Talmi, Deborah; Ziegler, Marilyne; Hawksworth, Jade; Lalani, Safina; Herman, C Peter; Moscovitch, Morris

    2013-01-01

    Because emotional and neutral stimuli typically differ on non-emotional dimensions, it has been difficult to determine conclusively which factors underlie the ability of emotional stimuli to enhance immediate long-term memory. Here we induced arousal by varying participants' goals, a method that removes many potential confounds between emotional and non-emotional items. Hungry and sated participants encoded food and clothing images under divided attention conditions. Sated participants attended to and recalled food and clothing images equivalently. Hungry participants performed worse on the concurrent tone-discrimination task when they viewed food relative to clothing images, suggesting enhanced attention to food images, and they recalled more food than clothing images. A follow-up regression analysis of the factors predicting memory for individual pictures revealed that food images had parallel effects on attention and memory in hungry participants, so that enhanced attention to food images did not predict their enhanced memory. We suggest that immediate long-term memory for food is enhanced in the hungry state because hunger leads to more distinctive processing of food images rendering them more accessible during retrieval.

  15. The effects of cholesterol on learning and memory.

    Science.gov (United States)

    Schreurs, Bernard G

    2010-07-01

    Cholesterol is vital to normal brain function including learning and memory but that involvement is as complex as the synthesis, metabolism and excretion of cholesterol itself. Dietary cholesterol influences learning tasks from water maze to fear conditioning even though cholesterol does not cross the blood brain barrier. Excess cholesterol has many consequences including peripheral pathology that can signal brain via cholesterol metabolites, pro-inflammatory mediators and antioxidant processes. Manipulations of cholesterol within the central nervous system through genetic, pharmacological, or metabolic means circumvent the blood brain barrier and affect learning and memory but often in animals already otherwise compromised. The human literature is no less complex. Cholesterol reduction using statins improves memory in some cases but not others. There is also controversy over statin use to alleviate memory problems in Alzheimer's disease. Correlations of cholesterol and cognitive function are mixed and association studies find some genetic polymorphisms are related to cognitive function but others are not. In sum, the field is in flux with a number of seemingly contradictory results and many complexities. Nevertheless, understanding cholesterol effects on learning and memory is too important to ignore.

  16. Effects of emotional content on working memory capacity.

    Science.gov (United States)

    Garrison, Katie E; Schmeichel, Brandon J

    2018-02-13

    Emotional events tend to be remembered better than neutral events, but emotional states and stimuli may also interfere with cognitive processes that underlie memory performance. The current study investigated the effects of emotional content on working memory capacity (WMC), which involves both short term storage and executive attention control. We tested competing hypotheses in a preregistered experiment (N = 297). The emotional enhancement hypothesis predicts that emotional stimuli attract attention and additional processing resources relative to neutral stimuli, thereby making it easier to encode and store emotional information in WMC. The emotional impairment hypothesis, by contrast, predicts that emotional stimuli interfere with attention control and the active maintenance of information in working memory. Participants completed a common measure of WMC (the operation span task; Turner, M. L., & Engle, R. W. [1989]. Is working memory capacity task dependent? Journal of Memory and Language, 28, 127-154) that included either emotional or neutral words. Results revealed that WMC was reduced for emotional words relative to neutral words, consistent with the emotional impairment hypothesis.

  17. Neutron irradiation effect on thermomechanical properties of shape memory alloys

    International Nuclear Information System (INIS)

    Abramov, V.Ya.; Ionajtis, R.R.; Kotov, V.V.; Loguntsev, E.N.; Ushakov, V.P.

    1996-01-01

    Alloys of Ti-Ni, Ti-Ni-Pd, Fe-Mn-Si, Mn-Cu-Cr, Mn-Cu, Cu-Al-Mn, Cu-Al-Ni systems are investigated after irradiation in IVV-2M reactor at various temperatures with neutron fluence of 10 19 - 10 20 cm -2 . The degradation of shape memory effect in titanium nickelide base alloys is revealed after irradiation. Mn-Cu and Mn-Cu-Cr alloys show the best results. Trends in shape memory alloy behaviour depending on irradiation temperature are found. A consideration is given to the possibility of using these alloys for components of power reactor control and protection systems [ru

  18. Dynamics of Quantum Entanglement in Reservoir with Memory Effects

    International Nuclear Information System (INIS)

    Hao Xiang; Sha Jinqiao; Sun Jian; Zhu Shiqun

    2012-01-01

    The non-Markovian dynamics of quantum entanglement is studied by the Shabani-Lidar master equation when one of entangled quantum systems is coupled to a local reservoir with memory effects. The completely positive reduced dynamical map can be constructed in the Kraus representation. Quantum entanglement decays more slowly in the non-Markovian environment. The decoherence time for quantum entanglement can be markedly increased with the change of the memory kernel. It is found out that the entanglement sudden death between quantum systems and entanglement sudden birth between the system and reservoir occur at different instants. (general)

  19. Trinary arithmetic and logic unit (TALU) using savart plate and spatial light modulator (SLM) suitable for optical computation in multivalued logic

    Science.gov (United States)

    Ghosh, Amal K.; Bhattacharya, Animesh; Raul, Moumita; Basuray, Amitabha

    2012-07-01

    Arithmetic logic unit (ALU) is the most important unit in any computing system. Optical computing is becoming popular day-by-day because of its ultrahigh processing speed and huge data handling capability. Obviously for the fast processing we need the optical TALU compatible with the multivalued logic. In this regard we are communicating the trinary arithmetic and logic unit (TALU) in modified trinary number (MTN) system, which is suitable for the optical computation and other applications in multivalued logic system. Here the savart plate and spatial light modulator (SLM) based optoelectronic circuits have been used to exploit the optical tree architecture (OTA) in optical interconnection network.

  20. Memory for Pictorial Information and the Picture Superiority Effect.

    Science.gov (United States)

    Maisto, Albert A.; Queen, Debbie Elaine

    1992-01-01

    The performance of 53 younger adults (mean age 20.7) and 52 older adults (mean age 68.3) was compared in a memory task involving pictures, words, and pictures-plus-words. Results showed (1) significantly higher recall scores for younger adults; (2) equivalent picture superiority effect for both groups; and (3) decline in older adults' performance…

  1. Memory effect in the high-temperature superconducting bulks

    International Nuclear Information System (INIS)

    Zhang, Xing-Yi; Zhou, Jun; Zhou, You-He

    2013-01-01

    Highlights: •Effects of temperature cycles on levitation force relaxation are investigated. •Memory effect of the YBCO bulks is observed in experiments. •With an increase of temperature, memory of the superconductor is gradually lost. -- Abstract: We present an experimental investigation of the relaxation of vertical force components in a high-temperature superconducting levitation system with different temperature cycle processes. For a selected ambient temperature (T 1 ) of the system, the experimental results show that the relaxations of the levitation forces are strongly dependent on the initial temperature. When the sample was submitted to temperature jumps around T 1 , the sample temperature was regulated at T 2 , and there were two cases of the experiments, ΔT = T 2 − T 1 0 (positive temperature cycle). It was found that in the case of negative temperature cycle, the superconducting samples have memory effect. And for the positive temperature cycle, with the experimental temperature increase, the memory effect of samples is gradually losing. Additionally, with the increase of temperature, the influences of the negative and positive temperature cycle on the levitation force relaxation are unsymmetrical. All the results are interpreted by using the characteristics of the free energy ‘ground’ plot of the Spin-glasses qualitatively

  2. Effects of Skill Training on Working Memory Capacity

    Science.gov (United States)

    Lee, Yuh-shiow; Lu, Min-ju; Ko, Hsiu-ping

    2007-01-01

    In this study we examined the effects of skill training, in particular mental abacus and music training, on working memory. Two groups of participants--children who had received mental abacus training and their controls--participated in Experiment 1. All participants performed the following span tasks: forward digit span, backward digit span,…

  3. Effect of background music on auditory-verbal memory performance

    Directory of Open Access Journals (Sweden)

    Sona Matloubi

    2014-12-01

    Full Text Available Background and Aim: Music exists in all cultures; many scientists are seeking to understand how music effects cognitive development such as comprehension, memory, and reading skills. More recently, a considerable number of neuroscience studies on music have been developed. This study aimed to investigate the effects of null and positive background music in comparison with silence on auditory-verbal memory performance.Methods: Forty young adults (male and female with normal hearing, aged between 18 and 26, participated in this comparative-analysis study. An auditory and speech evaluation was conducted in order to investigate the effects of background music on working memory. Subsequently, the Rey auditory-verbal learning test was performed for three conditions: silence, positive, and null music.Results: The mean score of the Rey auditory-verbal learning test in silence condition was higher than the positive music condition (p=0.003 and the null music condition (p=0.01. The tests results did not reveal any gender differences.Conclusion: It seems that the presence of competitive music (positive and null music and the orientation of auditory attention have negative effects on the performance of verbal working memory. It is possibly owing to the intervention of music with verbal information processing in the brain.

  4. Context-Dependent Repetition Effects on Recognition Memory

    Science.gov (United States)

    Opitz, Bertram

    2010-01-01

    One widely acknowledged way to improve our memory performance is to repeatedly study the to be learned material. One aspect that has received little attention in past research regards the context sensitivity of this repetition effect, that is whether the item is repeated within the same or within different contexts. The predictions of a…

  5. Effects of Aging and IQ on Item and Associative Memory

    Science.gov (United States)

    Ratcliff, Roger; Thapar, Anjali; McKoon, Gail

    2011-01-01

    The effects of aging and IQ on performance were examined in 4 memory tasks: item recognition, associative recognition, cued recall, and free recall. For item and associative recognition, accuracy and the response time (RT) distributions for correct and error responses were explained by Ratcliff's (1978) diffusion model at the level of individual…

  6. Effects of Methylphenidate on Working Memory Components: Influence of Measurement

    Science.gov (United States)

    Bedard, Anne-Claude; Jain, Umesh; Hogg-Johnson, Sheilah; Tannock, Rosemary

    2007-01-01

    Background: To investigate the effects of methylphenidate (MPH) on components of working memory (WM) in attention-deficit hyperactivity disorder (ADHD) and determine the responsiveness of WM measures to MPH. Methods: Participants were a clinical sample of 50 children and adolescents with ADHD, aged 6 to 16 years old, who participated in an acute…

  7. Effects of cannabis on eyewitness memory : A field study

    NARCIS (Netherlands)

    Vredeveldt, Annelies; Charman, Steve D.; den Blanken, Aukje; Hooydonk, Maren

    2018-01-01

    Eyewitnesses to crimes are regularly under the influence of drugs, such as cannabis. Yet there is very little research on how the use of cannabis affects eyewitness memory. In the present study, we assessed the effects of cannabis on eyewitness recall and lineup identification performance in a field

  8. Effect of Magnesium Administration on Passive Avoidance Memory ...

    African Journals Online (AJOL)

    However, one study has discussed the effect of diabetes on behavior, memory and learning [7]. Pain caused by peripheral nerve neuropathy is also one of the major clinical complaints described by patients with diabetes, and this affects the quality life of those concerned. Thus, alleviation of pain in these patients is of prime.

  9. Dissipative nucleus-nucleus collisions: study of memory effects

    International Nuclear Information System (INIS)

    Agarwal, K.C.; Yadav, H.L.

    2002-01-01

    Dissipative collisions between two heavy nuclei are described in terms of a macroscopic dynamical model within the framework of a multi-dimensional Fokker-Planck equation. The reaction 86 Kr(8.18 MeV/u) + 166 Er has been used as a prototype to study and demonstrate the memory effects for dissipation and diffusion processes

  10. Infants' Memory Processing of a Serial List: List Length Effects.

    Science.gov (United States)

    Gulya, Michele; Sweeney, Becky; Rovee-Collier, Carolyn

    1999-01-01

    Three experiments demonstrated that increasing the length of a mobile serial list impaired 6-month olds' memory for serial order. Findings indicated that the primacy effect was absent on a 24-hour delayed recognition test and was exhibited on a reactivation test, adding to growing evidence that young infants possess two functionally distinct…

  11. Effect of Magnesium Administration on Passive Avoidance Memory ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of oral consumption of magnesium on the memory and pain sensation of diabetic rats. Methods: A total of ... There was also a significant reduction in mean LT of untreated diabetic group (p < 0.001) as indicated by the increased number of animals that entered the dark compartment. Plasma ...

  12. Simulation for memory effect of Fick's first law†

    Indian Academy of Sciences (India)

    Administrator

    firmed by means of the 3D Monte Carlo simulation, where τ is the relaxation time, J is the flux of the diffus- ing particles, D is ... Fick's first law; memory effects; relaxation time; second sound; Monte Carlo simulation. 1. ..... According to the theory of the fluctuation of numbers ... example, the existing probability of a diffusing par-.

  13. Blinks of the mind : Memory effects of attentional processes

    NARCIS (Netherlands)

    Martens, S; Wolters, G; van Raamsdonk, M

    2002-01-01

    If 2 words are presented successively within 500 ms, subjects often miss the 2nd word. This attentional blink. reflects a limited capacity to attend to incoming information. Memory effects were studied for words that fell within an attentional blink. Unrelated words were presented in a modified

  14. Vantage perspective during encoding: The effects on phenomenological memory characteristics

    NARCIS (Netherlands)

    Mooren, N.; Krans, J.; Näring, G.W.B.; Moulds, M.L.; Minnen, A. van

    2016-01-01

    The vantage perspective from which a memory is retrieved influences the memory’s emotional impact, intrusiveness, and phenomenological characteristics. This study tested whether similar effects are observed when participants were instructed to imagine the events from a specific perspective. Fifty

  15. Effects of noise and working memory capacity on memory processing of speech for hearing-aid users.

    Science.gov (United States)

    Ng, Elaine Hoi Ning; Rudner, Mary; Lunner, Thomas; Pedersen, Michael Syskind; Rönnberg, Jerker

    2013-07-01

    It has been shown that noise reduction algorithms can reduce the negative effects of noise on memory processing in persons with normal hearing. The objective of the present study was to investigate whether a similar effect can be obtained for persons with hearing impairment and whether such an effect is dependent on individual differences in working memory capacity. A sentence-final word identification and recall (SWIR) test was conducted in two noise backgrounds with and without noise reduction as well as in quiet. Working memory capacity was measured using a reading span (RS) test. Twenty-six experienced hearing-aid users with moderate to moderately severe sensorineural hearing loss. Noise impaired recall performance. Competing speech disrupted memory performance more than speech-shaped noise. For late list items the disruptive effect of the competing speech background was virtually cancelled out by noise reduction for persons with high working memory capacity. Noise reduction can reduce the adverse effect of noise on memory for speech for persons with good working memory capacity. We argue that the mechanism behind this is faster word identification that enhances encoding into working memory.

  16. The quintuple-shape memory effect in electrospun nanofiber membranes

    Science.gov (United States)

    Zhang, Fenghua; Zhang, Zhichun; Liu, Yanju; Lu, Haibao; Leng, Jinsong

    2013-08-01

    Shape memory fibrous membranes (SMFMs) are an emerging class of active polymers, which are capable of switching from a temporary shape to their permanent shape upon appropriate stimulation. Quintuple-shape memory membranes based on the thermoplastic polymer Nafion, with a stable fibrous structure, are achieved via electrospinning technology, and possess a broad transition temperature. The recovery of multiple temporary shapes of electrospun membranes can be triggered by heat in a single triple-, quadruple-, quintuple-shape memory cycle, respectively. The fiber morphology and nanometer size provide unprecedented design flexibility for the adjustable morphing effect. SMFMs enable complex deformations at need, having a wide potential application field including smart textiles, artificial intelligence robots, bio-medical engineering, aerospace technologies, etc in the future.

  17. The effects of cardiovascular exercise on human memory

    DEFF Research Database (Denmark)

    Roig, Marc; Nordbrandt, Sasja; Geertsen, Svend Sparre

    2013-01-01

    We reviewed the evidence for the use of cardiovascular exercise to improve memory and explored potential mechanisms. Data from 29 and 21 studies including acute and long-term cardiovascular interventions were retrieved. Meta-analyses revealed that acute exercise had moderate (SMD=0.26; 95% CI=0.0.......03, 0.49; p=0.03; N=22) whereas long-term had small (SMD=0.15; 95% CI=0.02, 0.27; p=0.02; N=37) effects on short-term memory. In contrast, acute exercise showed moderate to large (SMD=0.52; 95% CI=0.28, 0.75; p......We reviewed the evidence for the use of cardiovascular exercise to improve memory and explored potential mechanisms. Data from 29 and 21 studies including acute and long-term cardiovascular interventions were retrieved. Meta-analyses revealed that acute exercise had moderate (SMD=0.26; 95% CI=0...

  18. The emotional memory effect: differential processing or item distinctiveness?

    Science.gov (United States)

    Schmidt, Stephen R; Saari, Bonnie

    2007-12-01

    A color-naming task was followed by incidental free recall to investigate how emotional words affect attention and memory. We compared taboo, nonthreatening negative-affect, and neutral words across three experiments. As compared with neutral words, taboo words led to longer color-naming times and better memory in both within- and between-subjects designs. Color naming of negative-emotion nontaboo words was slower than color naming of neutral words only during block presentation and at relatively short interstimulus intervals (ISIs). The nontaboo emotion words were remembered better than neutral words following blocked and random presentation and at both long and short ISIs, but only in mixed-list designs. Our results support multifactor theories of the effects of emotion on attention and memory. As compared with neutral words, threatening stimuli received increased attention, poststimulus elaboration, and benefit from item distinctiveness, whereas nonthreatening emotional stimuli benefited only from increased item distinctiveness.

  19. The quintuple-shape memory effect in electrospun nanofiber membranes

    International Nuclear Information System (INIS)

    Zhang, Fenghua; Zhang, Zhichun; Lu, Haibao; Leng, Jinsong; Liu, Yanju

    2013-01-01

    Shape memory fibrous membranes (SMFMs) are an emerging class of active polymers, which are capable of switching from a temporary shape to their permanent shape upon appropriate stimulation. Quintuple-shape memory membranes based on the thermoplastic polymer Nafion, with a stable fibrous structure, are achieved via electrospinning technology, and possess a broad transition temperature. The recovery of multiple temporary shapes of electrospun membranes can be triggered by heat in a single triple-, quadruple-, quintuple-shape memory cycle, respectively. The fiber morphology and nanometer size provide unprecedented design flexibility for the adjustable morphing effect. SMFMs enable complex deformations at need, having a wide potential application field including smart textiles, artificial intelligence robots, bio-medical engineering, aerospace technologies, etc in the future. (paper)

  20. Are animacy effects in episodic memory independent of encoding instructions?

    Science.gov (United States)

    Gelin, Margaux; Bugaiska, Aurélia; Méot, Alain; Bonin, Patrick

    2017-01-01

    The adaptive view of human memory [Nairne, J. S. 2010. Adaptive memory: Evolutionary constraints on remembering. In B. H. Ross (Ed.), The psychology of learning and motivation (Vol. 53 pp. 1-32). Burlington: Academic Press; Nairne, J. S., & Pandeirada, J. N. S. 2010a. Adaptive memory: Ancestral priorities and the mnemonic value of survival processing. Cognitive Psychology, 61, 1-22, 2010b; Memory functions. In The Corsini encyclopedia of psychology and behavioral science, (Vol 3, 4th ed. pp. 977-979). Hokoben, NJ: John Wiley & Sons] assumes that animates (e.g., baby, rabbit presented as words or pictures) are better remembered than inanimates (e.g., bottle, mountain) because animates are more important for fitness than inanimates. In four studies, we investigated whether the animacy effect in episodic memory (i.e., the better remembering of animates over inanimates) is independent of encoding instructions. Using both a factorial (Studies 1 and 3) and a multiple regression approach (Study 2), three studies tested whether certain contexts drive people to attend to inanimate more than to animate things (or the reverse), and therefore lead to differential animacy effects. The findings showed that animacy effects on recall performance were observed in the grassland-survival scenario used by Nairne, Thompson, and Pandeirada (2007. Adaptive memory: Survival processing enhances retention. Journal of Experimental Psychology: Learning, Memory, & Cognition, 33, 263-273) (Studies 1-3), when words were rated for their pleasantness (Study 2), and in explicit learning (Study 3). In the non-survival scenario of moving to a foreign land (Studies 1-2), animacy effects on recall rates were not reliable in Study 1, but were significant in Study 2, whereas these effects were reliable in the non-survival scenario of planning a trip as a tour guide (Study 3). A final (control) study (Study 4) was conducted to test specifically whether animacy effects are related to the more organised

  1. Colored noise and memory effects on formal spiking neuron models

    Science.gov (United States)

    da Silva, L. A.; Vilela, R. D.

    2015-06-01

    Simplified neuronal models capture the essence of the electrical activity of a generic neuron, besides being more interesting from the computational point of view when compared to higher-dimensional models such as the Hodgkin-Huxley one. In this work, we propose a generalized resonate-and-fire model described by a generalized Langevin equation that takes into account memory effects and colored noise. We perform a comprehensive numerical analysis to study the dynamics and the point process statistics of the proposed model, highlighting interesting new features such as (i) nonmonotonic behavior (emergence of peak structures, enhanced by the choice of colored noise characteristic time scale) of the coefficient of variation (CV) as a function of memory characteristic time scale, (ii) colored noise-induced shift in the CV, and (iii) emergence and suppression of multimodality in the interspike interval (ISI) distribution due to memory-induced subthreshold oscillations. Moreover, in the noise-induced spike regime, we study how memory and colored noise affect the coherence resonance (CR) phenomenon. We found that for sufficiently long memory, not only is CR suppressed but also the minimum of the CV-versus-noise intensity curve that characterizes the presence of CR may be replaced by a maximum. The aforementioned features allow to interpret the interplay between memory and colored noise as an effective control mechanism to neuronal variability. Since both variability and nontrivial temporal patterns in the ISI distribution are ubiquitous in biological cells, we hope the present model can be useful in modeling real aspects of neurons.

  2. Suppressing my memories by listening to yours: The effect of socially triggered context-based prediction error on memory.

    Science.gov (United States)

    Vlasceanu, Madalina; Drach, Rae; Coman, Alin

    2018-05-03

    The mind is a prediction machine. In most situations, it has expectations as to what might happen. But when predictions are invalidated by experience (i.e., prediction errors), the memories that generate these predictions are suppressed. Here, we explore the effect of prediction error on listeners' memories following social interaction. We find that listening to a speaker recounting experiences similar to one's own triggers prediction errors on the part of the listener that lead to the suppression of her memories. This effect, we show, is sensitive to a perspective-taking manipulation, such that individuals who are instructed to take the perspective of the speaker experience memory suppression, whereas individuals who undergo a low-perspective-taking manipulation fail to show a mnemonic suppression effect. We discuss the relevance of these findings for our understanding of the bidirectional influences between cognition and social contexts, as well as for the real-world situations that involve memory-based predictions.

  3. Recognition Memory and Source Memory in Autism Spectrum Disorder: A Study of the Intention Superiority and Enactment Effects

    Science.gov (United States)

    Grainger, Catherine; Williams, David M.; Lind, Sophie E.

    2017-01-01

    It is well established that neurotypical individuals generally show better memory for actions they have performed than actions they have observed others perform or merely read about, a so-called "enactment effect." Strikingly, research has also shown that neurotypical individuals demonstrate superior memory for actions they…

  4. Memory systems in the rat: effects of reward probability, context, and congruency between working and reference memory.

    Science.gov (United States)

    Roberts, William A; Guitar, Nicole A; Marsh, Heidi L; MacDonald, Hayden

    2016-05-01

    The interaction of working and reference memory was studied in rats on an eight-arm radial maze. In two experiments, rats were trained to perform working memory and reference memory tasks. On working memory trials, they were allowed to enter four randomly chosen arms for reward in a study phase and then had to choose the unentered arms for reward in a test phase. On reference memory trials, they had to learn to visit the same four arms on the maze on every trial for reward. Retention was tested on working memory trials in which the interval between the study and test phase was 15 s, 15 min, or 30 min. At each retention interval, tests were performed in which the correct WM arms were either congruent or incongruent with the correct RM arms. Both experiments showed that congruency interacted with retention interval, yielding more forgetting at 30 min on incongruent trials than on congruent trials. The effect of reference memory strength on the congruency effect was examined in Experiment 1, and the effect of associating different contexts with working and reference memory on the congruency effect was studied in Experiment 2.

  5. Time-dependent effects of cortisol on the contextualization of emotional memories.

    Science.gov (United States)

    van Ast, Vanessa A; Cornelisse, Sandra; Meeter, Martijn; Joëls, Marian; Kindt, Merel

    2013-12-01

    The inability to store fearful memories into their original encoding context is considered to be an important vulnerability factor for the development of anxiety disorders like posttraumatic stress disorder. Altered memory contextualization most likely involves effects of the stress hormone cortisol, acting via receptors located in the memory neurocircuitry. Cortisol via these receptors induces rapid nongenomic effects followed by slower genomic effects, which are thought to modulate cognitive function in opposite, complementary ways. Here, we targeted these time-dependent effects of cortisol during memory encoding and tested subsequent contextualization of emotional and neutral memories. In a double-blind, placebo-controlled design, 64 men were randomly assigned to one of three groups: 1) received 10 mg hydrocortisone 30 minutes (rapid cortisol effects) before a memory encoding task; 2) received 10 mg hydrocortisone 210 minutes (slow cortisol) before a memory encoding task; or 3) received placebo at both times. During encoding, participants were presented with neutral and emotional words in unique background pictures. Approximately 24 hours later, context dependency of their memories was assessed. Recognition data revealed that cortisol's rapid effects impair emotional memory contextualization, while cortisol's slow effects enhance it. Neutral memory contextualization remained unaltered by cortisol, irrespective of the timing of the drug. This study shows distinct time-dependent effects of cortisol on the contextualization of specifically emotional memories. The results suggest that rapid effects of cortisol may lead to impaired emotional memory contextualization, while slow effects of cortisol may confer protection against emotional memory generalization. © 2013 Society of Biological Psychiatry.

  6. Effects of load on the guidance of visual attention from working memory.

    Science.gov (United States)

    Zhang, Bao; Zhang, John X; Huang, Sai; Kong, Lingyue; Wang, Suiping

    2011-12-08

    An active recent line of research on working memory and attention has shown that the visual attention can be top-down guided by working memory contents. The present study examined whether the guidance effect is modulated by memory load, i.e., the amount of information maintained in working memory. In a set of three experiments, participants were asked to perform a visual search task while maintaining several objects in working memory. The memory-driven attentional guidance effect was observed in all experiments when there were spare working memory resources. When memory load was increased from one item to two items, there was no sign that the guidance effect was attenuated. When load was further increased to four items, the guidance effect disappeared completely, indicating a clear impact of memory load on attentional guidance. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. The Effect of Rehearsal Rate and Memory Load on Verbal Working Memory

    OpenAIRE

    Fegen, David; Buchsbaum, Bradley R.; D’Esposito, Mark

    2014-01-01

    While many neuroimaging studies have investigated verbal working memory (WM) by manipulating memory load, the subvocal rehearsal rate at these various memory loads has generally been left uncontrolled. Therefore, the goal of this study was to investigate how mnemonic load and the rate of subvocal rehearsal modulate patterns of activity in the core neural circuits underlying verbal working memory. Using fMRI in healthy subjects, we orthogonally manipulated subvocal rehearsal rate and memory lo...

  8. Martensitic transformation, shape memory effects, and other curious mechanical effects

    International Nuclear Information System (INIS)

    Vandermeer, R.A.

    1982-01-01

    The objective of this paper is to review tutorially the subject of martensitic transformations in uranium alloys emphasizing their role in the shape memory effect (SME). We examine first what a martensitic transformation is, illustrating some of its characteristics with specific examples. As well as being athermal in nature, as expected, data are presented indicating that martensitic transformations in some uranium alloys also have a strong isothermal component. In addition, a few alloys are known to exhibit thermoelastic martensitic reactions. The SME, which is associated with these, is defined and demonstrated graphically with data from a uranium-6 wt % niobium alloy. Some of the important variables influencing SME behavior are described. Specifically, these are reheat temperature, amount of deformation, crystal structure, and composition. A mechanism for SME is postulated and the association with martensitic transformation is detailed. A self-induced shape instability in the uranium-7.5 wt % niobium-2.5 wt % zirconium alloy with a rationalization of the behavior in terms of texture and lattice parameter change during aging is reviewed and discussed. 24 figures

  9. Enriched environment effects on remote object recognition memory.

    Science.gov (United States)

    Melani, Riccardo; Chelini, Gabriele; Cenni, Maria Cristina; Berardi, Nicoletta

    2017-06-03

    Since Ebbinghaus' classical work on oblivion and saving effects, we know that declarative memories may become at first spontaneously irretrievable and only subsequently completely extinguished. Recently, this time-dependent path toward memory-trace loss has been shown to correlate with different patterns of brain activation. Environmental enrichment (EE) enhances learning and memory and affects system memory consolidation. However, there is no evidence on whether and how EE could affect the time-dependent path toward oblivion. We used Object Recognition Test (ORT) to assess in adult mice put in EE for 40days (EE mice) or left in standard condition (SC mice) memory retrieval of the familiar objects 9 and 21days after learning with or without a brief retraining performed the day before. We found that SC mice show preferential exploration of new object at day 9 only with retraining, while EE mice do it even without. At day 21 SC mice do not show preferential exploration of novel object, irrespective of the retraining, while EE mice are still capable to benefit from retraining, even if they were not able to spontaneously recover the trace. Analysis of c-fos expression 20days after learning shows a different pattern of active brain areas in response to the retraining session in EE and SC mice, with SC mice recruiting the same brain network as naïve SC or EE mice following de novo learning. This suggests that EE promotes formation of longer lasting object recognition memory, allowing a longer time window during which saving is present. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Memory Effects Study of Measuring Radioactive Xenon Isotopes With β-γ Coincidence Method

    International Nuclear Information System (INIS)

    Jia Huaimao; Wang Shilian; Wang Jun; Li Qi; Zhao Yungang; Fan Yuanqing; Zhang Xinjun

    2010-01-01

    The β-γ coincidence technique is a kind of the key important method to detect radioactive xenon isotopes for the Comprehensive Nuclear-Test-Ban Treaty (CTBT). This paper describes noble gases memory effects of β-γ coincidence detector. Xenon memory effects were measured and its influence on detector's minimum detectable activity (MDA) was evaluated. The methods of reducing xenon memory effects were studied. In conclusion, aluminium coated plastic scintillator and YAP scintillator can remarkably decrease xenon memory effects. (authors)

  11. Glucose effects on long-term memory performance: duration and domain specificity.

    Science.gov (United States)

    Owen, Lauren; Finnegan, Yvonne; Hu, Henglong; Scholey, Andrew B; Sünram-Lea, Sandra I

    2010-08-01

    Previous research has suggested that long-term verbal declarative memory is particularly sensitive to enhancement by glucose loading; however, investigation of glucose effects on certain memory domains has hitherto been neglected. Therefore, domain specificity of glucose effects merits further elucidation. The aim of the present research was to provide a more comprehensive investigation of the possible effects of glucose administration on different aspects of memory by 1) contrasting the effect of glucose administration on different memory domains (implicit/explicit memory; verbal/non-verbal memory, and recognition/familiarity processes), 2) investigating whether potential effects on memory domains differ depending on the dose of glucose administered (25 g versus 60 g), 3) exploring the duration of the glucose facilitation effect (assessment of memory performance 35 min and 1 week after encoding). A double-blind between-subjects design was used to test the effects of administration of 25 and 60 g glucose on memory performance. Implicit memory was improved following administration of 60 g of glucose. Glucose supplementation failed to improve face recognition performance but significantly improved performance of word recall and recognition following administration of 60 g of glucose. However, effects were not maintained 1 week following encoding. Improved implicit memory performance following glucose administration has not been reported before. Furthermore, the current data tentatively suggest that level of processing may determine the required glucose dosage to demonstrate memory improvement and that higher dosages may be able to exert effects on memory pertaining to both hippocampal and non-hippocampal brain regions.

  12. The effect of evaluation on co-occurrence memory judgement.

    Science.gov (United States)

    Bar-Anan, Yoav; Amzaleg-David, Efrat

    2014-01-01

    Three experiments tested the effect of an attitude towards an object on the memory judgement of whether this object co-occurred with positive versus negative stimuli. We induced positive or negative attitudes towards novel male stimuli, and paired each man with an equal number of positive and negative animals. In a memory test, participants reported more co-occurrences of same-valence man/animal pairs than opposite-valence pairs. This valence-compatibility effect occurred even when attitudes were induced after the pairing (Experiment 1), when participants knew that each man occurred with an equal number of positive and negative animals (Experiment 2), and in reports of clear memory of pairs that did not co-occur (Experiment 3). The present findings suggest that evaluation causes illusory correlation even when the co-occurring stimuli are not traits or behaviours attributed to the attitude object. The results question the validity of co-occurrence memory judgements as measures of co-occurrence awareness in evaluative conditioning (EC) research.

  13. Effect of emotion on memory for words and their context.

    Science.gov (United States)

    Riegel, Monika; Wierzba, Małgorzata; Grabowska, Anna; Jednoróg, Katarzyna; Marchewka, Artur

    2016-06-01

    Emotion influences various cognitive processes, such as memory. This beneficial or detrimental effect can be studied with verbal material, yet in this case a broad term of context has to be taken into account. The present work reviews recent literature and proposes that traditional differentiation between semantic and environmental context should be replaced with a novel conceptualization of hippocampus-dependent relational memory and item memory (related to the activations of cuneus and left amygdala). Additionally, instead of list-learning paradigms, words should be memorized in the context of sentences or stories for better control over their meaning. The recent evidence suggests that of particular importance for ecological validity in research paradigms is the presence of communicative and social context of verbal material related to such processes as theory of mind and brain activations in temporoparietal junction, posterior cingulate cortex, and dorsal medial prefrontal cortex. We propose that studying memory of verbal material within context gives a better understanding of enhancing and impairing effects of emotion as well as of the underlying brain mechanisms. © 2015 Wiley Periodicals, Inc.

  14. Effects of arginine vasopressin on musical working memory.

    Science.gov (United States)

    Granot, Roni Y; Uzefovsky, Florina; Bogopolsky, Helena; Ebstein, Richard P

    2013-01-01

    Previous genetic studies showed an association between variations in the gene coding for the 1a receptor of the neuro-hormone arginine vasopressin (AVP) and musical working memory (WM). The current study set out to test the influence of intranasal administration (INA) of AVP on musical as compared to verbal WM using a double blind crossover (AVP-placebo) design. Two groups of 25 males were exposed to 20 IU of AVP in one session, and 20 IU of saline water (placebo) in a second session, 1 week apart. In each session subjects completed the tonal subtest from Gordon's "Musical Aptitude Profile," the interval subtest from the "Montreal Battery for Evaluation of Amusias (MBEA)," and the forward and backward digit span tests. Scores in the digit span tests were not influenced by AVP. In contrast, in the music tests there was an AVP effect. In the MBEA test, scores for the group receiving placebo in the first session (PV) were higher than for the group receiving vasopressin in the first session (VP) (p music test these scores were significantly correlated with memory scores. Together the results reflect a complex interaction between AVP, musical memory, arousal, and contextual effects such as session, and base levels of memory. The results are interpreted in light of music's universal use as a means to modulate arousal on the one hand, and AVP's influence on mood, arousal, and social interactions on the other.

  15. Memory and Evaluation Effects in Competitive Advertising Environments.

    OpenAIRE

    Keller, Kevin Lane

    1991-01-01

    A laboratory experiment replicates and extends prior research on how competitive advertising and retrieval cues affect consumer memory and evaluations of brands. The number and valence of competing ads, presence of ad retrieval cues, and valence of target ads were manipulated. A high level of competitive advertising varying in valence produced interference effects for recall and evaluations. Ad retrieval cues offset these effects and enhanced recall and evaluations even when there were no com...

  16. Effective visual working memory capacity: an emergent effect from the neural dynamics in an attractor network.

    Directory of Open Access Journals (Sweden)

    Laura Dempere-Marco

    Full Text Available The study of working memory capacity is of outmost importance in cognitive psychology as working memory is at the basis of general cognitive function. Although the working memory capacity limit has been thoroughly studied, its origin still remains a matter of strong debate. Only recently has the role of visual saliency in modulating working memory storage capacity been assessed experimentally and proved to provide valuable insights into working memory function. In the computational arena, attractor networks have successfully accounted for psychophysical and neurophysiological data in numerous working memory tasks given their ability to produce a sustained elevated firing rate during a delay period. Here we investigate the mechanisms underlying working memory capacity by means of a biophysically-realistic attractor network with spiking neurons while accounting for two recent experimental observations: 1 the presence of a visually salient item reduces the number of items that can be held in working memory, and 2 visually salient items are commonly kept in memory at the cost of not keeping as many non-salient items. Our model suggests that working memory capacity is determined by two fundamental processes: encoding of visual items into working memory and maintenance of the encoded items upon their removal from the visual display. While maintenance critically depends on the constraints that lateral inhibition imposes to the mnemonic activity, encoding is limited by the ability of the stimulated neural assemblies to reach a sufficiently high level of excitation, a process governed by the dynamics of competition and cooperation among neuronal pools. Encoding is therefore contingent upon the visual working memory task and has led us to introduce the concept of effective working memory capacity (eWMC in contrast to the maximal upper capacity limit only reached under ideal conditions.

  17. Effective visual working memory capacity: an emergent effect from the neural dynamics in an attractor network.

    Science.gov (United States)

    Dempere-Marco, Laura; Melcher, David P; Deco, Gustavo

    2012-01-01

    The study of working memory capacity is of outmost importance in cognitive psychology as working memory is at the basis of general cognitive function. Although the working memory capacity limit has been thoroughly studied, its origin still remains a matter of strong debate. Only recently has the role of visual saliency in modulating working memory storage capacity been assessed experimentally and proved to provide valuable insights into working memory function. In the computational arena, attractor networks have successfully accounted for psychophysical and neurophysiological data in numerous working memory tasks given their ability to produce a sustained elevated firing rate during a delay period. Here we investigate the mechanisms underlying working memory capacity by means of a biophysically-realistic attractor network with spiking neurons while accounting for two recent experimental observations: 1) the presence of a visually salient item reduces the number of items that can be held in working memory, and 2) visually salient items are commonly kept in memory at the cost of not keeping as many non-salient items. Our model suggests that working memory capacity is determined by two fundamental processes: encoding of visual items into working memory and maintenance of the encoded items upon their removal from the visual display. While maintenance critically depends on the constraints that lateral inhibition imposes to the mnemonic activity, encoding is limited by the ability of the stimulated neural assemblies to reach a sufficiently high level of excitation, a process governed by the dynamics of competition and cooperation among neuronal pools. Encoding is therefore contingent upon the visual working memory task and has led us to introduce the concept of effective working memory capacity (eWMC) in contrast to the maximal upper capacity limit only reached under ideal conditions.

  18. Effective Visual Working Memory Capacity: An Emergent Effect from the Neural Dynamics in an Attractor Network

    Science.gov (United States)

    Dempere-Marco, Laura; Melcher, David P.; Deco, Gustavo

    2012-01-01

    The study of working memory capacity is of outmost importance in cognitive psychology as working memory is at the basis of general cognitive function. Although the working memory capacity limit has been thoroughly studied, its origin still remains a matter of strong debate. Only recently has the role of visual saliency in modulating working memory storage capacity been assessed experimentally and proved to provide valuable insights into working memory function. In the computational arena, attractor networks have successfully accounted for psychophysical and neurophysiological data in numerous working memory tasks given their ability to produce a sustained elevated firing rate during a delay period. Here we investigate the mechanisms underlying working memory capacity by means of a biophysically-realistic attractor network with spiking neurons while accounting for two recent experimental observations: 1) the presence of a visually salient item reduces the number of items that can be held in working memory, and 2) visually salient items are commonly kept in memory at the cost of not keeping as many non-salient items. Our model suggests that working memory capacity is determined by two fundamental processes: encoding of visual items into working memory and maintenance of the encoded items upon their removal from the visual display. While maintenance critically depends on the constraints that lateral inhibition imposes to the mnemonic activity, encoding is limited by the ability of the stimulated neural assemblies to reach a sufficiently high level of excitation, a process governed by the dynamics of competition and cooperation among neuronal pools. Encoding is therefore contingent upon the visual working memory task and has led us to introduce the concept of effective working memory capacity (eWMC) in contrast to the maximal upper capacity limit only reached under ideal conditions. PMID:22952608

  19. INDIVIDUAL DIFFERENCES IN WORKING MEMORY PERFORMANCE: «OVERLOAD» EFFECT

    Directory of Open Access Journals (Sweden)

    Yuri G. Pavlov

    2015-01-01

    Full Text Available The aim of this research is to study the relationship betweenfrontal midline theta rhythm changes and individual differences in working memory performance.Methods. The methods involve behavioural testing on the basis of the program for a presentation of stimulus and registration of answers «PsyTask»; method of EEG (electroencephalography; a technique of measurement of efficiency of working memory; the comparative analysis. Software packages EEGLab for Matlab and Fieldtrip are applied while data processing.Results. After the behavioral test all subjects were separated into 2 groups according to their performance: with «highly productive» and «low productive» memory. Specially prepared author’s complete set of the tasks which complexity varied from average to ultrahigh level was offered to participants of experiment –students and employees of the Ural Federal University and Ural Legal Institute of the Ministry of Internal Affairs. Working memory tasks included sets of verbal stimuli for memorizing in strict order without any mental manipulation and sets of similar stimuli for memorizing in alphabetical order (with manipulations. Measured characteristics of theta-rhythm of EEG during information deduction in memory were compared of two groups’ representatives. The obtained data has shown rather uniform and similar dynamics of decrease in quantity of right answers in process of increasing tasks’ complexity. However, changes of a thetarhythm in different groups had sharply expressed distinctions. «Highly productive» examinees have systematic expansion of a theta-rhythm in the central assignments with stabilisation on the most difficult tasks; «low productive» – while tasks performance of average complexity, a sharp falling of theta-rhythm activity is observed after achievement of its maximum activation.Scientific novelty. The working memory «overload» effect and its EEG correlates are demonstrated on a big sample of

  20. Modulatory mechanisms of cortisol effects on emotional learning and memory: Novel perspectives

    NARCIS (Netherlands)

    Ast, V.A. van; Cornelisse, S.; Marin, M.F.; Ackermann, S.; Garfinkel, S.N.; Abercrombie, H.C.

    2013-01-01

    It has long been known that cortisol affects learning and memory processes. Despite a wealth of research dedicated to cortisol effects on learning and memory, the strength or even directionality of the effects often vary. A number of the factors that alter cortisol's effects on learning and memory

  1. Shape memory effects, thermal expansion and B19' martensite texture in titanium nickelide

    International Nuclear Information System (INIS)

    Zel'dovich, V.I.; Sobyanina, G.A.; Rinkevich, O.S.; Gundyrev, V.M.

    1996-01-01

    The influence of plastic deformation by tension and cold rolling on shape memory effect, reverse shape memory effect, thermal expansion and texture state of martensite in titanium nickelide is under study. The relationship of thermal expansion coefficient to the value of strain during direct and reverse shape memory effect is established

  2. The Effect of Memory and Attention Rehabilitation to Decrease of Memory Deficits in Older Adults With Alzheimer Disease

    Directory of Open Access Journals (Sweden)

    Mehdi Amini

    2013-10-01

    Full Text Available Objectives: Alzheimer's disease is a chronic problem and most common demantic disorders in elderly. That has high cost for elders and them family. In this study, we examined the effect of memory and attention rehabilitation, a new and non-pharmacological approach to reduce memory defecits in Alzheimer's disease. Methods & Materials: This study was a quasi-experimental research, in single-subject study -Time-series with control group- and based on A-B design. That was conducted in two group of control and experimental in order to evaluate effectiveness of memory and attention rehabilitation, to decrease of memory deficits in elders with Alzheimer's disease. Subject consisted of eight patients (4 controls and 4 experiments with mild to moderate Alzheimer's disease. For experiment group, memory and attention rehabilitation were held in 45 minutes -1 hour session, twice weekly for 7 weeks. For data collection, patient evaluated by MMSE, GDS-15, WMS-O, in 1 and 14 sessions, and with Logical memory, Learning associations and Digit span subscales of WMS-O, and Coding subscale from WAIS-R in 1, 5, 8, 11 and 14 sessions. Statically analysis was done by visual inspection of graphed data, effect size and improvement percent for individuals and groups. Results: The analysis of data showed that memory functions in the paired patients and groups before the intervention was similar, but after procedures experimental patients showed increasing in level of functions and show significant effect size (d= 3.17-1.22, and significant improvement percent in memory functions. Conclusion: Consequently, the hypothesis of this study memory and attention rehabilitation decrease the memory function in elders with Alzheimer’s disease, such hypothesis was confirmed.

  3. Memory effects and peak effect in type II superconductors

    International Nuclear Information System (INIS)

    Pasquini, G.; Luna, D.; Eismann, B.; Bettachini, V.; Bekeris, V.

    2007-01-01

    A large amount of experimental and theoretical work has been devoted to understand memory effects (ME) in the solid vortex lattice (VL) but has remained, however, controversial until now. In the vicinity of the anomaly known as the peak effect (PE) both the VL mobility and the measured critical current density are found to be dependent of the dynamical history of the sample, in both low T c (LTS) and high T c (HTS) superconductors. Experiments in YBa 2 Cu 3 O 7 (YBCO) crystals have shown that the mobility of the VL increases after assisting the system with a symmetric AC field (or current) of moderated amplitude. On the other hand, after an asymmetric AC field assists vortices, the VL becomes less mobile. These features indicate that ME in these samples cannot be ascribed to an equilibration process, but probably are related to the organization of the lattice after nearest neighbor re-accommodation or induced plastic VL deformation. Recently, we have shown evidence that in YBCO the PE is a dynamic anomaly observed in the non-linear response, and is absent in the Labusch constant derived from the linear Campbell regime. However, this behavior seems not to be extensive to other systems as the traditional LTS NbSe 2 . In this work, the AC response in the PE region of NbSe 2 and YBCO samples are presented and compared. Very salient differences both in the linear and non-linear response as well as in the ME characteristics indicate that a different physics governs the PE phenomena in each case

  4. Effects of noise and working memory capacity on memory processing of speech for hearing-aid users

    OpenAIRE

    Ng, Hoi Ning, Elaine; Rudner, Mary; Lunner, Thomas; Syskind Perdersen, Michael; Rönnberg, Jerker

    2013-01-01

    Objectives: It has been shown that noise reduction algorithms can reduce the negative effects of noise on memory processing in persons with normal hearing. The objective of the present study was to investigate whether a similar effect can be obtained for persons with hearing impairment and whether such an effect is dependent on individual differences in working memory capacity. Design: A sentence-final word identification and recall (SWIR) test was conducted in two noise backgrounds with and ...

  5. Hormones, stress, and cognition: The effects of glucocorticoids and oxytocin on memory

    Science.gov (United States)

    Wirth, Michelle M.

    2014-01-01

    Hormones have nuanced effects on learning and memory processes. The degree and direction of the effect (e.g., is memory impaired or enhanced?) depends on the dose, type and stage of memory, and type of material being learned, among other factors. This review will focus on two specific topics within the realm of effects of hormones on memory: (1) How glucocorticoids (the output hormones of the hypothalamic-pituitary-adrenal axis) affect long-term memory consolidation, retrieval, and working memory, with a focus on neural mechanisms and effects of emotion; and (2) How oxytocin affects memory, with emphasis on a speculative hypothesis that oxytocin might exert its myriad effects on human social cognition and behavior via impacts on more general cognitive processes. Oxytocin-glucocorticoid interactions will be briefly addressed. These effects of hormones on memory will also be considered from an evolutionary perspective. PMID:25893159

  6. Memory effects in dissipative nucleus-nucleus collision

    International Nuclear Information System (INIS)

    Yadav, H.L.; Agarwal, K.C.

    2002-01-01

    A macroscopic dynamical model within the framework of a multidimensional Fokker-Planck equation is employed for a theoretical description of low-energy dissipative collisions between two heavy nuclei. The effect of two-body collisions leading to intrinsic equilibrium has been treated phenomenologically using the basic concepts of dissipative diabatic dynamics. The heavy-ion reaction 86 Kr(8.18 MeV/u) + 166 Er has been as a prototype to study and demonstrate the memory effects for dissipation and diffusion processes. Our calculated results for the deflection angle, angular distributions dσ/dθ cm , energy distributions dσ/dΔΕ, and element distributions dσ/dΖ illustrate a remarkable dependence on the memory effects and are consistent with the experimental data

  7. Memory effects in dissipative nucleus-nucleus collision

    CERN Document Server

    Yadav, H L

    2002-01-01

    A macroscopic dynamical model within the framework of a multidimensional Fokker-Planck equation is employed for a theoretical description of low-energy dissipative collisions between two heavy nuclei. The effect of two-body collisions leading to intrinsic equilibrium has been treated phenomenologically using the basic concepts of dissipative diabatic dynamics. The heavy-ion reaction sup 8 sup 6 Kr(8.18 MeV/u) + sup 1 sup 6 sup 6 Er has been as a prototype to study and demonstrate the memory effects for dissipation and diffusion processes. Our calculated results for the deflection angle, angular distributions d sigma/d theta sub c sub m , energy distributions d sigma/d DELTA EPSILON, and element distributions d sigma/d ZETA illustrate a remarkable dependence on the memory effects and are consistent with the experimental data

  8. Memory effects in nonadiabatic molecular dynamics at metal surfaces

    DEFF Research Database (Denmark)

    Olsen, Thomas; Schiøtz, Jakob

    2010-01-01

    We study the effect of temporal correlation in a Langevin equation describing nonadiabatic dynamics at metal surfaces. For a harmonic oscillator, the Langevin equation preserves the quantum dynamics exactly and it is demonstrated that memory effects are needed in order to conserve the ground state...... energy of the oscillator. We then compare the result of Langevin dynamics in a harmonic potential with a perturbative master equation approach and show that the Langevin equation gives a better description in the nonperturbative range of high temperatures and large friction. Unlike the master equation......, this approach is readily extended to anharmonic potentials. Using density functional theory, we calculate representative Langevin trajectories for associative desorption of N-2 from Ru(0001) and find that memory effects lower the dissipation of energy. Finally, we propose an ab initio scheme to calculate...

  9. Adaptive memory: Is the animacy effect on memory due to emotional arousal?

    Science.gov (United States)

    Meinhardt, Martin J; Bell, Raoul; Buchner, Axel; Röer, Jan P

    2018-05-07

    Animate entities are often better remembered than inanimate ones. The proximal mechanisms underlying this animacy effect on recall are unclear. In two experiments, we tested whether the animacy effect is due to emotional arousal. Experiment 1 revealed that translations of the animate words used in the pioneering study of Nairne et al. (Psychological science, 24, 2099-2105, 2013) were perceived as being more arousing than translations of the inanimate words, suggesting that animacy might have been confounded with arousal in previous studies. In Experiment 2, new word lists were created in which the animate and inanimate words were matched on arousal (amongst several other dimensions), and participants were required to reproduce the animate and inanimate words in a free recall task. There was a tendency towards better memory for arousing items, but robust animacy effects were obtained even though animate and inanimate words were matched on arousal. Thus, while arousal may contribute to the animacy effect when it is not carefully controlled for, it cannot explain the memory advantage of animate items.

  10. Acute effects of alcohol on intrusive memory development and viewpoint dependence in spatial memory support a dual representation model.

    Science.gov (United States)

    Bisby, James A; King, John A; Brewin, Chris R; Burgess, Neil; Curran, H Valerie

    2010-08-01

    A dual representation model of intrusive memory proposes that personally experienced events give rise to two types of representation: an image-based, egocentric representation based on sensory-perceptual features; and a more abstract, allocentric representation that incorporates spatiotemporal context. The model proposes that intrusions reflect involuntary reactivation of egocentric representations in the absence of a corresponding allocentric representation. We tested the model by investigating the effect of alcohol on intrusive memories and, concurrently, on egocentric and allocentric spatial memory. With a double-blind independent group design participants were administered alcohol (.4 or .8 g/kg) or placebo. A virtual environment was used to present objects and test recognition memory from the same viewpoint as presentation (tapping egocentric memory) or a shifted viewpoint (tapping allocentric memory). Participants were also exposed to a trauma video and required to detail intrusive memories for 7 days, after which explicit memory was assessed. There was a selective impairment of shifted-view recognition after the low dose of alcohol, whereas the high dose induced a global impairment in same-view and shifted-view conditions. Alcohol showed a dose-dependent inverted "U"-shaped effect on intrusions, with only the low dose increasing the number of intrusions, replicating previous work. When same-view recognition was intact, decrements in shifted-view recognition were associated with increases in intrusions. The differential effect of alcohol on intrusive memories and on same/shifted-view recognition support a dual representation model in which intrusions might reflect an imbalance between two types of memory representation. These findings highlight important clinical implications, given alcohol's involvement in real-life trauma. Copyright 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  11. Age differences and schema effects in memory for crime information.

    Science.gov (United States)

    Overman, Amy A; Wiseman, Kimberly D; Allison, Meredith; Stephens, Joseph D W

    2013-01-01

    BACKGROUND/STUDY CONTEXT: This study investigated age-related differences in memory for crime information. Older adults have been found to rely more than young adults on schema- and stereotype-based processing in memory, and such age differences may have implications in the criminal justice system. Some prior research has examined schema-based processing among older adults in legal settings, but no studies have tested for schema effects on older adults' memory for specific details of a crime. Older adults (N = 56, ages 65-93) and young adults (N = 52, ages 18-22) read a passage about a criminal suspect's "bad" or "good" childhood, and then read a crime report containing incriminating, exonerating, and neutral details with regard to the suspect. Participants were subsequently tested on recognition of accurate versus altered details from the crime report. Participants also rated the suspect"s guilt, and completed a battery of neuropsychological tests. Correct and false recognition rates were analyzed with ANOVA to compare means across age group, evidence type, and background type, and guilt ratings were analyzed with linear regression using neuropsychological scores as predictors. Among older adults, an interaction was found between evidence type (incriminating/exonerating) and suspect's background (good/bad childhood) in false recognition of altered details from the crime report, supporting the hypothesis that schema-based processing influenced older adult memory from crime information. Additionally, although guilt ratings were not related to the suspect's background for either age group, they were predicted by older adults' short-delay recall (β = -.37), suggesting that cognitive decline may play a role in older adults' interpretations of evidence. The findings suggest reduced cognitive capacity in older adults increases schema-based processing in memory for crime information, and are consistent with research in other domains that has demonstrated greater schema

  12. Inconsistency effects in source memory and compensatory schema-consistent guessing.

    Science.gov (United States)

    Küppers, Viviane; Bayen, Ute J

    2014-10-01

    The attention-elaboration hypothesis of memory for schematically unexpected information predicts better source memory for unexpected than expected sources. In three source-monitoring experiments, the authors tested the occurrence of an inconsistency effect in source memory. Participants were presented with items that were schematically either very expected or very unexpected for their source. Multinomial processing tree models were used to separate source memory, item memory, and guessing bias. Results show an inconsistency effect in source memory accompanied by a compensatory schema-consistent guessing bias when expectancy strength is high, that is, when items are very expected or very unexpected for their source.

  13. Tunnel field-effect transistor charge-trapping memory with steep subthreshold slope and large memory window

    Science.gov (United States)

    Kino, Hisashi; Fukushima, Takafumi; Tanaka, Tetsu

    2018-04-01

    Charge-trapping memory requires the increase of bit density per cell and a larger memory window for lower-power operation. A tunnel field-effect transistor (TFET) can achieve to increase the bit density per cell owing to its steep subthreshold slope. In addition, a TFET structure has an asymmetric structure, which is promising for achieving a larger memory window. A TFET with the N-type gate shows a higher electric field between the P-type source and the N-type gate edge than the conventional FET structure. This high electric field enables large amounts of charges to be injected into the charge storage layer. In this study, we fabricated silicon-oxide-nitride-oxide-semiconductor (SONOS) memory devices with the TFET structure and observed a steep subthreshold slope and a larger memory window.

  14. Effects of Arginine Vasopressin on musical short-term memory

    Directory of Open Access Journals (Sweden)

    Roni Y. Granot

    2013-10-01

    Full Text Available Previous genetic studies showed an association between variations in the gene coding for the 1a receptor of the neuro-hormone arginine vasopressin (AVP and musical working memory (WM. The current study set out to test the influence of intranasal administration (INA of AVP on musical as compared to verbal WM using a double blind crossover (AVP – placebo design. Two groups of 25 males were exposed to 20 IU of AVP in one session, and 20 IU of saline water (placebo in a second session, one week apart. In each session subjects completed the tonal subtest from Gordon's Musical Aptitude Profile, the interval subtest from the Montreal Battery for Evaluation of Amusias (MBEA, and the forward and backward digit span tests. Scores in the digit span tests were not influenced by AVP. In contrast, in the music tests there was an AVP effect. In the MBEA test, scores for the group receiving placebo in the first session (PV were higher than for the group receiving vasopressin in the first session (VP (p < .05 with no main Session effect nor Group * Session interaction. In the Gordon test there was a main Session effect (p < .05 with scores higher in the second as compared to the first session, a marginal main Group effect (p = .093 and a marginal Group X Session interaction (p = 0.88. In addition we found that the group that received AVP in the first session scored higher on scales indicative of happiness, and alertness on the Positive and Negative Affect Scale, (PANAS. Only in this group and only in the music test these scores were significantly correlated with memory scores. Together the results reflect a complex interaction between AVP, musical memory, arousal, and contextual effects such as session, and base levels of memory. The results are interpreted in light of music's universal use as a means to modulate arousal on the one hand, and AVP's influence on mood, arousal, and social interactions on the other.

  15. Memory effects on mechanically stimulated electric signal; diversification of stimuli impact on material memory and comments on the observed features

    Science.gov (United States)

    Kyriazis, Panagiotis; Stavrakas, Ilias; Anastasiadis, Cimon; Triantis, Dimos; Stonham, John

    2010-05-01

    Memory is defined as the ability of marble and generally of brittle geomaterials to retain 'imprints' from previous treatments and to reproduce information about these treatments under certain conditions, by analogy to the memory of human beings. Memory effects have been observed in the evolution of a variety of physical properties like the acoustic emissions of brittle materials during fracture. The existence of memory effects for the mechanically stimulated electric signal, either by Pressure (PSC) or by Bending (BSC), is examined in this work, alongside with an attempt to distinguish between the two different manifestations of 'memory' based on the electrification mechanism that is triggered at different levels of externally applied load on samples. Having identified two main mechanisms (i.e. the dynamic and the cracking) and following the human memory model, we suggest the separation of memory of a material specimen into two levels i.e. the short or temporary and long or permanent memory. For the observation and analysis of the short memory of brittle materials we have conducted experiments using the PSC technique in marble specimens. The materials are imposed to cyclic stepwise loading of the same level, scheme and direction (axial stress - unchanged position of material) in order to comply with the conditions that are proposed as suitable for memory effects study by other researchers. We have also conducted experimental tests of cyclic high level stepwise loading on amphibolite rock specimens in order to verify and study the existence of permanent memory effects. Modelling the signal recordings and studying the effects of memory on the signals, we have identified certain trends manifestation for the two types of memory that are summarised to the following points. (a) Both types of memory influence the PSC peaks evolution (exponential decrease) in cyclic loadings of the same level. (b) Permanent memory cannot be erased and affects PSC signal permanently and

  16. A triazolam/amphetamine dose-effect interaction study: dissociation of effects on memory versus arousal.

    Science.gov (United States)

    Mintzer, Miriam Z; Griffiths, Roland R

    2007-06-01

    In addition to producing robust memory impairment, benzodiazepines also induce marked sedation. Thus, it is possible that the observed amnestic effects are secondary to more global sedative effects and do not reflect a specific primary benzodiazepine effect on memory mechanisms. The objective was to use the nonspecific stimulant d-amphetamine to dissociate the sedative and memory-impairing effects of the benzodiazepine triazolam. Single oral doses of placebo, triazolam alone (0.25, 0.50 mg/70 kg), d-amphetamine sulfate alone (20, 30 mg/70 kg), and triazolam (0.25, 0.50 mg/70 kg) and d-amphetamine sulfate (20, 30 mg/70 kg) conjointly (at all dose combinations) were administered to 18 healthy adult participants across nine sessions in a double-blind, staggered-dosing, crossover design. In addition to standard data analyses, analyses were also conducted on z-score standardized data, enabling effects to be directly compared across measures. Relative to the sedative measures, the memory measures generally exhibited a pattern of less reversal of triazolam's effects by d-amphetamine. The memory measures ranged in degree of reversal such that the most reversal was observed for reaction time on the n-back working memory task, and the least reversal was observed for accuracy on the Sternberg working memory task, with most measures showing an overall pattern of partial reversal. Benzodiazepines have specific effects on memory that are not merely a by-product of the drugs' sedative effects, and the degree to which sedative effects contribute to the amnestic effects varies as a function of the particular memory process being assessed.

  17. Effects of walnuts (Juglans regia) on learning and memory functions.

    Science.gov (United States)

    Haider, Saida; Batool, Zehra; Tabassum, Saiqa; Perveen, Tahira; Saleem, Sadia; Naqvi, Fizza; Javed, Huma; Haleem, Darakhshan J

    2011-11-01

    Walnut has been regarded as a health food that is delicious and nutritious. Both preventive and therapeutic effects of walnut are well documented. Walnuts are rich in omega-3 fatty acids that are reported to have beneficial effects on brain function. The present work was designed to evaluate the effects of walnuts on learning and memory in male rats. The effect of oral intake of walnut was also monitored on food intake. Walnut was given orally to rats for a period of 28 days. Memory function in rats was assessed by elevated plus maze (EPM) and radial arm maze (RAM). A significant improvement in learning and memory of walnut treated rats compared to controls was observed. Walnut treated rats also exhibited a significant decrease in food intake while the change in growth rate (in terms of percentage) remained comparable between the two groups. Analysis of brain monoamines exhibited enhanced serotonergic levels in rat brain following oral intake of walnuts. The findings suggest that walnut may exert its hypophagic and nootropic actions via an enhancement of brain 5-HT metabolism.

  18. How "implicit" are implicit color effects in memory?

    Science.gov (United States)

    Zimmer, Hubert D; Steiner, Astrid; Ecker, Ullrich K H

    2002-01-01

    Processing colored pictures of objects results in a preference to choose the former color for a specific object in a subsequent color choice test (Wippich & Mecklenbräuker, 1998). We tested whether this implicit memory effect is independent of performances in episodic color recollection (recognition). In the study phase of Experiment 1, the color of line drawings was either named or its appropriateness was judged. We found only weak implicit memory effects for categorical color information. In Experiment 2, silhouettes were colored by subjects during the study phase. Performances in both the implicit and the explicit test were good. Selections of "old" colors in the implicit test, though, were almost completely confined to items for which the color was also remembered explicitly. In Experiment 3, we applied the opposition technique in order to check whether we could find any implicit effects regarding items for which no explicit color recollection was possible. This was not the case. We therefore draw the conclusion that implicit color preference effects are not independent of explicit recollection, and that they are probably based on the same episodic memory traces that are used in explicit tests.

  19. The hard fall effect: high working memory capacity leads to a higher, but less robust short-term memory performance.

    Science.gov (United States)

    Thomassin, Noémylle; Gonthier, Corentin; Guerraz, Michel; Roulin, Jean-Luc

    2015-01-01

    Participants with a high working memory span tend to perform better than low spans in a variety of tasks. However, their performance is paradoxically more impaired when they have to perform two tasks at once, a phenomenon that could be labeled the "hard fall effect." The present study tested whether this effect exists in a short-term memory task, and investigated the proposal that the effect is due to high spans using efficient facilitative strategies under simple task conditions. Ninety-eight participants performed a spatial short-term memory task under simple and dual task conditions; stimuli presentation times either allowed for the use of complex facilitative strategies or not. High spans outperformed low spans only under simple task conditions when presentation times allowed for the use of facilitative strategies. These results indicate that the hard fall effect exists on a short-term memory task and may be caused by individual differences in strategy use.

  20. Examination of the bidirectional influences of leisure activity and memory in old people: a dissociative effect on episodic memory.

    Science.gov (United States)

    Mousavi-Nasab, S-M-Hossein; Kormi-Nouri, Reza; Nilsson, Lars-Göran

    2014-08-01

    The present study examined the relationships between different types of social and cognitive activities and different types of episodic and semantic memory. A total of 794 adult men and women from five age cohorts (aged 65-85 at baseline), participating in the longitudinal Betula project on ageing, memory, and health, were included in the study. The participants were studied over 10 years (1995-2005) in three waves. Recognition and recall were used as episodic memory tasks, and knowledge and verbal fluency as semantic memory tasks. The results, after controlling for age, gender, education, and some diseases, including heart disease and hypertension, as covariates, showed unidirectional effects of social activity on episodic memory on all test occasions (β = .10). Also, episodic memory predicted change in cognitive activity for all test waves (β = .21-.22). Findings suggest that social activity can be seen as protective factor against memory decline. It also seems that episodic memory performance is a predictor of cognitive activity in old people. However, the opposite direction does not hold true. © 2013 The British Psychological Society.

  1. Memory and convulsive stimulation: effects of stimulus waveform.

    Science.gov (United States)

    Spanis, C W; Squire, L R

    1981-09-01

    Electrical stimulation with brief pulses can produce a seizure requiring less energy than conventional sine-wave stimulation, and it has been suggested that brief-pulse stimulation might reduce the memory loss associated with electroconvulsive therapy (ECT). The authors evaluated the effects of electroconvulsive shock (ECS) on memory in mice by using various waveforms, current intensities, training-ECS intervals, pulse widths, and stimulus durations. When equated for ability to produce seizures, low-energy, brief-pulse stimulation caused as much amnesia as sine-wave stimulation and sometimes more. In the absence of comparisons of the amnesic effects of brief-pulse and sine-wave stimulation in humans, the use of brief pulses for administering ECT is unwarranted.

  2. Information Updating in Working Memory: Its Effect on Teacher Efficacy

    Directory of Open Access Journals (Sweden)

    Jun Tao

    2012-01-01

    Full Text Available Teacher efficacy has a great impact on effective teaching and has been studied in various perspectives. The updating information ability in working memory is always related with many capabilities of cognition. An experiment of N-back task and a questionnaire of teacher efficacy were conducted in this study to test the effect of the ability of information updating in working memory on the teacher efficacy. A significant difference was found in the reaction time between high teacher efficacy group and low teacher efficacy group. The results showed that teachers who scored higher in the teacher efficacy scale tended to react faster than those who scored lower based on the same accuracy. And the updating information ability could serve as a predictor of teacher efficacy.

  3. Effects of strategy on visual working memory capacity.

    Science.gov (United States)

    Bengson, Jesse J; Luck, Steven J

    2016-02-01

    Substantial evidence suggests that individual differences in estimates of working memory capacity reflect differences in how effectively people use their intrinsic storage capacity. This suggests that estimated capacity could be increased by instructions that encourage more effective encoding strategies. The present study tested this by giving different participants explicit strategy instructions in a change detection task. Compared to a condition in which participants were simply told to do their best, we found that estimated capacity was increased for participants who were instructed to remember the entire visual display, even at set sizes beyond their capacity. However, no increase in estimated capacity was found for a group that was told to focus on a subset of the items in supracapacity arrays. This finding confirms the hypothesis that encoding strategies may influence visual working memory performance, and it is contrary to the hypothesis that the optimal strategy is to filter out any items beyond the storage capacity.

  4. Field-effect transistor memories based on ferroelectric polymers

    Science.gov (United States)

    Zhang, Yujia; Wang, Haiyang; Zhang, Lei; Chen, Xiaomeng; Guo, Yu; Sun, Huabin; Li, Yun

    2017-11-01

    Field-effect transistors based on ferroelectrics have attracted intensive interests, because of their non-volatile data retention, rewritability, and non-destructive read-out. In particular, polymeric materials that possess ferroelectric properties are promising for the fabrications of memory devices with high performance, low cost, and large-area manufacturing, by virtue of their good solubility, low-temperature processability, and good chemical stability. In this review, we discuss the material characteristics of ferroelectric polymers, providing an update on the current development of ferroelectric field-effect transistors (Fe-FETs) in non-volatile memory applications. Program supported partially by the NSFC (Nos. 61574074, 61774080), NSFJS (No. BK20170075), and the Open Partnership Joint Projects of NSFC-JSPS Bilateral Joint Research Projects (No. 61511140098).

  5. Effects of normal aging and Alzheimer's disease on emotional memory.

    Science.gov (United States)

    Kensinger, Elizabeth A; Brierley, Barbara; Medford, Nick; Growdon, John H; Corkin, Suzanne

    2002-06-01

    Recall is typically better for emotional than for neutral stimuli. This enhancement is believed to rely on limbic regions. Memory is also better for neutral stimuli embedded in an emotional context. The neural substrate supporting this effect has not been thoroughly investigated but may include frontal lobe, as well as limbic circuits. Alzheimer's disease (AD) results in atrophy of limbic structures, whereas normal aging relatively spares limbic regions but affects prefrontal areas. The authors hypothesized that AD would reduce all enhancement effects, whereas aging would disproportionately affect enhancement based on emotional context. The results confirmed the authors' hypotheses: Young and older adults, but not AD patients, showed better memory for emotional versus neutral pictures and words. Older adults and AD patients showed no benefit from emotional context, whereas young adults remembered more items embedded in an emotional versus neutral context.

  6. Effects of high-fat diet exposure on learning & memory.

    Science.gov (United States)

    Cordner, Zachary A; Tamashiro, Kellie L K

    2015-12-01

    The associations between consumption of a high-fat or 'Western' diet and metabolic disorders such as obesity, diabetes, and cardiovascular disease have long been recognized and a great deal of evidence now suggests that diets high in fat can also have a profound impact on the brain, behavior, and cognition. Here, we will review the techniques most often used to assess learning and memory in rodent models and discuss findings from studies assessing the cognitive effects of high-fat diet consumption. The review will then consider potential underlying mechanisms in the brain and conclude by reviewing emerging literature suggesting that maternal consumption of a high-fat diet may have effects on the learning and memory of offspring. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Shape-memory effect in Ti-Nb alloys

    International Nuclear Information System (INIS)

    Peradze, T.; Berikashvili, T.; Chelidze, T.; Gorgadze, K.; Bochorishvili, M.; Taktakishvili, M.

    2009-01-01

    The work deals with the investigation of the binary alloy of titanium with niobium and is aimed at demonstrating the functional-mechanical possibilities of Ti-Nb alloys from the viewpoint of their potential application in practice. The shape-memory effect, super elasticity and reactive stress in alloys of Ti-Nb system were studied. It turned out that the work carried out expanded the interval of Nb content in the investigated alloys from 25.9 to 33.1 wt%. The shape recovery made up not less than 90% at the deformation of 6-8%. The reactive stress reached 350-450 MPa. In the alloys under study another (high-temperature) shape-memory effect was found, and the influence of hydrogen and oxygen on the inelastic properties of alloys was studied. (author)

  8. Cognitive control, attention, and the other race effect in memory.

    Science.gov (United States)

    Brown, Thackery I; Uncapher, Melina R; Chow, Tiffany E; Eberhardt, Jennifer L; Wagner, Anthony D

    2017-01-01

    People are better at remembering faces from their own race than other races-a phenomenon with significant societal implications. This Other Race Effect (ORE) in memory could arise from different attentional allocation to, and cognitive control over, same- and other-race faces during encoding. Deeper or more differentiated processing of same-race faces could yield more robust representations of same- vs. other-race faces that could support better recognition memory. Conversely, to the extent that other-race faces may be characterized by lower perceptual expertise, attention and cognitive control may be more important for successful encoding of robust, distinct representations of these stimuli. We tested a mechanistic model in which successful encoding of same- and other-race faces, indexed by subsequent memory performance, is differentially predicted by (a) engagement of frontoparietal networks subserving top-down attention and cognitive control, and (b) interactions between frontoparietal networks and fusiform cortex face processing. European American (EA) and African American (AA) participants underwent fMRI while intentionally encoding EA and AA faces, and ~24 hrs later performed an "old/new" recognition memory task. Univariate analyses revealed greater engagement of frontoparietal top-down attention and cognitive control networks during encoding for same- vs. other-race faces, stemming particularly from a failure to engage the cognitive control network during processing of other-race faces that were subsequently forgotten. Psychophysiological interaction (PPI) analyses further revealed that OREs were characterized by greater functional interaction between medial intraparietal sulcus, a component of the top-down attention network, and fusiform cortex during same- than other-race face encoding. Together, these results suggest that group-based face memory biases at least partially stem from differential allocation of cognitive control and top-down attention during

  9. Experimental Effects of Acute Exercise on Iconic Memory, Short-Term Episodic, and Long-Term Episodic Memory

    Directory of Open Access Journals (Sweden)

    Danielle Yanes

    2018-06-01

    Full Text Available The present experiment evaluated the effects of acute exercise on iconic memory and short- and long-term episodic memory. A two-arm, parallel-group randomized experiment was employed (n = 20 per group; Mage = 21 year. The experimental group engaged in an acute bout of moderate-intensity treadmill exercise for 15 min, while the control group engaged in a seated, time-matched computer task. Afterwards, the participants engaged in a paragraph-level episodic memory task (20 min delay and 24 h delay recall as well as an iconic memory task, which involved 10 trials (at various speeds from 100 ms to 800 ms of recalling letters from a 3 × 3 array matrix. For iconic memory, there was a significant main effect for time (F = 42.9, p < 0.001, η2p = 0.53 and a trend towards a group × time interaction (F = 2.90, p = 0.09, η2p = 0.07, but no main effect for group (F = 0.82, p = 0.37, η2p = 0.02. The experimental group had higher episodic memory scores at both the baseline (19.22 vs. 17.20 and follow-up (18.15 vs. 15.77, but these results were not statistically significant. These findings provide some suggestive evidence hinting towards an iconic memory and episodic benefit from acute exercise engagement.

  10. Postexperience Advertising Effects on Consumer Memory.

    OpenAIRE

    Braun, Kathryn A

    1999-01-01

    Past research suggests that marketing communications create expectations that influence the way consumers subsequently learn from their product experiences. Since postexperience information can also be important and is widespread for established goods and services, it is appropriate to ask about the cognitive effects of these efforts. The postexperience advertising situation is conceptualized here as an instant source-forgetting problem where the language and imagery from the recently present...

  11. The effect of strategic memory training in older adults: who benefits most?

    Science.gov (United States)

    Rosi, Alessia; Del Signore, Federica; Canelli, Elisa; Allegri, Nicola; Bottiroli, Sara; Vecchi, Tomaso; Cavallini, Elena

    2017-12-07

    Previous research has suggested that there is a degree of variability among older adults' response to memory training, such that some individuals benefit more than others. The aim of the present study was to identify the profile of older adults who were likely to benefit most from a strategic memory training program that has previously proved to be effective in improving memory in healthy older adults. In total, 44 older adults (60-83 years) participated in a strategic memory training. We examined memory training benefits by measuring changes in memory practiced (word list learning) and non-practiced tasks (grocery list and associative learning). In addition, a battery of cognitive measures was administered in order to assess crystallized and fluid abilities, short-term memory, working memory, and processing speed. Results confirmed the efficacy of the training in improving performance in both practiced and non-practiced memory tasks. For the practiced memory tasks, results showed that memory baseline performance and crystallized ability predicted training gains. For the non-practiced memory tasks, analyses showed that memory baseline performance was a significant predictor of gain in the grocery list learning task. For the associative learning task, the significant predictors were memory baseline performance, processing speed, and marginally the age. Our results indicate that older adults with a higher baseline memory capacity and with more efficient cognitive resources were those who tended to benefit most from the training. The present study provides new avenues in designing personalized intervention according to the older adults' cognitive profile.

  12. An UV photochromic memory effect in proton-based WO3 electrochromic devices

    International Nuclear Information System (INIS)

    Zhang Yong; Lee, S.-H.; Mascarenhas, A.; Deb, S. K.

    2008-01-01

    We report an UV photochromic memory effect on a standard proton-based WO 3 electrochromic device. It exhibits two memory states, associated with the colored and bleached states of the device, respectively. Such an effect can be used to enhance device performance (increasing the dynamic range), re-energize commercial electrochromic devices, and develop memory devices

  13. An UV photochromic memory effect in proton-based WO3 electrochromic devices

    Science.gov (United States)

    Zhang, Yong; Lee, S.-H.; Mascarenhas, A.; Deb, S. K.

    2008-11-01

    We report an UV photochromic memory effect on a standard proton-based WO3 electrochromic device. It exhibits two memory states, associated with the colored and bleached states of the device, respectively. Such an effect can be used to enhance device performance (increasing the dynamic range), re-energize commercial electrochromic devices, and develop memory devices.

  14. Time-dependent effects of cortisol on the contextualization of emotional memories

    NARCIS (Netherlands)

    van Ast, V.A.; Cornelisse, S.; Meeter, M.; Joëls, M.; Kindt, M.

    2013-01-01

    Background: The inability to store fearful memories into their original encoding context is considered to be an important vulnerability factor for the development of anxiety disorders like posttraumatic stress disorder. Altered memory contextualization most likely involves effects of the stress

  15. Effect of restriction of working memory on reported paranormal belief.

    Science.gov (United States)

    Dudley, R T

    1999-02-01

    56 college students completed Tobacyk's 1988 Revised Paranormal Belief Scale and Watson, Clark, and Tellegen's 1988 Positive and Negative Affect Scale. Experimental group participants, but not control group participants, rehearsed a five-digit number while completing the Paranormal Belief Scale. Analysis showed higher reported paranormal belief for experimental group participants but no differences on the Positive and Negative Affect Scale. Results are discussed in terms of the effect of restriction in working memory on the critical evaluation of paranormal phenomena.

  16. Context-dependent repetition effects on recognition memory.

    OpenAIRE

    Opitz, B

    2010-01-01

    One widely acknowledged way to improve our memory performance is to repeatedly study the to be learned material. One aspect that has received little attention in past research regards the context sensitivity of this repetition effect, that is whether the item is repeated within the same or within different contexts. The predictions of a neuro-computational model (O'Reilly & Norman, 2002) were tested in an experiment requiring participants to study visual objects either once or three times. Cr...

  17. Soft Gravitons & the Memory Effect for Plane Gravitational Waves

    OpenAIRE

    Zhang, P. -M.; Duval, C.; Gibbons, G. W.; Horvathy, P. A.

    2017-01-01

    The "gravitational memory effect" due to an exact plane wave provides us with an elementary description of the diffeomorphisms associated with soft gravitons. It is explained how the presence of the latter may be detected by observing the motion of freely falling particles or other forms of gravitational wave detection. Numerical calculations confirm the relevance of the first, second and third time integrals of the Riemann tensor pointed out earlier. Solutions for various profiles are constr...

  18. Magnetic shape memory effect and highly mobile twin boundaries

    Czech Academy of Sciences Publication Activity Database

    Heczko, Oleg

    2014-01-01

    Roč. 30, č. 13 (2014), s. 1559-1578 ISSN 0267-0836 R&D Projects: GA ČR(CZ) GAP107/11/0391 Institutional support: RVO:68378271 Keywords : magnetic shape memory effect * ferromagnetic martensite * twinning * magnetically induced reorientation * reviews Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.995, year: 2014 http://dx.doi.org/10.1179/1743284714Y.0000000599

  19. Autobiographical Memory Functioning among Abused, Neglected, and Nonmaltreated Children: The Overgeneral Memory Effect

    Science.gov (United States)

    Valentino, Kristin; Toth, Sheree L.; Cicchetti, Dante

    2009-01-01

    Background: This investigation addresses whether there are differences in the form and content of autobiographical memory recall as a function of maltreatment, and examines the roles of self-system functioning and psychopathology in autobiographical memory processes. Methods: Autobiographical memory for positive and negative nontraumatic events…

  20. Levels of processing and picture memory: the physical superiority effect.

    Science.gov (United States)

    Intraub, H; Nicklos, S

    1985-04-01

    Six experiments studied the effect of physical orienting questions (e.g., "Is this angular?") and semantic orienting questions (e.g., "Is this edible?") on memory for unrelated pictures at stimulus durations ranging from 125-2,000 ms. Results ran contrary to the semantic superiority "rule of thumb," which is based primarily on verbal memory experiments. Physical questions were associated with better free recall and cued recall of a diverse set of visual scenes (Experiments 1, 2, and 4). This occurred both when general and highly specific semantic questions were used (Experiments 1 and 2). Similar results were obtained when more simplistic visual stimuli--photographs of single objects--were used (Experiments 5 and 6). As in the case of the semantic superiority effect with words, the physical superiority effect for pictures was eliminated or reversed when the same physical questions were repeated throughout the session (Experiments 4 and 6). Conflicts with results of previous levels of processing experiments with words and nonverbal stimuli (e.g., faces) are explained in terms of the sensory-semantic model (Nelson, Reed, & McEvoy, 1977). Implications for picture memory research and the levels of processing viewpoint are discussed.

  1. Effects of proactive interference on non-verbal working memory.

    Science.gov (United States)

    Cyr, Marilyn; Nee, Derek E; Nelson, Eric; Senger, Thea; Jonides, John; Malapani, Chara

    2017-02-01

    Working memory (WM) is a cognitive system responsible for actively maintaining and processing relevant information and is central to successful cognition. A process critical to WM is the resolution of proactive interference (PI), which involves suppressing memory intrusions from prior memories that are no longer relevant. Most studies that have examined resistance to PI in a process-pure fashion used verbal material. By contrast, studies using non-verbal material are scarce, and it remains unclear whether the effect of PI is domain-general or whether it applies solely to the verbal domain. The aim of the present study was to examine the effect of PI in visual WM using both objects with high and low nameability. Using a Directed-Forgetting paradigm, we varied discriminability between WM items on two dimensions, one verbal (high-nameability vs. low-nameability objects) and one perceptual (colored vs. gray objects). As in previous studies using verbal material, effects of PI were found with object stimuli, even after controlling for verbal labels being used (i.e., low-nameability condition). We also found that the addition of distinctive features (color, verbal label) increased performance in rejecting intrusion probes, most likely through an increase in discriminability between content-context bindings in WM.

  2. Memory effect versus exchange bias for maghemite nanoparticles

    Science.gov (United States)

    Nadeem, K.; Krenn, H.; Szabó, D. V.

    2015-11-01

    We studied the temperature dependence of memory and exchange bias effects and their dependence on each other in maghemite (γ-Fe2O3) nanoparticles by using magnetization studies. Memory effect in zero field cooled process in nanoparticles is a fingerprint of spin-glass behavior which can be due to i) surface disordered spins (surface spin-glass) and/or ii) randomly frozen and interacting nanoparticles core spins (super spin-glass). Temperature region (25-70 K) for measurements has been chosen just below the average blocking temperature (TB=75 K) of the nanoparticles. Memory effect (ME) shows a non-monotonous behavior with temperature. It shows a decreasing trend with decreasing temperature and nearly vanishes below 30 K. However it also decreased again near the blocking temperature of the nanoparticles e.g., 70 K. Exchange bias (EB) in these nanoparticles arises due to core/shell interface interactions. The EB increases sharply below 30 K due to increase in core/shell interactions, while ME starts vanishing below 30 K. We conclude that the core/shell interface interactions or EB have not enhanced the ME but may reduce it in these nanoparticles.

  3. MEMORY MODULATION

    Science.gov (United States)

    Roozendaal, Benno; McGaugh, James L.

    2011-01-01

    Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive evidence from both animal and human research indicates that emotionally significant experiences activate hormonal and brain systems that regulate the consolidation of newly acquired memories. These effects are integrated through noradrenergic activation of the basolateral amygdala which regulates memory consolidation via interactions with many other brain regions involved in consolidating memories of recent experiences. Modulatory systems not only influence neurobiological processes underlying the consolidation of new information, but also affect other mnemonic processes, including memory extinction, memory recall and working memory. In contrast to their enhancing effects on consolidation, adrenal stress hormones impair memory retrieval and working memory. Such effects, as with memory consolidation, require noradrenergic activation of the basolateral amygdala and interactions with other brain regions. PMID:22122145

  4. Effects of music on memory for text.

    Science.gov (United States)

    Purnell-Webb, Patricia; Speelman, Craig P

    2008-06-01

    Previous research has suggested that the use of song can facilitate recall of text. This study examined the effect of repetition of a melody across verses, familiarity with the melody, rhythm, and other structural processing hypotheses to explain this phenomenon. Two experiments were conducted, each with 100 participants recruited from undergraduate Psychology programs (44 men, 156 women, M age = 28.5 yr., SD = 9.4). In Exp. 1, participants learned a four-verse ballad in one of five encoding conditions (familiar melody, unfamiliar melody, unknown rhythm, known rhythm, and spoken). Exp. 2 assessed the effect of familiarity in rhythm-only conditions and of pre-exposure with a previously unfamiliar melody. Measures taken were number of verbatim words recalled and number of lines produced with correct syllabic structure. Analysis indicated that rhythm, with or without musical accompaniment, can facilitate recall of text, suggesting that rhythm may provide a schematic frame to which text can be attached. Similarly, familiarity with the rhythm or melody facilitated recall. Findings are discussed in terms of integration and dual-processing theories.

  5. Demystifying the memory effect: A geometrical approach to understanding speckle correlations

    Science.gov (United States)

    Prunty, Aaron C.; Snieder, Roel K.

    2017-05-01

    The memory effect has seen a surge of research into its fundamental properties and applications since its discovery by Feng et al. [Phys. Rev. Lett. 61, 834 (1988)]. While the wave trajectories for which the memory effect holds are hidden implicitly in the diffusion probability function [Phys. Rev. B 40, 737 (1989)], the physical intuition of why these trajectories satisfy the memory effect has often been masked by the derivation of the memory correlation function itself. In this paper, we explicitly derive the specific trajectories through a random medium for which the memory effect holds. Our approach shows that the memory effect follows from a simple conservation argument, which imposes geometrical constraints on the random trajectories that contribute to the memory effect. We illustrate the time-domain effects of these geometrical constraints with numerical simulations of pulse transmission through a random medium. The results of our derivation and numerical simulations are consistent with established theory and experimentation.

  6. Experimental Effects of Acute Exercise on Iconic Memory, Short-Term Episodic, and Long-Term Episodic Memory.

    Science.gov (United States)

    Yanes, Danielle; Loprinzi, Paul D

    2018-06-11

    The present experiment evaluated the effects of acute exercise on iconic memory and short- and long-term episodic memory. A two-arm, parallel-group randomized experiment was employed ( n = 20 per group; M age = 21 year). The experimental group engaged in an acute bout of moderate-intensity treadmill exercise for 15 min, while the control group engaged in a seated, time-matched computer task. Afterwards, the participants engaged in a paragraph-level episodic memory task (20 min delay and 24 h delay recall) as well as an iconic memory task, which involved 10 trials (at various speeds from 100 ms to 800 ms) of recalling letters from a 3 × 3 array matrix. For iconic memory, there was a significant main effect for time (F = 42.9, p memory scores at both the baseline (19.22 vs. 17.20) and follow-up (18.15 vs. 15.77), but these results were not statistically significant. These findings provide some suggestive evidence hinting towards an iconic memory and episodic benefit from acute exercise engagement.

  7. Overview of radiation effects on emerging non-volatile memory technologies

    Directory of Open Access Journals (Sweden)

    Fetahović Irfan S.

    2017-01-01

    Full Text Available In this paper we give an overview of radiation effects in emergent, non-volatile memory technologies. Investigations into radiation hardness of resistive random access memory, ferroelectric random access memory, magneto-resistive random access memory, and phase change memory are presented in cases where these memory devices were subjected to different types of radiation. The obtained results proved high radiation tolerance of studied devices making them good candidates for application in radiation-intensive environments. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 171007

  8. Individual differences in susceptibility to false memories: The effect of memory specificity.

    Science.gov (United States)

    Dewhurst, Stephen A; Anderson, Rachel J; Berry, Donna M; Garner, Sarah R

    2017-06-25

    Previous research has highlighted the wide individual variability in susceptibility to the false memories produced by 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]. The current study investigated whether susceptibility to false memories is influenced by individual differences in the specificity of autobiographical memory retrieval. Memory specificity was measured using the Sentence Completion for Events from the Past Test (SCEPT) [Raes, F., Hermans, D., Williams, J. M. G., & Eelen, P. (2007). A sentence completion procedure as an alternative to the Autobiographical Memory Test for assessing overgeneral memory in non-clinical populations. Memory, 15, 495-507]. Memory specificity did not correlate with correct recognition, but a specific retrieval style was positively correlated with levels of false recognition. It is proposed that the contextual details that frequently accompany false memories of nonstudied lures are more accessible in individuals with specific retrieval styles.

  9. Do animacy effects persist in memory for context?

    Science.gov (United States)

    Gelin, Margaux; Bonin, Patrick; Méot, Alain; Bugaiska, Aurélia

    2018-04-01

    The adaptive view of human memory assumes that animates (e.g, rabbit) are remembered better than inanimates (e.g. glass) because animates are ultimately more important for fitness than inanimates. Previous studies provided evidence for this view by showing that animates were recalled or recognized better than inanimates, but they did not assess memory for contextual details (e.g., where animates vs inanimates occurred). In this study, we tested recollection of spatial information (Study 1) and temporal information (Study 2) associated with animate versus inanimate words. The findings showed that the two types of contextual information were remembered better when they were related to animates than to inanimates. These findings provide further evidence for an ultimate explanation of animacy effects.

  10. The effects of autobiographical memory and visual perspective on working memory.

    Science.gov (United States)

    Cheng, Zenghu; She, Yugui

    2018-08-01

    The present research aims to explore whether recalling and writing about autobiographical memory from different perspectives (first-person perspective vs. third-person perspective) could affect cognitive function. The participants first performed a working memory task to evaluate their working memory capacity as a baseline and then were instructed to recall (Study 1) or write about (Study 2) personal events (failures vs. successes) from the first-person perspective or the third-person perspective. Finally, they performed the working memory task again. The results suggested that autobiographical memory and perspective influence working memory interactively. When recalling a success, the participants who recalled from the third-person perspective performed better than those who recalled from the first-person perspective on the working memory capacity task; when recalling a failure, the opposite was true.

  11. Sex differences in stress effects on response and spatial memory formation.

    Science.gov (United States)

    Guenzel, Friederike M; Wolf, Oliver T; Schwabe, Lars

    2014-03-01

    Stress and stress hormones are known to affect learning and memory processes. However, although effects of stress on hippocampus-dependent declarative learning and memory are well-documented, relatively little attention has been paid to the impact of stress on striatum-dependent stimulus-response (S-R) learning and memory. Recent evidence indicates that glucocorticoid stress hormones shortly after learning enhance S-R memory consolidation, whereas stress prior to retention testing impairs S-R memory retrieval. Whether stress affects also the acquisition of S-R memories in humans remains unclear. For this reason, we examined here the effects of acute stress on S-R memory formation and contrasted these stress effects with those on hippocampus-dependent spatial memory. Healthy men and women underwent a stressor (socially evaluated cold pressor test, SECPT) or a control manipulation before they completed an S-R task and two spatial learning tasks. Memory was assessed one week later. Our data showed that stress impaired S-R memory performance in men but not in women. Conversely, spatial memory was impaired by stress in women but not in men. These findings provide further evidence that stress may alter learning and memory processes beyond the hippocampus. Moreover, our data underline that participants' sex may play a critical role in the impact of stress on multiple memory systems. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Memory interfering effects of chlordiazepoxide on consummatory successive negative contrast.

    Science.gov (United States)

    Ortega, Leonardo A; Glueck, Amanda C; Daniel, Alan M; Prado-Rivera, Mayerli A; White, Michelle M; Papini, Mauricio R

    2014-01-01

    Long-Evans rats downshifted from 32% to 4% sucrose solution exhibit lower consummatory behavior during downshift trials than rats exposed only to 4% sucrose. In Experiment 1, this effect, called consummatory successive negative contrast (cSNC), was attenuated by administration of the benzodiazepine anxiolytic chlordiazepoxide (CDP, 5mg/kg, ip) before the second downshift trial (Trial 12), but was not affected when CDP was administered before the first downshift trial (Trial 11). In Experiment 2, CDP administered after Trial 11 actually enhanced the cSNC effect on Trial 12. This posttrial effect of CDP was reduced by delayed administration (Experiment 3). This CDP effect was not present in the absence of incentive downshift (Experiments 4-5), or when animals were tested with the preshift incentive (Experiment 6) or after complete recovery from cSNC (Experiment 7). The posttrial CDP effect was observed after an 8-day interval between Trials 11 and 12 (Experiment 8) and when administered after Trial 12, rather than Trial 11 (Experiment 9). Experiment 10 extended the effect to Wistar rats. Because CDP is a memory interfering drug, it was hypothesized that its posttrial administration interferes with the consolidation of the memory of the downshifted incentive, thus prolonging the mismatch between expected (32% sucrose) and obtained (4% sucrose) incentives that leads to the cSNC effect. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. The Effects of Emotion on Episodic Memory for TV Commercials.

    Science.gov (United States)

    Thorson, Esther; Friestad, Marian

    Based on the associational nature of memory, the distinction between episodic and semantic memory, and the notion of memory strength, a model was developed of the role of emotion in the memory of television commercials. The model generated the following hypotheses: (1) emotional commercials will more likely be recalled than nonemotional…

  14. Memory of irrigation effects on hydroclimate and its modeling challenge

    Science.gov (United States)

    Chen, Fei; Xu, Xiaoyu; Barlage, Michael; Rasmussen, Roy; Shen, Shuanghe; Miao, Shiguang; Zhou, Guangsheng

    2018-06-01

    Irrigation modifies land-surface water and energy budgets, and also influences weather and climate. However, current earth-system models, used for weather prediction and climate projection, are still in their infancy stage to consider irrigation effects. This study used long-term data collected from two contrasting (irrigated and rainfed) nearby maize-soybean rotation fields, to study the effects of irrigation memory on local hydroclimate. For a 12 year average, irrigation decreases summer surface-air temperature by less than 1 °C and increases surface humidity by 0.52 g kg‑1. The irrigation cooling effect is more pronounced and longer lasting for maize than for soybean. Irrigation reduces maximum, minimum, and averaged temperature over maize by more than 0.5 °C for the first six days after irrigation, but its temperature effect over soybean is mixed and negligible two or three days after irrigation. Irrigation increases near-surface humidity over maize by about 1 g kg‑1 up to ten days and increases surface humidity over soybean (~ 0.8 g kg‑1) with a similar memory. These differing effects of irrigation memory on temperature and humidity are associated with respective changes in the surface sensible and latent heat fluxes for maize and soybean. These findings highlight great need and challenges for earth-system models to realistically simulate how irrigation effects vary with crop species and with crop growth stages, and to capture complex interactions between agricultural management and water-system components (crop transpiration, precipitation, river, reservoirs, lakes, groundwater, etc.) at various spatial and temporal scales.

  15. Retrospective attention in short-term memory has a lasting effect on long-term memory across age.

    Science.gov (United States)

    Strunk, Jonathan; Morgan, Lauren; Reaves, Sarah; Verhaeghen, Paul; Duarte, Audrey

    2018-04-13

    Declines in both short- and long-term memory are typical of healthy aging. Recent findings suggest that retrodictive attentional cues ("retro-cues") that indicate the location of to-be-probed items in short-term memory (STM) have a lasting impact on long-term memory (LTM) performance in young adults. Whether older adults can also use retro-cues to facilitate both STM and LTM is unknown. Young and older adults performed a visual STM task in which spatially informative retro-cues or non-informative neutral-cues were presented during STM maintenance of real-world objects. We tested participants' memory at both STM and LTM delays for objects that were previously cued with retrodictive or neutral cues during STM order to measure the lasting impact of retrospective attention on LTM. Older adults showed reduced STM and LTM capacity compared to young adults. However, they showed similar magnitude retro-cue memory benefits as young adults at both STM and LTM delays. To the best of our knowledge, this is the first study to investigate whether retro-cues in STM facilitate the encoding of objects into LTM such that they are more likely to be subsequently retrieved by older adults. Our results support the idea that retrospective attention can be an effective means by which older adults can improve their short and long-term memory performance, even in the context of reduced memory capacity.

  16. Parallel and Multivalued Logic by the Two-Dimensional Photon-Echo Response of a Rhodamine–DNA Complex

    Science.gov (United States)

    2015-01-01

    Implementing parallel and multivalued logic operations at the molecular scale has the potential to improve the miniaturization and efficiency of a new generation of nanoscale computing devices. Two-dimensional photon-echo spectroscopy is capable of resolving dynamical pathways on electronic and vibrational molecular states. We experimentally demonstrate the implementation of molecular decision trees, logic operations where all possible values of inputs are processed in parallel and the outputs are read simultaneously, by probing the laser-induced dynamics of populations and coherences in a rhodamine dye mounted on a short DNA duplex. The inputs are provided by the bilinear interactions between the molecule and the laser pulses, and the output values are read from the two-dimensional molecular response at specific frequencies. Our results highlights how ultrafast dynamics between multiple molecular states induced by light–matter interactions can be used as an advantage for performing complex logic operations in parallel, operations that are faster than electrical switching. PMID:25984269

  17. Fourth meeting entitled “Visualization and Processing of Tensors and Higher Order Descriptors for Multi-Valued Data”

    CERN Document Server

    Vilanova, Anna; Burgeth, Bernhard; Visualization and Processing of Tensors and Higher Order Descriptors for Multi-Valued Data

    2014-01-01

    Arising from the fourth Dagstuhl conference entitled Visualization and Processing of Tensors and Higher Order Descriptors for Multi-Valued Data (2011), this book offers a broad and vivid view of current work in this emerging field. Topics covered range from applications of the analysis of tensor fields to research on their mathematical and analytical properties. Part I, Tensor Data Visualization, surveys techniques for visualization of tensors and tensor fields in engineering, discusses the current state of the art and challenges, and examines tensor invariants and glyph design, including an overview of common glyphs. The second Part, Representation and Processing of Higher-order Descriptors, describes a matrix representation of local phase, outlines mathematical morphological operations techniques, extended for use in vector images, and generalizes erosion to the space of diffusion weighted MRI. Part III, Higher Order Tensors and Riemannian-Finsler Geometry, offers powerful mathematical language to model and...

  18. SYNTHESIS AND REDUCED LOGIC GATE REALIZATION OF MULTI-VALUED LOGIC FUNCTIONS USING NEURAL NETWORK DEPLOYMENT ALGORITHM

    Directory of Open Access Journals (Sweden)

    A. K. CHOWDHURY

    2016-02-01

    Full Text Available In this paper an evolutionary technique for synthesizing Multi-Valued Logic (MVL functions using Neural Network Deployment Algorithm (NNDA is presented. The algorithm is combined with back-propagation learning capability and neural MVL operators. This research article is done to observe the anomalistic characteristics of MVL neural operators and their role in synthesis. The advantages of NNDA-MVL algorithm is demonstrated with realization of synthesized many valued functions with lesser MVL operators. The characteristic feature set consists of MVL gate count, network link count, network propagation delay and accuracy achieved in training. In brief, this paper depicts an effort of reduced network size for synthesized MVL functions. Trained MVL operators improve the basic architecture by reducing MIN gate and interlink connection by 52.94% and 23.38% respectively.

  19. Mood-congruent true and false memory: effects of depression.

    Science.gov (United States)

    Howe, Mark L; Malone, Catherine

    2011-02-01

    The Deese/Roediger-McDermott paradigm was used to investigate the effect of depression on true and false recognition. In this experiment true and false recognition was examined across positive, neutral, negative, and depression-relevant lists for individuals with and without a diagnosis of major depressive disorder. Results showed that participants with major depressive disorder falsely recognised significantly more depression-relevant words than non-depressed controls. These findings also parallel recent research using recall instead of recognition and show that there are clear mood congruence effects for depression on false memory performance. © 2011 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business

  20. Action Control: Independent Effects of Memory and Monocular Viewing on Reaching Accuracy

    Science.gov (United States)

    Westwood, D.A.; Robertson, C.; Heath, M.

    2005-01-01

    Evidence suggests that perceptual networks in the ventral visual pathway are necessary for action control when targets are viewed with only one eye, or when the target must be stored in memory. We tested whether memory-linked (i.e., open-loop versus memory-guided actions) and monocular-linked effects (i.e., binocular versus monocular actions) on…

  1. The Effect of Rehearsal Training on Working Memory Span of Children with Fetal Alcohol Spectrum Disorder

    Science.gov (United States)

    Loomes, Carly; Rasmussen, Carmen; Pei, Jacqueline; Manji, Shazeen; Andrew, Gail

    2008-01-01

    A key area of weakness in individuals with fetal alcohol spectrum disorder (FASD) is working memory, thus the goal of this study was to determine whether teaching children (aged 4-11) with FASD verbal rehearsal would increase their memory. Rehearsal training has been effective in other populations with working memory difficulties, so we…

  2. Working Memory Capacity and Reading Skill Moderate the Effectiveness of Strategy Training in Learning from Hypertext

    Science.gov (United States)

    Naumann, Johannes; Richter, Tobias; Christmann, Ursula; Groeben, Norbert

    2008-01-01

    Cognitive and metacognitive strategies are particularly important for learning with hypertext. The effectiveness of strategy training, however, depends on available working memory resources. Thus, especially learners high on working memory capacity can profit from strategy training, while learners low on working memory capacity might easily be…

  3. Computer Use and Its Effect on the Memory Process in Young and Adults

    Science.gov (United States)

    Alliprandini, Paula Mariza Zedu; Straub, Sandra Luzia Wrobel; Brugnera, Elisangela; de Oliveira, Tânia Pitombo; Souza, Isabela Augusta Andrade

    2013-01-01

    This work investigates the effect of computer use in the memory process in young and adults under the Perceptual and Memory experimental conditions. The memory condition involved the phases acquisition of information and recovery, on time intervals (2 min, 24 hours and 1 week) on situations of pre and post-test (before and after the participants…

  4. Opposite Effects of Cortisol on Consolidation of Temporal Sequence Memory during Waking and Sleep

    Science.gov (United States)

    Wilhelm, Ines; Wagner, Ullrich; Born, Jan

    2011-01-01

    Memory functions involve three stages: encoding, consolidation, and retrieval. Modulating effects of glucocorticoids (GCs) have been consistently observed for declarative memory with GCs enhancing encoding and impairing retrieval, but surprisingly, little is known on how GCs affect memory consolidation. Studies in rats suggest a beneficial effect…

  5. Effects of 5-HT on memory and the hippocampus: model and data.

    NARCIS (Netherlands)

    Meeter, M.; Talamini, L.M.; Schmitt, J.A.J.; Riedel, W.J.

    2006-01-01

    5-Hydroxytryptamine (5-HT) transmission has been implicated in memory and in depression. Both 5-HT depletion and specific 5-HT agonists lower memory performance, while depression is also associated with memory deficits. The precise neuropharmacology and neural mechanisms underlying these effects are

  6. The effect of desflurane on postoperative olfactory memory.

    Science.gov (United States)

    Yildiz, I; Bayır, H; Saglam, I; Sereflican, M; Bilgi, M; Yurttas, V; Demirhan, A; Tekelioglu, U Y; Kocoglu, H

    2016-05-01

    In this study, we investigated the effects of desflurane 6%, on olfactory memory. This is a prospective clinical study performed with 40 patients aged 18-60 who had elective surgery and American Society of Anesthesiologists (ASA) physical status I-III. The Brief Smell Identification Test (BSIT) was used for evaluating patients' olfactory memories before and after the surgery. Patients received standard general anesthesia protocol and routine monitoring. For induction, 1.5 mg/kg of fentanyl, 2 mg/kg of propofol, and 0.5 mg/kg of rocuronium bromide were administered. Anesthesia was maintained with the inhalational of anesthetic desflurane (6%). The scores are recorded 30 minutes before the surgery and when the Aldrete Recovery Score reached 10 in the postoperative period. Preoperative and postoperative results were compared and p-values 0.05). We have observed for the first time in the literature that general anesthesia using desflurane (6%) did not affect short-term olfactory memory. Further studies will be necessary to confirm our findings with larger sample size.

  7. Shape memory effects in a uranium + 14 at. % niobium alloy

    International Nuclear Information System (INIS)

    Vandermeer, R.A.; Ogle, J.C.; Snyder, W.B. Jr.

    1978-01-01

    There is a class of alloys that, on cooling from elevated temperatures, experience a martensitic phase change. Some of these, when stressed in the martensitic state to an apparently plastic strain, recover their predeformed shape simply by heating. This striking shape recovery is known as the ''shape memory effect'' (SME). Up to a certain limiting strain, epsilon/sub L/, 100% shape recovery may be accomplished. This memory phenomenon seems to be attributable to the thermoelastic nature of and deformational modes associated with the phase transformation in the alloy. Thus, shape recovery results when a stress-biased martensite undergoes a heat-activated reversion back to the parent phase from which it originated. There are uranium alloys that demonstrate SME-behavior. Uranium-rich, uranium--niobium alloys were the first to be documented; New experimental observations of SME in a polycrystalline uranium--niobium alloy are presented. This alloy can exhibit a two-way memory under cetain circumstances. Additional indirect evidence is presented suggesting that the characteristics of the accompanying phase transformation in this alloy meet the criteria or ''selection rules'' deemed essential for SME

  8. Thermal effects in magnetoelectric memories with stress-mediated switching

    International Nuclear Information System (INIS)

    Giordano, S; Dusch, Y; Tiercelin, N; Pernod, P; Preobrazhensky, V

    2013-01-01

    Heterostructures with magneto-electro-elastic coupling (e.g. multiferroics) are of paramount importance for developing new sensors, actuators and memories. With the progressive miniaturization of these systems it is necessary to take into account possible thermal effects, which may influence the normal operating regime. As a paradigmatic example we consider a recently introduced non-volatile memory element composed of a magnetostrictive nanoparticle embedded in a piezoelectric matrix. The distributions of the physical fields in this matrix/inclusion configuration are determined by means of the Eshelby theory, the magnetization dynamics is studied through the Landau–Lifshitz–Gilbert formalism, and the statistical mechanics is introduced with the Langevin and Fokker–Planck methodologies. As result of the combination of such techniques we determine the switching time between the states of the memory, the error probability and the energy dissipation of the writing process. They depend on the ratio k B T/v where T is the absolute temperature and v is the volume of the magnetoelastic particle. (paper)

  9. Glucoregulatory and order effects on verbal episodic memory in healthy adolescents after oral glucose administration

    OpenAIRE

    Smith, Michael; Foster, Jonathan

    2008-01-01

    The ingestion of oral glucose has been observed to facilitate memory performance in both elderly individuals and in young adults. However, fewer studies have investigated the effect of glucose on memory in children or adolescents. In the present study, the ingestion of a glucose laden drink was observed to enhance verbal episodic memory performance in healthy adolescents under conditions of divided attention, relative to a placebo drink. Further analyses found that this glucose memory facilit...

  10. Glucocorticoid effects on object recognition memory require training-associated emotional arousal

    OpenAIRE

    Okuda, Shoki; Roozendaal, Benno; McGaugh, James L.

    2004-01-01

    Considerable evidence implicates glucocorticoid hormones in the regulation of memory consolidation and memory retrieval. The present experiments investigated whether the influence of these hormones on memory depends on the level of emotional arousal induced by the training experience. We investigated this issue in male Sprague–Dawley rats by examining the effects of immediate posttraining systemic injections of the glucocorticoid corticosterone on object recognition memory under two condition...

  11. A Study of Memory Effects in a Chess Database.

    Science.gov (United States)

    Schaigorodsky, Ana L; Perotti, Juan I; Billoni, Orlando V

    2016-01-01

    A series of recent works studying a database of chronologically sorted chess games-containing 1.4 million games played by humans between 1998 and 2007- have shown that the popularity distribution of chess game-lines follows a Zipf's law, and that time series inferred from the sequences of those game-lines exhibit long-range memory effects. The presence of Zipf's law together with long-range memory effects was observed in several systems, however, the simultaneous emergence of these two phenomena were always studied separately up to now. In this work, by making use of a variant of the Yule-Simon preferential growth model, introduced by Cattuto et al., we provide an explanation for the simultaneous emergence of Zipf's law and long-range correlations memory effects in a chess database. We find that Cattuto's Model (CM) is able to reproduce both, Zipf's law and the long-range correlations, including size-dependent scaling of the Hurst exponent for the corresponding time series. CM allows an explanation for the simultaneous emergence of these two phenomena via a preferential growth dynamics, including a memory kernel, in the popularity distribution of chess game-lines. This mechanism results in an aging process in the chess game-line choice as the database grows. Moreover, we find burstiness in the activity of subsets of the most active players, although the aggregated activity of the pool of players displays inter-event times without burstiness. We show that CM is not able to produce time series with bursty behavior providing evidence that burstiness is not required for the explanation of the long-range correlation effects in the chess database. Our results provide further evidence favoring the hypothesis that long-range correlations effects are a consequence of the aging of game-lines and not burstiness, and shed light on the mechanism that operates in the simultaneous emergence of Zipf's law and long-range correlations in a community of chess players.

  12. A Study of Memory Effects in a Chess Database.

    Directory of Open Access Journals (Sweden)

    Ana L Schaigorodsky

    Full Text Available A series of recent works studying a database of chronologically sorted chess games-containing 1.4 million games played by humans between 1998 and 2007- have shown that the popularity distribution of chess game-lines follows a Zipf's law, and that time series inferred from the sequences of those game-lines exhibit long-range memory effects. The presence of Zipf's law together with long-range memory effects was observed in several systems, however, the simultaneous emergence of these two phenomena were always studied separately up to now. In this work, by making use of a variant of the Yule-Simon preferential growth model, introduced by Cattuto et al., we provide an explanation for the simultaneous emergence of Zipf's law and long-range correlations memory effects in a chess database. We find that Cattuto's Model (CM is able to reproduce both, Zipf's law and the long-range correlations, including size-dependent scaling of the Hurst exponent for the corresponding time series. CM allows an explanation for the simultaneous emergence of these two phenomena via a preferential growth dynamics, including a memory kernel, in the popularity distribution of chess game-lines. This mechanism results in an aging process in the chess game-line choice as the database grows. Moreover, we find burstiness in the activity of subsets of the most active players, although the aggregated activity of the pool of players displays inter-event times without burstiness. We show that CM is not able to produce time series with bursty behavior providing evidence that burstiness is not required for the explanation of the long-range correlation effects in the chess database. Our results provide further evidence favoring the hypothesis that long-range correlations effects are a consequence of the aging of game-lines and not burstiness, and shed light on the mechanism that operates in the simultaneous emergence of Zipf's law and long-range correlations in a community of chess

  13. Factors influencing shape memory effect and phase transformation behaviour of Fe-Mn-Si based shape memory alloys

    International Nuclear Information System (INIS)

    Li, H.; Dunne, D.; Kennon, N.

    1999-01-01

    The objective of this research work was to investigate the factors influencing the shape memory effect and phase transformation behaviour of three Fe-Mn-Si based shape memory alloys: Fe-28Mn-6Si, Fe-13Mn-5Si-10Cr-6Ni and Fe-20Mn-6Si-7Cr-1Cu. The research results show that the shape memory capacity of Fe-Mn-Si based shape memory alloys varies with annealing temperature, and this effect can be explained in terms of the effect of annealing on γ ε transformation. The nature and concentration of defects in austenite are strongly affected by annealing conditions. A high annealing temperature results in a low density of stacking faults, leading to a low nucleation rate during stress induced γ→ε transformation. The growth of ε martensite plates is favoured rather than the formation of new ε martensite plates. Coarse martensite plates produce high local transformation strains which can be accommodated by local slip deformation, leading to a reduction in the reversibility of the martensitic transformation and to a degradation of the shape memory effect. Annealing at low temperatures (≤673 K) for reasonable times does not eliminate complex defects (dislocation jogs, kinks and vacancy clusters) created by hot and cold working strains. These defects can retard the movement and rearrangement of Shockley partial dislocations, i.e. suppress γ→ε transformation, also leading to a degradation of shape memory effect. Annealing at about 873 K was found to be optimal to form the dislocation structures which are favourable for stress induced martensitic transformation, thus resulting in the best shape memory behaviour. (orig.)

  14. The effects of heterogeneities on memory-dependent diffusion

    Science.gov (United States)

    Adib, Farhad; Neogi, P.

    1993-07-01

    Case II diffusion is often seen in glassy polymers, where the mass uptake in sorption is proportional to time t instead of sqrt{t}. A memory dependent diffusion is needed to explain such effects, where the relaxation function used to describe the memory effect has a characteristic time. The ratio of this time to the overall diffusion times is the diffusional Deborah number. Simple models show that case II results when the Deborah number is around one, that is, when the two time scales are comparable. Under investigation are the possible effects of the fact that the glassy polymers are heterogeneous over molecular scales. The averaging form given by DiMarzio and Sanchez has been used to obtain the averaged response. The calculated dynamics of sorption show that whereas case II is still observed, the long term tails change dramatically from the oscillatory to torpid, to chaotic, which are all observed in the experiments. The Deborah number defined here in a self-consistent manner collapses in those cases, but causes no other ill-effects.

  15. Approximation of a Common Element of the Fixed Point Sets of Multivalued Strictly Pseudocontractive-Type Mappings and the Set of Solutions of an Equilibrium Problem in Hilbert Spaces

    Directory of Open Access Journals (Sweden)

    F. O. Isiogugu

    2016-01-01

    Full Text Available The strong convergence of a hybrid algorithm to a common element of the fixed point sets of multivalued strictly pseudocontractive-type mappings and the set of solutions of an equilibrium problem in Hilbert spaces is obtained using a strict fixed point set condition. The obtained results improve, complement, and extend the results on multivalued and single-valued mappings in the contemporary literature.

  16. Kovacs-Like Memory Effect in Driven Granular Gases

    Science.gov (United States)

    Prados, A.; Trizac, E.

    2014-05-01

    While memory effects have been reported for dense enough disordered systems such as glasses, we show here by a combination of analytical and simulation techniques that they are also intrinsic to the dynamics of dilute granular gases. By means of a certain driving protocol, we prepare the gas in a state where the granular temperature T coincides with its long time limit. However, T does not subsequently remain constant but exhibits a nonmonotonic evolution before reaching its nonequilibrium steady value. The corresponding so-called Kovacs hump displays a normal behavior for weak dissipation (as observed in molecular systems) but is reversed under strong dissipation, where it, thus, becomes anomalous.

  17. Stereotype Threat Effects on Older Adults' Episodic and Working Memory: A Meta-Analysis.

    Science.gov (United States)

    Armstrong, Bonnie; Gallant, Sara N; Li, Lingqian; Patel, Khushi; Wong, Brenda I

    2017-08-01

    Prior research has shown that exposure to negative age-based stereotype threat (ST) can undermine older adults' memory performance. The objective of the current meta-analysis was to examine the reliability and magnitude of ST effects on older adults' episodic and working memory performance-two forms of memory that typically show the greatest age-related declines. In addition, we examined potential moderators of age-based ST including type of ST manipulation, type and timing of memory task, participant age and education level. A total of 23 samples for episodic memory and 15 samples for working memory were derived from 19 published and 4 unpublished articles and analyzed in two separate meta-analyses. Analyses revealed a reliable effect of ST on both older adults' episodic (d = 0.373) and working memory performance (d = 0.253). Interestingly, the age-based ST effect was only significant when blatant ST manipulations were used with episodic memory tasks or when subtle ST manipulations were used with working memory tasks. Moreover, within episodic memory, the ST effect only reached significance for recall but not cued-recall or recognition performance, and for immediate but not delayed tests of memory. Neither age nor level of education moderated the association between ST and older adults' memory performance. These results highlight the vulnerability of both older adults' episodic and working memory performance to age-based ST. When measuring older adults' memory performance in a research context, we must therefore be wary of exposing participants to common stereotypes about aging and memory. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Synesthesia and Memory: Color Congruency, Von Restorff, and False Memory Effects

    Science.gov (United States)

    Radvansky, Gabriel A.; Gibson, Bradley S.; McNerney, M. Windy

    2011-01-01

    In the current study, we explored the influence of synesthesia on memory for word lists. We tested 10 grapheme-color synesthetes who reported an experience of color when reading letters or words. We replicated a previous finding that memory is compromised when synesthetic color is incongruent with perceptual color. Beyond this, we found that,…

  19. Divided Attention Can Enhance Memory Encoding: The Attentional Boost Effect in Implicit Memory

    Science.gov (United States)

    Spataro, Pietro; Mulligan, Neil W.; Rossi-Arnaud, Clelia

    2013-01-01

    Distraction during encoding has long been known to disrupt later memory performance. Contrary to this long-standing result, we show that detecting an infrequent target in a dual-task paradigm actually improves memory encoding for a concurrently presented word, above and beyond the performance reached in the full-attention condition. This absolute…

  20. The Sensory Nature of Episodic Memory: Sensory Priming Effects Due to Memory Trace Activation

    Science.gov (United States)

    Brunel, Lionel; Labeye, Elodie; Lesourd, Mathieu; Versace, Remy

    2009-01-01

    The aim of this study was to provide evidence that memory and perceptual processing are underpinned by the same mechanisms. Specifically, the authors conducted 3 experiments that emphasized the sensory aspect of memory traces. They examined their predictions with a short-term priming paradigm based on 2 distinct phases: a learning phase consisting…

  1. "I'll Remember This!" Effects of Emotionality on Memory Predictions versus Memory Performance

    Science.gov (United States)

    Zimmerman, Carissa A.; Kelley, Colleen M.

    2010-01-01

    Emotionality is a key component of subjective experience that influences memory. We tested how the emotionality of words affects memory monitoring, specifically, judgments of learning, in both cued recall and free recall paradigms. In both tasks, people predicted that positive and negative emotional words would be recalled better than neutral…

  2. Effects of a Memory Training Program in Older People with Severe Memory Loss

    Science.gov (United States)

    Mateos, Pedro M.; Valentin, Alberto; González-Tablas, Maria del Mar; Espadas, Verónica; Vera, Juan L.; Jorge, Inmaculada García

    2016-01-01

    Strategies based memory training programs are widely used to enhance the cognitive abilities of the elderly. Participants in these training programs are usually people whose mental abilities remain intact. Occasionally, people with cognitive impairment also participate. The aim of this study was to test if memory training designed specifically for…

  3. The effect of word concreteness on recognition memory.

    Science.gov (United States)

    Fliessbach, K; Weis, S; Klaver, P; Elger, C E; Weber, B

    2006-09-01

    Concrete words that are readily imagined are better remembered than abstract words. Theoretical explanations for this effect either claim a dual coding of concrete words in the form of both a verbal and a sensory code (dual-coding theory), or a more accessible semantic network for concrete words than for abstract words (context-availability theory). However, the neural mechanisms of improved memory for concrete versus abstract words are poorly understood. Here, we investigated the processing of concrete and abstract words during encoding and retrieval in a recognition memory task using event-related functional magnetic resonance imaging (fMRI). As predicted, memory performance was significantly better for concrete words than for abstract words. Abstract words elicited stronger activations of the left inferior frontal cortex both during encoding and recognition than did concrete words. Stronger activation of this area was also associated with successful encoding for both abstract and concrete words. Concrete words elicited stronger activations bilaterally in the posterior inferior parietal lobe during recognition. The left parietal activation was associated with correct identification of old stimuli. The anterior precuneus, left cerebellar hemisphere and the posterior and anterior cingulate cortex showed activations both for successful recognition of concrete words and for online processing of concrete words during encoding. Additionally, we observed a correlation across subjects between brain activity in the left anterior fusiform gyrus and hippocampus during recognition of learned words and the strength of the concreteness effect. These findings support the idea of specific brain processes for concrete words, which are reactivated during successful recognition.

  4. Effects of Sleep on Word Pair Memory in Children – Separating Item and Source Memory Aspects

    Directory of Open Access Journals (Sweden)

    Jing-Yi Wang

    2017-09-01

    Full Text Available Word paired-associate learning is a well-established task to demonstrate sleep-dependent memory consolidation in adults as well as children. Sleep has also been proposed to benefit episodic features of memory, i.e., a memory for an event (item bound into the spatiotemporal context it has been experienced in (source. We aimed to explore if sleep enhances word pair memory in children by strengthening the episodic features of the memory, in particular. Sixty-one children (8–12 years studied two lists of word pairs with 1 h in between. Retrieval testing comprised cued recall of the target word of each word pair (item memory and recalling in which list the word pair had appeared in (source memory. Retrieval was tested either after 1 h (short retention interval or after 11 h, with this long retention interval covering either nocturnal sleep or daytime wakefulness. Compared with the wake interval, sleep enhanced separate recall of both word pairs and the lists per se, while recall of the combination of the word pair and the list it had appeared in remained unaffected by sleep. An additional comparison with adult controls (n = 37 suggested that item-source bound memory (combined recall of word pair and list is generally diminished in children. Our results argue against the view that the sleep-induced enhancement in paired-associate learning in children is a consequence of sleep specifically enhancing the episodic features of the memory representation. On the contrary, sleep in children might strengthen item and source representations in isolation, while leaving the episodic memory representations (item-source binding unaffected.

  5. Brain-behavior relationships in source memory: Effects of age and memory ability.

    Science.gov (United States)

    Meusel, Liesel-Ann; Grady, Cheryl L; Ebert, Patricia E; Anderson, Nicole D

    2017-06-01

    There is considerable evidence for age-related decrements in source memory retrieval, but the literature on the neural correlates of these impairments is mixed. In this study, we used functional magnetic resonance imaging to examine source memory retrieval-related brain activity, and the monotonic relationship between retrieval-related brain activity and source memory accuracy, as a function of both healthy aging (younger vs older) and memory ability within the older adult group (Hi-Old vs Lo-Old). Participants studied lists of word pairs, half visually, half aurally; these were re-presented visually in a scanned test phase and participants indicated if the pair was 'seen' or 'heard' in the study phase. The Lo-Old, but not the Hi-Old, showed source memory performance decrements compared to the Young. During retrieval of source memories, younger and older adults engaged lateral and medial prefrontal cortex (PFC) and medial posterior parietal (and occipital) cortices. The groups differed in how brain activity related to source memory accuracy in dorsal anterior cingulate cortex, precuneus/cuneus, and the inferior parietal cortex; in each of these areas, greater activity was associated with poorer accuracy in the Young, but with higher accuracy in the Hi-Old (anterior cingulate and precuneus/cuneus) and Lo-Old (inferior parietal lobe). Follow-up pairwise group interaction analyses revealed that greater activity in right parahippocampal gyrus was associated with better source memory in the Hi-Old, but not in the Lo-Old. We conclude that older adults recruit additional brain regions to compensate for age-related decline in source memory, but the specific regions involved differ depending on their episodic memory ability. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. How autobiographical memories can support episodic recall: transfer and maintenance effect of memory training with old-old low-autonomy adults.

    Science.gov (United States)

    Carretti, Barbara; Facchini, Giulia; Nicolini, Chiara

    2011-02-01

    A large body of research has demonstrated that, although specific memory activities can enhance the memory performance of healthy older adults, the extent of the increment is negatively associated with age. Conversely, few studies have examined the case of healthy elderly people not living alone. This study has two mains goals: to understand whether older adults with limited autonomy can benefit from activities devoted to increasing their episodic memory performance, and to test the efficacy of a memory training program based on autobiographical memories, in terms of transfer and maintenance effect. We postulated that being able to rely on stable autobiographical memories (intrinsically associated with emotions) would be a valuable memory aid. Memory training was given to healthy older adults (aged 75-85) living in a retirement home. Two programs were compared: in the first, participants were primed to recall autobiographical memories around certain themes, and then to complete a set of episodic memory tasks (experimental group); in the second, participants were only given the episodic tasks (control group). Both groups improved their performance from pre- to post-test. However, the experimental group reported a greater feeling of well-being after the training, and maintained the training gains relating to episodic performance after three months. Our findings suggest that specific memory activities are beneficial to elderly people living in a retirement home context. In addition, training based on reactivation of autobiographical memories is shown to produce a long-lasting effect on memory performance.

  7. Glucose effects on long-term memory performance : duration and domain specificity.

    OpenAIRE

    Owen, Laura; Finnegan, Yvonne; Hu, Henglong; Scholey, Andrew B.; Sünram-Lea, Sandra I.

    2010-01-01

    Rational; Previous research has suggested that long term- verbal declarative memory is particularly sensitive to enhancement by glucose loading, however investigation of glucose effects on certain memory domains has hitherto been neglected. Therefore domain specificity of glucose effects merits further elucidation. Objectives; The aim of the present research was to provide a more comprehensive investigation of the possible effects of glucose administration on different aspects of memory by i)...

  8. Effects of Divided Attention at Retrieval on Conceptual Implicit Memory

    OpenAIRE

    Prull, Matthew W.; Lawless, Courtney; Marshall, Helen M.; Sherman, Annabella T. K.

    2016-01-01

    This study investigated whether conceptual implicit memory is sensitive to process-specific interference at the time of retrieval. Participants performed the implicit memory test of category exemplar generation (Experiments 1 and 3), or the matched explicit memory test of category-cued recall (Experiment 2), both of which are conceptually-driven memory tasks, under one of two divided attention (DA) conditions in which participants simultaneously performed a distracting task. The distracting...

  9. Effects of sleep on memory for conditioned fear and fear extinction

    Science.gov (United States)

    Pace-Schott, Edward F.; Germain, Anne; Milad, Mohammed R.

    2015-01-01

    Learning and memory for extinction of conditioned fear is a basic mammalian mechanism for regulating negative emotion. Sleep promotes both the consolidation of memory and the regulation of emotion. Sleep can influence consolidation and modification of memories associated with both fear and its extinction. After brief overviews of the behavior and neural circuitry associated with fear conditioning, extinction learning and extinction memory in the rodent and human, interactions of sleep with these processes will be examined. Animal and human studies suggest that sleep can serve to consolidate both fear and extinction memory. In humans, sleep also promotes generalization of extinction memory. Time-of-day effects on extinction learning and generalization are also seen. REM may be a sleep stage of particular importance for the consolidation of both fear and extinction memory as evidenced by selective REM deprivation experiments. REM sleep is accompanied by selective activation of the same limbic structures implicated in the learning and memory of fear and extinction. Preliminary evidence also suggests extinction learning can take place during slow wave sleep. Study of low-level processes such as conditioning, extinction and habituation may allow sleep effects on emotional memory to be identified and inform study of sleep’s effects on more complex, emotionally salient declarative memories. Anxiety disorders are marked by impairments of both sleep and extinction memory. Improving sleep quality may ameliorate anxiety disorders by strengthening naturally acquired extinction. Strategically timed sleep may be used to enhance treatment of anxiety by strengthening therapeutic extinction learned via exposure therapy. PMID:25894546

  10. Spatial working memory in aging and mild cognitive impairment: effects of task load and contextual cueing.

    Science.gov (United States)

    Kessels, Roy P C; Meulenbroek, Olga; Fernández, Guillén; Olde Rikkert, Marcel G M

    2010-09-01

    Mild Cognitive Impairment (MCI) is characterized by episodic memory deficits, while aspects of working memory may also be implicated, but studies into this latter domain are scarce and results are inconclusive. Using a computerized search paradigm, this study compares 25 young adults, 25 typically aging older adults and 15 amnestic MCI patients as to their working-memory capacities for object-location information and potential differential effects of memory load and additional context cues. An age-related deficit in visuospatial working-memory maintenance was found that became more pronounced with increasing task demands. The MCI group additionally showed reduced maintenance of bound information, i.e., object-location associations, again especially at elevated memory load. No effects of contextual cueing were found. The current findings indicate that working memory should be considered when screening patients for suspected MCI and monitoring its progression.

  11. The effects of eye movements on emotional memories: using an objective measure of cognitive load.

    Science.gov (United States)

    van Veen, Suzanne C; Engelhard, Iris M; van den Hout, Marcel A

    2016-01-01

    Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder. The working memory (WM) theory explains its efficacy: recall of an aversive memory and making eye movements (EM) both produce cognitive load, and competition for the limited WM resources reduces the memory's vividness and emotionality. The present study tested several predictions from WM theory. We hypothesized that 1) recall of an aversive autobiographical memory loads WM compared to no recall, and 2) recall with EM reduces the vividness, emotionality, and cognitive load of recalling the memory more than only recall or only cognitive effort (i.e., recall of an irrelevant memory with EM). Undergraduates (N=108) were randomly assigned to one of three conditions: 1) recall relevant memory with EM, 2) recall relevant memory without EM, and 3) recall irrelevant memory with EM. We used a random interval repetition task to measure the cognitive load of recalling the memory. Participants responded to randomly administered beeps, with or without recalling the memory. The degree to which participants slow down during recall provides an index of cognitive load. We measured the cognitive load and self-reported vividness and emotionality before, halfway through (8×24 s), and after (16×24 s) the intervention. Reaction times slowed down during memory recall compared to no recall. The recall relevant with EM condition showed a larger decrease in self-reported vividness and emotionality than the control conditions. The cognitive load of recalling the memory also decreased in this condition but not consistently more than in the control conditions. Recall of an aversive memory loads WM, but drops in vividness and emotionality do not immediately reduce the cognitive load of recalling the memory. More research is needed to find objective measures that could capture changes in the quality of the memory.

  12. The effects of eye movements on emotional memories: using an objective measure of cognitive load

    Directory of Open Access Journals (Sweden)

    Suzanne C. van Veen

    2016-07-01

    Full Text Available Background: Eye movement desensitization and reprocessing (EMDR is an effective treatment for posttraumatic stress disorder. The working memory (WM theory explains its efficacy: recall of an aversive memory and making eye movements (EM both produce cognitive load, and competition for the limited WM resources reduces the memory's vividness and emotionality. The present study tested several predictions from WM theory. Objective: We hypothesized that 1 recall of an aversive autobiographical memory loads WM compared to no recall, and 2 recall with EM reduces the vividness, emotionality, and cognitive load of recalling the memory more than only recall or only cognitive effort (i.e., recall of an irrelevant memory with EM. Method: Undergraduates (N=108 were randomly assigned to one of three conditions: 1 recall relevant memory with EM, 2 recall relevant memory without EM, and 3 recall irrelevant memory with EM. We used a random interval repetition task to measure the cognitive load of recalling the memory. Participants responded to randomly administered beeps, with or without recalling the memory. The degree to which participants slow down during recall provides an index of cognitive load. We measured the cognitive load and self-reported vividness and emotionality before, halfway through (8×24 s, and after (16×24 s the intervention. Results: Reaction times slowed down during memory recall compared to no recall. The recall relevant with EM condition showed a larger decrease in self-reported vividness and emotionality than the control conditions. The cognitive load of recalling the memory also decreased in this condition but not consistently more than in the control conditions. Conclusions: Recall of an aversive memory loads WM, but drops in vividness and emotionality do not immediately reduce the cognitive load of recalling the memory. More research is needed to find objective measures that could capture changes in the quality of the memory.

  13. A dual memory theory of the testing effect.

    Science.gov (United States)

    Rickard, Timothy C; Pan, Steven C

    2017-06-05

    A new theoretical framework for the testing effect-the finding that retrieval practice is usually more effective for learning than are other strategies-is proposed, the empirically supported tenet of which is that separate memories form as a consequence of study and test events. A simplest case quantitative model is derived from that framework for the case of cued recall. With no free parameters, that model predicts both proportion correct in the test condition and the magnitude of the testing effect across 10 experiments conducted in our laboratory, experiments that varied with respect to material type, retention interval, and performance in the restudy condition. The model also provides the first quantitative accounts of (a) the testing effect as a function of performance in the restudy condition, (b) the upper bound magnitude of the testing effect, (c) the effect of correct answer feedback, (d) the testing effect as a function of retention interval for the cases of feedback and no feedback, and (e) the effect of prior learning method on subsequent learning through testing. Candidate accounts of several other core phenomena in the literature, including test-potentiated learning, recognition versus cued recall training effects, cued versus free recall final test effects, and other select transfer effects, are also proposed. Future prospects and relations to other theories are discussed.

  14. The Effect of Vocalization on Melodic Memory Conservation.

    Science.gov (United States)

    Pembrook, Randall G.

    1987-01-01

    Reports on a study which reinforces prior findings on melodic memory that show a majority of students do not sing accurately enough after only one hearing of a melody to benefit from vocalization memory techniques. Questions whether vocalization can be a memory reinforcer in melodies that are shorter and simpler than those used in this research.…

  15. Perceptual effects on remembering: recollective processes in picture recognition memory.

    Science.gov (United States)

    Rajaram, S

    1996-03-01

    In 3 experiments, the effects of perceptual manipulations on recollective experience were tested. In Experiment 1, a picture-superiority effect was obtained for overall recognition and Remember judgements in a picture recognition task. In Experiment 2, size changes of pictorial stimuli across study and test reduced recognition memory and Remember judgements. In Experiment 3, deleterious effects of changes in left-right orientation of pictorial stimuli across study and test were obtained for Remember judgements. An alternate framework that emphasizes a distinctiveness-fluency processing distinction is proposed to account for these findings because they cannot easily be accommodated within the existing account of differences in conceptual and perceptual processing for the 2 categories of recollective experience: Remembering and Knowing, respectively (J. M. Gardiner, 1988; S. Rajaram, 1993).

  16. Individual differences in the gesture effect on working memory.

    Science.gov (United States)

    Marstaller, Lars; Burianová, Hana

    2013-06-01

    Co-speech gestures have been shown to interact with working memory (WM). However, no study has investigated whether there are individual differences in the effect of gestures on WM. Combining a novel gesture/no-gesture task and an operation span task, we examined the differences in WM accuracy between individuals who gestured and individuals who did not gesture in relation to their WM capacity. Our results showed individual differences in the gesture effect on WM. Specifically, only individuals with low WM capacity showed a reduced WM accuracy when they did not gesture. Individuals with low WM capacity who did gesture, as well as high-capacity individuals (irrespective of whether they gestured or not), did not show the effect. Our findings show that the interaction between co-speech gestures and WM is affected by an individual's WM load.

  17. Wake-field generation by the ponderomotive memory effect

    International Nuclear Information System (INIS)

    Wolf, U.; Schamel, H.

    1997-01-01

    An analytical and numerical investigation of the plasma response to an imposed high frequency wave packet with a slow explicit time-dependent envelope is presented. An underlying picture of ponderomotive effects is developed, which shows that the explicit time dependence forces us to treat the problem kinetically, and furthermore, that a wake field is generated by the ponderomotive memory effect. The latter supplements the well-known ponderomotive force and fake heating effect. Several perturbation schemes are compared showing that the influence of resonant particles, treated by the method of characteristics, has to be taken into account for Langmuir wave packets with kλ d ≥0.2, where k is the wave number and λ d the Debye length. A self-consistent Vlasov simulation shows the disappearance of the density depression in the case of immobile ions, whereas the wake-field pattern survives self-consistency. copyright 1997 The American Physical Society

  18. Memory effects in chaotic advection of inertial particles

    International Nuclear Information System (INIS)

    Daitche, Anton; Tél, Tamás

    2014-01-01

    A systematic investigation of the effect of the history force on particle advection is carried out for both heavy and light particles. General relations are given to identify parameter regions where the history force is expected to be comparable with the Stokes drag. As an illustrative example, a paradigmatic two-dimensional flow, the von Kármán flow is taken. For small (but not extremely small) particles all investigated dynamical properties turn out to heavily depend on the presence of memory when compared to the memoryless case: the history force generates a rather non-trivial dynamics that appears to weaken (but not to suppress) inertial effects, it enhances the overall contribution of viscosity. We explore the parameter space spanned by the particle size and the density ratio, and find a weaker tendency for accumulation in attractors and for caustics formation. The Lyapunov exponent of transients becomes larger with memory. Periodic attractors are found to have a very slow, t −1/2 type convergence towards the asymptotic form. We find that the concept of snapshot attractors is useful to understand this slow convergence: an ensemble of particles converges exponentially fast towards a snapshot attractor, which undergoes a slow shift for long times. (paper)

  19. Memory effect in M ≥ 7 earthquakes of Taiwan

    Science.gov (United States)

    Wang, Jeen-Hwa

    2014-07-01

    The M ≥ 7 earthquakes that occurred in the Taiwan region during 1906-2006 are taken to study the possibility of memory effect existing in the sequence of those large earthquakes. Those events are all mainshocks. The fluctuation analysis technique is applied to analyze two sequences in terms of earthquake magnitude and inter-event time represented in the natural time domain. For both magnitude and inter-event time, the calculations are made for three data sets, i.e., the original order data, the reverse-order data, and that of the mean values. Calculated results show that the exponents of scaling law of fluctuation versus window length are less than 0.5 for the sequences of both magnitude and inter-event time data. In addition, the phase portraits of two sequent magnitudes and two sequent inter-event times are also applied to explore if large (or small) earthquakes are followed by large (or small) events. Results lead to a negative answer. Together with all types of information in study, we make a conclusion that the earthquake sequence in study is short-term corrected and thus the short-term memory effect would be operative.

  20. Effects of Sun ginseng on memory enhancement and hippocampal neurogenesis.

    Science.gov (United States)

    Lee, Chang Hwan; Kim, Jong Min; Kim, Dong Hyun; Park, Se Jin; Liu, Xiaotong; Cai, Mudan; Hong, Jin Gyu; Park, Jeong Hill; Ryu, Jong Hoon

    2013-09-01

    Panax ginseng C.A. Meyer has been used in traditional herb prescriptions for thousands of years. A heat-processing method has been used to increase the efficacy of ginseng, yielding what is known as red ginseng. In addition, recently, a slightly modified heat-processing method was applied to ginseng, to obtain a new type of processed ginseng with increased biological activity; this new form of ginseng is referred to as Sun ginseng (SG). The aim of this study was to investigate the effect of SG on memory enhancement and neurogenesis in the hippocampal dentate gyrus (DG) region. The subchronic administration of SG (for 14 days) significantly increased the latency time in the passive avoidance task relative to the administration of the vehicle control (P memory-enhancing activities and that these effects are mediated, in part, by the increase in the levels of pERK and pAkt and by the increases in cell proliferation and cell survival. Copyright © 2012 John Wiley & Sons, Ltd.

  1. Memory effects in the relaxation of the Gaussian trap model

    Science.gov (United States)

    Diezemann, Gregor; Heuer, Andreas

    2011-03-01

    We investigate the memory effect in a simple model for glassy relaxation, a trap model with a Gaussian density of states. In this model, thermal equilibrium is reached at all finite temperatures and we therefore can consider jumps from low to high temperatures in addition to the quenches usually considered in aging studies. We show that the evolution of the energy following the Kovacs protocol can approximately be expressed as a difference of two monotonously decaying functions and thus show the existence of a so-called Kovacs hump whenever these functions are not single exponentials. It is well established that the Kovacs effect also occurs in the linear response regime, and we show that most of the gross features do not change dramatically when large temperature jumps are considered. However, there is one distinguishing feature that only exists beyond the linear regime, which we discuss in detail. For the memory experiment with inverted temperatures, i.e., jumping up and then down again, we find a very similar behavior apart from an opposite sign of the hump.

  2. Independent effects of colour on object identification and memory.

    Science.gov (United States)

    Lloyd-Jones, Toby J; Nakabayashi, Kazuyo

    2009-02-01

    We examined the effects of colour on object identification and memory using a study-test priming procedure with a coloured-object decision task at test (i.e., deciding whether an object is correctly coloured). Objects were selected to have a single associated colour and were either correctly or incorrectly coloured. In addition, object shape and colour were either spatially integrated (i.e., colour fell on the object surface) or spatially separated (i.e., colour formed the background to the object). Transforming the colour of an object from study to test (e.g., from a yellow banana to a purple banana) reduced priming of response times, as compared to when the object was untransformed. This utilization of colour information in object memory was not contingent upon colour falling on the object surface or whether the resulting configuration was of a correctly or incorrectly coloured object. In addition, we observed independent effects of colour on response times, whereby coloured-object decisions were more efficient for correctly than for incorrectly coloured objects but only when colour fell on the object surface. These findings provide evidence for two distinct mechanisms of shape-colour binding in object processing.

  3. Effects of the swimming exercise on the consolidation and persistence of auditory and contextual fear memory.

    Science.gov (United States)

    Faria, Rodolfo Souza; Gutierres, Luís Felipe Soares; Sobrinho, Fernando César Faria; Miranda, Iris do Vale; Reis, Júlia Dos; Dias, Elayne Vieira; Sartori, Cesar Renato; Moreira, Dalmo Antonio Ribeiro

    2016-08-15

    consolidation as well as persistence of conditioned fear memory. In addition, rats submitted to swimming exercise over six weeks showed an improved performance in the test of auditory-cued fear memory persistence, but not in the test of contextual fear memory persistence. Moreover, no significant effect from swimming exercise was observed on consolidation of both contextual and auditory fear memory. So, our study, revealing the effect of the swimming exercise on different stages of implicit memory of tone/foot shock conditioning, contributes to and complements the current knowledge about the environmental modulation of memory process. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. Modeling of strain effects on the device behaviors of ferroelectric memory field-effect transistors

    International Nuclear Information System (INIS)

    Yang, Feng; Hu, Guangda; Wu, Weibing; Yang, Changhong; Wu, Haitao; Tang, Minghua

    2013-01-01

    The influence of strains on the channel current–gate voltage behaviors and memory windows of ferroelectric memory field-effect transistors (FeMFETs) were studied using an improved model based on the Landau–Devonshire theory. ‘Channel potential–gate voltage’ ferroelectric polarization and silicon surface potential diagrams were constructed for strained single-domain BaTiO 3 FeMFETs. The compressive strains can increase (or decrease) the amplitude of transistor currents and enlarge memory windows. However, tensile strains only decrease the maximum value of transistor currents and compress memory windows. Mismatch strains were found to have a significant influence on the electrical behaviors of the devices, therefore, they must be considered in FeMFET device designing. (fast track communication)

  5. Decoherence effect on quantum-memory-assisted entropic uncertainty relations

    Science.gov (United States)

    Ming, Fei; Wang, Dong; Huang, Ai-Jun; Sun, Wen-Yang; Ye, Liu

    2018-01-01

    Uncertainty principle significantly provides a bound to predict precision of measurement with regard to any two incompatible observables, and thereby plays a nontrivial role in quantum precision measurement. In this work, we observe the dynamical features of the quantum-memory-assisted entropic uncertainty relations (EUR) for a pair of incompatible measurements in an open system characterized by local generalized amplitude damping (GAD) noises. Herein, we derive the dynamical evolution of the entropic uncertainty with respect to the measurement affecting by the canonical GAD noises when particle A is initially entangled with quantum memory B. Specifically, we examine the dynamics of EUR in the frame of three realistic scenarios: one case is that particle A is affected by environmental noise (GAD) while particle B as quantum memory is free from any noises, another case is that particle B is affected by the external noise while particle A is not, and the last case is that both of the particles suffer from the noises. By analytical methods, it turns out that the uncertainty is not full dependent of quantum correlation evolution of the composite system consisting of A and B, but the minimal conditional entropy of the measured subsystem. Furthermore, we present a possible physical interpretation for the behavior of the uncertainty evolution by means of the mixedness of the observed system; we argue that the uncertainty might be dramatically correlated with the systematic mixedness. Furthermore, we put forward a simple and effective strategy to reduce the measuring uncertainty of interest upon quantum partially collapsed measurement. Therefore, our explorations might offer an insight into the dynamics of the entropic uncertainty relation in a realistic system, and be of importance to quantum precision measurement during quantum information processing.

  6. Randomized controlled trial evaluating the temporal effects of high-intensity exercise on learning, short-term and long-term memory, and prospective memory.

    Science.gov (United States)

    Frith, Emily; Sng, Eveleen; Loprinzi, Paul D

    2017-11-01

    The broader purpose of this study was to examine the temporal effects of high-intensity exercise on learning, short-term and long-term retrospective memory and prospective memory. Among a sample of 88 young adult participants, 22 were randomized into one of four different groups: exercise before learning, control group, exercise during learning, and exercise after learning. The retrospective assessments (learning, short-term and long-term memory) were assessed using the Rey Auditory Verbal Learning Test. Long-term memory including a 20-min and 24-hr follow-up assessment. Prospective memory was assessed using a time-based procedure by having participants contact (via phone) the researchers at a follow-up time period. The exercise stimulus included a 15-min bout of progressive maximal exertion treadmill exercise. High-intensity exercise prior to memory encoding (vs. exercise during memory encoding or consolidation) was effective in enhancing long-term memory (for both 20-min and 24-h follow-up assessments). We did not observe a differential temporal effect of high-intensity exercise on short-term memory (immediate post-memory encoding), learning or prospective memory. The timing of high-intensity exercise may play an important role in facilitating long-term memory. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  7. Effects of Saccadic Bilateral Eye Movements on Episodic & Semantic Autobiographical Memory Fluency

    Directory of Open Access Journals (Sweden)

    Andrew eParker

    2013-09-01

    Full Text Available Performing a sequence of fast saccadic horizontal eye movements has been shown to facilitate performance on a range of cognitive tasks, including the retrieval of episodic memories. One explanation for these effects is based on the hypothesis that saccadic eye movements increase hemispheric interaction, and that such interactions are important for particular types of memory. The aim of the current research was to assess the effect of horizontal saccadic eye movements on the retrieval of both episodic autobiographical memory (event/incident based memory and semantic autobiographical memory (fact based memory over recent and more distant time periods. It was found that saccadic eye movements facilitated the retrieval of episodic autobiographical memories (over all time periods but not semantic autobiographical memories. In addition, eye movements did not enhance the retrieval of non-autobiographical semantic memory. This finding illustrates a dissociation between the episodic and semantic characteristics of personal memory and is considered within the context of hemispheric contributions to episodic memory performance.

  8. Martensitic transformations and the shape memory effect in Ti-Zr-Nb-Al high-temperature shape memory alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fei; Yu, Zhiguo; Xiong, Chengyang [School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Key Laboratory of Aerospace Materials and Performance (Ministry of Education), Beihang University, Beijing 100191 (China); Qu, Wentao; Yuan, Bifei [School of Mechanical Engineering, Xi’an Shiyou University, Xi’an 710065 (China); Wang, Zhenguo [School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Key Laboratory of Aerospace Materials and Performance (Ministry of Education), Beihang University, Beijing 100191 (China); Li, Yan, E-mail: liyan@buaa.edu.cn [School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Key Laboratory of Aerospace Materials and Performance (Ministry of Education), Beihang University, Beijing 100191 (China)

    2017-01-02

    The microstructures, phase transformations, mechanical properties and shape memory effect of Ti-20Zr-10Nb-xAl (x=1, 2, 3, 4 at%) alloys were investigated. The X-ray diffraction results show that the alloys are composed of a single martensitic α″-phase and that the corresponding unit cell volume decreases with increasing Al content. The reverse martensitic transformation start temperature (A{sub s}) of the Ti-20Zr-10Nb-Al alloy is 534 K and decreases with increasing Al content. The addition of Al results in solid solution strengthening and grain refinement strengthening, thus improving the mechanical properties and the shape memory effect of the Ti-20Zr-10 Nb-xAl alloys. The Ti-20Zr-10Nb-3Al alloy shows the greatest shape memory strain (3.2%) and the largest tensile strain (17.6%) as well as a very high tensile strength (886 MPa).

  9. Electrophysiological Repetition Effects in Persons with Mild Cognitive Impairment depend upon Working Memory Demand.

    Science.gov (United States)

    Broster, Lucas S; Jenkins, Shonna L; Holmes, Sarah D; Edwards, Matthew G; Jicha, Gregory A; Jiang, Yang

    2018-05-07

    Forms of implicit memory, including repetition effects, are preserved relative to explicit memory in clinical Alzheimer's disease. Consequently, cognitive interventions for persons with Alzheimer's disease have been developed that leverage this fact. However, despite the clinical robustness of behavioral repetition effects, altered neural mechanisms of repetition effects are studied as biomarkers of both clinical Alzheimer's disease and pre-morbid Alzheimer's changes in the brain. We hypothesized that the clinical preservation of behavioral repetition effects results in part from concurrent operation of discrete memory systems. We developed two experiments that included probes of emotional repetition effects differing in that one included an embedded working memory task. We found that neural repetition effects manifested in patients with amnestic mild cognitive impairment, the earliest form of clinical Alzheimer's disease, during emotional working memory tasks, but they did not manifest during the task that lacked the embedded working memory manipulation. Specifically, the working memory task evoked neural repetition effects in the P600 time-window, but the same neural mechanism was only minimally implicated in the task without a working memory component. We also found that group differences in behavioral repetition effects were smaller in the experiment with a working memory task. We suggest that cross-domain cognitive challenge can expose "defunct" neural capabilities of individuals with amnestic mild cognitive impairment. Copyright © 2018. Published by Elsevier Ltd.

  10. Effects of zolpidem on sedation, anxiety, and memory in the plus-maze discriminative avoidance task.

    Science.gov (United States)

    Zanin, Karina A; Patti, Camilla L; Sanday, Leandro; Fernandes-Santos, Luciano; Oliveira, Larissa C; Poyares, Dalva; Tufik, Sergio; Frussa-Filho, Roberto

    2013-04-01

    Zolpidem (Zolp), a hypnotic drug prescribed to treat insomnia, may have negative effects on memory, but reports are inconsistent. We examined the effects of acute doses of Zolp (2, 5, or 10 mg/kg, i.p.) on memory formation (learning, consolidation, and retrieval) using the plus-maze discriminative avoidance task. Mice were acutely treated with Zolp 30 min before training or testing. In addition, the effects of Zolp and midazolam (Mid; a classic benzodiazepine) on consolidation at different time points were examined. The possible role of state dependency was investigated using combined pre-training and pre-test treatments. Zolp produced a dose-dependent sedative effect, without modifying anxiety-like behavior. The pre-training administration of 5 or 10 mg/kg resulted in retention deficits. When administered immediately after training or before testing, memory was preserved. Zolp post-training administration (2 or 3 h) impaired subsequent memory. There was no participation of state dependency phenomenon in the amnestic effects of Zolp. Similar to Zolp, Mid impaired memory consolidation when administered 1 h after training. Amnestic effects occurred when Zolp was administered either before or 2-3 h after training. These memory deficits are not related to state dependency. Moreover, Zolp did not impair memory retrieval. Notably, the memory-impairing effects of Zolp are similar to those of Mid, with the exception of the time point at which the drug can modify consolidation. Finally, the memory effects were unrelated to sedation or anxiolysis.

  11. Glucoregulatory and order effects on verbal episodic memory in healthy adolescents after oral glucose administration.

    Science.gov (United States)

    Smith, Michael A; Foster, Jonathan K

    2008-10-01

    The ingestion of oral glucose has been observed to facilitate memory performance in both elderly individuals and in young adults. However, fewer studies have investigated the effect of glucose on memory in children or adolescents. In the present study, the ingestion of a glucose laden drink was observed to enhance verbal episodic memory performance in healthy adolescents under conditions of divided attention, relative to a placebo drink. Further analyses found that this glucose memory facilitation effect was observed only in adolescents exhibiting better glucoregulatory efficiency. These findings demonstrate that the glucose memory facilitation effect can be generalised to younger individuals. The importance of controlling for treatment order in within-subjects designs investigating the glucose memory enhancement effect is also discussed.

  12. Effect of adding Si on shape memory effect in Co-Ni alloy system

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Weimin [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China); Liu Yan [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Jiang Bohong [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China)]. E-mail: bhjiang@sjtu.edu.cn; Zhou Pingnan [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China)

    2006-11-25

    In this paper, the effect of adding Si to Co-31.5 mass% Ni alloys on fcc-hcp martensitic transformation is investigated. The Co-Ni-Si ternary alloys with different amount of Si from 1 to 5 mass% were prepared. The stacking fault probability of Co-Ni-Si polycrystalline alloys were determined by X-ray diffraction profile analysis and compared with the binary Co-Ni alloy. The results show that the stacking fault probability of the fcc phase of alloys increases with increasing Si content. The effect of Si on phase transformation and shape memory behavior is evaluated. The experimental results show that both the critical strength and the shape memory effect of the ternary alloys will increase by the addition of Si. The improvement mechanism of the shape memory effect by adding Si to binary Co-Ni alloys is discussed.

  13. A Memristor as Multi-Bit Memory: Feasibility Analysis

    Directory of Open Access Journals (Sweden)

    O. Bass

    2015-06-01

    Full Text Available The use of emerging memristor materials for advanced electrical devices such as multi-valued logic is expected to outperform today's binary logic digital technologies. We show here an example for such non-binary device with the design of a multi-bit memory. While conventional memory cells can store only 1 bit, memristors-based multi-bit cells can store more information within single device thus increasing the information storage density. Such devices can potentially utilize the non-linear resistance of memristor materials for efficient information storage. We analyze the performance of such memory devices based on their expected variations in order to determine the viability of memristor-based multi-bit memory. A design of read/write scheme and a simple model for this cell, lay grounds for full integration of memristor multi-bit memory cell.

  14. The Effects of Goal Relevance and Perceptual Features on Emotional Items and Associative Memory

    Directory of Open Access Journals (Sweden)

    Wei B. Mao

    2017-07-01

    Full Text Available Showing an emotional item in a neutral background scene often leads to enhanced memory for the emotional item and impaired associative memory for background details. Meanwhile, both top–down goal relevance and bottom–up perceptual features played important roles in memory binding. We conducted two experiments and aimed to further examine the effects of goal relevance and perceptual features on emotional items and associative memory. By manipulating goal relevance (asking participants to categorize only each item image as living or non-living or to categorize each whole composite picture consisted of item image and background scene as natural scene or manufactured scene and perceptual features (controlling visual contrast and visual familiarity in two experiments, we found that both high goal relevance and salient perceptual features (high salience of items vs. high familiarity of items could promote emotional item memory, but they had different effects on associative memory for emotional items and neutral backgrounds. Specifically, high goal relevance and high perceptual-salience of items could jointly impair the associative memory for emotional items and neutral backgrounds, while the effect of item familiarity on associative memory for emotional items would be modulated by goal relevance. High familiarity of items could increase associative memory for negative items and neutral backgrounds only in the low goal relevance condition. These findings suggest the effect of emotion on associative memory is not only related to attentional capture elicited by emotion, but also can be affected by goal relevance and perceptual features of stimulus.

  15. The Effects of Goal Relevance and Perceptual Features on Emotional Items and Associative Memory.

    Science.gov (United States)

    Mao, Wei B; An, Shu; Yang, Xiao F

    2017-01-01

    Showing an emotional item in a neutral background scene often leads to enhanced memory for the emotional item and impaired associative memory for background details. Meanwhile, both top-down goal relevance and bottom-up perceptual features played important roles in memory binding. We conducted two experiments and aimed to further examine the effects of goal relevance and perceptual features on emotional items and associative memory. By manipulating goal relevance (asking participants to categorize only each item image as living or non-living or to categorize each whole composite picture consisted of item image and background scene as natural scene or manufactured scene) and perceptual features (controlling visual contrast and visual familiarity) in two experiments, we found that both high goal relevance and salient perceptual features (high salience of items vs. high familiarity of items) could promote emotional item memory, but they had different effects on associative memory for emotional items and neutral backgrounds. Specifically, high goal relevance and high perceptual-salience of items could jointly impair the associative memory for emotional items and neutral backgrounds, while the effect of item familiarity on associative memory for emotional items would be modulated by goal relevance. High familiarity of items could increase associative memory for negative items and neutral backgrounds only in the low goal relevance condition. These findings suggest the effect of emotion on associative memory is not only related to attentional capture elicited by emotion, but also can be affected by goal relevance and perceptual features of stimulus.

  16. Effects of Task Instruction on Autobiographical Memory Specificity in Young and Older Adults

    Science.gov (United States)

    Ford, Jaclyn Hennessey; Rubin, David C.; Giovanello, Kelly S.

    2013-01-01

    Older adults tend to retrieve autobiographical information that is overly general (i.e. not restricted to a single event, termed the overgenerality effect) relative to young adults’ specific memories. A vast majority of studies that have reported overgenerality effects explicitly instruct participants to retrieve specific memories, thereby requiring participants to maintain task goals, inhibit inappropriate responses, and control their memory search. Since these processes are impaired in healthy aging, it is important to determine whether such task instructions influence the magnitude of the overgenerality effect in older adults. In the current study, participants retrieved autobiographical memories during presentation of musical clips. Task instructions were manipulated to separate age-related differences in the specificity of underlying memory representations from age-related differences in following task instructions. Whereas young adults modulated memory specificity based on task demands, older adults did not. These findings suggest that reported rates of overgenerality in older adults’ memories may include age-related differences in memory representation, as well as differences in task compliance. Such findings provide a better understanding of the underlying cognitive mechanisms involved in age-related changes in autobiographical memory and may also be valuable for future research examining effects of overgeneral memory on general well-being. PMID:23915176

  17. Effects of task instruction on autobiographical memory specificity in young and older adults.

    Science.gov (United States)

    Ford, Jaclyn Hennessey; Rubin, David C; Giovanello, Kelly S

    2014-01-01

    Older adults tend to retrieve autobiographical information that is overly general (i.e., not restricted to a single event, termed the overgenerality effect) relative to young adults' specific memories. A vast majority of studies that have reported overgenerality effects explicitly instruct participants to retrieve specific memories, thereby requiring participants to maintain task goals, inhibit inappropriate responses, and control their memory search. Since these processes are impaired in healthy ageing, it is important to determine whether such task instructions influence the magnitude of the overgenerality effect in older adults. In the current study participants retrieved autobiographical memories during presentation of musical clips. Task instructions were manipulated to separate age-related differences in the specificity of underlying memory representations from age-related differences in following task instructions. Whereas young adults modulated memory specificity based on task demands, older adults did not. These findings suggest that reported rates of overgenerality in older adults' memories might include age-related differences in memory representation, as well as differences in task compliance. Such findings provide a better understanding of the underlying cognitive mechanisms involved in age-related changes in autobiographical memory and may also be valuable for future research examining effects of overgeneral memory on general well-being.

  18. The descriptive set-theoretic complexity of the set of points of continuity of a multi-valued function (Extended Abstract

    Directory of Open Access Journals (Sweden)

    Vassilios Gregoriades

    2010-06-01

    Full Text Available In this article we treat a notion of continuity for a multi-valued function F and we compute the descriptive set-theoretic complexity of the set of all x for which F is continuous at x. We give conditions under which the latter set is either a G_delta set or the countable union of G_delta sets. Also we provide a counterexample which shows that the latter result is optimum under the same conditions. Moreover we prove that those conditions are necessary in order to obtain that the set of points of continuity of F is Borel i.e., we show that if we drop some of the previous conditions then there is a multi-valued function F whose graph is a Borel set and the set of points of continuity of F is not a Borel set. Finally we give some analogue results regarding a stronger notion of continuity for a multi-valued function. This article is motivated by a question of M. Ziegler in "Real Computation with Least Discrete Advice: A Complexity Theory of Nonuniform Computability with Applications to Linear Algebra", (submitted.

  19. The Effects of Spatial Contextual Familiarity on Remembered Scenes, Episodic Memories, and Imagined Future Events

    Science.gov (United States)

    Robin, Jessica; Moscovitch, Morris

    2014-01-01

    Several recent studies have explored the effect of contextual familiarity on remembered and imagined events. The aim of this study was to examine the extent of this effect by comparing the effect of cuing spatial memories, episodic memories, and imagined future events with spatial contextual cues of varying levels of familiarity. We used…

  20. Individual Differences in the Effects of Retrieval from Long-Term Memory

    Science.gov (United States)

    Brewer, Gene A.; Unsworth, Nash

    2012-01-01

    The current study examined individual differences in the effects of retrieval from long-term memory (i.e., the testing effect). The effects of retrieving from memory make tested information more accessible for future retrieval attempts. Despite the broad applied ramifications of such a potent memorization technique there is a paucity of research…

  1. Deja Vu All Over Again: Effects of Reenactment on Toddlers' Event Memory.

    Science.gov (United States)

    Sheffield, Ellyn G.; Hudson, Judith A.

    1998-01-01

    Four experiments examined the effects of reenactment on 18-month-olds' event memory. Results indicated that reenacting novel activities in a laboratory playroom improved event memory. Reenactment was more effective after a time delay, and the effects of timing of reenactment were more pronounced after a six-month delay. Reenacting half of the…

  2. Counteracting effect of threat on reward enhancements during working memory.

    Science.gov (United States)

    Choi, Jong Moon; Padmala, Srikanth; Pessoa, Luiz

    2015-01-01

    Cognitive performance has been shown to be enhanced when performance-based rewards are at stake. On the other hand, task-irrelevant threat processing has been shown to have detrimental effects during several cognitive tasks. Crucially, the impact of reward and threat on cognition has been studied largely independently of one another. Hence, our understanding of how reward and threat simultaneously contribute to performance is incomplete. To fill in this gap, the present study investigated how reward and threat interact with one another during a cognitive task. We found that threat of shock counteracted the beneficial effect of reward during a working memory task. Furthermore, individual differences in self-reported reward-sensitivity and anxiety were linked to the extent to which reward and threat interacted during behaviour. Together, the current findings contribute to a limited but growing literature unravelling how positive and negative information processing jointly influence cognition.

  3. Effect of cognitive load on working memory forgetting in aging.

    Science.gov (United States)

    Baumans, Christine; Adam, Stephane; Seron, Xavier

    2012-01-01

    Functional approaches to working memory (WM) have been proposed recently to better investigate "maintenance" and "processing" mechanisms. The cognitive load (CL) hypothesis presented in the "Time-Based Resource-Sharing" model (Barrouillet & Camos, 2007) suggests that forgetting from WM (maintenance) can be investigated by varying the presentation rate and processing speed (processing). In this study, young and elderly participants were compared on WM tasks in which the difference in processing speed was controlled by CL manipulations. Two main results were found. First, when time constraints (CL) were matched for the two groups, no aging effect was observed. Second, whereas a large variation in CL affected WM performance, a small CL manipulation had no effect on the elderly. This suggests that WM forgetting cannot be completely accounted for by the CL hypothesis. Rather, it highlights the need to explore restoration times in particular, and the nature of the refreshment mechanisms within maintenance.

  4. The effects of attention on perceptual implicit memory.

    Science.gov (United States)

    Rajaram, S; Srinivas, K; Travers, S

    2001-10-01

    Reports on the effects of dividing attention at study on subsequent perceptual priming suggest that perceptual priming is generally unaffected by attentional manipulations as long as word identity is processed. We tested this hypothesis in three experiments by using the implicit word fragment completion and word stem completion tasks. Division of attention was instantiated with the Stroop task in order to ensure the processing of word identity even when the participant's attention was directed to a stimulus attribute other than the word itself. Under these conditions, we found that even though perceptual priming was significant, it was significantly reduced in magnitude. A stem cued recall test in Experiment 2 confirmed a more deleterious effect of divided attention on explicit memory. Taken together, our findings delineate the relative contributions of perceptual analysis and attentional processes in mediating perceptual priming on two ubiquitously used tasks of word fragment completion and word stem completion.

  5. The Effect of Overgeneral Autobiographical Memory Retrieval on Rumination

    Directory of Open Access Journals (Sweden)

    Filip Raes

    2006-03-01

    Full Text Available From distinct research traditions rumination and overgeneral autobiographical memory retrieval (OGM have emerged as two vulnerability markers for depression and depressive relapse (Nolen-Hoeksema, 2004; Williams, 2004. Recent research further suggests a causal relation between rumination and OGM (e.g., Watkins & Teasdale, 2001. The present study investigated the inverse relationship, that is, OGM causally influencing ruminative thinking. A scrambled sentences procedure was used to assess the extent to which 112 student participants were engaged in a mental mode consistent with ruminative thinking following either a specific or overgeneral memory retrieval style manipulation. Trait rumination was also assessed prior to the experimental retrieval manipulation, using a self-report scale. It was found that high ruminators, following an overgeneral (as compared to a specific retrieval style, unscrambled sentences relatively more into sentences with a ruminative meaning. In non or low ruminators this retrieval style manipulation had no such effect. Alongside the findings of Watkins and colleagues (e.g., Watkins & Teasdale, 2001, the present results are consistent with the view of rumination and OGM as two mutually reinforcing vulnerability factors for depression (Williams, 1996, 2004.

  6. The effects of general anaesthesia on memory in children: a comparison between propofol and sevoflurane.

    Science.gov (United States)

    Yin, J; Wang, S-L; Liu, X-B

    2014-02-01

    We studied the effects of general anaesthesia on memory 7 days and 3 months following elective hernia surgery. Sixty children aged between 7 and 13 years were randomly allocated to receive either propofol or sevoflurane. Memory was classified into immediate, short-term and long-term memory and assessed using the Wechsler Memory Scale-Propofol impaired short-term memory 7 days postoperatively compared with pre-operative values (image recalling: p = 0.02, figure recognition: p = 0.01, visual reproduction: p = 0.03) but recovered to baseline levels 3 months following surgery. Neither general anaesthetic affected immediate or long-term memory. We conclude that propofol impairs short-term memory postoperatively in children. © 2013 The Association of Anaesthetists of Great Britain and Ireland.

  7. The effects of glucose dose and dual-task performance on memory for emotional material

    OpenAIRE

    Brandt, Karen; Sünram-Lea, Sandra; Jenkinson, Paul; Jones, Emma

    2010-01-01

    Whilst previous research has shown that glucose administration can boost memory performance, research investigating the effects of glucose on memory for emotional material has produced mixed findings. Whereas some research has shown that glucose impairs memory for emotional material, other research has shown that glucose has no effect on emotional items. The aim of the present research was therefore to provide further investigation of the role of glucose on the recognition of words with emoti...

  8. Focusing on Attention: The Effects of Working Memory Capacity and Load on Selective Attention.

    OpenAIRE

    Ahmed, Lubna; de Fockert, Jan

    2012-01-01

    Background\\ud \\ud Working memory (WM) is imperative for effective selective attention. Distractibility is greater under conditions of high (vs. low) concurrent working memory load (WML), and in individuals with low (vs. high) working memory capacity (WMC). In the current experiments, we recorded the flanker task performance of individuals with high and low WMC during low and high WML, to investigate the combined effect of WML and WMC on selective attention.\\ud \\ud Methodology/Principal Findin...

  9. Effects of low doses of alcohol on declarative memory in humans

    Directory of Open Access Journals (Sweden)

    José Arturo Bríñez-Horta

    2011-09-01

    Full Text Available This study assessed the effect of low doses of alcohol on two elements of explicit or declarative memory, in 16 participants, 8 women and 8 men, with The Weschler Memory Scale III Text Test. A factorial 2 * 4 counterbalanced with repeated measures design was used. There were no statistically significant differences by gender, but there were differences among doses, specially 0.150 g / Kg., which reduced episodic and semantic retrieval, between 43.9 and 62.9 % of effect strength, in intermediate term memory. These results provided evidence that alcohol in low doses has a more pronounced effect in semantic, rather than episodic memory, in the middle term

  10. Contextual effects in visual working memory reveal hierarchically structured memory representations.

    Science.gov (United States)

    Brady, Timothy F; Alvarez, George A

    2015-01-01

    Influential slot and resource models of visual working memory make the assumption that items are stored in memory as independent units, and that there are no interactions between them. Consequently, these models predict that the number of items to be remembered (the set size) is the primary determinant of working memory performance, and therefore these models quantify memory capacity in terms of the number and quality of individual items that can be stored. Here we demonstrate that there is substantial variance in display difficulty within a single set size, suggesting that limits based on the number of individual items alone cannot explain working memory storage. We asked hundreds of participants to remember the same sets of displays, and discovered that participants were highly consistent in terms of which items and displays were hardest or easiest to remember. Although a simple grouping or chunking strategy could not explain this individual-display variability, a model with multiple, interacting levels of representation could explain some of the display-by-display differences. Specifically, a model that includes a hierarchical representation of items plus the mean and variance of sets of the colors on the display successfully accounts for some of the variability across displays. We conclude that working memory representations are composed only in part of individual, independent object representations, and that a major factor in how many items are remembered on a particular display is interitem representations such as perceptual grouping, ensemble, and texture representations.

  11. Effects of memory strategy training on performance and event-related brain potentials of children with ADHD in an episodic memory task.

    Science.gov (United States)

    Jonkman, Lisa M; Hurks, Petra P; Schleepen, Tamara M J

    2016-10-01

    Evidence for memory problems in children with attention deficit hyperactivity disorder (ADHD) is accumulating. Attempting to counter such problems, in the present study children with ADHD aged 8-12 years underwent a six-week metacognitive memory strategy training (MST) or one of two other active trainings, either a metacognitive attention-perceptual-motor training (APM) or placebo training consisting of playing board games (PLA). Effects of the training on episodic memory and underlying brain processes were investigated by comparing performance and event-related brain potentials (ERPs) on pre- and post-training sessions in an old/new recognition task between the three training groups. Potential far transfer effects of the memory strategy training were investigated by measuring performance on neuropsychological attention and memory-span tasks and parent-rated ADHD symptoms. The metacognitive memory strategy training led to significantly improved memory performance and enhanced amplitude of left parietal P600 activity associated with the process of memory recollection when compared to PLA, but APM training evoked similar improvements. Memory performance gains were significantly correlated with the memory-related ERP effects. Preliminary far transfer effects of MST training were found on attention and working memory performance and on parent-rated ADHD symptoms, although these results need replication with larger and better IQ-matched groups.

  12. Analysis of cell adhesion during early stages of colon cancer based on an extended multi-valued logic approach.

    Science.gov (United States)

    Guebel, Daniel V; Schmitz, Ulf; Wolkenhauer, Olaf; Vera, Julio

    2012-04-01

    Cell adhesion in the normal colon is typically associated with differentiated cells, whereas in cancerous colon it is associated with advanced tumors. For advanced tumors growing evidence supports the existence of stem-like cells that have originated from transdifferentiation. Because stem cells can also be transformed in their own niche, at the base of the Lieberkühn's crypts, we conjectured that cell adhesion can also be critical in early tumorigenesis. To assess this hypothesis we built an annotated, multi-valued logic model addressing cell adhesion of normal and tumorigenic stem cells in the human colon. The model accounts for (i) events involving intercellular adhesion structures, (ii) interactions involving cytoskeleton-related structures, (iii) compartmental distribution of α/β/γ/δ-catenins, and (iv) variations in critical cell adhesion regulators (e.g., ILK, FAK, IQGAP, SNAIL, Caveolin). We developed a method that can deal with graded multiple inhibitions, something which is not possible with conventional logical approaches. The model comprises 315 species (including 26 genes), interconnected by 269 reactions. Simulations of the model covered six scenarios, which considered two types of colonic cells (stem vs. differentiated cells), under three conditions (normal, stressed and tumor). Each condition results from the combination of 92 inputs. We compared our multi-valued logic approach with the conventional Boolean approach for one specific example and validated the predictions against published data. Our analysis suggests that stem cells in their niche synthesize high levels of cytoplasmatic E-cadherin and CdhEP(Ser684,686,692), even under normal-mitogenic stimulus or tumorigenic conditions. Under these conditions, E-cadherin would be incorporated into the plasmatic membrane, but only as a non-adhesive CdhE_β-catenin_IQGAP complex. Under stress conditions, however, this complex could be displaced, yielding adhesive Cdh

  13. Models for Total-Dose Radiation Effects in Non-Volatile Memory

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Philip Montgomery; Wix, Steven D.

    2017-04-01

    The objective of this work is to develop models to predict radiation effects in non- volatile memory: flash memory and ferroelectric RAM. In flash memory experiments have found that the internal high-voltage generators (charge pumps) are the most sensitive to radiation damage. Models are presented for radiation effects in charge pumps that demonstrate the experimental results. Floating gate models are developed for the memory cell in two types of flash memory devices by Intel and Samsung. These models utilize Fowler-Nordheim tunneling and hot electron injection to charge and erase the floating gate. Erase times are calculated from the models and compared with experimental results for different radiation doses. FRAM is less sensitive to radiation than flash memory, but measurements show that above 100 Krad FRAM suffers from a large increase in leakage current. A model for this effect is developed which compares closely with the measurements.

  14. Effective thermo-mechanical properties and shape memory effect of CNT/SMP composites

    Science.gov (United States)

    Yang, Qingsheng; Liu, Xia; Leng, Fangfang

    2009-07-01

    Shape memory polymer (SMP) has been applied in many fields as intelligent sensors and actuators. In order to improve the mechanical properties and recovery force of SMP, the addition of minor amounts of carbon nanotubes (CNT) into SMP has attracted wide attention. A micromechanical model and thermo-mechanical properties of CNT/SMP composites were studied in this paper. The thermo-mechanical constitutive relation of intellectual composites with isotropic and transversely isotropic CNT was obtained. Moreover, the shape memory effect of CNT/SMP composites and the effect of temperature and the volume fraction of CNT were discussed. The work shows that CNT/SMP composites exhibit excellent macroscopic thermo-mechanical properties and shape memory effect, while both of them can be affected remarkably by temperature and the microstructure parameters.

  15. Exogenous and endogenous spatial attention effects on visuospatial working memory.

    Science.gov (United States)

    Botta, Fabiano; Santangelo, Valerio; Raffone, Antonino; Lupiáñez, Juan; Belardinelli, Marta Olivetti

    2010-08-01

    In this study, we investigate how exogenous and endogenous orienting of spatial attention affect visuospatial working memory (VSWM). Specifically, we focused on two attentional effects and their consequences on storage in VSWM, when exogenous (Experiment 1) or endogenous (Experiment 2) orienting cues were used. The first effect, known as the meridian effect, is given by a decrement in behavioural performance when spatial cues and targets are presented in locations separated by vertical and/or horizontal meridians. The second effect, known as the distance effect, is given by a decrement in the orienting effects as a function of the spatial distance between cues and targets. Our results revealed a dissociation between exogenous and endogenous orienting mechanisms in terms of both meridian and distance effects. We found that meridian crossing affects performance only when endogenous cues were used. Specifically, VSWM performance with endogenous cueing depended more on the number of meridian crossings than on distance between cue and target. By contrast, a U-shaped distance dependency was observed using exogenous cues. Our findings therefore suggest that exogenous and endogenous orienting mechanisms lead to different forms of attentional bias for storage in VSWM.

  16. Prospective memory failures in aviation: effects of cue salience, workload, and individual differences.

    Science.gov (United States)

    Van Benthem, Kathleen D; Herdman, Chris M; Tolton, Rani G; LeFevre, Jo-Anne

    2015-04-01

    Prospective memory allows people to complete intended tasks in the future. Prospective memory failures, such as pilots forgetting to inform pattern traffic of their locations, can have fatal consequences. The present research examined the impact of system factors (memory cue salience and workload) and individual differences (pilot age, cognitive health, and expertise) on prospective memory for communication tasks in the cockpit. Pilots (N = 101) flew a Cessna 172 simulator at a non-towered aerodrome while maintaining communication with traffic and attending to flight parameters. Memory cue salience (the prominence of cues that signal an intended action) and workload were manipulated. Prospective memory was measured as radio call completion rates. Pilots' prospective memory was adversely affected by low-salience cues and high workload. An interaction of cue salience, pilots' age, and cognitive health reflected the effects of system and individual difference factors on prospective memory failures. For example, younger pilots with low levels of cognitive health completed 78% of the radio calls associated with low-salience memory cues, whereas older pilots with low cognitive health scores completed just 61% of similar radio calls. Our findings suggest that technologies designed to signal intended future tasks should target those tasks with inherently low-salience memory cues. In addition, increasing the salience of memory cues is most likely to benefit pilots with lower levels of cognitive health in high-workload conditions.

  17. The effect of background music on episodic memory and autonomic responses: listening to emotionally touching music enhances facial memory capacity

    Science.gov (United States)

    Mado Proverbio, C.A. Alice; Lozano Nasi, Valentina; Alessandra Arcari, Laura; De Benedetto, Francesco; Guardamagna, Matteo; Gazzola, Martina; Zani, Alberto

    2015-01-01

    The aim of this study was to investigate how background auditory processing can affect other perceptual and cognitive processes as a function of stimulus content, style and emotional nature. Previous studies have offered contrasting evidence, and it has been recently shown that listening to music negatively affected concurrent mental processing in the elderly but not in young adults. To further investigate this matter, the effect of listening to music vs. listening to the sound of rain or silence was examined by administering an old/new face memory task (involving 448 unknown faces) to a group of 54 non-musician university students. Heart rate and diastolic and systolic blood pressure were measured during an explicit face study session that was followed by a memory test. The results indicated that more efficient and faster recall of faces occurred under conditions of silence or when participants were listening to emotionally touching music. Whereas auditory background (e.g., rain or joyful music) interfered with memory encoding, listening to emotionally touching music improved memory and significantly increased heart rate. It is hypothesized that touching music is able to modify the visual perception of faces by binding facial properties with auditory and emotionally charged information (music), which may therefore result in deeper memory encoding. PMID:26469712

  18. The effect of background music on episodic memory and autonomic responses: listening to emotionally touching music enhances facial memory capacity.

    Science.gov (United States)

    Proverbio, Alice Mado; Mado Proverbio, C A Alice; Lozano Nasi, Valentina; Alessandra Arcari, Laura; De Benedetto, Francesco; Guardamagna, Matteo; Gazzola, Martina; Zani, Alberto

    2015-10-15

    The aim of this study was to investigate how background auditory processing can affect other perceptual and cognitive processes as a function of stimulus content, style and emotional nature. Previous studies have offered contrasting evidence, and it has been recently shown that listening to music negatively affected concurrent mental processing in the elderly but not in young adults. To further investigate this matter, the effect of listening to music vs. listening to the sound of rain or silence was examined by administering an old/new face memory task (involving 448 unknown faces) to a group of 54 non-musician university students. Heart rate and diastolic and systolic blood pressure were measured during an explicit face study session that was followed by a memory test. The results indicated that more efficient and faster recall of faces occurred under conditions of silence or when participants were listening to emotionally touching music. Whereas auditory background (e.g., rain or joyful music) interfered with memory encoding, listening to emotionally touching music improved memory and significantly increased heart rate. It is hypothesized that touching music is able to modify the visual perception of faces by binding facial properties with auditory and emotionally charged information (music), which may therefore result in deeper memory encoding.

  19. Enhancing effects of chronic lithium on memory in the rat.

    Science.gov (United States)

    Tsaltas, Eleftheria; Kontis, Dimitrios; Boulougouris, Vasileios; Papakosta, Vasiliki-Maria; Giannou, Haralambos; Poulopoulou, Cornelia; Soldatos, Constantine

    2007-02-12

    In spite of recent enrichment of neurochemical and behavioural data establishing a neuroprotective role for lithium, its primary effects on cognitive functioning remain ambiguous. This study examines chronic lithium effects on spatial working memory and long-term retention. In three discrete experiments, rats subjected to 30 daily intraperitoneal injections (2mmol/kg) of lithium (lithium groups: serum lithium=0.5+/-0.4mEq/l, 12h post-injection) or saline (controls) were trained in 0-s delay T-maze alternation and then tested in 30-, 45- and 60-s delay alternation (Experiments 1, 2, 3, respectively). Animals from Experiment 1 were further tested in one-trial step-through passive avoidance under mild shock parameters (0.5mA, 1s). Retention was assessed 6h later. Daily lithium or saline injections continued throughout behavioural testing. Lithium animals were indistinguishable from controls during 0-delay alternation baseline (Experiments 1-3, accuracy>88%) but showed significantly higher accuracy than controls at 30- and 45-s delays (93% versus 85% and 92% versus 82%, Experiments 1 and 2, respectively). At 60-s delay (Experiment 3) this beneficial effect of lithium was no longer apparent (lithium and control accuracy=78%). In Experiment 4, the shock used did not support 6-h passive avoidance retention in controls, whereas lithium animals showed significant step-through latency increases. Chronic lithium enhanced spatial working memory and promoted long-term retention of a weak aversive contingency. The results suggest that lithium may have potential as a cognitive enhancer.

  20. The effects of caffeine and expectancy on attention and memory.

    Science.gov (United States)

    Oei, Adam; Hartley, Laurence R

    2005-04-01

    The present study contrasted caffeine's effects on individuals who expect caffeine to stimulate them and those who do not. Secondly, whether a message that caffeine rather than placebo was administered would also affect these two groups of subjects differently was investigated. The study was conducted single-blind in a 2x2x2 mixed design. The between subjects factor was whether they expected caffeine to stimulate them (E+) or not (E-) according to their self reports obtained before the experiment began. The within subjects factors were message (told caffeine vs told placebo) and beverage type (given caffeine vs placebo). Sixteen subjects in each group (n=32) performed on signal detection, memory scanning and delayed free recall tasks following ingestion of either caffeinated or decaffeinated coffee on two sessions each, a total of four experimental sessions. On each session, subjects were given a message regarding their drink (told caffeine vs told placebo). However, on two sessions there was a mismatch between the message and drink given. For signal detection, performance under caffeine was better than placebo in the E+ but not the E- group. However, subjects in the E+ group did not benefit more than the E- group in either message condition. On memory scanning, detections and false alarms did not differ for either beverage, nor was there a differential finding in the E+ and E- groups. However, reaction time under caffeine condition was shorter. No effects of message were found. Caffeine and message also did not have any effect on performance on the delayed free recall task. The hypothesis that caffeine and message would affect E+ and E- subjects differentially was partly supported. Copyright (c) 2005 John Wiley & Sons, Ltd.

  1. The Effects of β-Adrenergic Blockade on the Degrading Effects of Eye Movements on Negative Autobiographical Memories.

    Science.gov (United States)

    Littel, Marianne; Kenemans, J Leon; Baas, Johanna M P; Logemann, H N Alexander; Rijken, Nellie; Remijn, Malou; Hassink, Rutger J; Engelhard, Iris M; van den Hout, Marcel A

    2017-10-15

    Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder. During EMDR, patients make horizontal eye movements (EMs) while simultaneously recalling a traumatic memory, which renders the memory less vivid and emotional when it is later recalled again. Recalling highly emotional autobiographical memories enhances noradrenergic neurotransmission. Noradrenaline (NA) strengthens memory (re)consolidation. However, memories become less vivid after recall+EMs. Therefore, NA might either play no significant role or serve to strengthen memories that are degraded by EMs. The present study was designed to test the latter hypothesis. We predicted that blocking NA would abolish the memory degrading effects of EMs. Fifty-six healthy participants selected three negative autobiographical memories. One was then recalled while making EMs, one was recalled without EMs, and one was not recalled. Vividness and emotionality of the memories as well as heart rate and skin conductance level during memory retrieval were measured before, directly after, and 24 hours after the EM task. Before the task, participants received a placebo or the noradrenergic β-receptor blocker propranolol (40 mg). There were no effects of EMs on memory emotionality or psychophysiological measures in the propranolol and placebo groups. However, in the placebo group, but not in the propranolol group, memory vividness significantly decreased from pretest to posttest and follow-up after recall+EMs relative to the control conditions. Blocking NA abolished the effects of EMs on the vividness of emotional memories, indicating that NA is crucial for EMDR effectiveness and possibly strengthens the reconsolidation of the degraded memory. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  2. Facilitative Effects of Forgetting from Short-Term Memory on Growth of Long-Term Memory in Retardates

    Science.gov (United States)

    Sperber, Richard D.

    1976-01-01

    Competing explanations of the beneficial effect of spacing in retardate discrimination learning were tested. Results are inconsistent with consolidation and rehearsal theories but support the prediction of the Geber, Greenfield, and House spacing model that forgetting from short-term memory facilities retardate learning. (Author/SB)

  3. The Effects of Intersensory Redundancy on Attention and Memory: Infants' Long-Term Memory for Orientation in Audiovisual Events

    Science.gov (United States)

    Flom, Ross; Bahrick, Lorraine E.

    2010-01-01

    This research examined the effects of bimodal audiovisual and unimodal visual stimulation on infants' memory for the visual orientation of a moving toy hammer following a 5-min, 2-week, or 1-month retention interval. According to the intersensory redundancy hypothesis (L. E. Bahrick & R. Lickliter, 2000; L. E. Bahrick, R. Lickliter, & R. Flom,…

  4. Exploring the effect of sleep and reduced interference on different forms of declarative memory.

    Science.gov (United States)

    Schönauer, Monika; Pawlizki, Annedore; Köck, Corinna; Gais, Steffen

    2014-12-01

    Many studies have found that sleep benefits declarative memory consolidation. However, fundamental questions on the specifics of this effect remain topics of discussion. It is not clear which forms of memory are affected by sleep and whether this beneficial effect is partly mediated by passive protection against interference. Moreover, a putative correlation between the structure of sleep and its memory-enhancing effects is still being discussed. In three experiments, we tested whether sleep differentially affects various forms of declarative memory. We varied verbal content (verbal/nonverbal), item type (single/associate), and recall mode (recall/recognition, cued/free recall) to examine the effect of sleep on specific memory subtypes. We compared within-subject differences in memory consolidation between intervals including sleep, active wakefulness, or quiet meditation, which reduced external as well as internal interference and rehearsal. Forty healthy adults aged 18-30 y, and 17 healthy adults aged 24-55 y with extensive meditation experience participated in the experiments. All types of memory were enhanced by sleep if the sample size provided sufficient statistical power. Smaller sample sizes showed an effect of sleep if a combined measure of different declarative memory scales was used. In a condition with reduced external and internal interference, performance was equal to one with high interference. Here, memory consolidation was significantly lower than in a sleep condition. We found no correlation between sleep structure and memory consolidation. Sleep does not preferentially consolidate a specific kind of declarative memory, but consistently promotes overall declarative memory formation. This effect is not mediated by reduced interference. © 2014 Associated Professional Sleep Societies, LLC.

  5. Working memory load eliminates the survival processing effect.

    Science.gov (United States)

    Kroneisen, Meike; Rummel, Jan; Erdfelder, Edgar

    2014-01-01

    In a series of experiments, Nairne, Thompson, and Pandeirada (2007) demonstrated that words judged for their relevance to a survival scenario are remembered better than words judged for a scenario not relevant on a survival dimension. They explained this survival-processing effect by arguing that nature "tuned" our memory systems to process and remember fitness-relevant information. Kroneisen and Erdfelder (2011) proposed that it may not be survival processing per se that facilitates recall but the richness and distinctiveness with which information is encoded. To further test this account, we investigated how the survival processing effect is affected by cognitive load. If the survival processing effect is due to automatic processes or, alternatively, if survival processing is routinely prioritized in dual-task contexts, we would expect this effect to persist under cognitive load conditions. If the effect relies on cognitively demanding processes like richness and distinctiveness of encoding, however, the survival processing benefit should be hampered by increased cognitive load during encoding. Results were in line with the latter prediction, that is, the survival processing effect vanished under dual-task conditions.

  6. Consolidation differentially modulates schema effects on memory for items and associations.

    Science.gov (United States)

    van Kesteren, Marlieke T R; Rijpkema, Mark; Ruiter, Dirk J; Fernández, Guillén

    2013-01-01

    Newly learned information that is congruent with a preexisting schema is often better remembered than information that is incongruent. This schema effect on memory has previously been associated to more efficient encoding and consolidation mechanisms. However, this effect is not always consistently supported in the literature, with differential schema effects reported for different types of memory, different retrieval cues, and the possibility of time-dependent effects related to consolidation processes. To examine these effects more directly, we tested participants on two different types of memory (item recognition and associative memory) for newly encoded visuo-tactile associations at different study-test intervals, thus probing memory retrieval accuracy for schema-congruent and schema-incongruent items and associations at different time points (t = 0, t = 20, and t = 48 hours) after encoding. Results show that the schema effect on visual item recognition only arises after consolidation, while the schema effect on associative memory is already apparent immediately after encoding, persisting, but getting smaller over time. These findings give further insight into different factors influencing the schema effect on memory, and can inform future schema experiments by illustrating the value of considering effects of memory type and consolidation on schema-modulated retrieval.

  7. Environmental context effects on episodic memory are dependent on retrieval mode and modulated by neuropsychological status.

    Science.gov (United States)

    Barak, Ohr; Vakil, Eli; Levy, Daniel A

    2013-01-01

    Contextual change or constancy between occasions of memory formation and retrieval are commonly assumed to affect retrieval success, yet such effects may be inconsistent, and the processes leading to the pattern of effects are still not well understood. We conducted a systematic investigation of environmental context effects on memory, using a range of materials (common objects, pictures of familiar and unfamiliar faces, words, and sentences), and four types of retrieval (free recall, cued recall, recognition, and order memory), all assessed within participants. Additionally, we examined the influence of mnemonic challenge on context effects by examining both healthy participants and a group of patients in rehabilitation following traumatic brain injury (TBI). We found no effects of contextual factors on tests of recognition for either group of participants, but effects did emerge for cued and free recall, with the most prominent effects being on memory for objects. Furthermore, while patients' memory abilities in general were impaired relative to the comparison group, they exhibited greater influences of contextual reinstatement on several recall tasks. These results support suggestions that environmental context effects on memory are dependent on retrieval mode and on the extent to which retrieval is challenging because of neurocognitive status. Additionally, findings of environmental context effects in memory-impaired TBI patients suggest that by harnessing such preserved indirect memory (e.g., using reminder technologies), it may be possible to ameliorate TBI patients' difficulties in explicit remembering.

  8. Consolidation differentially modulates schema effects on memory for items and associations.

    Directory of Open Access Journals (Sweden)

    Marlieke T R van Kesteren

    Full Text Available Newly learned information that is congruent with a preexisting schema is often better remembered than information that is incongruent. This schema effect on memory has previously been associated to more efficient encoding and consolidation mechanisms. However, this effect is not always consistently supported in the literature, with differential schema effects reported for different types of memory, different retrieval cues, and the possibility of time-dependent effects related to consolidation processes. To examine these effects more directly, we tested participants on two different types of memory (item recognition and associative memory for newly encoded visuo-tactile associations at different study-test intervals, thus probing memory retrieval accuracy for schema-congruent and schema-incongruent items and associations at different time points (t = 0, t = 20, and t = 48 hours after encoding. Results show that the schema effect on visual item recognition only arises after consolidation, while the schema effect on associative memory is already apparent immediately after encoding, persisting, but getting smaller over time. These findings give further insight into different factors influencing the schema effect on memory, and can inform future schema experiments by illustrating the value of considering effects of memory type and consolidation on schema-modulated retrieval.

  9. Modulatory mechanisms of cortisol effects on emotional learning and memory: novel perspectives.

    Science.gov (United States)

    van Ast, Vanessa A; Cornelisse, Sandra; Marin, Marie-France; Ackermann, Sandra; Garfinkel, Sarah N; Abercrombie, Heather C

    2013-09-01

    It has long been known that cortisol affects learning and memory processes. Despite a wealth of research dedicated to cortisol effects on learning and memory, the strength or even directionality of the effects often vary. A number of the factors that alter cortisol's effects on learning and memory are well-known. For instance, effects of cortisol can be modulated by emotional arousal and the memory phase under study. Despite great advances in understanding factors that explain variability in cortisol's effects, additional modulators of cortisol effects on memory exist that are less widely acknowledged in current basic experimental research. The goal of the current review is to disseminate knowledge regarding less well-known modulators of cortisol effects on learning and memory. Since several models for the etiology of anxiety, such as post-traumatic stress disorder (PTSD), incorporate stress and the concomitant release of cortisol as important vulnerability factors, enhanced understanding of mechanisms by which cortisol exerts beneficial as opposed to detrimental effects on memory is very important. Further elucidation of the factors that modulate (or alter) cortisol's effects on memory will allow reconciliation of seemingly inconsistent findings in the basic and clinical literatures. The present review is based on a symposium as part of the 42nd International Society of Psychoneuroendocrinology Conference, New York, USA, that highlighted some of those modulators and their underlying mechanisms. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Are addiction-related memories malleable by working memory competition? Transient effects on memory vividness and nicotine craving in a randomized lab experiment.

    Science.gov (United States)

    Markus, Wiebren; de Weert-van Oene, Gerdien H; Woud, Marcella L; Becker, Eni S; DeJong, Cornelis A J

    2016-09-01

    Experimental research suggests that working memory (WM) taxation reduces craving momentarily. Using a modified Eye Movement Desensitization and Reprocessing (EMDR) procedure, prolonged reductions in craving and relapse rates in alcohol dependence have been demonstrated. Modified EMDR-procedures may also hold promise in smoking cessation attempts. A proof-of-concept study was conducted to narrow the gap between WM-taxation experiments and clinical EMDR studies. To this end the clinical EMDR-procedure was modified for use in a laboratory experiment. Daily smokers (n = 47), abstaining overnight, were allocated (by minimization randomization) to one of two groups using a parallel design. In both cases a modified EMDR-procedure was used. In the experimental group (n = 24) eye movements (EM) were induced while control group participants (n = 23) fixed their gaze (not taxing WM). During 6 min trials, craving-inducing memories were recalled. Craving, vividness of target memories, and smoking behavior were assessed at several variable-specific time-points between baseline (one week pre-intervention) and one week follow-up. The experimental group showed significant immediate reductions of craving and vividness of targeted memories. However, these effects were lost during a one-week follow-up period. A limited dose of WM-taxation, in the form of EM in a modified EMDR-procedure, resulted in transient effects on memory vividness and nicotine craving. EM provide a valuable way of coping with the acute effects of craving during smoking cessation attempts. Other aspects of the EMDR-procedure may provide additional effects. Component and dose-response studies are needed to establish the potential of EMDR-therapy in smoking cessation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Contrasting Effects of Histone Deacetylase Inhibitors on Reward and Aversive Olfactory Memories in the Honey Bee

    Directory of Open Access Journals (Sweden)

    Gabrielle A Lockett

    2014-06-01

    Full Text Available Much of what we have learnt from rodent models about the essential role of epigenetic processes in brain plasticity has made use of aversive learning, yet the role of histone acetylation in aversive memory in the honey bee, a popular invertebrate model for both memory and epigenetics, was previously unknown. We examined the effects of histone deacetylase (HDAC inhibition on both aversive and reward olfactory associative learning in a discrimination proboscis extension reflex (PER assay. We report that treatment with the HDAC inhibitors APHA compound 8 (C8, phenylbutyrate (PB or sodium butyrate (NaB impaired discrimination memory due to impairment of aversive memory in a dose-dependent manner, while simultaneously having no effect on reward memory. Treatment with C8 1 h before training, 1 h after training or 1 h before testing, impaired aversive but not reward memory at test. C8 treatment 1 h before training also improved aversive but not reward learning during training. PB treatment only impaired aversive memory at test when administered 1 h after training, suggesting an effect on memory consolidation specifically. Specific impairment of aversive memory (but not reward memory by HDAC inhibiting compounds was robust, reproducible, occurred following treatment with three drugs targeting the same mechanism, and is likely to be genuinely due to alterations to memory as sucrose sensitivity and locomotion were unaffected by HDAC inhibitor treatment. This pharmacological dissection of memory highlights the involvement of histone acetylation in aversive memory in the honey bee, and expands our knowledge of epigenetic control of neural plasticity in invertebrates.

  12. Propranolol–induced Impairment of Contextual Fear Memory Reconsolidation in Rats: A similar Effect on Weak and Strong Recent and Remote Memories

    Science.gov (United States)

    Taherian, Fatemeh; Vafaei, Abbas Ali; Vaezi, Gholam Hassan; Eskandarian, Sharaf; Kashef, Adel; Rashidy-Pour, Ali

    2014-01-01

    Introduction Previous studies have demonstrated that the β-adrenergic receptor antagonist propranolol impairs fear memory reconsolidation in experimental animals. There are experimental parameters such as the age and the strength of memory that can interact with pharmacological manipulations of memory reconsolidation. In this study, we investigated the ability of the age and the strength of memory to influence the disrupting effects of propranolol on fear memory reconsolidation in rats. Methods The rats were trained in a contextual fear conditioning using two (weak training) or five (strong training) footshocks (1mA). Propranolol (10mg/kg) injection was immediately followed retrieval of either a one-day recent (weak or strong) or 36-day remote (weak or strong) contextual fear memories. Results We found that propranolol induced a long-lasting impairment of subsequent expression of recent and remote memories with either weak or strong strength. We also found no memory recovery after a weak reminder shock. Furthermore, no significant differences were found on the amount of memory deficit induced by propranolol among memories with different age and strength. Discussion Our data suggest that the efficacy of propranolol in impairing fear memory reconsolidation is not limited to the age or strength of the memory. PMID:25337385

  13. Effects of motor congruence on visual working memory.

    Science.gov (United States)

    Quak, Michel; Pecher, Diane; Zeelenberg, Rene

    2014-10-01

    Grounded-cognition theories suggest that memory shares processing resources with perception and action. The motor system could be used to help memorize visual objects. In two experiments, we tested the hypothesis that people use motor affordances to maintain object representations in working memory. Participants performed a working memory task on photographs of manipulable and nonmanipulable objects. The manipulable objects were objects that required either a precision grip (i.e., small items) or a power grip (i.e., large items) to use. A concurrent motor task that could be congruent or incongruent with the manipulable objects caused no difference in working memory performance relative to nonmanipulable objects. Moreover, the precision- or power-grip motor task did not affect memory performance on small and large items differently. These findings suggest that the motor system plays no part in visual working memory.

  14. The target effect: visual memory for unnamed search targets.

    Science.gov (United States)

    Thomas, Mark D; Williams, Carrick C

    2014-01-01

    Search targets are typically remembered much better than other objects even when they are viewed for less time. However, targets have two advantages that other objects in search displays do not have: They are identified categorically before the search, and finding them represents the goal of the search task. The current research investigated the contributions of both of these types of information to the long-term visual memory representations of search targets. Participants completed either a predefined search or a unique-object search in which targets were not defined with specific categorical labels before searching. Subsequent memory results indicated that search target memory was better than distractor memory even following ambiguously defined searches and when the distractors were viewed significantly longer. Superior target memory appears to result from a qualitatively different representation from those of distractor objects, indicating that decision processes influence visual memory.

  15. Effect of lead acetate on learning and memory in rats

    Energy Technology Data Exchange (ETDEWEB)

    Seki, H; Maeda, H; Ohi, G; Yagyu, H

    1974-01-01

    To study the mental effects of exposure to lead, especially in auto exhaust in the ambient air, adult female Wistar rats were orally dosed with lead acetate at 125 mg(Pb)/30 g food for 6 weeks from the 3rd day of pregnancy to the 3rd week after delivery. Nine week-old male rats were examined as to learning and memory ability using a labyrinth in comparison to the ability of control rats. No significant deterioration of these abilities which might have been caused by exposure to lead in the rats early life stage was noted, although the mothers were given the maximal dose of lead they and the fetuses could tolerate.

  16. Evolutive Masing model, cycling plasticity, ageing and memory effects

    International Nuclear Information System (INIS)

    Sidoroff, F.

    1987-01-01

    Many models are proposed for the mechanical description of the cyclic behaviour of metals and used for structure analysis under cyclic loading. The evolutive Masing model has been proposed (Fougeres, Sidoroff, Vincent and Waille 1985) to combine - the accuracy of hereditary models for the description of hysteresis on each cycle, - the versatility of internal variables for the state description and evolution, - a sufficient microstructural basis to make the interaction easier with microstructural investigations. The purpose of the present work is to discuss this model and to compare different evolution assumptions with respect to some memory effects (cyclic hardening and softening, multilevel tests, ageing). Attention is limited to uniaxial, rate independent elasto-plastic behaviour. (orig./GL)

  17. Significance of autobiographical episodes and spacing effects in incidental memory.

    Science.gov (United States)

    Toyota, Hiroshi

    2013-10-01

    Participants were presented with target words on two occasions, and were asked each time to generate a memory of a past episode associated with the targets. Participants were also instructed to rate the importance (significance elaboration) or pleasantness of the pisode (pleasantness elaboration) in an orienting task, followed by an unexpect d recall test. Significance elaboration led to better recall than pleasantness elaboration, but only in the spaced presentation. The spaced presentation led to better tree recall than massed presentation with significance elaboration, but the difference between the two types of presentation was not observed with pleasantness elaboration. These results suggest that the significance of an episode is more critical than the pleasantness of an episode in determining the effectiveness of autobiographical elaboration in facilitating recall.

  18. The Effect of Radiation "Memory" in Alkali-Halide Crystals

    Science.gov (United States)

    Korovkin, M. V.; Sal'nikov, V. N.

    2017-01-01

    The exposure of the alkali-halide crystals to ionizing radiation leads to the destruction of their structure, the emergence of radiation defects, and the formation of the electron and hole color centers. Destruction of the color centers upon heating is accompanied by the crystal bleaching, luminescence, and radio-frequency electromagnetic emission (REME). After complete thermal bleaching of the crystal, radiation defects are not completely annealed, as the electrons and holes released from the color centers by heating leave charged and locally uncompensated defects. Clusters of these "pre centers" lead to electric microheterogeneity of the crystal, the formation of a quasi-electret state, and the emergence of micro-discharges accompanied by radio emission. The generation of REME associated with residual defectiveness, is a manifestation of the effect of radiation "memory" in dielectrics.

  19. Memory effect of ball-milled and annealed nanosized hematite

    International Nuclear Information System (INIS)

    Bercoff, P.G.; Bertorello, H.R.; Oliva, M.I.

    2007-01-01

    Fine particles of hematite (mean size 55 nm) were produced by ball milling a mixture of hematite and pure Fe and annealing at 1000 o C. X-ray diffraction (XRD) and Moessbauer spectroscopy show that only α-Fe 2 O 3 is present in the final product, with lattice and Moessbauer parameters that correspond to bulk hematite. ZFC and FC magnetization measurements were performed from 5 to 300 K, at different applied fields. Two magnetic regimes were observed: one at low temperatures (≤100 K) that we ascribe to the magnetic moments in the outer shell of the particles that couple to the magnetic moments in the core, and another at higher temperature that corresponds to the Morin transition, finding that the Morin temperature is T M =246 K. The memory effect is clearly observed in magnetic measurements that start from different remanence states and explained as dependent on the ordering of the magnetic moments within the particles

  20. The effects of sleep restriction and sleep deprivation in producing false memories.

    Science.gov (United States)

    Chatburn, Alex; Kohler, Mark J; Payne, Jessica D; Drummond, Sean P A

    2017-01-01

    False memory has been claimed to be the result of an associative process of generalisation, as well as to be representative of memory errors. These can occur at any stage of memory encoding, consolidation, or retrieval, albeit through varied mechanisms. The aim of this paper is to experimentally determine: (i) if cognitive dysfunction brought about by sleep loss at the time of stimulus encoding can influence false memory production; and (ii) whether this relationship holds across sensory modalities. Subjects undertook both the Deese-Roedigger-McDermott (DRM) false memory task and a visual task designed to produce false memories. Performance was measured while subjects were well-rested (9h Time in Bed or TIB), and then again when subjects were either sleep restricted (4h TIB for 4 nights) or sleep deprived (30h total SD). Results indicate (1) that partial and total sleep loss produced equivalent effects in terms of false and veridical verbal memory, (2) that subjects performed worse after sleep loss (regardless of whether this was partial or total sleep loss) on cued recognition-based false and veridical verbal memory tasks, and that sleep loss interfered with subjects' ability to recall veridical, but not false memories under free recall conditions, and (3) that there were no effects of sleep loss on a visual false memory task. This is argued to represent the dysfunction and slow repair of an online verbal associative process in the brain following inadequate sleep. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Effects of Mineralocorticoid Receptors Blockade on FearMemory Reconsolidation in Rats

    Directory of Open Access Journals (Sweden)

    Abbas Ali Vafaei

    2011-08-01

    Full Text Available Reconsolidation memory is defined as a process in which the retrieval of a previously consolidated memory returns to a labile state which is then subject to stabilization. Previous studies have shown that mineralocorticoid receptors (MRs modulate distinct phases of learning and memory, which display a high concentration and distinct distribution in the hippocampus. Moreover, we found no studies that examined the role of hippocampal MRs in fear memory reconsolidation. Here, we investigated the effect of MRs blockade on fear memory reconsolidation in rats. Additionally, to test whether blockade of protein synthesis would disrupt fear memory reconsolidation in our paradigm, we tested the effect of cycloheximide, an inhibitor of protein synthesis after memory reactivation. Results indicated that systemic as well as intra-hippocampal administrations of the MR antagonist spironolactone immediately following memory reactivation did not affect on post-retrieval long-term memory. Cycloheximide given after the reactivation treatment produced a strong impairment that persisted over test sessions. These findings indicate that MRs are not required for reconsolidation of fear-based memory.

  2. The effects of sequential attention shifts within visual working memory

    Directory of Open Access Journals (Sweden)

    Qi eLi

    2014-09-01

    Full Text Available Previous studies have shown conflicting data as to whether it is possible to sequentially shift spatial attention among visual working memory (VWM representations. The present study investigated this issue by asynchronously presenting attentional cues during the retention interval of a change detection task. In particular, we focused on two types of sequential attention shifts: 1 orienting attention to one location, and then withdrawing attention from it, and 2 switching the focus of attention from one location to another. In Experiment 1, a withdrawal cue was presented after a spatial retro-cue to measure the effect of withdrawing attention. The withdrawal cue significantly reduced the cost of invalid spatial cues, but surprisingly, did not attenuate the benefit of valid spatial cues. This indicates that the withdrawal cue only triggered the activation of facilitative components but not inhibitory components of attention. In Experiment 2, two spatial retro-cues were presented successively to examine the effect of switching the focus of attention. We observed benefits of both the first and second cues in sequential cueing, indicating that participants were able to reorient attention from one location to another within VWM, and the reallocation of attention did not attenuate memory at the first cued location. In Experiment 3, we found that reducing the validity of the preceding spatial cue did lead to a significant reduction in its benefit. However, performance at the first-cued location was still better than the neutral baseline or performance at the uncued locations, indicating that the first cue benefit might have been preserved both partially under automatic control and partially under voluntary control. Our findings revealed new properties of dynamic attentional control in VWM maintenance.

  3. The effects of sequential attention shifts within visual working memory.

    Science.gov (United States)

    Li, Qi; Saiki, Jun

    2014-01-01

    Previous studies have shown conflicting data as to whether it is possible to sequentially shift spatial attention among visual working memory (VWM) representations. The present study investigated this issue by asynchronously presenting attentional cues during the retention interval of a change detection task. In particular, we focused on two types of sequential attention shifts: (1) orienting attention to one location, and then withdrawing attention from it, and (2) switching the focus of attention from one location to another. In Experiment 1, a withdrawal cue was presented after a spatial retro-cue to measure the effect of withdrawing attention. The withdrawal cue significantly reduced the cost of invalid spatial cues, but surprisingly, did not attenuate the benefit of valid spatial cues. This indicates that the withdrawal cue only triggered the activation of facilitative components but not inhibitory components of attention. In Experiment 2, two spatial retro-cues were presented successively to examine the effect of switching the focus of attention. We observed equivalent benefits of the first and second spatial cues, suggesting that participants were able to reorient attention from one location to another within VWM, and the reallocation of attention did not attenuate memory at the first-cued location. In Experiment 3, we found that reducing the validity of the preceding spatial cue did lead to a significant reduction in its benefit. However, performance was still better at first-cued locations than at uncued and neutral locations, indicating that the first cue benefit might have been preserved both partially under automatic control and partially under voluntary control. Our findings revealed new properties of dynamic attentional control in VWM maintenance.

  4. The effects of sequential attention shifts within visual working memory

    Science.gov (United States)

    Li, Qi; Saiki, Jun

    2014-01-01

    Previous studies have shown conflicting data as to whether it is possible to sequentially shift spatial attention among visual working memory (VWM) representations. The present study investigated this issue by asynchronously presenting attentional cues during the retention interval of a change detection task. In particular, we focused on two types of sequential attention shifts: (1) orienting attention to one location, and then withdrawing attention from it, and (2) switching the focus of attention from one location to another. In Experiment 1, a withdrawal cue was presented after a spatial retro-cue to measure the effect of withdrawing attention. The withdrawal cue significantly reduced the cost of invalid spatial cues, but surprisingly, did not attenuate the benefit of valid spatial cues. This indicates that the withdrawal cue only triggered the activation of facilitative components but not inhibitory components of attention. In Experiment 2, two spatial retro-cues were presented successively to examine the effect of switching the focus of attention. We observed equivalent benefits of the first and second spatial cues, suggesting that participants were able to reorient attention from one location to another within VWM, and the reallocation of attention did not attenuate memory at the first-cued location. In Experiment 3, we found that reducing the validity of the preceding spatial cue did lead to a significant reduction in its benefit. However, performance was still better at first-cued locations than at uncued and neutral locations, indicating that the first cue benefit might have been preserved both partially under automatic control and partially under voluntary control. Our findings revealed new properties of dynamic attentional control in VWM maintenance. PMID:25237306

  5. The Cambridge Car Memory Test: a task matched in format to the Cambridge Face Memory Test, with norms, reliability, sex differences, dissociations from face memory, and expertise effects.

    Science.gov (United States)

    Dennett, Hugh W; McKone, Elinor; Tavashmi, Raka; Hall, Ashleigh; Pidcock, Madeleine; Edwards, Mark; Duchaine, Bradley

    2012-06-01

    Many research questions require a within-class object recognition task matched for general cognitive requirements with a face recognition task. If the object task also has high internal reliability, it can improve accuracy and power in group analyses (e.g., mean inversion effects for faces vs. objects), individual-difference studies (e.g., correlations between certain perceptual abilities and face/object recognition), and case studies in neuropsychology (e.g., whether a prosopagnosic shows a face-specific or object-general deficit). Here, we present such a task. Our Cambridge Car Memory Test (CCMT) was matched in format to the established Cambridge Face Memory Test, requiring recognition of exemplars across view and lighting change. We tested 153 young adults (93 female). Results showed high reliability (Cronbach's alpha = .84) and a range of scores suitable both for normal-range individual-difference studies and, potentially, for diagnosis of impairment. The mean for males was much higher than the mean for females. We demonstrate independence between face memory and car memory (dissociation based on sex, plus a modest correlation between the two), including where participants have high relative expertise with cars. We also show that expertise with real car makes and models of the era used in the test significantly predicts CCMT performance. Surprisingly, however, regression analyses imply that there is an effect of sex per se on the CCMT that is not attributable to a stereotypical male advantage in car expertise.

  6. On the effect of memory in a quantum prisoner's dilemma cellular automaton

    Science.gov (United States)

    Alonso-Sanz, Ramón; Revuelta, Fabio

    2018-03-01

    The disrupting effect of quantum memory on the dynamics of a spatial quantum formulation of the iterated prisoner's dilemma game with variable entangling is studied. The game is played within a cellular automata framework, i.e., with local and synchronous interactions. The main findings of this work refer to the shrinking effect of memory on the disruption induced by noise.

  7. Shape memory effect of Fe-14% Mn-6% Si-9% Cr-6% Ni alloy polycrystals

    International Nuclear Information System (INIS)

    Inagaki, Hirosuke

    1992-01-01

    Factors affecting the shape memory effect in Fe-14% Mn-6% Si-9% Cr-6% Ni alloy polycrystals were studied in detail. It was found that the shape memory effect in this alloy was most influenced by the amount of deformation. With increasing amount of deformation, the shape memory effect diminished appreciably. Although the fraction of the initial dimensional change that could be restored was about 45% in the specimen strained by 4%, only 21% of the initial dimensional change was recovered in the specimen strained by 9%. Temperatures of deformation were found to be also an important factor that affected the shape memory effect. The maximum shape memory effect was observed in the specimens strained at temperatures between the M s and M d temperatures. In this alloy, however, specimens strained at temperatures below the M s temperature indicated a relatively large shape memory effect, too. It was further found that the shape memory effect was appreciably intensified by repeated straining and annealing, especially when straining was performed at 500deg C. It was suggested that the shape memory effect in Fe base alloys was strongly influenced by the dislocation substructure present in the starting material. (orig.) [de

  8. The relationship of intelligence and memory to interrogative suggestibility: the importance of range effects.

    Science.gov (United States)

    Gudjonsson, G H

    1988-05-01

    This paper looks at the relationship between intelligence, memory and interrogative suggestibility, particularly with reference to range effects. The subjects were 60 normal subjects and 100 forensic patients who had completed the Gudjonsson Suggestibility Scale (GSS) and the Wechsler Adult Intelligence Scale. Clear range effects of IQ and memory were evident in their relationship with suggestibility.

  9. The effect of self-reported habitual sleep quality and sleep length on autobiographical memory

    NARCIS (Netherlands)

    Murre, J.M.J.; Kristo, G.; Janssen, S.M.J.

    2014-01-01

    A large number of studies have recently shown effects of sleep on memory consolidation. In this study the effects of the sleep quality and sleep length on the retention of autobiographical memories are examined, using an Internet-based diary technique (Kristo, Janssen, & Murre, 2009). Each of over

  10. Ferroelectric-gate field effect transistor memories device physics and applications

    CERN Document Server

    Ishiwara, Hiroshi; Okuyama, Masanori; Sakai, Shigeki; Yoon, Sung-Min

    2016-01-01

    This book provides comprehensive coverage of the materials characteristics, process technologies, and device operations for memory field-effect transistors employing inorganic or organic ferroelectric thin films. This transistor-type ferroelectric memory has interesting fundamental device physics and potentially large industrial impact. Among the various applications of ferroelectric thin films, the development of nonvolatile ferroelectric random access memory (FeRAM) has progressed most actively since the late 1980s and has achieved modest mass production levels for specific applications since 1995. There are two types of memory cells in ferroelectric nonvolatile memories. One is the capacitor-type FeRAM and the other is the field-effect transistor (FET)-type FeRAM. Although the FET-type FeRAM claims ultimate scalability and nondestructive readout characteristics, the capacitor-type FeRAMs have been the main interest for the major semiconductor memory companies, because the ferroelectric FET has fatal handic...

  11. `Unlearning' has a stabilizing effect in collective memories

    Science.gov (United States)

    Hopfield, J. J.; Feinstein, D. I.; Palmer, R. G.

    1983-07-01

    Crick and Mitchison1 have presented a hypothesis for the functional role of dream sleep involving an `unlearning' process. We have independently carried out mathematical and computer modelling of learning and `unlearning' in a collective neural network of 30-1,000 neurones. The model network has a content-addressable memory or `associative memory' which allows it to learn and store many memories. A particular memory can be evoked in its entirety when the network is stimulated by any adequate-sized subpart of the information of that memory2. But different memories of the same size are not equally easy to recall. Also, when memories are learned, spurious memories are also created and can also be evoked. Applying an `unlearning' process, similar to the learning processes but with a reversed sign and starting from a noise input, enhances the performance of the network in accessing real memories and in minimizing spurious ones. Although our model was not motivated by higher nervous function, our system displays behaviours which are strikingly parallel to those needed for the hypothesized role of `unlearning' in rapid eye movement (REM) sleep.

  12. Bilateral and unilateral ECT: effects on verbal and nonverbal memory.

    Science.gov (United States)

    Squire, S R; Slater, P C

    1978-11-01

    The memory loss associated with bilateral and nondominant unilateral ECT was assessed with verbal memory tests known to be sensitive to left temporal lobe dysfunction and with nonverbal memory tests known to be sensitive to right temporal lobe dysfunction. Bilateral ECT markedly impaired delayed retention of verbal and nonverbal material. Right unilateral ECT impaired delayed retention of nonverbal material without measurably affecting retention of verbal material. Nonverbal memory was affected less by right unilateral ECT than by bilateral ECT. These findings, taken together with a consideration of the clinical efficacy of the two types of treatment, make what appears to be a conclusive case for unilateral over bilateral ECT.

  13. Retrieval of bilingual autobiographical memories: effects of cue language and cue imageability.

    Science.gov (United States)

    Mortensen, Linda; Berntsen, Dorthe; Bohn, Ocke-Schwen

    2015-01-01

    An important issue in theories of bilingual autobiographical memory is whether linguistically encoded memories are represented in language-specific stores or in a common language-independent store. Previous research has found that autobiographical memory retrieval is facilitated when the language of the cue is the same as the language of encoding, consistent with language-specific memory stores. The present study examined whether this language congruency effect is influenced by cue imageability. Danish-English bilinguals retrieved autobiographical memories in response to Danish and English high- or low-imageability cues. Retrieval latencies were shorter to Danish than English cues and shorter to high- than low-imageability cues. Importantly, the cue language effect was stronger for low-than high-imageability cues. To examine the relationship between cue language and the language of internal retrieval, participants identified the language in which the memories were internally retrieved. More memories were retrieved when the cue language was the same as the internal language than when the cue was in the other language, and more memories were identified as being internally retrieved in Danish than English, regardless of the cue language. These results provide further evidence for language congruency effects in bilingual memory and suggest that this effect is influenced by cue imageability.

  14. Effects of Intranasal Oxytocin on Long-Term Memory in Healthy Humans: A Systematic Review.

    Science.gov (United States)

    Brambilla, Michela; Manenti, Rosa; de Girolamo, Giovanni; Adenzato, Mauro; Bocchio-Chiavetto, Luisella; Cotelli, Maria

    2016-12-01

    Preclinical Research The neuropeptide oxytocin (Oxt) is implicated in complex emotional and social behaviors and appears to play an important role in learning and memory. Animal studies have shown that the effects of exogenous Oxt on memory vary according to the timing of administration, context, gender, and dose and may improve the memory of social, but not nonsocial stimuli. Oxt is intimately involved in a broad array of neuropsychiatric functions and may therefore be a pharmacological target for several psychiatric disorders. This review summarizes the potential effects of Oxt on long-term memory processes in healthy humans based on a PubMed search over the period 1980-2016. The effects of intranasal Oxt on human memory are controversial and the studies included in this review have applied a variety of learning paradigms, in turn producing variable outcomes. Specifically, data on the long-term memory of nonemotional stimuli found no effect or even worsening in memory, while studies using emotional stimuli showed an improvement of long-term memory performance. In conclusion, this review identified a link between long-term memory performance and exogenous intranasal Oxt in humans, although these results still warrant further confirmation in large, multicenter randomized controlled trials. Drug Dev Res 77 : 479-488, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Word frequency influences on the list length effect and associative memory in young and older adults.

    Science.gov (United States)

    Badham, Stephen P; Whitney, Cora; Sanghera, Sumeet; Maylor, Elizabeth A

    2017-07-01

    Many studies show that age deficits in memory are smaller for information supported by pre-experimental experience. Many studies also find dissociations in memory tasks between words that occur with high and low frequencies in language, but the literature is mixed regarding the extent of word frequency effects in normal ageing. We examined whether age deficits in episodic memory could be influenced by manipulations of word frequency. In Experiment 1, young and older adults studied short and long lists of high- and low-frequency words for free recall. The list length effect (the drop in proportion recalled for longer lists) was larger in young compared to older adults and for high- compared to low-frequency words. In Experiment 2, young and older adults completed item and associative recognition memory tests with high- and low-frequency words. Age deficits were greater for associative memory than for item memory, demonstrating an age-related associative deficit. High-frequency words led to better associative memory performance whilst low-frequency words resulted in better item memory performance. In neither experiment was there any evidence for age deficits to be smaller for high- relative to low-frequency words, suggesting that word frequency effects on memory operate independently from effects due to cognitive ageing.

  16. Effects of Transcranial Direct Current Stimulation (tDCS) on Human Memory.

    Energy Technology Data Exchange (ETDEWEB)

    Matzen, Laura E.; Trumbo, Michael Christopher Stefan

    2014-10-01

    Training a person in a new knowledge base or skill set is extremely time consuming and costly, particularly in highly specialized domains such as the military and the intelligence community. Recent research in cognitive neuroscience has suggested that a technique called transcranial direct current stimulation (tDCS) has the potential to revolutionize training by enabling learners to acquire new skills faster, more efficiently, and more robustly (Bullard et al., 2011). In this project, we tested the effects of tDCS on two types of memory performance that are critical for learning new skills: associative memory and working memory. Associative memory is memory for the relationship between two items or events. It forms the foundation of all episodic memories, so enhancing associative memory could provide substantial benefits to the speed and robustness of learning new information. We tested the effects of tDCS on associative memory, using a real-world associative memory task: remembering the links between faces and names. Working memory refers to the amount of information that can be held in mind and processed at one time, and it forms the basis for all higher-level cognitive processing. We investigated the degree of transfer between various working memory tasks (the N-back task as a measure of verbal working memory, the rotation-span task as a measure of visuospatial working memory, and Raven's progressive matrices as a measure of fluid intelligence) in order to determine if tDCS-induced facilitation of performance is task-specific or general.

  17. Word frequency influences on the list length effect and associative memory in young and older adults

    OpenAIRE

    Badham, SP; Whitney, C; Sanghera, S; Maylor, EA

    2016-01-01

    Many studies show that age deficits in memory are smaller for information supported by pre-experimental experience. Many studies also find dissociations in memory tasks between words that occur with high and low frequencies in language, but the literature is mixed regarding the extent of word frequency effects in normal ageing. We examined whether age deficits in episodic memory could be influenced by manipulations of word frequency. In Experiment 1, young and older adults studied short and l...

  18. Effectiveness of follow-up reminiscence therapy on autobiographical memory in pathological ageing.

    Science.gov (United States)

    Melendez, Juan C; Torres, Marta; Redondo, Rita; Mayordomo, Teresa; Sales, Alicia

    2017-08-01

    The objective is to examine the effects of reminiscence therapy (RT) on total, episodic and semantic autobiographical memory in amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) groups, testing the effects of RT on different stages of autobiographical memory, and its effectiveness at follow-up. A sample composed of 43 aMCI (27 treatments, 16 controls) and 30 AD (15 treatments, 15 controls) subjects were evaluated with the Autobiographical Memory Interview (AMI) test. The RT consisted of 10 sessions lasting 60 minutes each. Both groups, aMCI and AD, showed significant effects on overall autobiographical memory; aMCI showed significant main effects on episodic and semantic autobiographical memory in the treatment group, increasing scores in both cases. For AD, significant effects were observed on autobiographical episodic memory, showing an increase in the treatment group from Time 1 to follow-up; semantic memory showed a decrease in the control group from Time 1 to follow-up. Results show that RT implementation and follow-up are effective in increasing autobiographical memory in subjects with aMCI and AD. © 2015 International Union of Psychological Science.

  19. Memory Effects and Coverage Dependence of Surface Diffusion in a Model Adsorption System

    DEFF Research Database (Denmark)

    Vattulainen, Ilpo Tapio; Ying, S. C.; Ala-Nissila, T.

    1999-01-01

    in tracer and collective diffusion. We show that memory effects can be very pronounced deep inside the ordered phases and in regions close to first and second order phase transition boundaries. Particular attention is paid to the details of the time dependence of memory effects. The memory effect in tracer......We study the coverage dependence of surface diffusion coefficients for a strongly interacting adsorption system O/W(110) via Monte Carlo simulations of a lattice-gas model. In particular, we consider the nature and emergence of memory effects as contained in the corresponding correlation factors...... diffusion is found to decay following a power law after an initial transient period. This behavior persists until the hydrodynamic regime is reached, after which the memory effect decays exponentially. The time required to reach the hydrodynamical regime and the related exponential decay is strongly...

  20. Auditory and Visual Memories in PTSD Patients Targeted with Eye Movements and Counting: The Effect of Modality-Specific Loading of Working Memory

    Directory of Open Access Journals (Sweden)

    Suzy J. M. A. Matthijssen

    2017-11-01

    Full Text Available Introduction: Eye movement desensitization and reprocessing (EMDR therapy is an evidence-based treatment for post-traumatic stress disorder (PTSD. A key element of this therapy is simultaneously recalling an emotionally disturbing memory and performing a dual task that loads working memory. Memories targeted with this therapy are mainly visual, though there is some evidence that auditory memories can also be targeted.Objective: The present study tested whether auditory memories can be targeted with EMDR in PTSD patients. A second objective was to test whether taxing the patient (performing a dual task while recalling a memory in a modality specific way (auditory demanding for auditory memories and visually demanding for visual memories was more effective in reducing the emotionality experienced than taxing in cross-modality.Methods: Thirty-six patients diagnosed with PTSD were asked to recall two disturbing memories, one mainly visual, the other one mainly auditory. They rated the emotionality of the memories before being exposed to any condition. Both memories were then recalled under three alternating conditions [visual taxation, auditory taxation, and a control condition (CC, which comprised staring a non-moving dot] – counterbalanced in order – and patients rerated emotionality after each condition.Results: All three conditions were equally effective in reducing the emotionality of the auditory memory. Auditory loading was more effective in reducing the emotionality in the visual intrusion than the CC, but did not differ from the visual load.Conclusion: Auditory and visual aversive memories were less emotional after working memory taxation (WMT. This has some clinical implications for EMDR therapy, where mainly visual intrusions are targeted. In this study, there was no benefit of modality specificity. Further fundamental research should be conducted to specify the best protocol for WMT.

  1. Auditory and Visual Memories in PTSD Patients Targeted with Eye Movements and Counting: The Effect of Modality-Specific Loading of Working Memory.

    Science.gov (United States)

    Matthijssen, Suzy J M A; Verhoeven, Liselotte C M; van den Hout, Marcel A; Heitland, Ivo

    2017-01-01

    Introduction: Eye movement desensitization and reprocessing (EMDR) therapy is an evidence-based treatment for post-traumatic stress disorder (PTSD). A key element of this therapy is simultaneously recalling an emotionally disturbing memory and performing a dual task that loads working memory. Memories targeted with this therapy are mainly visual, though there is some evidence that auditory memories can also be targeted. Objective: The present study tested whether auditory memories can be targeted with EMDR in PTSD patients. A second objective was to test whether taxing the patient (performing a dual task while recalling a memory) in a modality specific way (auditory demanding for auditory memories and visually demanding for visual memories) was more effective in reducing the emotionality experienced than taxing in cross-modality. Methods: Thirty-six patients diagnosed with PTSD were asked to recall two disturbing memories, one mainly visual, the other one mainly auditory. They rated the emotionality of the memories before being exposed to any condition. Both memories were then recalled under three alternating conditions [visual taxation, auditory taxation, and a control condition (CC), which comprised staring a non-moving dot] - counterbalanced in order - and patients rerated emotionality after each condition. Results: All three conditions were equally effective in reducing the emotionality of the auditory memory. Auditory loading was more effective in reducing the emotionality in the visual intrusion than the CC, but did not differ from the visual load. Conclusion: Auditory and visual aversive memories were less emotional after working memory taxation (WMT). This has some clinical implications for EMDR therapy, where mainly visual intrusions are targeted. In this study, there was no benefit of modality specificity. Further fundamental research should be conducted to specify the best protocol for WMT.

  2. Temporal grouping effects in musical short-term memory.

    Science.gov (United States)

    Gorin, Simon; Mengal, Pierre; Majerus, Steve

    2018-07-01

    Recent theoretical accounts of verbal and visuo-spatial short-term memory (STM) have proposed the existence of domain-general mechanisms for the maintenance of serial order information. These accounts are based on the observation of similar behavioural effects across several modalities, such as temporal grouping effects. Across two experiments, the present study aimed at extending these findings, by exploring a STM modality that has received little interest so far, STM for musical information. Given its inherent rhythmic, temporal and serial organisation, the musical domain is of interest for investigating serial order STM processes such as temporal grouping. In Experiment 1, the data did not allow to determine the presence or the absence of temporal grouping effects. In Experiment 2, we observed that temporal grouping of tone sequences during encoding improves short-term recognition for serially presented probe tones. Furthermore, the serial position curves included micro-primacy and micro-recency effects, which are the hallmark characteristic of temporal grouping. Our results suggest that the encoding of serial order information in musical STM may be supported by temporal positional coding mechanisms similar to those reported in the verbal domain.

  3. The effects of study task on prestimulus subsequent memory effects in the hippocampus.

    Science.gov (United States)

    de Chastelaine, Marianne; Rugg, Michael D

    2015-11-01

    Functional magnetic resonance imaging (fMRI) was employed to examine the effects of a study task manipulation on pre-stimulus activity in the hippocampus predictive of later successful recollection. Eighteen young participants were scanned while making either animacy or syllable judgments on visually presented study words. Cues presented before each word denoted which judgment should be made. Following the study phase, a surprise recognition memory test was administered in which each test item had to be endorsed as "Remembered," "Known," or "New." As expected, "deep" animacy judgments led to better memory for study items than did "shallow" syllable judgments. In both study tasks, pre-stimulus subsequent recollection effects were evident in the interval between the cue and the study item in bilateral anterior hippocampus. However, the direction of the effects differed according to the study task: whereas pre-stimulus hippocampal activity on animacy trials was greater for later recollected items than items judged old on the basis of familiarity (replicating prior findings), these effects reversed for syllable trials. We propose that the direction of pre-stimulus hippocampal subsequent memory effects depends on whether an optimal pre-stimulus task set facilitates study processing that is conducive or unconducive to the formation of contextually rich episodic memories. © 2015 Wiley Periodicals, Inc.

  4. Methylprednisolone as a memory enhancer in rats: Effects on aversive memory, long-term potentiation and calcium influx.

    Science.gov (United States)

    de Vargas, Liane da Silva; Gonçalves, Rithiele; Lara, Marcus Vinícius S; Costa-Ferro, Zaquer S M; Salamoni, Simone Denise; Domingues, Michelle Flores; Piovesan, Angela Regina; de Assis, Dênis Reis; Vinade, Lucia; Corrado, Alexandre P; Alves-Do-Prado, Wilson; Correia-de-Sá, Paulo; da Costa, Jaderson Costa; Izquierdo, Ivan; Dal Belo, Cháriston A; Mello-Carpes, Pâmela B

    2017-09-01

    It is well recognized that stress or glucocorticoids hormones treatment can modulate memory performance in both directions, either impairing or enhancing it. Despite the high number of studies aiming at explaining the effects of glucocorticoids on memory, this has not yet been completely elucidated. Here, we demonstrate that a low daily dose of methylprednisolone (MP, 5mg/kg, i.p.) administered for 10-days favors aversive memory persistence in adult rats, without any effect on the exploring behavior, locomotor activity, anxiety levels and pain perception. Enhanced performance on the inhibitory avoidance task was correlated with long-term potentiation (LTP), a phenomenon that was strengthen in hippocampal slices of rats injected with MP (5mg/kg) during 10days. Additionally, in vitro incubation with MP (30-300µM) concentration-dependently increased intracellular [Ca 2+ ] i in cultured hippocampal neurons depolarized by KCl (35mM). In conclusion, a low daily dose of MP for 10days may promote aversive memory persistence in rats. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. The effect of electroconvulsive therapy on autobiographical memory: a systematic review.

    Science.gov (United States)

    Fraser, Louisa M; O'Carroll, Ronan E; Ebmeier, Klaus P

    2008-03-01

    In the last 20 years, an increasing number of articles have been published about effects of electroconvulsive therapy (ECT) on memory. Here, we review autobiographical memory studies in particular because there have been conflicting reports about the extent and persistence of ECT effects and the period before treatment from which memories are most likely to be affected. Five psychological and medical databases (MEDLINE, PubMed, PsychINFO, ScienceDirect, and Web of Knowledge) were searched from 1980 to 2007, yielding 15 studies of ECT and autobiographical memory. Evidence suggests that autobiographical memory impairment does occur as a result of ECT. Objective measures found memory loss to be relatively short term (6 months post-ECT). Electroconvulsive therapy predominantly affects memory of prior personal events that are near the treatment (within 6 months). Autobiographical memory loss is reduced by using brief pulse ECT rather than sine wave-unilateral positioning of electrodes rather than bilateral-and by titrating electrical current relative to the patient's own seizure threshold. Further research is required to determine memory loss associated with ECT, controlling for the direct effects of the depressive state.

  6. Testing the effectiveness of group-based memory rehabilitation in chronic stroke patients.

    Science.gov (United States)

    Miller, Laurie A; Radford, Kylie

    2014-01-01

    Memory complaints are common after stroke, yet there have been very few studies of the outcome of memory rehabilitation in these patients. The present study evaluated the effectiveness of a new manualised, group-based memory training programme. Forty outpatients with a single-stroke history and ongoing memory complaints were enrolled. The six-week course involved education and strategy training and was evaluated using a wait-list crossover design, with three assessments conducted 12 weeks apart. Outcome measures included: tests of anterograde memory (Rey Auditory Verbal Learning Test: RAVLT; Complex Figure Test) and prospective memory (Royal Prince Alfred Prospective Memory Test); the Comprehensive Assessment of Prospective Memory (CAPM) questionnaire and self-report of number of strategies used. Significant training-related gains were found on RAVLT learning and delayed recall and on CAPM informant report. Lower baseline scores predicted greater gains for several outcome measures. Patients with higher IQ or level of education showed more gains in number of strategies used. Shorter time since onset was related to gains in prospective memory, but no other stroke-related variables influenced outcome. Our study provides evidence that a relatively brief, group-based training intervention can improve memory functioning in chronic stroke patients and clarified some of the baseline factors that influence outcome.

  7. No Acute Effects of Choline Bitartrate Food Supplements on Memory in Healthy, Young, Human Adults.

    Science.gov (United States)

    Lippelt, D P; van der Kint, S; van Herk, K; Naber, M

    2016-01-01

    Choline is a dietary component and precursor of acetylcholine, a crucial neurotransmitter for memory-related brain functions. In two double-blind, placebo-controlled cross-over experiments, we investigated whether the food supplement choline bitartrate improved declarative memory and working memory in healthy, young students one to two hours after supplementation. In experiment 1, 28 participants performed a visuospatial working memory task. In experiment 2, 26 participants performed a declarative picture memorization task. In experiment 3, 40 participants performed a verbal working memory task in addition to the visuospatial working memory and declarative picture task. All tasks were conducted approximately 60 minutes after the ingestion of 2.0-2.5g of either choline bitartrate or placebo. We found that choline did not significantly enhance memory performance during any of the tasks. The null hypothesis that choline does not improve memory performance as compared to placebo was strongly supported by Bayesian statistics. These results are in contrast with animal studies suggesting that choline supplementation boosts memory performance and learning. We conclude that choline likely has no acute effects on cholinergic memory functions in healthy human participants.

  8. Reinstatement versus Reactivation Effects on Active Memory in Infants.

    Science.gov (United States)

    Adler, Scott A.; Rovee-Collier, Carolyn; Wilk, Amy

    2000-01-01

    Four experiments examined whether reinstatement and reactivation reminder paradigms affected memory performance of 102 three-month-olds. Results indicated that a single reinstatement protracted retention twice as long after training as a single reactivation. The novelty of the reminder stimulus also affected duration and specificity of memory in…

  9. Imaging stress effects on memory: a review of neuroimaging studies

    NARCIS (Netherlands)

    van Stegeren, A.H.

    2009-01-01

    Objective: To review and give an overview of neuroimaging studies that look at the role of stress (hormones) on memory. Method: An overview will be given of imaging studies that looked at the role of stress (hormones) on memory. Stress is here defined as the acute provocation of the sympathetic

  10. The effect of cue content on retrieval from autobiographical memory.

    Science.gov (United States)

    Uzer, Tugba; Brown, Norman R

    2017-01-01

    It has long been argued that personal memories are usually generated in an effortful search process in word-cueing studies. However, recent research (Uzer, Lee, & Brown, 2012) shows that direct retrieval of autobiographical memories, in response to word cues, is common. This invites the question of whether direct retrieval phenomenon is generalizable beyond the standard laboratory paradigm. Here we investigated prevalence of direct retrieval of autobiographical memories cued by specific and individuated cues versus generic cues. In Experiment 1, participants retrieved memories in response to cues from their own life (e.g., the names of friends) and generic words (e.g., chair). In Experiment 2, participants provided their personal cues two or three months prior to coming to the lab (min: 75days; max: 100days). In each experiment, RT was measured and participants reported whether memories were directly retrieved or generated on each trial. Results showed that personal cues elicited a high rate of direct retrieval. Personal cues were more likely to elicit direct retrieval than generic word cues, and as a consequence, participants responded faster, on average, to the former than to the latter. These results challenge the constructive view of autobiographical memory and suggest that autobiographical memories consist of pre-stored event representations, which are largely governed by associative mechanisms. These demonstrations offer theoretically interesting questions such as why are we not overwhelmed with directly retrieved memories cued by everyday familiar surroundings? Copyright © 2016 Elsevier B.V. All rights reserved.

  11. The Effect of Memory Trace Strength on Suggestibility.

    Science.gov (United States)

    Pezdek, Kathy; Roe, Chantal

    1995-01-01

    Examined the conditions under which children's memory is resistant to suggestibility versus vulnerable to suggestibility. Results suggest that children have more accurate memory for an event that occurred to them frequently, and that they are less vulnerable to suggestive influences such as biased interviewing procedures than they would be for an…

  12. Effects of Serial Rehearsal Training on Memory Search

    Science.gov (United States)

    McCauley, Charley; And Others

    1976-01-01

    Half the subjects were trained to use a serial rehearsal strategy during target set storage and half were given no strategy training. The results indicate that the rate of memory search is IQ-related, and that serial rehearsal training facilitates memory search when rehearsal is covert. (Author/BW)

  13. Acute Effects of Ecstasy on Memory Are more Extensive than Chronic Effects.

    Science.gov (United States)

    Shariati, Mohamad Bakhtiar Hesam; Sohrabi, Maryam; Shahidi, Siamak; Nikkhah, Ali; Mirzaei, Fatemeh; Medizadeh, Mehdi; Asl, Sara Soleimani

    2014-01-01

    Exposure to 3, 4- methylenedioxymethamphetamine (MDMA) could lead to serotonergic system toxicity in the brain. This system is responsible for learning and memory functions. Studies show that MDMA causes memory impairment dose-dependently and acutely. The present study was designed to evaluate the chronic and acute effects of MDMD on spatial memory and acquisition of passive avoidance. Adult male Wistar rats (200-250 g) were given single or multiple injections of MDMA (10 mg/kg, IP). Using passive avoidance and Morris Water Maze (MWM) tasks, learning and spatial memory functions were assessed. The data were analyzed by SPSS 16 software and one- way analysis of variance (ANOVA) test. Our results showed that there were significant differences in latency to enter the dark compartment (STL) between sham and MDMA- treated groups. Acute group significantly showed more STL in comparison with chronic group. Furthermore, MDMA groups spent more time in dark compartment (TDS) than the sham group. Administration of single dose of MDMA significantly caused an increase in TDS compared with the chronic group. In the MWM, MDMA treatment significantly increased the traveled distance and escaped latency compared to the sham group. Like to passive avoidance task, percentage of time spent in the target quadrant in MDMA- treated animals impaired in MWM compared with sham group. These data suggest that MDMA treatment impairs learning and memory functions that are more extensive in acute- treated rats.

  14. Acute Effects of Ecstasy on Memory Are more Extensive than Chronic Effects

    Directory of Open Access Journals (Sweden)

    Mohamad Bakhtiar Hesam Shariati

    2014-07-01

    Full Text Available Introduction: Exposure to 3, 4- methylenedioxymethamphetamine (MDMA could lead to serotonergic system toxicity in the brain. This system is responsible for learning and memory functions. Studies show that MDMA causes memory impairment dose-dependently and acutely. The present study was designed to evaluate the chronic and acute effects of MDMD on spatial memory and acquisition of passive avoidance. Methods: Adult male Wistar rats (200-250 g were given single or multiple injections of MDMA (10 mg/kg, IP. Using passive avoidance and Morris Water Maze (MWM tasks, learning and spatial memory functions were assessed. The data were analyzed by SPSS 16 software and one- way analysis of variance (ANOVA test. Results: Our results showed that there were significant differences in latency to enter the dark compartment (STL between sham and MDMA- treated groups. Acute group significantly showed more STL in comparison with chronic group. Furthermore, MDMA groups spent more time in dark compartment (TDS than the sham group. Administration of single dose of MDMA significantly caused an increase in TDS compared with the chronic group. In the MWM, MDMA treatment significantly increased the traveled distance and escaped latency compared to the sham group. Like to passive avoidance task, percentage of time spent in the target quadrant in MDMA- treated animals impaired in MWM compared with sham group. Discussion: These data suggest that MDMA treatment impairs learning and memory functions that are more extensive in acute- treated rats.

  15. The effects of glucose dose and dual-task performance on memory for emotional material.

    Science.gov (United States)

    Brandt, Karen R; Sünram-Lea, Sandra I; Jenkinson, Paul M; Jones, Emma

    2010-07-29

    Whilst previous research has shown that glucose administration can boost memory performance, research investigating the effects of glucose on memory for emotional material has produced mixed findings. Whereas some research has shown that glucose impairs memory for emotional material, other research has shown that glucose has no effect on emotional items. The aim of the present research was therefore to provide further investigation of the role of glucose on the recognition of words with emotional valence by exploring effects of dose and dual-task performance, both of which affect glucose facilitation effects. The results replicated past research in showing that glucose administration, regardless of dose or dual-task conditions, did not affect the memorial advantage enjoyed by emotional material. This therefore suggests an independent relationship between blood glucose levels and memory for emotional material. Copyright 2010 Elsevier B.V. All rights reserved.

  16. Selective attention meets spontaneous recognition memory: Evidence for effects at retrieval.

    Science.gov (United States)

    Moen, Katherine C; Miller, Jeremy K; Lloyd, Marianne E

    2017-03-01

    Previous research on the effects of Divided Attention on recognition memory have shown consistent impairments during encoding but more variable effects at retrieval. The present study explored whether effects of Selective Attention at retrieval and subsequent testing were parallel to those of Divided Attention. Participants studied a list of pictures and then had a recognition memory test that included both full attention and selective attention (the to be responded to object was overlaid atop a blue outlined object) trials. All participants then completed a second recognition memory test. The results of 2 experiments suggest that subsequent tests consistently show impacts of the status of the ignored stimulus, and that having an initial test changes performance on a later test. The results are discussed in relation to effect of attention on memory more generally as well as spontaneous recognition memory research. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Tactile Ranschburg effects: facilitation and inhibitory repetition effects analogous to verbal memory.

    Science.gov (United States)

    Roe, Daisy; Miles, Christopher; Johnson, Andrew J

    2017-07-01

    The present paper examines the effect of within-sequence item repetitions in tactile order memory. Employing an immediate serial recall procedure, participants reconstructed a six-item sequence tapped upon their fingers by moving those fingers in the order of original stimulation. In Experiment 1a, within-sequence repetition of an item separated by two-intervening items resulted in a significant reduction in recall accuracy for that repeated item (i.e., the Ranschburg effect). In Experiment 1b, within-sequence repetition of an adjacent item resulted in significant recall facilitation for that repeated item. These effects mirror those reported for verbal stimuli (e.g., Henson, 1998a . Item repetition in short-term memory: Ranschburg repeated. Journal of Experimental Psychology: Learning, Memory, and Cognition, 24(5), 1162-1181. doi:doi.org/10.1037/0278-7393.24.5.1162). These data are the first to demonstrate the Ranschburg effect with non-verbal stimuli and suggest further cross-modal similarities in order memory.

  18. Effects of piracetam on behavior and memory in adult zebrafish.

    Science.gov (United States)

    Grossman, Leah; Stewart, Adam; Gaikwad, Siddharth; Utterback, Eli; Wu, Nadine; Dileo, John; Frank, Kevin; Hart, Peter; Howard, Harry; Kalueff, Allan V

    2011-04-25

    Piracetam, a derivative of γ-aminobutyric acid, exerts memory-enhancing and mild anxiolytic effects in human and rodent studies. To examine the drug's behavioral profile further, we assessed its effects on behavioral and endocrine (cortisol) responses of adult zebrafish (Danio rerio)--a novel model species rapidly gaining popularity in neurobehavioral research. Overall, acute piracetam did not affect zebrafish novel tank and light-dark box behavior at mild doses (25-400mg/L), but produced nonspecific behavioral inhibition at 700mg/L. No effects on cortisol levels or inter-/intra-session habituation in the novel tank test were observed for acute or chronic mild non-sedative dose of 200mg/L. In contrast, fish exposed to chronic piracetam at this dose performed significantly better in the cued learning plus-maze test. This observation parallels clinical and rodent literature on the behavioral profile of piracetam, supporting the utility of zebrafish paradigms for testing nootropic agents. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Shape memory effect and superelasticity of titanium nickelide alloys implanted with high ion doses

    International Nuclear Information System (INIS)

    Pogrebnjak, A D; Bratushka, S N; Beresnev, V M; Levintant-Zayonts, N

    2013-01-01

    The state of the art in ion implantation of superelastic NiTi shape memory alloys is analyzed. Various technological applications of the shape memory effect are outlined. The principles and techiques of ion implantation are described. Specific features of its application for modification of surface layers in surface engineering are considered. Key properties of shape memory alloys and problems in utilization of ion implantation to improve the surface properties of shape memory alloys, such as corrosion resistance, friction coefficient, wear resistance, etc. are discussed. The bibliography includes 162 references

  20. Effects of selective phosphodiesterases-4 inhibitors on learning and memory: a review of recent research.

    Science.gov (United States)

    Peng, Sheng; Sun, Haiyan; Zhang, Xiaoqing; Liu, Gongjian; Wang, Guanglei

    2014-09-01

    Phosphodiesterase-4 (PDE-4) regulates the intracellular level of cyclic adenosine monophosphate. Recent studies demonstrated that PDE-4 inhibitors can counteract deficits in long-term memory caused by aging or increased expression of mutant forms of human amyloid precursor proteins, and can influence the process of memory function and cognitive enhancement. Therapeutics, such as ketamine, a drug used in clinical anesthesia, can also cause memory deficits as adverse effects. Targeting PDE-4 with selective inhibitors may offer a novel therapeutic strategy to prevent, slow the progress, and, eventually, treat memory deficits.