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Rosenblatt Gilad - - 2010
A circular zero-time-averaged power component, coupling the forward (dielectric) and backward (metal) power channels of Surface Plasmon Polaritons (SPPs), is shown to be the core ingredient for the slow-light characteristic of SPPs at the surface plasmon frequency, for both a lossless and lossy metal. Additional slow-light regimes emerging in configurations ...
Adhikari Ravi M - - 2010
Co-precipitation of 1,4-bis(2-phenyl-1-propen-1-yl)benzene (1) and 2-(4-(2-(4-(3,6-di-tert-butyl-9H-carbazol-9-yl)phenyl)ethynyl)benzylidene) malononitrile (2) that individually form blue-emitting and orange-emitting nanoparticles, respectively, results in the formation of composite fluorescent organic nanoparticles that emit white light. The two components likely align in the head-to-tail fashion in nanoparticles, creating two parallel and strongly coupled transition dipoles. The emission ...
Primo Ana - - 2011
This Perspective is focused on the photocatalytic activity of gold nanoparticles supported on titania (Au/TiO(2)). Titania is the most widely used photocatalyst, but its limited activity under visible light irradiation has motivated the quest for modified titania materials absorbing visible light. The review starts by justifying how doping with metallic ...
Dack Charlotte - - 2010
The aim of the four present experiments was to explore how different schedules of reinforcement influence schedule-induced behavior, their impact on evaluative ratings given to conditioned stimuli associated with each schedule through evaluative conditioning, and the transfer of these evaluations through derived stimulus networks. Experiment 1 compared two contrasting response ...
Zhu Jianjun - - 2010
The Eu(3+) doped TiO2-SiO2 photocatalysts, as a reclaimed visible-light responsive photocatalyst, were prepared by sol-gel method with TEOS, TBT and europium nitrate as precursors, by keeping the molar of TEOS:TBT constant at 1:1 and with different europium doping content. The resulting photocatalysts were characterized by XRD, TEM, SEM, EDX, UV-VIS ...
Tanno Takayuki - - 2010
In the first condition in Experiment 1, 6 rats were exposed to concurrent variable ratio (VR) 30, variable interval (VI) 30-sec schedules. In the next two conditions, the subjects were exposed to concurrent VI VI schedules and concurrent tandem VI-differential-reinforcement-of-high-rate VI schedules. For the latter conditions, the overall and relative ...
Del Giudice Marco - - 2010
It is commonly assumed that, whereas auditory and olfactory learning take place already during fetal development, visual experience and learning are not possible before birth. This paper explores the conditions for visual experience in the last two months of human gestation, when the fetal visual system is mature enough to ...
Burns Rosalind - - 2011
A new Pavlovian conditioning preparation was developed using the nictitating membrane of the restrained pigeon. Either visual or auditory stimuli served as conditioned stimuli (CSs) with an unconditioned stimulus (US) of a puff of air to the cornea. Movement of the nictitating membrane constituted the conditioned and unconditioned responses (CR ...
Kreider Joy C JC Center for Learning and Memory, Section of Neurobiology, University of Texas at Austin, Austin, Texas 78712, - - 2010
Conceptual and practical advantages of pavlovian eyelid conditioning facilitate analysis of cerebellar computation and learning. Even so, eyelid conditioning procedures are unrealistic in an important way. The error signal to the olivocerebellar system does not decrease as learning adapts response amplitude or gain. This inherently limits the utility of eyelid ...
Popov Alexey P - - 2010
In this review, we discuss the use of inorganic nanoparticles, mainly zinc oxide (ZnO) and titanium dioxide (TiO2), for sunscreen applications considering their intrinsic physical properties and the Mie theory. These properties cause, from one side, attenuation of the ultraviolet light by absorption and scattering (dependent on a particle size), ...
Schultz Douglas H DH Department of Psychology, University of Wisconsin–Milwaukee, PO Box 413, Milwaukee, WI 53211, - - 2010
The role of contingency awareness in classical conditioning experiments using human subjects is currently under debate. This study took a novel approach to manipulating contingency awareness in a differential Pavlovian conditioning paradigm. Complex sine wave gratings were used as visual conditional stimuli (CS). By manipulating the fundamental spatial frequency of ...
Missig Galen - - 2010
Oxytocin reportedly decreases anxious feelings in humans and may therefore have therapeutic value for anxiety disorders, such as post-traumatic stress disorder (PTSD). As PTSD patients have exaggerated startle responses, a fear-potentiated startle paradigm in rats may have face validity as an animal model to examine the efficacy of oxytocin in ...
Doughty Adam H - - 2011
Resurgence typically refers to the recovery of a previously reinforced response when a more recently reinforced response is extinguished. Under conditions of punishment, Wilson and Hayes (1996) observed the recovery of derived stimulus relations that never had been correlated with differential consequences. The present study systematically replicated the findings of ...
Zelikowsky Moriel M Department of Psychology and Brain Research Institute, University of California, Los Angeles, - - 2010
In Pavlovian overshadowing, a stimulus that predicts a biologically important event reduces conditioning to another, equally predictive stimulus. We tested the effects of an opioid antagonist and dopamine agonist on the ability of a salient white noise to overshadow a less salient light. Rats were conditioned to fear a light ...
Yoon Taejib T Department of Psychology, University of Washington, Seattle, WA 98195-1525, United - - 2011
Three experiments examined the role of the dorsal hippocampus (dHIPP) in occasion setting with diffuse contextual and discrete light stimuli serving as occasion setters in classical fear conditioning with rats. Both sham-operated and dHIPP-lesioned animals readily learned a L→T+, T- serial feature-positive discrimination in which a light (L) "set the ...
Grondin Simon - - 2010
How constant is the Weber fraction (WF) for brief time intervals? This question was assessed in three experiments with two base durations (BDs), 0.2 and 1 sec, and with different ways of estimating the WF. In Experiment 1, the psychometric functions were drawn on the basis of 4, 8, or ...
Holtzman Orit - - 2010
We studied the learning produced by simple exposures to a stimulus. Exposures depressed orienting and subsequent conditioned freezing in rats. A remotely preexposed conditioned stimulus (CS) conditioned better and overshadowed a novel CS more than a recently preexposed CS. Additional preexposures reversed these effects: a remotely preexposed CS elicited more ...
Neuringer Allen - - 2010
A behavior-based theory identified 2 characteristics of voluntary acts. The first, extensively explored in operant-conditioning experiments, is that voluntary responses produce the reinforcers that control them. This bidirectional relationship-in which reinforcer depends on response and response on reinforcer-demonstrates the functional nature of the voluntary act. The present article focuses on ...
Barker David J - - 2010
Bright light was an effective aversive stimulus for Wistar rats in punishment, escape, and avoidance paradigms. Contingent punishment of lever pressing maintained by concurrent schedules of food delivery shifted presses to an alternate lever, and depressed overall response rates. Periodic non-contingent presentation of the light prompted escape responding (head entry ...
Alessandri Jérôme - - 2010
Past studies using the concurrent-chain procedure showed that pigeons and humans generally prefer an unsegmented schedule to a segmented schedule. This finding is ostensibly inconsistent with theories of conditioned reinforcement such as delay-reduction theory. In the present study with humans, two changes in the basic segmented schedule were implemented to ...
Silberberg Alan A American University, United States. - - 2010
Observing responses are those that produce stimuli correlated with the availability (S+) or non-availability (S-) of reinforcement but that has no influence on the actual delivery or timing of reinforcement. Prior research has shown that observing is maintained by the occasional production of the S+ ("good news") and not by ...
Stagner Jessica P - - 2010
Contrary to the law of effect and optimal foraging theory, pigeons show suboptimal choice behavior by choosing an alternative that provides 20% reinforcement over another that provides 50% reinforcement. They choose the 20% reinforcement alternative--in which 20% of the time, that choice results in a stimulus that always predicts reinforcement, ...
Williams Douglas A - - 2010
One way to minimize excitation acquired by the conditioned stimulus (CS) is to introduce intertrial presentations of the unconditioned stimulus (US). However, even in the presence of frequent intertrial USs, Experiments 1a and 1b found that rats anticipated the customary arrival time of a food pellet US when it occurred ...
Sanchez Hayde H Department of Psychiatry, Division of Molecular Psychiatry, Yale University School of Medicine, New Haven, Connecticut 06508, - - 2010
Drug addiction is a chronic disorder associated with recurrent craving and relapse often precipitated by the presence of drug-associated stimuli. Pharmacological and behavioral treatments that disrupt drug-associated stimulus memories could be beneficial in the treatment of addictive disorders. Memory restabilization (or reconsolidation) following retrieval of drug-paired stimuli depends upon the ...
Garcia Kristen A - - 2010
Auditory streaming is a phenomenon that has been documented in a wide variety of animal species. Recently, space, intensity, time, and spectral composition were all found to be important factors for auditory streaming of birdsong by budgerigars and zebra finches, although the cues varied in importance. Those experiments were extended ...
McDevitt Margaret A - - 2010
Pigeons were presented with a concurrent-chains schedule in which the total time to primary reinforcement was equated for the two alternatives (VI 30 s VI 60 s vs. VI 60 s VI 30 s). In one set of conditions, the terminal links were signaled by the same stimulus, and in another set of conditions ...
Lie Celia - - 2010
The present experiment examined the effects of varying stimulus disparity and relative punisher frequencies on signal detection by humans. Participants were placed into one of two groups. Group 3 participants were presented with 1:3 and 3:1 punisher frequency ratios, while Group 11 participants were presented with 1:11 and 11:1 punisher ...
Fantino Edmund E Department of Psychology-0109, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0109, USA. - - 2010
Results from studies of observing responses have suggested that stimuli maintain observing owing to their special relationship to primary reinforcement (the conditioned-reinforcement hypothesis), and not because they predict the availability and nonavailability of reinforcement (the information hypothesis). The present article first reviews a study that challenges that conclusion and then ...
McMillan Neil N Department of Psychology, University of Western Ontario, London, Ontario N6A 5C2, Canada. - - 2010
We studied the effects of cue competition on timing in both overshadowing and blocking operant procedures with pigeons. A white center key delivered reward when pecked 30s after a red or green sidekey was presented and 10s after presentation of the alternate color on the other sidekey. In Experiment 1, ...
Podlesnik Christopher A CA Department of Pharmacology, University of Michigan Medical School, 3415 Medical Science Building I, 1301 Catherine Street, Ann Arbor, MI 48109-5632, United States. - - 2010
Previous experiments on behavioral momentum have shown that relative resistance to extinction of operant behavior in the presence of a discriminative stimulus depends upon the baseline rate or magnitude of reinforcement associated with that stimulus (i.e., the Pavlovian stimulus-reinforcer relation). Recently, we have shown that relapse of operant behavior in ...
Hampson C L - - 2010
Rats' ability to discriminate durations is disrupted by the monoamine-releasing agent D-amphetamine and the 5-HT2 receptor agonist 2,5-dimethoxy-4-iodoamphetamine (DOI). It is unknown whether this effect is specific for temporal discrimination or reflects general disruption of stimulus control. This experiment addressed this question by comparing the effects of D-amphetamine and DOI ...
Santi Angelo - - 2010
Pigeons were trained in a within-subjects design to discriminate empty intervals (bound by two 1-sec visual markers) and filled intervals (a continuous visual signal). The intervals were signaled by different visual stimuli and they required responses to different sets of comparison stimuli. In Experiment 1, empty intervals were judged longer ...
Halverson Hunter E - - 2010
The conditioned stimulus (CS) pathway that is necessary for visual delay eyeblink conditioning was investigated in the current study. Rats were initially given eyeblink conditioning with stimulation of the ventral nucleus of the lateral geniculate (LGNv) as the CS followed by conditioning with light and tone CSs in separate training ...
Zion Boaz B Institute of Agricultural Engineering, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. - - 2010
Groups of common carp (Cyprinus carpio) were trained for 33 days to discriminate between two acoustic signals differing in frequency and temporal pattern. One signal (positive stimulus) was reinforced by food, while the other (negative stimulus) was not rewarded. When exposed to 3 positive and 3 negative stimuli per day ...
Freestone David M DM Brown University, United States. David - - 2010
Shifts in the psychometric function in the Free Operant Psychophysical Procedure (FOPP) have traditionally been explained by suggesting the pacemaker rate is proportional to the reinforcement rate (Behavioral Theory of Timing; BeT), or by direct associative competition between the two responses (Learning to Time; LeT). The application of these models ...
Yoshida Masayuki - - 2010
BACKGROUND: Besides the amygdala, of which emotion roles have been intensively studied, the cerebellum has also been demonstrated to play a critical role in simple classical fear conditioning in both mammals and fishes. In the present study, we examined the effect of local administration of the anesthetic agent lidocaine into ...
Gutierrez-Martinez Olga - - 2010
The present study investigated the use of a VR stereoscopic figure as conditioned stimulus (CS). A differential conditioning procedure was applied on 67 participants, where a VR stereoscopic figure (CS+) was paired with electric shock and other VR stereoscopic figure (CS-) was presented without shock. Evaluative and expectancy measures were ...
Pietras Cynthia J - - 2010
An experiment with adult humans investigated the effects of response-contingent money loss (response-cost punishment) on monetary-reinforced responding. A yoked-control procedure was used to separate the effects on responding of the response-cost contingency from the effects of reduced reinforcement density. Eight adults pressed buttons for money on a three-component multiple reinforcement ...
Stahlman W David WD Department of Psychology, University of California Los Angeles, Los Angeles, CA 90095-1563, - - 2010
Gharib, Derby, and Roberts (2001) proposed that reducing reward expectation increases variation of response form. We tested this rule in a new situation and asked if it also applied to variation of response location and timing. In 2 discrete-trial experiments, pigeons pecked colored circles for food. The circles were of ...
Langton Julia M - - 2010
Recent findings show that the switch from NMDAr-dependent extinction to NMDAr-independent re-extinction is both context and stimulus specific. In this study we examined whether this switch was temporally specific as well. Re-extinction was found to be NMDAr-independent when it occurred 2 days after initial extinction but NMDAr-dependent when it occurred ...
Nanbu Makoto - - 2010
The processes of fear conditioning and extinction are thought to be related to the pathophysiology of anxiety disorders including obsessive-compulsive disorder (OCD). We have reported alterations of auditory P50 suppression in human fear conditioning and extinction in healthy control subjects (Kurayama et al., 2009). In the study, P50 suppression was ...
Svensson P?r - - 2010
Pavlovian eyeblink conditioning is a useful experimental model for studying adaptive timing, an important aspect of skilled movements. The conditioned response (CR) is precisely timed to occur just before the onset of the expected unconditioned stimulus (US). The timing can be changed immediately, however, by varying parameters of the conditioned ...
Gipson Cassandra D - - 2009
When pigeons are given a choice between an initial-link alternative that results in either a terminal-link stimulus correlated with 100% reinforcement or a stimulus correlated with 0% reinforcement (overall 50% reinforcement) and another initial-link alternative that always results in a terminal-link stimulus correlated with 100% reinforcement, some pigeons show a ...
Urcelay Gonzalo P - - 2009
Three Pavlovian fear conditioning experiments with rats as subjects explored the effect of extinction in the presence of a concurrent excitor. Our aim was to explore this particular treatment, documented in previous studies to deepen extinction, with novel control groups to shed light on the processes involved in extinction. Relative ...
Podlesnik Christopher A CA Utah State University, Logan, Utah 84322, - - 2009
Previous experiments on behavioral momentum have shown that relative resistance to extinction of operant behavior in the presence of a stimulus depends on the rate of reinforcement associated with that stimulus, even if some of those reinforcers occur independently of the behavior. We present three experiments examining whether the rate ...
Kehoe E James - - 2009
The present experiment characterized conditioned nictitating membrane (NM) movements as a function of CS duration, using the full range of discernible movements (>.06 mm) rather than movements exceeding a conventional criterion (>.50 mm). The CS-US interval was fixed at 500 ms, while across groups, the duration of the CS was ...
Sorge Robert E - - 2009
RATIONALE AND OBJECTIVE: Intravenous infusions of nicotine appear to exert little primary reinforcing effects in adult rats but, instead, maintain self-administration behavior at least, in part, by increasing the intrinsic reinforcing effects of drug-paired sensory stimuli. The present study examined instead the impact of a motivationally neutral cue on self-administration. ...
Escobar Rogelio - - 2009
The control exerted by a stimulus associated with an extinction component (S-) on observing responses was determined as a function of its temporal relation with the onset of the reinforcement component. Lever pressing by rats was reinforced on a mixed random-interval extinction schedule. Each press on a second lever produced ...
Podlesnik Christopher A - - 2009
Stimuli uncorrelated with reinforcement have been shown to enhance response rates and resistance to disruption; however, the effects of different rates of stimulus presentations have not been assessed. In two experiments, we assessed the effects of adding different rates of response-dependent brief stimuli uncorrelated with primary reinforcement on relative response ...
Antunes Raquel A - - 2009
In many territorial species androgens respond to social interactions. This response has been interpreted as a mechanism for adjusting aggressive motivation to a changing social environment. Therefore, it would be adaptive to anticipate social challenges and reacting to their clues with an anticipatory androgen response to adjust agonistic motivation to ...
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