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Results 601 - 650 of 1347
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Forzano L B - - 1995
Experiment 1 used 6 preschool boys and Experiment 2 used 6 adult women to explore the effects of food preference on humans' choice in self-control paradigms. The boys showed a higher proportion of responses for more delayed, larger reinforcers (a measure of self-control) when those choices resulted in receipt of ...
Green L - - 1995
In three experiments pigeons played (i.e., chose between two colored keys) iterated prisoner's dilemma and other 2 x 2 games (2 participants and 2 options) against response strategies programmed on a computer. Under the prisoner's dilemma pay-off matrix, the birds generally defected (i.e., pecked the color associated with not cooperating) ...
Schaal D W - - 1995
Four pigeons deprived to 80% of their laboratory free-feeding weights pecked keys under a multiple fixed-ratio 30 fixed-interval 5-min schedule of food presentation. Components alternated strictly with 15-s timeouts separating them; each was presented six times. When rates of pecking were stable, 2 pigeons' weights were reduced to 70%, and ...
Bell S.M. - - 1995
The aim of this study was to develop a procedure to establish orally delivered cocaine as a reinforcer for rats. Several procedures that have proven reliable in other studies were instituted. (1) Food-induced drinking: food was presented to engender high rates of drinking, then cocaine solutions replaced water, and finally ...
Bauman R A - - 1995
A principal purpose of the present study was to characterize rats' demand for food by increasing the required delay between the alternation of leverpresses. While living in cages that were exposed to a 12:12 light:dark cycle, rats were required to alternate leverpresses for their entire daily food ration. After a ...
Repp B H - - 1995
This study investigated the perception and production of legato ("connected") articulation in repeatedly ascending and descending tone sequences on a digital piano (Roland RD-250s). Initial measurements of the synthetic tones revealed substantial decay times following key release. High tones decayed faster than low tones, as they did prior to key ...
Roehr J - - 1995
Schedule-induced polydipsia was induced when food-deprived rats were subjected to a fixed-time (60 s) feeding schedule for 150 min daily for 3 weeks (training period). Subsequent chronic administration of the serotonin reuptake inhibitor fluoxetine reduces schedule-induced polydipsia over 2-4 weeks. We asked whether changes in the serotonin reuptake carrier occur ...
Bateson M - - 1995
Much research has focused on the effects of environmental variability on foraging decisions. However, the general pattern of preference for variability in delay to reward and aversion to variability in amount of reward remains unexplained a either a mechanistic or a functional level. Starlings' preferences between a fixed and a ...
Alling K - - 1995
Rats were exposed to two-component multiple schedules of food delivery. In the first experiment, 15 responses were required to produce food in both components. A downward force of 0.25 N (25 g) was always required to operate the response lever in one component. In the other, the required force was ...
Nader M A - - 1995
The purpose of the present study was to examine whether a history of responding under food reinforcement schedules that generated either high or low response rates would influence the acquisition and maintenance of cocaine self-administration. Eight experimentally naive rhesus monkeys were initially trained to respond on the right lever under ...
Deich J D - - 1995
Food pecking in the ring dove is a skilled prehensile response that is similar to, but simpler than, many other prehensile responses. Previous work has shown that this response is initially poorly executed and requires experience for its accurate direction and coordination. The response involves two components: the thrusting of ...
Pearce J M - - 1995
In Experiment 1, rats received an A+AX degrees discrimination in which food was presented after Stimulus A by itself but not after a simultaneous compound of A with Stimulus X. AX was then paired with food in a 2nd stage, followed by test trials with A alone. Responding on the ...
Perkins K A - - 1995
Smoking may enhance satiety following meal consumption, thereby reducing subsequent eating (i.e., between-meal snacks), especially in women high in dietary restraint. Female smokers (n = 20, 10 high and 10 low restraint) and male smokers (n = 10) participated in two sessions, involving overnight abstinence from food and smoking (smoking ...
Jones C A - - 1995
Although the progressive-ratio schedule has been used frequently to quantify the reinforcing effectiveness of self-administered drugs, it has seldom been used to examine the effects of drugs on food-maintained behavior and has never been used to evaluate the effects of cocaine on such behavior. In the present study, the effects ...
Fletcher P J - - 1995
Previous studies have shown that long-term 5-hydroxytryptamine (5-HT) depletion induced by combined dorsal and median raphe injections of 5,7-dihydroxytryptamine (5,7-DHT) leads to impairments in the acquisition and performance of behaviour maintained under a differential-reinforcement-of-low-rate (DRL) schedule of reinforcement. The present studies examined the relative importance of dorsal versus median raphe ...
Mazur J E - - 1995
In an adjusting-delay choice procedure, pigeons could peck on either a red key or a green key. A peck on the red key always led to a delay associated with red houselights and then food. The delay was adjusted over trials to estimate an indifference point--a delay at which the ...
Rudski J M - - 1995
Opiate administration increases short-term free feeding in satiated rats. The feeding effects of the mixed opioid receptor agonist/antagonist buprenorphine were examined in both free-feeding and operant chamber paradigms. Buprenorphine (0.1 and 0.3 mg/kg) produced significant increases in short-term free feeding (i.e., 4 h), an effect enhanced by repeated administration. Buprenorphine's ...
Kerwin M E - - 1995
Behavioral economic concepts were applied to the analysis and treatment of pediatric feeding disorders in a clinical setting. In Experiment 1, children who chronically refused food were presented with varying amounts of food on a spoon (empty, dipped, quarter, half, and level). Each child exhibited a different but orderly demand ...
Cooper L J - - 1995
We evaluated the separate components in treatment packages for food refusal of 4 young children. First, treatment packages were implemented until food acceptance improved. Next, a component analysis was conducted within a multielement or reversal design to identify the active components that facilitated food acceptance. The results indicated that escape ...
McCarthy D - - 1995
Six pigeons were trained on a delayed red-green matching-to-sample task that arranged four delays within sessions. Matching responses intermittently produced either 1.5-s access to food or 4.5-s access to food, and nonmatching responses produced either 1.5-s or 4.5-s blackout. Two phases were conducted: a signaled phase in which the reinforcer ...
McLean A P - - 1995
Behavioral momentum theory relates resistance to change of responding in a multiple-schedule component to the total reinforcement obtained in that component, regardless of how the reinforcers are produced. Four pigeons responded in a series of multiple-schedule conditions in which a variable-interval 40-s schedule arranged reinforcers for pecking in one component ...
Hodgson D M - - 1994
Exposure to non-contingent food delivery has been shown to elicit an increase in nociceptive thresholds in rats. The conditions which elicit analgesia are similar to those that elicit schedule-induced polydipsia. In both instances animals are food-deprived and receive food on an intermittent schedule. Interpellet interval has been found to be ...
Cousins M S - - 1994
This experiment was undertaken to provide a pharmacological characterization of performance on a task involving food-related instrumental and consummatory behavior. Rats were tested in an operant chamber in which there was a choice between pressing a lever to receive a preferred food (Bioserve pellets) or approaching and consuming a less-preferred ...
Belke T W - - 1994
Pigeons' choices between a reliable alternative that always provided food after a delay (i.e., 100% reinforcement) and an unreliable one that provided food or blackout equally often after a delay (i.e., 50% reinforcement) was studied using a discrete-trials concurrent-chains procedure modified to prevent choice between alternatives following a blackout outcome. ...
Gibbon J - - 1994
Several theories in the learning literature describe decision rules for performance utilizing ratios and differences. The present paper analyzes rules for choice based on either delays to food, immediacies (the inverse of delays), or rates of food, combined factorially with a ratio or difference comparator. An experiment using the time-left ...
Rudski J M - - 1994
Naloxone's effects on initiation, maintenance, and maximal response effort to acquire food were examined in rats maintained under different levels of food deprivation. In Experiment 1, naloxone was administered SC to rats responding under an FR 80 (first pellet) FR 3 (subsequent pellets) reinforcement schedule. Naloxone did not increase time ...
Brunner D D New York State Psychiatric Institute, New York - - 1994
Choice between a variable and a fixed food source was studied in pigeons. The variable source yielded different durations of access to food (changed across experimental conditions) uniquely associated with equiprobable delays of either 20 s or 60 s, timed from the choice point. A comparison, elapsing alternative (time-left procedure, ...
Allan R W - - 1994
The pigeon's key-pecking response is experimentally dissociable into transport (head movement) and gape (jaw movement) components. During conditioning of the key-pecking response, both components come under the control of the conditioned stimulus. To study the acquisition of gape conditioned responses and to clarify the contribution of unconditioned stimulus (reinforcer) variables ...
Avila R - - 1994
Three rats, lever pressing for food delivered on a fixed-interval 128-s schedule, were presented with a 16-s opportunity to drink from a retractable water source. The temporal placement of the water probe within the reinforcement cycle was varied sequentially, in steps of 16 s. Although the lever-pressing pattern was modulated ...
Rudski J M - - 1994
Methadone administration is reported to increase food intake in studies examining free feeding and to decrease food reinforced operant responding. In light of this apparent paradox, the present study evaluated methadone's effects on food reinforced operant responding under conditions more typical of free feeding studies than operant studies. The effect ...
Foltin R W - - 1994
In a study examining "demand" for food, responding of 8 adult male baboons (Papio c. anubis) was maintained under a fixed-ratio schedule of food reinforcement during daily 23-hr experimental sessions. Completion of the ratio requirement resulted in the delivery of one, five, or 10 1-g food pellets. Supplemental feeding was ...
Nir I - - 1994
1. In an attempt to quantify the effects of "degree" of pelleting, two experiments were conducted. Diets were prepared by mixing together a mash composed mainly of maize (experiment 1) or sorghum (experiment 2) with soft pellets, or soft pellets mixed with hard pellets. 2. The pelleting degrees (PDs) were ...
Kiyatkin E A - - 1994
High-speed chronoamperometry and monoamine-selective electrochemical probes were used to monitor, during each of 5-6 consecutive daily sessions, changes in dopamine (DA)-related oxidation current in nucleus accumbens (NAcc) of rats lever-pressing for a food reward. In trained animals, the first lever-press of each session was preceded by a gradual increase in ...
Bauer L O - - 1994
Electroencephalographic (EEG) and subjective reactions to cocaine cues were evaluated in 18 cocaine-dependent outpatients, after 14 or fewer days of abstinence, and 16 noncocaine-dependent controls. EEG activity and desire for cocaine were recorded while subjects viewed three 5-min films that featured either cocaine-associated, erotic, or neutral stimuli. Other measures of ...
McSweeney F K - - 1994
Pigeons' key pecking was reinforced by food delivered by several fixed-interval, variable-ratio, and differential-reinforcement-of-low-rate schedules. Rate of responding, number of responses per reinforcer, length of postreinforcement pause, running response rate, and the time required to collect an available reinforcer changed systematically within sessions when the schedules provided high rates of ...
Urcuioli P J - - 1994
Four experiments examined control over choice by differential sample responding in matching-to-sample with differential outcomes. In Experiment 1, pigeons initially learned to match with food versus no-food outcomes. Their performances later transferred to other samples to which responding versus not responding had been explicitly reinforced with a single outcome (food). ...
Gee P - - 1994
Operant temporal discrimination learning was investigated in goldfish. In the first experiment, there was a fixed daily change in illumination. Eight subjects were trained to operate a lever that reinforced each press with food. The period during which responses were reinforced was then progressively reduced until it was 1 hr ...
Peeke H V - - 1994
In a model emphasizing prebreeding cocaine administration, rats exposed to cocaine (50 mg/kg) daily were compared to saline-injected and noninjected controls with respect to weight changes, food and water intake, maternal behavior, offspring weight, and activity. During the first 21 days cocaine-treated dams lost weight, while the control dams gained. ...
Tobin H - - 1994
Data from six previous studies of self-control behavior were compared against predictions made by the matching law and by molar maximization. The studies involved pigeons (Columba livia), rats (Rattus norvegicus), and 3-year-old, 5-year-old, and adult humans (Homo sapiens) who had received food as the reinforcer, and adult humans who had ...
Burke T F - - 1994
Lorazepam and alprazolam produced dose-dependent decreases in the rate of fixed-ratio (FR) 20 schedules of food presentation in which either a nose-poke or a lever-press defined the operant and under a fixed-interval (FI) 2-min lever-press schedule of food presentation. In contrast, under FI 2-min and differential reinforcement of low response ...
Jones B M - - 1994
The differential-outcomes effect is manifest as more accurate performance of a delayed conditional discrimination when alternative choice responses are followed by different reinforcers than when they are followed by the same reinforcer. In Experiment 1, a differential-outcomes effect was demonstrated within sessions by signaling the duration of food access for ...
Moore N.A. - - 1994
The effects of the "atypical" antipsychotic olanzapine and several other antipsychotics were examined using a conflict schedule. Rats were trained to respond for food on a three-component schedule, comprising variable-interval 30s (food, VI30) and fixed-ratio 10s (food + shock, FR10) components separated by time-out (TO). Olanzapine (0.3125-1.25mg/kg), clozapine (1.25-5mg/kg) and ...
Johnson C R - - 1994
Pica and scavenging are serious, sometimes life-threatening behavior problems among a significant percentage of individuals with mental retardation. This study describes procedures developed to reduce life-threatening pica and food scavenging in two adolescents with severe to profound mental retardation. Treatment was designed to teach the subjects to discriminate safe from ...
Bouton M E - - 1994
Four experiments with rats examined the effects of a context switch on inhibition that was acquired during a feature-negative discrimination. A target conditioned stimulus was paired with food when it was presented alone but occurred without food when it was combined with a feature stimulus. A context switch following training ...
Davison M - - 1994
Six pigeons were trained on two- and three-alternative concurrent schedules in which the alternatives were signaled by different wavelengths of light on the main pecking key. The schedules were arranged according to a switching-key procedure in which pecks on a white side key produced a 3-s blackout and, intermittently, a ...
Hoch T - - 1994
Chronic food refusal has traditionally been treated with forced feeding and other physical prompting-based procedures when positive reinforcement procedures prove inadequate. Potential problems with such procedures, however, include exacerbation of feeding difficulties and health risks, as well as low parental approval and probability of implementation. Contingency contacting maximizes contact between ...
Shimp C P - - 1994
Pigeons chose between green side keys, then waited a shorter or longer time before pecking a center key, and finally chose between red side keys. Two successive left choices (to green and then red) with a shorter wait intervening, or 2 successive right choices with a longer wait intervening, were ...
Lerman D C - - 1994
Certain responses of both humans and nonhumans appear to be maintained indirectly by intermittent reinforcement schedules and have been referred to collectively as adjunctive behavior. Although basic research has examined adjunctive behavior extensively, relatively few studies have been conducted with humans, particularly those with developmental disabilities who often engage in ...
Petry N M - - 1994
This experiment examined the relationship between two qualitatively different reinforcers and the parameters of a quantitative model of reinforced responding, referred to as the response-strength equation or the Herrnstein equation. A group of rats was first food deprived and later water deprived. An 11.5% sucrose solution served as the reinforcer ...
Foltin R.W. - - 1993
In a study examining the effects of pharmacological manipulations on "demand" for food, responding of six adult male baboons (Papio c. anubis) was maintained under a fixed-ratio schedule of food reinforcement during daily 22h experimental sessions. Increasing the response requirement decreased daily food intake. Administration of anorectic drugs (amphetamine, fenfluramine, ...
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