Biomedical subjects

A Poling

Publications and source records attributed to A Poling.

At least 37 records · Page 2Linked to original sources

PubMed1994

The effects of d-amphetamine and diazepam on schedule-induced defecation in rats.

The effects of d-amphetamine (0.32 to 5.6 mg/kg) and diazepam (0.10 to 5.6 mg/kg) on defecation were examined in two groups of rats. One group was exposed to a fixed-time 60-s (FT 60-s) schedule of food delivery and the other group was exposed to massed-food sessions. During vehicle control sessions, rats exposed to the FT 60-s schedule excreted a significantly higher number of fecal boli than rats exposed to massed-food sessions. d-Amphetamine, at doses above 0.56 mg/kg, significantly reduced defecation (boli produced) in both groups, although the magnitude of the drug's effect was larger in the group exposed to the FT 60-s schedule. For both groups, diazepam only produced a significant decrease in defecation at the highest dose (5.6 mg/kg). These results appear to be inconsistent with interpretations of adjunctive behavior that emphasize arousal or emotion as mechanisms.

Animals↗

PubMed1994

Effects of cocaine on fixed-ratio responding of rats: modulation by required response force.

The effects of acute cocaine administrations (5.6-32 mg/kg) were determined in rats responding under a multiple fixed-ratio 15 (FR 15) FR 15 schedule of food delivery. The minimum response effort required in one schedule component was 25 g, whereas in the other component it was 200 g. Cocaine produced generally dose-dependent decreases in rate of responding and increases in preratio pause time under each component. There was, however, a significant interaction between force and drug dose, and drug effects were larger in the component requiring 200 g for lever operation. Although a number of other parameters have been shown previously to modulate the effects of cocaine on schedule-controlled responding, the present data constitute the first demonstration that minimum response effort does so.

Animals↗

PubMed1994

Self- and cross-citations in the Journal of Applied Behavior Analysis and the Journal of the Experimental Analysis of Behavior: 1983-1992.

We examined self- and cross-citation practices in JABA and JEAB from 1983 through 1992. Mean levels of self-citation for JABA and for JEAB were 22.6% and 36.1%, respectively. Overall, 2.4% of JABA citations were JEAB articles, and 0.6% of JEAB citations were JABA articles, which suggests limited integration of basic and applied research.

Journal Article↗

PubMed1993

MDMA and memory: the acute and chronic effects of MDMA in pigeons performing under a delayed-matching-to-sample procedure.

The purpose of the present study was to examine the acute and chronic effects of (+/-)3,4-methylenedioxy-methamphetamine (MDMA) in pigeons responding under a delayed-matching-to-sample procedure with 0-, 3-, and 6-s delays. In the absence of drug, accuracy (percent correct responses) was inversely related to delay length. When administered pre-chronically, MDMA (0.32-5.6 mg/kg) generally decreased accuracy and response rates at doses of 3.2 mg/kg and above. Although humans report a distinct "hangover" when exposure to MDMA ends, performance of pigeons in the present study did not deteriorate when the chronic regimen ended, indicating an absence of behavioral dependence on the drug. Tolerance developed following chronic exposure to 3.2 mg/kg. In general, greater tolerance occurred at the 0-s delay than at longer delays. Although MDMA is reported to have neurotoxic effects, it does not inevitably produce long-lasting or cumulative behavioral impairment.

Animals↗

PubMed1993

Effects of d-amphetamine, methaqualone, and phencyclidine on the reaction time of pigeons.

The effects of acute administrations of d-amphetamine (0.56, 1.0, 1.78, 3.2, and 5.6 mg/kg), methaqualone (5.6, 10, 18, 32, and 56 mg/kg), and phencyclidine (0.3, 0.56, 1.0, and 1.78 mg/kg) on the reaction time of pigeons were examined. In the reaction time assay, birds were trained to depress and hold a foot treadle until a stimulus change occurred. Releases within 2 s of the stimulus change were reinforced with food; premature releases or releases occurring after the 2-s limited hold were not reinforced. At relatively high doses, each of the drugs decreased the percentage of responses that were reinforced. Methaqualone and phencyclidine usually increased median reaction times at these doses, whereas the effects of d-amphetamine on reaction time were less clear.

Animals↗

PubMed1992

Effects of d-amphetamine and ethosuximide on responding under delayed-matching-to-sample procedures with differential and nondifferential outcomes.

Pigeons were exposed to delayed-matching-to-sample (DMTS) procedures in which food or a flash of the feeder light followed correct responses. When these consequences were correlated with a particular stimulus (e.g., food followed matching responses to red and a flash of the feeder light followed matching responses to green), accuracy was higher (i.e., stimulus control was greater) than when discriminative stimuli and consequences were not correlated. Although stimulus control in the absence of drug appeared to be weaker under the uncorrelated procedure, neither d-amphetamine (0.5-3.0 mg/kg) in Experiment 1 nor ethosuximide (40-160 mg/kg) in Experiment 2 disrupted accuracy to a greater extent under that procedure. These results, like those of a prior investigation, suggest that drug effects are similar under DMTS procedures regardless of whether correlated or uncorrelated outcomes are arranged.

Animals↗

PubMed1992

Acquisition of lever-press responding in rats with delayed reinforcement: A comparison of three procedures.

The present study examined the acquisition of lever pressing in rats under three procedures in which food delivery was delayed by 4, 8, and 16 seconds relative to the response. Under the nonresetting delay procedure, food followed the response selected for reinforcement after a specified interval elapsed; responses during this interval had no programmed effect. Under the resetting procedure, the response selected for reinforcement initiated an interval to food delivery that was reset by each subsequent response. Under the stacked delay procedure, every response programmed delivery of food t seconds after its occurrence. Two control groups were studied, one that received food immediately after each lever press and another that never received food. With the exception of the group that did not receive food, responding was established with every procedure at every delay value without autoshaping or shaping. Although responding was established under the resetting delay procedure, response rates were generally not as high as under the other two procedures. These findings support the results of other recent investigations in demonstrating that a response not previously reinforced can be brought to strength by delayed reinforcement in the absence of explicit training.

Journal Article↗

PubMed1991

The effects of phenobarbital on responding under delayed-matching-to-sample procedures with differential and nondifferential outcomes.

Pigeons were exposed to delayed-matching-to-sample procedures in which food or a flash of the feeder light followed correct responses. When these consequences were correlated with a particular stimulus (e.g., food followed matching responses to red and a flash of the feeder light followed matching responses to green), accuracy was significantly higher (i.e., stimulus control was greater) than when discriminative stimuli and consequences were not correlated. Acute administrations of phenobarbital (10-40 mg/kg) produced similar effects regardless of whether or not differential outcomes were arranged for correct responses to a particular stimulus. At doses of 30 and 40 mg/kg, phenobarbital significantly decreased accuracy under both variations of the delayed-matching-to-sample procedure. Given these results, it appears that degree of stimulus control in the absence of drug did not modulate drug effects in the present study.

Animals↗

PubMed1991

Choice by rats for enriched versus standard home cages: Plastic pipes, wood platforms, wood chips, and paper towels as enrichment items.

The purpose of the present study was to determine whether simple additions to the home cages of rats made those cages preferable to standard housing arrangements. Results indicated that most rats preferred cages with wood platforms, wood chips, and paper towels to otherwise identical cages without these items. Wood chips were not, however, practical with the cages used in the present study. Plastic pipes caused no problems but were not preferred by most animals. Both wood platforms and paper towels created no problems and appeared to be useful as enrichment items. The latter were preferred to the former in a direct comparison.

Journal Article↗

PubMed1990

Discriminative stimulus properties of phenytoin in the pigeon: determination via a cumulative dosing procedure.

Pigeons were trained in a cumulative dosing procedure to emit one response in the presence of 15 mg/kg phenytoin and another response in the absence of phenytoin. After reliable discrimination was established, generalization tests with other anticonvulsant drugs were conducted. Ethosuximide (20-120 mg/kg) and methsuximide (25-100 mg/kg) engendered very little phenytoin-appropriate responding. Clonazepam (0.125-1 mg/kg) engendered more phenytoin-appropriate responding, but less than the training dose of phenytoin. Similar results were obtained when these drugs were administered in conventional single dose per session generalization tests. When tested in that fashion, mephenytoin (80 and 160 mg/kg) engendered some phenytoin-appropriate responding, but less than the training dose of phenytoin. Administering 10 mg/kg pentylenetetrazol in combination with 5, 10, 15, and 20 mg/kg cumulative doses of phenytoin reduced phenytoin-appropriate responding relative to levels obtained with these doses of phenytoin alone.

Animals↗

PubMed1990

Free birds aren't fat: Weight gain in captured wild pigeons maintained under laboratory conditions.

Nine feral pigeons, 5 from an urban setting and 4 from a rural setting, were captured and maintained for 42 days under free-feeding conditions comparable to those arranged for laboratory subjects. On average, birds increased their body weights by 17% over this period. The range of increase across birds was 9 to 30%. These findings suggest that the food deprivation arranged for laboratory pigeons, which is characteristically 80% of free-feeding weights, may in some sense be less severe than it first appears.

Journal Article↗

PubMed1990

Neuroleptics and learning: effects of haloperidol, molindone, mesoridazine and thioridazine on the behavior of pigeons under a repeated acquisition procedure.

The purpose of the present study was to examine the effects of haloperidol (0.3-10 mg/kg), molindone (0.3-5.6 mg/kg), mesoridazine (0.3-10) and thioridazine (0.3-25 mg/kg) on the behavior of pigeons exposed to a repeated acquisition procedure. At sufficiently high doses, each of these neuroleptics increased error rates (interfered with learning) and reduced rate of responding. When the drugs were compared on the basis of absolute doses administered, haloperidol disrupted behavior at doses considerably lower than the other drugs. If, however, chlorpromazine equivalent doses were examined, haloperidol was the least disruptive of the four drugs. Comparing the degree of behavioral disruption produced by the four drugs with their relative neuroreceptor affinities for dopamine D-2, cholinergic muscarinic, histamine H1, alpha-1 adrenergic and alpha-2 adrenergic receptors suggests that behavioral disruption cannot be attributed in any simple way to dopamine or acetylcholine receptor blockade. The relationship between the behavioral effects of neuroleptics and their simple neuropharmacological actions must be considered as highly tentative.

Animals↗

PubMed1989

Pentylenetetrazol-induced seizures in pigeons and the effects of ethosuximide thereon.

Previous research has shown that ethosuximide in high enough doses disrupts operant responding in pigeons. Whether or not these same doses protect against seizure activity in this species has not been determined. In the present study a system for scoring pentylenetetrazol-induced seizures in pigeons was developed and the effects of ethosuximide on such seizures were evaluated. Pentylenetetrazol at 15, 27 and 47 mg/kg reliably induced seizures in Experiment 1. In Experiment 2 six doses of ethosuximide were tested for their seizure-controlling effectiveness. Doses of 20, 40, 80, 160 and 320 mg/kg ethosuximide had little effect on seizures induced by 27 mg/kg pentylenetetrazol; 640 mg/kg significantly reduced but did not completely eliminate seizures. This dose (640 mg/kg) is several times higher than the doses found to disrupt operant behavior in our previous studies.

Animals↗

PubMed1989

Effects of Ro 15-4513 on schedule-controlled responding of pigeons.

The partial inverse benzodiazepine agonist Ro 15-4513 has been found to antagonize some of the behavioral and physiological effects of ethanol, but relatively little is known about the behavioral effects of the drug alone. In the present study, pigeons responding under a multiple fixed-ratio 25 interresponse-time-greater-than-6-sec schedule of food delivery were exposed acutely and chronically to Ro 15-4513. Acute administrations of the drug (1.0, 1.8, 3.2, and 5.4 mg/kg) reduced response rates under the fixed-ratio component at some doses, although two birds were more sensitive to the drug than the third subject. Response rates under the interresponse-time-greater-than-6-sec component were not affected by acute administrations of Ro 15-4513. When 5.4 mg/kg Ro 15-4513 was administered prior to 15 consecutive sessions, tolerance developed to the rate-reducing effects of the drug under the fixed-ratio component. These findings, in contrast to those of early investigations in which gross measures of behavior were employed, suggest that Ro 15-4513 is behaviorally active at relatively low doses.

Animals↗

PubMed1989

Effects of phenytoin and phenobarbital on schedule-controlled responding and seizure activity in the amygdala-kindled rat.

The purpose of the present study was to examine whether doses of phenytoin and phenobarbital that blocked kindled seizures in rats also disrupted operant behavior. Subjects initially were exposed to a kindling procedure in which repeated electrical stimulation of the amygdala evoked generalized seizures. After kindling, they were trained under a multiple fixed-ratio 30 interresponse-time-greater than 10-sec schedule of food delivery. Once each day, 6 days per week, 30-min exposures to this schedule were followed immediately by amygdaloid stimulation which occurred at no other time. Response rate, reinforcement rate and duration of forelimb clonus were recorded. When response rates were stable, 5 rats were tested with phenytoin (25, 50, 75 and 100 mg/kg) and 5 others were tested with phenobarbital (10, 25 and 40 mg/kg). Results indicated that doses of phenytoin that controlled kindled seizures also affected operant behavior. For this drug, the ED50 for forelimb clonus was 62 mg/kg. For response rate under the fixed-ratio and interresponse-time components, it was 48 and 58.2 mg/kg, respectively. Dose-response curves for the behavioral and antiseizure effects of phenobarbital were similar. However, for this drug the ED50 for forelimb clonus (18.9 mg/kg) was significantly lower than for response rate under the fixed ratio component (37.4 mg/kg).

Amygdala↗

PubMed1988

Effects of methsuximide and mephenytoin on the responding of pigeons under a fixed-consecutive-number schedule with and without an external discriminative stimulus.

The effects of the antiepilepsy drugs methsuximide and mephenytoin were examined in pigeons responding under a fixed-consecutive-number (FCN) schedule with and without an added external discriminative stimulus. On this schedule, food was delivered whenever subjects responded between 8 and 12 times on one response key (work key), and then responded once on a second response key (reinforcement key). Under one variant of the FCN schedule (FCN 8-SD), an external discriminative stimulus signalled completion of the response requirement on the work key; no such stimulus change occurred under the other (FCN 8) schedule. The two FCN schedules (with an without stimulus change) alternated at 5-min intervals within each session for all subjects. Methsuximide (25-200 mg/kg) and mephenytoin (40-160 mg/kg) produced generally dose-dependent decreases in percentage of reinforced response runs and rate of responding. The magnitudes of these effects were comparable under both variants of the FCN schedule.

Animals↗

PubMed1988

Acute and chronic effects of methsuximide and mephenytoin on the delayed-matching-to-sample performance of pigeons.

Acute and chronic effects of methsuximide and mephenytoin were examined in pigeons performing under a delayed-matching-to-sample procedure. Acute administrations of methsuximide (25-175 mg/kg) and mephenytoin (40-160 mg/kg) produced generally dose-dependent decreases in accuracy. At the two highest doses, methsuximide decreased rate of responding to the sample stimulus; mephenytoin did so only at the highest dose. At low doses, both methsuximide and mephenytoin increased response rate over control. After 20 sessions of daily exposure to methsuximide (100 mg/kg) or mephenytoin (80 mg/kg), tolerance developed to the accuracy-decreasing effects of both drugs.

Animals↗

PubMed1988

Effects of methsuximide on schedule-controlled responding in the pigeon.

Acute and chronic effects of methsuximide (25, 50, 75, and 100 mg/kg), a succinimide with anticonvulsant properties, were examined in pigeons responding under a multiple fixed-ratio 50 fixed-interval 90-sec schedule of food delivery. The clearest acute effect of methsuximide was a substantial reduction in response rates under both components of the multiple schedule when the drug was administered at 100 mg/kg. Detailed analysis of the temporal distribution of responding under the fixed-interval failed to reveal rate-dependent drug effects. Tolerance appeared to develop to the effects of methsuximide when the drug was administered chronically.

Animals↗