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1.
Key pecking of two pigeons was maintained under a multiple schedule of food presentation. In the presence of one keylight stimulus responding produced food according to a fixed-interval 5-min schedule. Additionally, during this component, each 50th response produced electric shock. When a different keylight stimulus was present, key pecking resulted in food delivery under a variable-interval 3-min schedule. Responding was suppressed by shock presentation (punishment) but was still positively accelerated throughout each fixed-interval cycle; steady response rates occurred during the alternate component when only the variable-interval schedule was in effect. Overall rates of punished responding were largely unchanged with d-amphetamine (0.1-3.0 mg/kg); unpunished responding was generally either increased slightly or was decreased. Pentobarbital and chlordiazepoxide (1.0-17.0 mg/kg) administered alone increased both punished and unpunished responding at most doses. Combinations of d-amphetamine with either pentobarbital or chlordiazepoxide produced increases in punished responding that exceeded those obtained with either of these drugs alone. The combined effects of d-amphetamine and either pentobarbital or chlordiazepoxide on unpunished responding depended on the individual dose combinations. Combinations of d-amphetamine with pentobarbital or chlordiazepoxide produced effects on both punished and unpunished responding that differed substantially from those obtained when any of these drugs were administered separately.  相似文献   

2.
A procedure was developed with pigeons to extend the experimental analysis of punished behavior and the effects of anxiolytic drugs. Under this procedure the completion of a fixed-ratio requirement on a changeover key switched between two variable-interval schedules of reinforcement that were programmed on a second response key. Under one schedule, correlated with a green keylight, key pecks produced only food; under the second schedule, correlated with a red keylight, key pecks produced both food and electric shock. Pigeons were switched into the component with shock if they did not enter that component within 5 min. Parameter values of the variable-interval schedules were manipulated systematically and the effects of two clinically active anxiolytic drugs, buspirone and chlordiazepoxide, were examined. Responding was suppressed during the component with shock (punishment) and, under non-drug conditions, pigeons infrequently switched into the punishment component; changeover responses occurred rapidly when switched into the punishment component. Both buspirone (0.1-3.0 mg/kg) and chlordiazepoxide (3.0-30 mg/kg) increased punished responding at doses that had little effect on unpunished responding; d-amphetamine (0.3-5.6 mg/kg), which was studied only under one parameter of the variable-interval schedule, produced greater decreases in rates of punished responding than in unpunished responding.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
Various dosages of d-amphetamine (0.1, 0.5, 2.5 mg/kg) and of cocaine (5.0, 20, 40 mg/kg) were administered i.p. to each of 7 rats trained in an experimentally induced conflict procedure. Sessions were 1 hr in duration and consisted of five 12 min periods; responding was reinforced with food on a F124 sec schedule of reinforcement during each period; however, in periods 2 and 4 each response was followed by the application of footshock. Significant increase in responding did not occur in any period following any of the pretreatments. Cocaine (5.0, 20 mg/kg) and d-amphetamine (0.5, 2.5 mg/kg) significantly decreased responding in both punished and unpunished periods. Following these treatments the rate of responding in punished and unpunished components was not significantly different. This suggest that psychomotor stimulants may not selectively increase anxiety, at least at dosages which are not at the same time anorexic.  相似文献   

4.
The effects of d-amphetamine (0.01-5.6 mg/kg i.m.) were studied on lever pressing of squirrel monkeys maintained under various second-order schedules by a visual stimulus (S) that, with separate monkeys, was occasionally paired with the presentation of either food, electric shock or with the termination of a stimulus in the presence of which shocks occurred. Under one condition, the first response after 5 min produced a 3-sec stimulus change and the fourth stimulus change was followed immediately by food delivery, electric shock presentation or by the termination of a stimulus in the presence of which shocks occurred [fixed-ratio (FR); fixed-interval (FI) [FR 4 (FI 5-min:S)]. The effects of d-amphetamine were also studied under the food- and shock-presentation schedules when food or shock occurred only once, at the end of each session, after completion of 53n 3-min fixed-intervals all of which ended with a brief stimulus change [FR 10 (FI 3-min : S)]. Under a third condition, each thirtieth response produced the 3-sec brief stimulus (FR 30 : S) and the first FR 30 completed after 5 min elapsed produced the stimulus followed by food or, with separate monkeys, electric shock [FI 5-min (FR 30:S)]. Low to intermediate doses of d-amphetamine (0.03-0.3 mg/kg) generally increased and higher doses (0.56-5.6 mg/kg) decreased responding under all conditions. The effects of d-amphetamine on responding maintained by brief stimuli under different types of second-order schedules are generally similar, regardless of the type of reinforcing event or particular second-order schedule.  相似文献   

5.
Experiment 1 examined the effects of punishment on the discriminative stimulus (DS) effects of midazolam (M) and pentobarbital (P) in 3 pigeons. Sessions began with a fixed-interval (Fl) 3-min schedule of food reinforcement. After 40 min, either saline (S) or 0.56 mg/kg of M was injected. A drug-discrimination (DD) component began 10 min later. Pecking the left key produced grain after S injections, whereas pecking the right key produced grain after M. Dose-response curves for M and P were obtained under these conditions and also when every 30th peck during the Fl was punished by shock. The introduction of punishment increased sensitivity to the DS effects of M and P. Experiment 2 examined whether a punishment history increases sensitivity to the DS effects of M. After DD training and testing, pecking was punished for 10 sessions. This history shifted the M dose-response curve to the left for 3 of 4 pigeons. These results emphasize the contribution of behavioral variables to the DS effects of drugs. Environmental variables appear to play a prominent role in guiding sensitivity to the subjective effects of drugs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
Exp I demonstrated the formation of a discriminated punishment effect in the absence of a conditioned emotional response. Electric shocks were delivered at random intervals to 3 naive male White Carneaux pigeons pecking for food on a variable-interval schedule. During a 1-min visual conditioned stimulus (CS), scheduled shocks were delayed until a response occurred (punishment). Differential suppression to the CS was observed in addition to overall suppression. Suppression was related to shock intensity. In Exp II with the same Ss, CS suppression was related to the CS and was not an artifact of response pattern or discrimination of shock patterns. The punishment contingency without the CS did not suppress behavior, and the CS without the punishment contingency did not relieve suppression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
Male Wistar rats were exposed to a two-component multiple schedule: a random-interval 30 s schedule of pellet presentation and a conjoint random-interval 30 s schedule of pellet presentation, random-interval 2 s schedule of timeout 10 s presentation. Once responding had stabilized subjects were injected intraperitoneally with vehicle, chlordiazepoxide (1-30 mg/kg), buspirone (0.1-4.2 mg/kg) or cocaine (1-30 mg/kg), 15 min before the start of the experimental session. Before drug administration, punished response rates were less than 30% of unpunished response rates for four of the six subjects, and 60% and 75% for the other two. Low doses of chlordiazepoxide (1 and 3 mg/kg) increased punished responding (range 25-300%), and slightly increased unpunished response rates (by 25% in all but one subject, whose rates increased by 75%). The higher doses of chlordiazepoxide (10-30 mg/kg) dose-dependently decreased response rates in both components. The lower doses of buspirone (0.1 and 0.3 mg/kg) either did not affect, or decreased response rates in both components of the schedule; the higher doses produced dose-dependent decreases. Low doses of cocaine (1, 3 and 5.6 mg/kg) did not affect response rates in either component of the multiple schedule, whereas higher doses produced a dose-dependent decrease in response rates, except for one subject whose punished response rates increased substantially. The behavioral effects of chlordiazepoxide and buspirone observed in the present experiment were similar to those observed in experiments in which response rates were suppressed by shock presentation.  相似文献   

8.
A total of 20 female Long-Evans rats trained to press a retractable lever for food in a discrete trials situation were subsequently punished for responding. After suppression of responding, response-independent shocks were presented, with intensity increased on successive daily sessions. Shock induced responding, and number of responses, increased and response latencies decreased with increasing shock intensity. Control Ss initially given uncorrelated lever-food presentations responded significantly less to response-independent shock, and their responding was not systematically related to shock intensity. Results are consistent with the view that shock induces or disinhibits prepotent responses and inconsistent with the view that, to be effective in suppressing behavior, punishment must induce responses incompatible with the punished response. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
Trained male Wistar albino rats (10 experimental and 9 control Ss) to barpress for food reinforcement in a 2-bar cyclic response chain situation. Responding on 1 bar led also to a punishment (footshock) on either an intermittent or constant schedule. Both punishment schedules led to increased responding on the nonpunished bar and to initial response suppression followed by recovery on the punished bar. For Ss on the intermittent schedule, the response increase on the nonpunished bar was seen only after a punishment on the other bar. Similar effects were found for transfer time between the 2 bars. The effects of punishment on response to both bars were more pronounced for the intermittent punishment groups. Results are discussed in terms of the motivational constructs of A. Amsel and of R. K. Banks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
The effects of d-amphetamine, pentobarbital, chlorpromazine and promazine on responding under schedules of electric shock postponement were studied in pigeons. Responding was maintained by three different response-shock intervals (10, 20 and 60 seconds). Low doses (0.3-3 mg/kg) of d-amphetamine increased response rates without decreasing shock rates under all three response-shock intervals. The highest dose (10 mg/kg) of d-amphetamine increased the shock rates under all response-shock intervals and decreased the high response rate under the 10-second response-shock interval but did not decrease the lower rates of responding under the 20- and 60-second response-shock intervals. Pentobarbital decreased the high rate of responding maintained under the 10-second response-shock interval at lower dose (10 mg/kg) than the lower rates of under the 20- and 60-second response-shock intervals. The high dose (17.5 mg/kg) of pentobarbital decreased responding and the low doses (1-3 mg/kg) had no effect under all three response-shock intervals. Chlorpromazine (3-100 mg/kg) did not affect the average rate of responding under all response-shock intervals and only slightly increased shock rates under the 20- and 60-second response-shock intervals. Promazine (3-30 mg/kg) increased the rates of responding and decreased shock rates under all three response-shock intervals. Analysis of the temporal patterns of responding within the response-shock interval showed that d-amphetamine tended to induce the animals to respond earlier than they normally would in the response-shock interval while otherwise maintaining the temporal pattern of responding, pentobarbital decreased the probability of responses late in the response-shock interval, and chlorpromazine and promazine increased the probability of responses in the middle of the response-shock interval, producing a lessening of the temporal patterning of responding within the response-shock interval.  相似文献   

11.
Conducted 2 experiments in which 144 and 54 goldfish, respectively, were trained in a shuttlebox with light as CS and brief shock as UCS. Performance was measured in terms of "initial response" to the CS (at least 1 crossing of the hurdle on any trial) and-where the CS was not terminated by the initial response-in terms of "multiple response" to the CS (more than 1 crossing on any trial). The level of initial responding was as high in classically conditioned Ss (shocked on every trial) as in avoidance Ss, whether or not the CS was terminated by response, but lower in control Ss, yoked with the avoidance Ss, and lower also in punished Ss (shocked only if they responded). Multiple responding was negligible in avoidance Ss, but common in classically conditioned and in punished Ss. Results can be accounted for in purely Pavlovian terms, no reference to instrumental learning being required. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
Hypothesized that facilitation of avoidance performance of rats with septal lesions occurs only in tasks that punish responses having the same topography as the avoidance response, such as intertrial responses, or tasks that have aversive consequences for making the avoidance response, such as a brightly illuminated safe compartment. 28 male Sprague-Dawley rats (Exp I) were trained in 2 shuttle box tasks, and 24 (Exp II) were trained in 2 running-wheel avoidance tasks under conditions of punishment or nonpunishment of intertrial responses. Ss with septal lesions performed better than controls in both the shuttle box and the wheel tasks when intertrial responses were punished. When intertrial responding was not punished, experimental and control groups did not differ in avoidance performance. Avoidance performances of punished and unpunished Ss with septal lesions did not differ from each other or from unpunished controls in either wheel or shuttle box tasks. Results are discussed in the context of the species-specific defense reaction (SSDR) avoidance theory of R. C. Bolles (see record 1970-04813-001). It is suggested that septal lesions interfere with the suppression of ineffective SSDRs. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
In rats trained in an operant fixed-interval-30-s schedule of food reward (FI-30s), acute exposure to contingent footshock resulted in a response suppression that was released by diazepam (DZP; 4 mg/kg ip) but not by buspirone (0.25 or 0.50 mg/kg ip). Compared with baseline, hippocampal and cortical extracellular levels of serotonin (5-HText) did not change, regardless of operant period (punished or nonpunished) and drug. In contrast, in the striatum, an increase of 5-HText levels (535%) occurred during the punished period, counteracted by DZP. This effect was observed only in rats that were low responders during both nonpunished and punished periods, that is, those that exerted an efficacious control over responding. Uncontrollable shocks or exposure to an unfamiliar open field did not modify striatal 5-HText. Together, these results suggest that an acute activation of 5-HT neurons afferent to the striatum allows the rats to efficiently block responses that are negatively reinforced. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
In investigating the effect of reward upon the acquisition and extinction of avoidance response, a word association task was presented to 90 Ss for 8 conditioning and 12 extinction trials. During conditioning, associations to preselected words were punished on Trial 1 and whenever S repeated them. There were 3 acquisition groups: 1 received the above training, the 2nd also received reward for substitute associations, and the 3rd obtained reward during the 2nd ? of acquisition only. Each acquisiton group was divided into 2 extinction subgroups: 1 received neither reward nor punishment while the 2nd was rewarded for avoiding. Results indicated that reward hastened acquisition and delayed extinction of avoidance responses, thus confirming hypotheses regarding the concept of secondary gain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
AMPA receptor antagonists disrupt avoidance responding, but their day-to-day effect on this behavior has not been elucidated. This study compared the multisession effect of the AMPA/kainate receptor antagonist CNQX with that of the typical antipsychotic haloperidol on the expression of avoidance responding. Rats (N = 199) were trained to move to safety on presentation of a tone in one-way active conditioned avoidance and were tested across 5 sessions. Intracerebroventricular (icv) injection of CNQX (20-min injection-test interval) produced a dose-dependent, immediate block of avoidance responding, compared with the extinction-like decline of avoidance responding produced by haloperidol (intraperitoneal [ip], 60-min injection-test interval; icv, 60 but not 20-min injection-test interval). Previous exposure to CNQX significantly reduced its efficacy, illustrating that its effects may not be specific to the conditioned safety-related stimuli that control responding in conditioned avoidance, as proposed for antidopaminergic compounds. The new multisession profile of disrupted avoidance responding illustrated by CNQX suggests different roles for glutamatergic and dopaminergic neurotransmission in conditioned avoidance responding. Results are consistent with a role for AMPA receptors in maintaining the expression of learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
Examined whether age-related differences in suppression occur when a learned response is punished. 8 groups of weanling and adult male Holtzman rats (N = 96) received active-avoidance training and subsequent punishment for that response. Following active avoidance, Ss were assigned to a regular extinction group or to 1 of 3 punishment-delay (0-, 2-, or 10-sec.) groups, which received shock in the goal box. Although weanlings and adults were equivalent in active-avoidance acquisition, under the immediate punishment condition immature Ss required significantly more trials to learn passive avoidance. A delay-of-punishment gradient was obtained in adults but not in weanlings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Administered either high or low punishments in the form of candy removal to 24 1st and 2nd graders ostensibly for their performance on a keypressing task. Punishment was actually presented according to a preprogrammed schedule independent of the S's responding. Interspersed with these trials, stories were told about children who resisted temptations, and the Ss assigned rewards or punishments to these characters. Following high punishment, the Ss punished the characters less frequently and intensely than after low punishment. Since modeling and reward-deservedness explanations are untenable in this study, the results are interpreted in terms of image improvement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
Previous research has shown that the rate of punished lever pressing of monkeys is typically decreased by cocaine administration. However, cocaine increases punished responding in monkeys with a history of responding maintained by the postponement of shock presentation. This raises the question of whether other behavioral effects of cocaine differ following a history of postponing shock. The present experiment examined whether a history of postponing shock alters the discriminative stimulus effects of cocaine. Three squirrel monkeys were trained to discriminate cocaine (0.56 mg/kg, intramuscular) from saline. Presses on the left lever produced food following saline injections whereas presses on the right lever were reinforced following administration of cocaine. Occasional test sessions were conducted in which cocaine (0.1-0.56 mg/kg), midazolam (0.03-0.56 mg/kg) or pentobarbital (0.3-5.6 mg/kg) was injected prior to the session and responding on either lever was reinforced. Discrimination training was discontinued during a second experimental phase in which responding was maintained by shock postponement. Pulling a chain postponed mild shocks for 25 s, whereas shocks occurred every 5 s in the absence of responding. Next, the drug discrimination dose-response curves were redetermined. The dose-response curves for all drugs before and after the shock postponement history were similar. This outcome suggests that the influence of a history of shock postponement is specific to punished responding.  相似文献   

19.
Conducted 6 experiments with male Holtzman rats. A single noncontingent footshock was found to facilitate subsequent one-way and shuttle avoidance if the CS in preshock and avoidance training was the same. If the to-be-established instrumental response was punished during preshock, or if Ss were required to run toward the CS paired with shock during pretraining, the facilitative effects of preshock were eliminated. Facilitation by a single preshock was not enhanced if shock was escapable, regardless of the CSs, task, or whether escape was immediate or delayed. If Ss received 10 one-way escape trials, the beneficial effects of preshock on one-way and shuttle avoidance were enhanced. In contrast, shuttle-escape training produced no such beneficial effects on avoidance performance. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
In Exp. I, 80 male albino rats 10, 15, 20, 30, or 100 days old received a brief inescapable shock contingent upon making a step-off response. Step-off latencies increased for all age groups, but rate of learning was significantly faster in older Ss. Learning appeared to be based primarily upon punishment effects rather than general emotionality, since yoked Ss shocked after being placed directly on the grids did not acquire the avoidance response. Exp. II with 120 Ss employed 3 training conditions with independent groups 12, 15, 18, or 21 days old. The step-off response resulted in shock that was either: (a) escapable; (b) inescapable, 1-sec duration; or (c) inescapable, yoked duration. Younger Ss were again significantly inferior to more mature Ss. Escapable shock improved acquisition at 2 age levels, but the effect appeared to be more related to shock duration than to the response contingency. It is suggested that the requirement of withholding a punished response may represent a category of learning that is especially sensitive to maturational changes. (French summary) (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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