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Biomedical subjects

A Poling

Publications and source records attributed to A Poling.

At least 91 records · Page 5Linked to original sources
PubMed1981

d-Amphetamine and phencyclidine alone and in combination: effects on fixed-ratio and interresponse-time-greater-than-t responding of rats.

The effects of three doses of d-amphetamine (0.5, 1.0, and 2.0 mg/kg) and phencyclidine (0.5, 1.0, and 2.0 mg/kg), alone and in combination, were assessed in rats performing under fixed-ratio 30 and interresponse-time-greater-than-15-sec food reinforcement schedules. When given alone, phencyclidine and d-amphetamine produced similar increases in responding under the interresponse-time-greater-than-t schedule, and decreases in responding under the fixed-ratio 30 schedule. Each drug decreased the number of reinforcers (food pellets) earned relative to control values under both schedules. The effects of the two drugs in combination were nearly always less than additive. That is, the effects of a given dose of phencyclidine and d-amphetamine together were less than an arithmetic summation of the effects of the drugs given alone.

Animals↗
PubMed1981

Burying by rats in response to aversive and nonaversive stimuli.

Previous investigations have shown that rats bury a variety of conditioned and unconditioned aversive stimuli. Such burying has been considered as a species-typical defensive reaction. In the present studies, rats buried spouts filled with Tabasco sauce, or condensed milk to which a taste aversion was conditioned, but did not bury water-filled spouts or spouts filled with a palatable novel food (apple juice) to which a taste aversion was not conditioned. However, in other experiments rats consistently and repeatedly buried Purina Rat Chow, Purina Rat Chow coated with quinine, and glass marbles. This indicates that a variety of stimuli, not all aversive or novel, evoke burying by rats. Whereas the behavior may reasonably be considered as a species-typical defensive behavior in some situations, the wide range of conditions that occasion burying suggests that the behavior has no single biological function.

Journal Article↗
PubMed1980

Water intake induced by spaced deliveries of salted and sweetened liquid food.

The water intake of food-deprived rats was evaluated under conditions where liquid food was presented occasionally. In the first experiment, when soybean milk alone was presented every 30 sec, little water was consumed. However, when sodium chloride was added to the soybean milk, water intake increased directly with salt concentration from 0.9 to 14.4%. At salt concentrations of 7.2 and 14.4%, the drinking induced by soybean milk resembled in several respects the adjunctive drinking educed by spaced presentations of dry food. In a second experiment, adulterating soybean milk with sugar in concentrations of 7 to 56% did not affect water intake significantly when the food was delivered every 30 seconds. These findings extend the range of conditions known to generate schedule-induced drinking, and point out a previously unknown constraint on the phenomenon.

Animals↗
PubMed1980

The use of human observers in psychopharmacological research.

During 1974-1978, over 40% of the nonhuman drug studies that appeared in Psychopharmacology, Pharmacology Biochemistry and Behavior, and Journal of Pharmacology and Experimental Therapeutics involved human observers; far fewer studies published in Journal of the Experimental Analysis of Behavior did so. In all of these journals, measures of interobserver agreement seldom were provided. The great majority of studies also failed to utilize one or more "blind" observers, unaware of experimental conditions. These findings are of interest in light of reports that observational data are affected by a wide range of factors and often provide an inaccurate index of behavior. The believability of observational data seemingly is enhanced by careful descriptions of recording procedures coupled with the use of two or more blind observers whose concordance in rating behavior has been determined. These procedures characteristically are followed in some behavioral sciences, such as applied behavior analysis, but not to the same degree in psychopharmacology.

Animals↗
PubMed1980

d-Amphetamine, operant history, and variable-interval performance.

The effects of d-amphetamine on the bar-pressing of rats maintained under a variable-interval schedule of water reinforcement were examined as a function of the operant history of the subjects. One group of rats initially received 51 sessions of exposure to a fixed-ratio 20 schedule, while a second group received equivalent exposure to an interresponse-time-greater-than-12-sec schedule. Mean group response rate when stable was over ten times as high under the fixed-ratio schedule as under the interresponse-time-greater-than-12-sec schedule. Response rates of the two groups largely converged across 47 sessions of exposure to a variable-interval 60-second schedule, at which time response rates for both groups appeared stable. Acute administration of d-amphetamine sulfate similary affected mean response rates of both groups: A 0.25 mg/kg dose did not obviously affect rate, while doses of 0.5, 1.0, and 2.0 mg/kg produced dose-dependent rate decreases. These results indicate that the efficacy of operant history as a determinant of drug effects may be limited to circumstances where current contingencies do not exercise powerful and direct control over behavior.

Animals↗
PubMed1980

Polydipsia induced by intermittent delivery of salted liquid foods.

Food-deprived rats given constant access to water were exposed to fixed-time presentations of soybean milk and diluted sweetened condensed cows' milk. In some conditions these liquid foods were adulterated with varying amounts of sodium chloride. Under a fixed-time 30-sec schedule of food delivery, little water was consumed when the food was soybean milk alone, or soybean milk with sodium chloride added in concentrations of .9, 1.8, or 3.6%. However, schedule-induced polydipsia appeared when soybean milk adulterated with 7.2 or 14.4% sodium chloride was delivered under this schedule. When soybean milk containing 7.2% sodium chloride was presented under fixed-time 15-, 30-, 60-, 120-, and 240-sec schedules, schedule-induced drinking increased with the fixed-time value from 15 to 120 seconds, and decreased at 240 seconds. Like soybean milk, diluted sweetened condensed milk delivered under fixed-time schedules of 30, 60, and 120 seconds failed to evoke schedule-induced polydipsia, but did so when adulterated with 7.2% sodium chloride. Drinking induced by salted liquid foods resembled the polydipsia engendered by spaced dry-food presentations in several ways, including temporal relation to food delivery, persistence within and across sections, sensitivity to interfood interval, and magnitude relative to intake evoked by bulk-food presentation.

Animals↗
PubMed1979

Drug effects on the performance of pigeons under a negative automaintenance schedule.

Pigeons were exposed to a negative automaintenance schedule in which food was delivered following brief key illumination only if the illuminated key was not contacted; contact of the lighted key prevented food delivery. All subjects emitted some responses under this procedure when drugs were not given. However, the number of responses was less than that which occurred under an automaintenance procedure in which food followed key illumination regardless of the bird's behavior. Under the negative automaintenance procedure, acute administration of atropine (0.01--0.1 mg/kg), d-amphetamine (0.4--1.6 mg/kg), and morphine (3,8--15 mg/kg) reduced in a dose-dependent manner the percentage of key illuminations in which subjects contacted the lighted key. Diazepam (1.0--6.0 mg/kg) increased the percentage of key illuminations during contact responses occurred.

Animals↗
PubMed1978

Effects of quipazine on behavior under a multiple schedule of reinforcement.

The effects of three doses of quipazine (1.0, 5.0 and 10.0 mg/kg) on the performance of rats under a multiple fixed-ratio 15 fixed-interval 60-sec schedule of food reinforcement were examined. In the absence of drug, response rates under the fixed-ratio component were much higher than response rates under the fixed-interval component. Rates under the fixed-ratio component were decreased by quipazine in dose-dependent fashion, while response rates under the fixed-interval component were increased by the lowest dose and decreased by the two higher doses of the drug.

Animals↗
PubMed1978

Drug effects under automaintenance and negative automaintenance procedures.

Three food-deprived pigeons were initially exposed to an automaintenance procedure in which brief periods of response key illumination were followed by food delivery without regard to the subject's behavior. Keypecking occurred at a high rate while the key was illuminated and was reduced in dose-dependent fashion by acute administration of LSD (0.05--0.45 mg/kg), quipazine (1.0--8.0 mg/kg), haloperidol (0.08--0.32 mg/kg), and pentobarbital (4.0--16.0 mg/kg). The animals were then exposed to a negative automaintenance procedure in which food delivery followed key illumination only if the lighted key was not contacted. Keypecking occurred at a low rate under this procedure, with no responses occurring during the majority of key illuminations and was decreased or unaffected by LSD, quipazine, and haloperidol; pentobarbital increased responding at doses of 4.0 mg/kg and 8.0 mg/kg and reduced responding at a dose of 16.0 mg/kg.

Animals↗
PubMed1978

d-amphetamine and fixed-interval performance: effects of operant history.

Sixteen rats were initially exposed for 50 sessions to either a fixed-ratio 40 or an interresponse-time-greater-than-11-second food reinforcement schedule, then shifted to a fixed-interval 15-second food reinforcement schedule. Animals with fixed-ratio 40 histories lever pressed at much higher rates under the fixed-interval schedule than did animals with inter-response-time-greater-than-11-second histories. This difference persisted across 93 sessions of fixed-interval exposure. The effects of d=amphetamine were assessed after 15 and 59 sessions of fixed-interval exposure. On both occasions, the low-rate responding of animals with interresponse-time-greater-than-11-second histories was typically increased by all doses of the drug, while the high-rate responding of animals with fixed-ratio 40 histories was typically decreased by all doses of the drug. These results suggest that control response rate under the fixed-interval schedule, which may be affected by a history of responding under another schedule, is the primary determinant of the relative effects of d-amphetamine.

Animals↗
PubMed1978

Performance of rats under concurrent variable-interval schedules of negative reinforcement.

The behavior of rats under concurrent variable-interval schedules of negative reinforcement was examined. A single one-minute variable-interval programmer determined the availability of 30-second timeouts from electric shock. These were assigned to one or the other of the two component schedules with a probability of 0 to 1.0. The response requirement for the component schedules was standing to the right or left of the center of the experimental chamber. With a six-second changeover delay, the relative time spent under one component schedule varied directly and linearly with the relative number of timeouts earned under that component schedule. The absolute number of changeovers was highest when a similar number of timeouts was earned under each component schedule, and lowest when all or nearly all timeouts were earned under one component schedule. In general, these relations are similar to those reported with concurrent variable-interval schedules of positive reinforcement.

Journal Article↗
PubMed1978

Automaintenance in guinea pigs: effects of feeding regimen and omission training.

Behavior maintained by stimulus-reinforcer pairings was examined. Guinea pigs maintained at 85 per cent of free-feeding weights reliably contacted a retractable lever presented before delivery of a single piece of guinea-pig chow or a 45-milligram guinea-pig pellet. When animals were given free access to one food and received the second food preceded by the lever, contact responses persisted. Such responses seldom occurred when a single food was freely available and was also delivered after lever presentation. Introduction of an omission training (negative automaintenance) procedure, in which lever contacts resulted in lever retraction and prevented food delivery, strongly reduced lever contacts. Observation indicated that mouthing the food cup, instead of the lever, became the prominent behavior during the prefood stimulus under the omission training procedure.

Journal Article↗
PubMed1977

The effects of d-amphetamine on the automaintained key pecking of pigeons.

Three food-deprived pigeons were initially exposed to an automaintenance procedure in which 8-s response key illuminations were followed by food delivery without regard to the subject's behavior. The percentage of occasions on which key illumination was followed by food delivery was then successively reduced from 100 to 50, 25, 10, and 2.5%. Despite the lack of a programmed contingency between key pecking and food delivery or key illumination, key pecking occurred under all automaintenance conditions. Mean responses per 8-s key illumination during non-drug sessions varied from over 15 to less than one, with the 100 and 50% pairing conditions engendering the highest rates and the 2.5% pairing condition the lowest. Under all automaintenance conditions, d-amphetamine in does of 0.5, 1, and 2 mg/kg decreased responding in a dose-dependent fashion. Rate-dependent effects were not evident despite the appreciable differences in mean response rates engendered by the various conditions.

Animals↗
PubMed1977

Effects of delaying food availability contingent on ethanol-maintained lever pressing.

The effects of delaying food availability 8 s contingent on every, every second, and every fourth lever press maintained by 4,8, and 16% (v/v) ethanol solutions were examined when food was initially available to rats on a fixed-interval 26-s schedule. The delay contingency decreased ethanol-maintained responding at all ethanol concentrations, with the degree of decrease inversely related to the intermittency of the delay schedule and to the ethanol concentration. Such decreases were not evident in the performance of yoked-control animals which received food coincidentally with experimental animals. Temporal changes in food presentation alone therefore could not account for the decreases produced by the delay contingency.

Animals↗
PubMed1977

Effects of d-amphetamine and chlordiazepoxide on positive conditioned suppression.

Six rats lever-pressed under a variable-interval 80-sec food reinforcement schedule. After responding had stabilized, an 8-sec tone terminating with food delivery was superimposed on the variable-interval schedule on the average once every five minutes without regard to the animal's behavior. This positive conditioned suppression procedure consistently reduced responding during the pre-food stimulus (tone). Neither d-amphetamine (0.5, 1.0, 2.0 mg/kg) nor chlordiazepoxide (7.5, 15, 30 mg/kg) significantly affected the relative suppression produced by the tone. Instead, both drugs produced generally non-selective effects, similarly affecting response rate in the presence and absence of the tone.

Animals↗