Search Results
Results 351 - 400 of 1393
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Finn P R - - 2001
This study investigated whether low levels of the personality trait of constraint and early-onset alcoholism would be associated with deficits in aversive conditioning and smaller responses to novelty in a stimulus mismatch protocol. Personality traits (constraint and socialization) and skin conductance responses (SCRs) during conditioning and novelty paradigms were assessed ...
McDevitt M A - - 2001
Pigeons chose between 5-s and 15-s delay-of-reinforcement alternatives. The first key peck to satisfy the choice schedule began a delay timer, and food was delivered at the end of the interval. Key pecks during the delay interval were measured, but had no scheduled effect. In Experiment 1, signal conditions and ...
Jones R B - - 2001
1. Previous studies have shown that a bunch of string is a particularly attractive pecking stimulus for chicks and adult laying hens. Because movement is thought to be an important attribute of enrichment objects, this study determined whether occasional movement would affect the attractiveness of this device. 2. In experiment ...
Kelly R - - 2001
The differential outcomes effect (DOE) pertains to enhanced conditional discrimination performance if each correct stimulus-choice sequence is always followed by a different outcome (e.g., food vs. water) compared to when each correct sequence is followed equally often by either outcome. The present experiments sought evidence of a DOE in pigeons, ...
Lattal K A - - 2001
Correspondence between saying and doing, typically studied in young children and individuals with developmental disabilities, was examined as an instance of conditional stimulus control. In Experiment 1, 3 pigeons were exposed to a two-component repeated-trials procedure. In the first-sample or say-component, two response keys transilluminated by different colored lights were ...
Hagopian L P - - 2001
Most preference assessments require individuals to choose among two or more stimuli. More recently, the duration of engagement with items has been used as an index of preference. In the current study, the predictive validity of a single stimulus engagement (SSE) preference assessment was evaluated with 4 individuals. Stimuli were ...
Carr J E - - 2001
The effects of fixed-time (FT) and variable-time (VT) schedules on responding were evaluated with 2 adults with mental retardation. Multielement and reversal designs were used to compare the effects of FT and VT schedules in reducing responses previously maintained on variable-ratio reinforcement schedules. The schedules were equally effective in reducing ...
Bickel W K - - 2000
BACKGROUND: Relative reinforcing efficacy has been assumed to be a homogeneous phenomenon referring to the behavior-strengthening or behavior-maintaining effects of a drug reinforcer. However, a variety of studies suggest that relative reinforcing efficacy may be heterogeneous. OBJECTIVES: The purpose of this theoretical proposal is to examine the difficulties associated with ...
Cardinal R N RN Department of Experimental Psychology, University of Cambridge, - - 2000
Inability to tolerate delays to reward is an important component of impulsive behaviour, and has been suggested to reflect dysfunction of dopamine systems. The present experiments examined the effects of signalling a delayed, large reward on rats' ability to choose it over a small, immediate reward, and on the response ...
Jones RB - - 2000
Environmental enrichment is thought likely to benefit chickens and farmers in many ways; these include reduced fearfulness and feather pecking and improved productivity. Enrichment devices would intuitively be more effective if they reliably attracted and sustained appreciable interest but many fail to do so. This may reflect the fact that ...
Romaniuk C B - - 2000
Five conditioned suppression experiments examined the extent to which an appetitively motivated lever-press response can be punished by different components of a backward conditioned stimulus (CS). Using a 0-s unconditioned stimulus (US)-CS interval, Experiments 1 and 2 showed that the initial 3 s of a normally 30-s backward CS served ...
Lovibond P F - - 2000
Two experiments examined the ability of an added stimulus to interfere with extinction of a target excitatory fear stimulus (a predictor of shock) in human autonomic conditioning. Both experiments demonstrated disruption of extinction when the added stimulus was inhibitory (a predictor of no shock, or safety signal). Subjects showed a ...
Odum A L - - 2000
Changes produced by drugs in response patterns under fixed-interval schedules of reinforcement have been interpreted to result from changes in temporal discrimination. To examine this possibility, this experiment determined the effects of morphine on the response patterning of 4 pigeons during a fixed-interval 1-min schedule of food delivery with interpolated ...
Park J H - - 2000
In 2 experiments, the authors manipulated the frequency of concurrent feedback to discern the effects on learning. In each experiment, participants (N = 48, Experiment 1; N = 36, Experiment 2) attempted to reproduce a criterion force-production waveform (5 s in duration) presented on the computer monitor. Consistent with the ...
Kehoe EJ - - 2000
Five experiments were conducted in which the onset of a tone conditioned stimulus (CS) preceded the unconditioned stimulus (US) by 500 ms. Across experiments, the offset of the CS was extended past the offset of the US by values ranging from 0 ms to 40000 ms. Extensions of the CS ...
Harper DN - - 2000
We attempted to demonstrate that timing performance on a temporal discrimination would be enhanced if rats were required to fill a duration with behavior than when they were not required to respond. Six rats were trained to discriminate between a 3- and 9-s stimulus in a symbolic-matching-to-sample task. In two ...
Bennett C H - - 2000
In three experiments, rats were pre-exposed either to uncorrelated presentations of a light and sucrose pellets (group CS/US) or to equivalent presentations of the light and pellets in separate sessions (control). In Experiment 1, subsequent conditioning to the light proceeded more slowly in group CS/US than in the control group, ...
Medina J F - - 2000
We used large-scale computer simulations of eyelid conditioning to investigate how the cerebellum generates and makes use of temporal information. In the simulations the adaptive timing displayed by conditioned responses is mediated by two factors: (1) different sets of granule cells are active at different times during the conditioned stimulus ...
Sidman M - - 2000
Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2-, 3-, 4-, 5-, or n-term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional ...
Rescorla R A - - 2000
Five experiments used rat subjects to investigate the impact on extinction of the presence of other conditioned stimuli. In Experiments 1 (Pavlovian magazine approach) and 2 (instrumental discriminative training), an excitatory stimulus (X) was extinguished alone, in conjunction with a previously reinforced other stimulus (A), in conjunction with previously nonreinforced ...
Arrindell W A - - 2000
Research designed to determine the number and kind of dimensions underlying self-reports of animal fears is relatively rare. To contribute further knowledge to this area of study, Davey's methodology [Davey, G. C. L. (1994a). Self-reported fears to common indigenous animals in an adult UK population: the role of disgust sensitivity. ...
Gunther L M - - 2000
Presentation of unsignalled unconditioned stimuli (USs) interspersed among Pavlovian excitatory conditioning trials weakens conditioned responding to a target conditioned stimulus (CS; Rescorla, 1968). However, signalling these intertrial USs with another cue (a cover stimulus) has been shown to alleviate this degraded-contingency effect (e.g. Durlach, 1982, 1983). In contrast to signalling ...
O'Donnell J - - 2000
Two experiments demonstrated stimulus control and generalization of conditioned punishment with humans. In both studies, responses first were reinforced with points exchangeable for money on a variable-interval schedule in the presence of one line length (S(D)). Next, a second line length was introduced, and point loss followed every response in ...
Müller D - - 2000
Sensory preconditioning means that reinforcement of stimulus A after unreinforced exposure to a compound AB also leads to responses to stimulus B. Here, we describe and analyze sensory preconditioning in an insect, the honeybee Apis mellifera. Using two-element odorant compounds in classical conditioning of the proboscis extension reflex, we found ...
Belke T W - - 2000
Previous investigations of wheel-running reinforcement that manipulated reinforcer duration across conditions showed a strong relation between wheel-running rate and average postreinforcement pause (PRP) duration. To determine if the basis of this relation across conditions was a local effect of fatigue or satiation, the correlation between revolutions run and the duration ...
Schaal D W - - 2000
In two experiments the conditioned reinforcing and delayed discriminative stimulus functions of stimuli that signal delays to reinforcement were studied. Pigeons' pecks to a center key produced delayed-matching-to-sample trials according to a variable-interval 60-s (or 30-s in 1 pigeon) schedule (Experiment 1) or a multiple variable-interval 20-s variable-interval 120-s schedule ...
Clement T S TS University of Kentucky, Lexington, - - 2000
Stimuli associated with less effort or with shorter delays to reinforcement are generally preferred over those associated with greater effort or longer delays to reinforcement. However, the opposite appears to be true of stimuli that follow greater effort or longer delays. In training, a simple simultaneous discrimination followed a single ...
McNish K A - - 2000
The role of the dorsal hippocampus in contextual fear conditioning was investigated with a contextual blocking paradigm. In Experiment 1, rats were given pairings of a light conditioned stimulus (CS) and footshock after preexposure either to footshock or to the context alone. The group preexposed to footshock showed poorer fear ...
Panlilio L V - - 2000
When 2 stimuli that occasion cocaine self-administration are presented in compound, their ability to increase cocaine-reinforced operant responding is substantially enhanced. The goal of the present experiment was to determine whether stimulus compounding could produce analogous enhancements of a classically conditioned drug effect. Food-maintained responding in rats was suppressed by ...
Reed Phil - - 2000
The present article outlines the potential benefits to the treatment of stuttering, if altered auditory feedback methods, especially frequency-shifted feedback, were to be combined with behaviour modification techniques. A potential framework for understanding the integration of these approaches is presented in the context of assessing the limitations of each approach ...
Funk D - - 2000
A central question in olfactory learning is how animals become tuned to odor stimuli that gain significance through conditioning. A leading view is that tuning to conditioned odor stimuli involves functional modifications within the primary olfactory pathways, themselves.(7) Here we studied this idea further by investigating responses within the olfactory ...
Gruart A - - 2000
The classical conditioning of the eyelid motor system in alert behaving rabbits has been used to study the expression of Fos in the hippocampus, and in the occipital, parietal, piriform and temporal cortices. Animals were classically conditioned with both delay and trace conditioning paradigms. As conditioned stimulus, both short and ...
Purdy J E - - 1999
Two groups of cuttlefish (Sepia officinalis) were used to demonstrate classical conditioning in this species and to determine whether the resulting approach response would be that of sign tracking or goal tracking. For cuttlefish in the paired condition, a flashing light was presented at one end of a long tank ...
Dzendolet E - - 1999
The Theory of Behavioral Mechanics is the behavioral analogue of Newton's laws of motion, with the rate of responding in operant conditioning corresponding to physical velocity. In an earlier work, the basic relation between rate of responding and sessions under two FI schedules and over a range of commonly used ...
Urcuioli P J - - 1999
Three experiments assessed the impact of sample duration on pigeons' delayed matching as a function of whether or not the samples themselves signaled how long they would remain on. When duration was uncorrelated with the sample appearing on each matching trial, the typical effect of duration was observed: Choice accuracy ...
See R E - - 1999
Previous studies have demonstrated that conditioned stimuli can increase responding on a drug-associated lever after extinction from drug self-administration. The present study investigated singular stimuli (tone or light) or a compound stimulus (tone + light) for their ability to increase extinguished responding following chronic cocaine self-administration. Rats self-administered cocaine for ...
Guenther F H - - 1999
Psychophysical phenomena such as categorical perception and the perceptual magnet effect indicate that our auditory perceptual spaces are warped for some stimuli. This paper investigates the effects of two different kinds of training on auditory perceptual space. It is first shown that categorization training using nonspeech stimuli, in which subjects ...
Talk A C - - 1999
The neurophysiological basis for context conditioning is conceptually problematic because neurophysiological descriptions of activity-dependent (associative) forms of neuronal plasticity uniformly assume that a specific temporal relationship between signals is necessary for memory induction. In the present experiments, this problem is addressed empirically by presenting, as a temporally diffuse contextual signal, ...
Aguilar C M - - 1999
Tversky's (1977) seminal work on directionality injudgments of similarity demonstrated that people may not judge the similarity of A to B to be equal to the similarity of B to A. In a series of studies, we investigated comparison asymmetries. In Experiment 1, our aim was to extend Tversky's findings ...
Hunt P S - - 1999
This series of experiments was designed to reexamine the ontogenetic emergence of the fear-potentiated startle response in rats. Previous results (Hunt, Richardson, & Campbell, 1994) indicated that potentiated startle to a light conditioned stimulus (CS) paired with an acoustic unconditioned stimulus (US) was not observed until 30 days of age. ...
Rescorla R A - - 1999
Four experiments investigated the symmetry of associative changes in stimulus compounds and elements in a Pavlovian conditioned magazine-approach situation with rats. Experiment 1 used multiple groups to examine the associative changes in a conditioned element (A) as a result of its subsequent reinforcement in compound with a neutral X. These ...
Saunders R R - - 1999
Preschool children were taught four two-choice match-to-sample conditional discriminations with 10 arbitrary visual stimuli. For 6 participants, 2 of the 10 stimuli served as the sample, or conditional, stimuli in all discriminations. For 5 additional participants, the same pair of stimuli served as the discriminative, or comparison, stimuli in all ...
Talwar S K - - 1999
The frequency-discrimination behavior of rats in a simple go/no-go task was analyzed using the theory of signal detection. Discrimination acuity was studied and the receiver operating characteristic (ROC) was generated in subjects by varying the reinforcement schedule and signal probability. The detectability indices d', A', and sensitivity index (SI) and ...
Kisch J - - 1999
An operant learning protocol was developed for honeybees that are fixed in small tubes. The bees had to touch one or two small silver plates within the range of one antenna. The contacts of the antenna with the silver plates were registered electronically. Three conditioning protocols were analysed. In the ...
Lazev A B - - 1999
Smoking-related cues tend to produce urges and cardiac responses in smokers. This reactivity has been assumed to reflect prior classical conditioning. However, little direct evidence exists supporting the notion that environmental cues can be classically conditioned to cigarette smoking. In this study, 8 smokers received 22 daily trials during which ...
Roscoe E M - - 1999
We compared results obtained in two previous studies on reinforcer identification (Fisher et al., 1992; Pace, Ivancic, Edwards, Iwata, & Page, 1985) by combining methodologies from both studies. Eight individuals with mental retardation participated. During Phase 1, two preference assessments were conducted, one in which stimuli were presented singly (SS ...
Slawecki C J - - 1999
It has been hypothesized that environmental stimuli previously paired with ethanol consumption play a role in excessive ethanol intake. This study examined the ability of orally self-administered ethanol to establish a tone-light stimulus complex as a conditioned reinforcer (CSR). Male Long-Evans rats were trained to orally self-administer 10% ethanol (10E) ...
Higbee T S - - 1999
Recent research in the area of stimulus-preference assessment has progressively improved the accuracy and efficiency of this technology for predicting reinforcer potency. One way to potentially improve the efficiency of the procedure might be to use pictorial representations of stimuli in the assessment rather than the stimuli themselves. To determine ...
Nsegbe E - - 1998
The authors performed a differential conditioning experiment in 30 rats, using 2 odors as the conditioned stimuli (CS+ and CS-) and hypoxia (8% O2) as the unconditioned stimulus. Vanillin was the CS+ and rose the CS- in half of the rats, and vice versa in the other half. Fifteen paired ...
Walker D J - - 1998
In Experiment 1 pigeons pecked a key that was illuminated with a 501-nm light and obtained food by doing so according to a variable-interval (VI) schedule of reinforcement, the mean value of which differed across groups: either 30 s, 120 s, or 240 s. The pigeons in all three groups ...
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