ISSN:0272-4391    

DOI:10.1002/ddr.430200102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractLever pressing of squirrel monkeys was maintained under second‐order schedules of either food presentation or cocaine injection. The first response after 3 min produced a 2 sec change in the color of a visual stimulus; the tenth stimulus presentation was followed by either an i.m. injection of cocaine (0.3, 1.0, or 2.0 mg/kg) or the delivery of food. The benzodiazepine chlordiazepoxide (0.3‐5.6 mg/kg) increased responding maintained by food at doses that decreased cocaine‐maintained responding. In contrast, buspirone, a novel nonbenzodiazepine anxiolytic (0.001‐0.03 mg/kg), its analog gepirone (0.003‐0.03 mg/kg), and the N serotonin 1A (5‐HT1A) agonist 8‐hydroxy‐2(di‐n‐propylamino)tetralin (8‐OH‐DPAT; 0.0003‐0.001 mg/kg) increased cocaine‐maintained responding at doses that decreased responding maintained by food. The inverse agonist at benzodiazepine receptors β‐carboline‐3‐carboxylic acid ethyl ester (βCCE) only decreased response rates irrespective of the maintaining event. m‐Chlorophenylpiperazine (mCPP), an agonist at 5‐HT1breceptors, increased responding maintained by food while only decreasing cocaine maitained responding (0.001‐0.03 mg/kg), whereas metergoline (0.1‐0.3 mg/kg), a serotonin antagonist with affinity for both 5‐HT1and 5‐HT2receptors, produced large response rate increases in both groups of monkeys. Administration of the 5‐HT2antagonist ketanserin (0.03‐3.0 mg/kg), the 5‐HT1Acompound spiroxatrine (0.0003‐0.03 mg/kg), or the nonselective 5‐HT agonist quipazine (0.003‐1.0 mg/kg) resulted in dose‐dependent response rate decreases in both groups. These results further differentiate buspirone and related compounds from typical anxiolytics and suggest a differential involvement of 5‐HTIA re

ISSN:0272-4391    

DOI:10.1002/ddr.430200103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractFood‐deprived pigeons were trained to peck a key under either a three‐component multiple random‐ratio 5, random‐ratio 25, random‐ratio 125 schedule or a three‐component multiple random‐interval 10‐sec, random‐interval 30‐sec, random‐interval 125‐sec schedule of food presentation. Following determination of acute effects of cocaine (1.0‐13.0 mg/kg), are‐sponse‐rate‐reducing dose was given before each daily session. Once performance under conditions of daily administration had become stable, other doses occasionally were substituted for the usual daily dose so that dose effects could be assessed. Tolerance, i.e., a rightward shift in the dose‐effect curve was observed in all subjects. For subjects studied under the random‐ratio schedules, however, the robustness of the tolerance usually was related to the schedule‐parameter value; tolerance was great at lower random values. By contrast, subjects whose responding was maintained by random‐interval schedules were less likely to show tolerance that was schedule‐parameter dependent. The results also provide suggestive evidence that dose may be an important factor in determining effects of repeated cocaine exposure; repeated administration of larger doses may be less likely to result in toleran

ISSN:0272-4391    

DOI:10.1002/ddr.430200104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractEffects of daily administrations ofd‐amphetamine were studied on key peck responses of pigeons maintained under a multiple fixed‐interval 2‐min, fixed‐ratio 30‐responseschedule. Under the fixed‐interval schedule, a pause was followed by a transition to increasing rates of responding until food presentation. Under the fixed‐ratio schedule, higher sustained rates of responding were maintained. Low to intermediate doses (0.3‐1.0 mg/kg) ofd‐amphetamine changed the temporal patterns and occasionally increased rates of responding under the fixed‐interval schedule. Higher doses decreased rates of responding under bothschedules. With daily injections of 1.0 mg/kgd‐amphetamine prior to experimental sessions, the effects of this dose on rates and patterns of responding were attenuated, andd‐anphetamine dose‐effect curves were shifted to the right, primarily under the fixed‐ratio schedule. Similar results were obtained with daily presession injections of 5.6 mg/kgd‐amphetamine in a second group of pigeons, except that rates of responding under both schedules were decreased by this daily dose, and did not return completely to control values with repeated injections. In a third group of pigeons, 1.0 mg/kgd‐amphetamine administered daily, after experimental sessions, did not alter dose‐effect functions ford‐amphetamine. In a second experiment, pigeons were trained to peck one response key when given 1.0 mg/kgd‐amphetamine and a different key when given presession water injections. Increasing doses of d‐amphetamine produced incresing percentages ofd‐amphetamine‐key responses. Repeated administration of 5.6 mg/kg d‐amphetamine shifted these dose‐effect functions to the right one‐half log unit. Results suggested that decreases in reinforcement frequency are not a necessary condition for the dev

ISSN:0272-4391    

DOI:10.1002/ddr.430200105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractThe present study was conducted to compare the acute effects of secobarbital (0–300 mg) and diazepam (0–30 mg) on learning in normal volunteers. The repeated acquisition of behavioral chains procedure was used to assess learning. Subjects were exposed to varying doses of secobarbital, diazepam, and placebo under double‐blind conditions. Both compounds increased overall percent errors and decreased overall response rates as an orderly function of dose. No statistically significant differences were observed between these two compounds in onset, magnitude, or duration of effects. As expected, potency differences were observed with diazepam being approximately 10 times more potent than secobarbital. Overall these results indicate that secobarbital and diazepam produce a comparable profile of effects in humans responding under a repeated acquisition of behavioral chains procedure. Thus, with regard to learning impairment, the liability associated with using or abusing secobarbital vs. diazepam appears to be the

ISSN:0272-4391    

DOI:10.1002/ddr.430200106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractOne scientific concern with benzodiazepine is their effects on learning (acquisition). One procedure that permits a detailed study of learning processes is the repeated acquisition of behavioral chains procedure. The repeated acquisition of behavioral chains allows for the repeated study of learning in individual subjects and also permits a comparison with comparable performance behavior. This paper reviews the effects of acute and chronic benzodiazepines on the repeated acquisition and performance of response chains. With acute administration, diazepam, alprazolam, and triazolam are all found to produce dose‐related increases in percent errors in the acquisitions component, while generally not affecting percent errors in the performance component. Diazepam showed less activity than either alprazolam or triazolam. With chronic administration, acquisition showed tolerance to the errors‐increasing effects of diazepam at a slower rate than did performance. Clinical implications of these findings are discus

ISSN:0272-4391    

DOI:10.1002/ddr.430200107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractTwenty‐four adult male research volunteers, in groups of three subjects each, lived in a residential laboratory for up to 18 days. All contact with the experimenters was through a networked computer system, and subject behavior was continuously monitored and recorded. During the first part of each day, subjects remained in private rooms doing planned work activities, and during the remainder of each day they were allowed to socialize. One or two cigarettes containing active marijuana (1.8‐2.7% Δ9‐THC) or placebo were smoked during both the private work period and the period of access to social activities. Following the determination of baseline distributions of activities, contingency conditions requiring subjects to engage in a low‐probability activity (instrumental activity) in order to earn time that could be spent engaging in a high‐probability activity (contingent activity) were then introduced. Baseline and contingency conditions were studied under periods of placebo and active marijuana administration. Under placebo conditions, introduction of the contingency resulted in increases in instrumental activity and decreases in contingent activity under both placebo and active marijuana conditions. The response to combining marijuana administration with contingencies varied across private work and social access conditions. During work periods, active marijuana administration increased instrumental activity to a larger extent than was observed under placebo conditions. The decreases in contingent activity were similar to those seen under placebo conditions. During social periods, active marijuana administration increased instrumental activity to a smaller extent than observed under placebo conditions. The decreases in high‐probability contingent activity were similar across drug conditions. Smoking active marijuana was thus observed to produce increments in instrumental activity under motivational involving contingencies for “work activities” while producing instrumental decrements under motivational conditions involving recreation

ISSN:0272-4391    

DOI:10.1002/ddr.430200108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractRats were trained on a complex avoidance schedule in which responses on one lever postponed shock and responses on another lever occasionally (variable‐interval 45 sec schedule) produced 2 min periods of timeout from avoidance. As shown in previous experiments, ethanol (1.5 or 2.0 g/kg) produced an increase in timeout responding relative to avoidance lever rates. These effects were attenuated in five of the six rats by 6 mg/kg RO 15‐4513, a dose that did not produce consistent intrinsic effects. In contrast, FG 7142 (10 mg/kg) reliably reversed ethanol effects in only one of the six rats tested. These results support the notion that RO 15‐4513 possesses specific ethanol antagonist prope

ISSN:0272-4391    

DOI:10.1002/ddr.430200109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractComparable patterns of behavior maintained by different events are affected similarly by certain drugs and differently by others. The present paper argues that patterns of behavior maintained by response‐produced shock (“shock‐maintained behavior”), although similar in appearance to lever pressing maintained by more conventional positive reinforcers, are generated through differential punishment of long interresponse times; hence, drug effects on this behavior should more closely resemble drug effects on pressing suppressed by punishment. Because the operants suppressed in these procedures are diametrically opposed (long interresponse times vs. pressing), the baseline patterns of behavior will differ (suppressing long interresponse times produces high rates of pressing, punishing pressing produces low rates). Furthermore, any drug‐induced changes in the frequency of the punished operant will result in what appear to be dissimilar drug effects if the rate of only one operant class serves as the dependent variable. That is, drugs that increase the rate of pressing that has been suppressed by punishment should increase long interresponse times similarly suppressed. This results in an overall increase in pressing rate under typical punishment procedures, but a decrease in overall pressing rates (an increase in the rate of punished long interresponse times) under shock‐maintenance procedures. Hence, similar drug effects on these inversely related operants should generate opposite changes in pressing rate under the two sets of procedures. A review of the literature revealed this to hold true in 12 of 15 cases. Drug effects on comparable patterns of pressing maintained by shock or food presentation split more evenly. The literature indicates that, of 21 such, comparisons between pressing maintained under fixed‐interval schedules of food or shock, ten yielded comparable drug effects under both, and 11 yielded dissimilar effects. These results suggest that what appear to be dissimilar drug effects on pressing maintained or suppressed by shock may in fact be similar effects on the inversely related operants differentiated under th

ISSN:0272-4391    

DOI:10.1002/ddr.430200110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractAcute neuroleptic administration results in within‐session decrements for conditioned active avoidance, discriminated lever release (reaction time), fixed‐ratio responding, lever pressing for intracranial electrical stimulation, licking, runway running, and treadmill running. Similarly, catalepsy has been shown to be increased by repeated testing. This paper briefly reviews these findings and reports new results on the effects of haloperidol on the micro‐characteristics of rats' operant behavior maintained by fixed‐ratio 20 food reinforcement. With these methods, within‐session decrements were seen to be produced by abrupt cessation of responding and by response slowing that was evident from the first few responses in the session. It is argued that within‐session decrements can be viewed as manifestations of neuroleptic‐induced pseudoparkinsonism in the rat and that dynamic neurochemical changes in the nigrostriatal dopamine system mediate the behav

ISSN:0272-4391    

DOI:10.1002/ddr.430200111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY