Discriminated Avoidance Response Research Articles

Patients' awareness of sexual effects of psychotropic medication

Effects of oral antipsychotic drugs, 12 phenothiazines, 3 thioxanthenes, 5 butyrophenones and 8 other derivatives on Sidman and discriminated avoidance responses in rats were investigated and compared to their clinical doses routinely used PO. Almost all drugs except sulpride and clozapine suppressed the avoidance responses with a dose-dependent decrease in the response rate (lever-pressing) and increase in the shock rate in the Sidman avoidance performance or a decrease in both the response and avoidance rates in the discriminated one. Sulpiride (80–640 mg/kg) produced no marked change in the avoidance responses. Clozapine (2.5–10 mg/kg) increased the shock rate or decreased the avoidance rate without eliciting any change in the response rate. The avoidance-suppressing activities of the antipsychotic drugs were well correlated with their clinical daily doses. However, the avoidance-suppressing effects of carpipramine, clocapramine, thiothixene and sulpride were relatively less potent, while that of clotiapine was more potent than in the clinical activities. The potencies of the avoidance-suppressing effects of each drug on the Sidman and the discriminated avoidance responses were almost identical except for triflupromazine, pimozide, thioridazine, spiclomazine and propericiazine. The former two drugs suppressed the Sidman avoidance response more than the discriminated avoidance response. However, the latter three drugs suppressed the discriminated avoidance response more markedly than the Sidman avoidance response. The present results suggest that the avoidance response in rats is applicable in evaluating the clinical efficacies of antipsychotic drugs.

Impairment of cingulothalamic learning-related neuronal coding in rabbits exposed to cocaine in utero: general and sex-specific effects.

Neuronal activity was recorded in the cingulate cortex and the limbic thalamus in Dutch-belted rabbits (Oryctolagus cuniculus) exposed to cocaine (8 mg/kg/day i.v.) or saline in utero during acquisition and reversal learning of a discriminative avoidance response. Anterior cingulate cortical excitatory training-induced activity (TIA) was attenuated in cocaine-exposed female rabbits during acquisition and reversal learning, but only during reversal learning in male rabbits. Posterior cingulate cortical excitatory TIA was lessened in cocaine-exposed rabbits during acquisition, whereas discrimination between the positive and negative cues was enhanced. Neuronal firing was attenuated in the anterior ventral thalamus in cocaine-exposed rabbits during acquisition and reversal learning. Behavioral learning was normal in cocaine-exposed rabbits. Other data suggest that rabbits exposed to cocaine in utero exhibit a learning deficit when trained with nonsalient cues.

Cerebellar interpositus nucleus lesions disrupt classical nictitating membrane conditioning but not discriminative avoidance learning in rabbits

Cerebellar interpositus nucleus lesions were given to 14 rabbits trained in two behavioral paradigms; discriminative avoidance conditioning of locomotor behavior and classical nictitating membrane conditioning. Bilateral lesions that prevented acquisition of the classically conditioned response on both the left and right side failed to affect the acquisition or performance of the conditioned discriminative avoidance response. The results are discussed in terms of differences in neural substrates that apparently subserve the two forms of learning.

Studies on the mechanism(s) for the ‘atypical’ neuroleptic activity of remoxipride

Effects of oral antipsychotic drugs, 12 phenothiazines, 3 thioxanthenes, 5 butyrophenones and 8 other derivatives on Sidman and discriminated avoidance responses in rats were investigated and compared to their clinical doses routinely used PO. Almost all drugs except sulpride and clozapine suppressed the avoidance responses with a dose-dependent decrease in the response rate (lever-pressing) and increase in the shock rate in the Sidman avoidance performance or a decrease in both the response and avoidance rates in the discriminated one. Sulpiride (80–640 mg/kg) produced no marked change in the avoidance responses. Clozapine (2.5–10 mg/kg) increased the shock rate or decreased the avoidance rate without eliciting any change in the response rate. The avoidance-suppressing activities of the antipsychotic drugs were well correlated with their clinical daily doses. However, the avoidance-suppressing effects of carpipramine, clocapramine, thiothixene and sulpride were relatively less potent, while that of clotiapine was more potent than in the clinical activities. The potencies of the avoidance-suppressing effects of each drug on the Sidman and the discriminated avoidance responses were almost identical except for triflupromazine, pimozide, thioridazine, spiclomazine and propericiazine. The former two drugs suppressed the Sidman avoidance response more than the discriminated avoidance response. However, the latter three drugs suppressed the discriminated avoidance response more markedly than the Sidman avoidance response. The present results suggest that the avoidance response in rats is applicable in evaluating the clinical efficacies of antipsychotic drugs.

Shuttlebox avoidance programs for the 6502

Two programs were written in assembly language for the 6502 microprocessor to control a wide variety of learning procedures for a shuttlebox. Both programs can control two shuttleboxes simultaneously. The first program includes routines for the traditional discrete-trial avoidance procedures, including operant level (CS only), avoidance, punishment, and Pavlovian conditioning (US presentation independent of the response). Session parameters (number of trials, durations of the CS, US, and IT!) may be set over a wide range of values, and response-contingent CS termination is an option. Session-identification data, the latency of the first response on each trial, and the total number of intertrial responses are both printed and stored in memory. Latencies, rather than just the occurrence of a response, are measured. Bolles (1979) argued that the failure of the response latencies to change over time is evidence that the animal is showing a species-specific defense reaction rather than avoidance learning. The second program controls the linear presentation procedure described by Zerbolio (1981). This method was developed with the thought that the traditional shuttlebox avoidance procedures do not provide unambiguous evidence for the acquisition of a discriminated avoidance response in goldfish. In the typical avoidance learning experiment, an increase in response rate is taken as evidence for learning. Goldfish present a problem in that they are known to increase their rate of responding not only in the situation in which there is response-contingent shockomission, but also under a large variety of procedures, including no US presentation (Steiner, 1971) and Pavlovian procedures (Woodard & Bitterman, 1971). Zerbolio's procedure provides a parallel to the response requirements of a Y maze. In the shuttlebox, each trial begins with a trial-start stimulus. If the fish responds, by shuttling to the other end of the tank, either an S+ or an Sstimulus is presented on a randomized basis. Ifthe fish makes additional responses on this trial, the S+ and Sstimuli alternate. At the end of the trial, the fish receives the US if the trial-start or S stimuli are in effect. To avoid the

Correlation between antiavoidance activities of antipsychotic drugs in rats and daily clinical doses

Effects of oral antipsychotic drugs, 12 phenothiazines, 3 thioxanthenes, 5 butyrophenones and 8 other derivatives on Sidman and discriminated avoidance responses in rats were investigated and compared to their clinical doses routinely used PO. Almost all drugs except sulpride and clozapine suppressed the avoidance responses with a dose-dependent decrease in the response rate (lever-pressing) and increase in the shock rate in the Sidman avoidance performance or a decrease in both the response and avoidance rates in the discriminated one. Sulpiride (80–640 mg/kg) produced no marked change in the avoidance responses. Clozapine (2.5–10 mg/kg) increased the shock rate or decreased the avoidance rate without eliciting any change in the response rate. The avoidance-suppressing activities of the antipsychotic drugs were well correlated with their clinical daily doses. However, the avoidance-suppressing effects of carpipramine, clocapramine, thiothixene and sulpride were relatively less potent, while that of clotiapine was more potent than in the clinical activities. The potencies of the avoidance-suppressing effects of each drug on the Sidman and the discriminated avoidance responses were almost identical except for triflupromazine, pimozide, thioridazine, spiclomazine and propericiazine. The former two drugs suppressed the Sidman avoidance response more than the discriminated avoidance response. However, the latter three drugs suppressed the discriminated avoidance response more markedly than the Sidman avoidance response. The present results suggest that the avoidance response in rats is applicable in evaluating the clinical efficacies of antipsychotic drugs.

Instrumental avoidance acquisition by goldfish in a Y-maze using explicit and response-contingent cues

In two experiments, goldfish learned a discriminated avoidance response in a Y-maze. When alternative response alleys were simultaneously and differentially cued at trial onset, the goldfish learned to swim to the alley associated with US omission. When alternative response alleys were not differentially cued at trial onset and the US association cue was contingent upon an initial response to one of the alternatives, goldfish learned, following the initial response, to stay in the initially chosen alley when the response-contingent cue indicated US omission, but to leave the initially chosen alley and swim to the alternative alley when the response-contingent cue indicated US pairing.

45) - Correlation between suppressing effects of antipsychotic drugs on Sidman or discriminated avoidance response in rats and their clinical doses.

45) - Correlation between suppressing effects of antipsychotic drugs on Sidman or discriminated avoidance response in rats and their clinical doses.

Effects of psychotropic drugs on avoidance response in rats: Role of baseline performances

Effects of d-amphetamine, chlorpromazine and diazepam on the discriminated avoidance response (intertrial interval = 25 sec; warning duration = 5 sec) in rats were studied with reference to levels of the behavioral baseline. After the administration of d-amphetamine 0.25–2.0 mg/kg SC, the avoidance and response rates increased in all cases dose-dependently. The individual changes of avoidance rates were more marked in the poor performers (initial avoidance rate: 0–33%) with higher baseline response rates than in those with lower response rates. Chlorpromazine 0.5–2.0 mg/kg SC suppressed the avoidance performances in all cases in proportion ith the doses. More marked changes were observed in the good performers (68–100%) than in the poor performers regardless of the baseline response rates. After administration of diazepam 0.5–4.0 mg/kg SC, the response rates decreased in almost all cases, while the avoidance rates varied depending on their baseline levels. Diazepam increased the avoidance rates of the poor performers, but conversely decreased the rates in the good performers in proportion with the doses. Moreover, the improvement of the avoidance rates was more marked in the poor performers with higher baseline response rates than in those with lower rates. The present results suggest that the behavioral effects of psychotropic drugs are a function of the avoidance baseline levels.

Observational Learning of a Discriminative Shuttlebox Avoidance by Rats

The study of observational learning of discriminative avoidance response in shuttlebox has methodological advantages over the usual appetitive responses. Three groups of 10 Wistar rats each received avoidance training after observation of a trained model, after observation of a naive model, after adaptation to procedure and no model. The first group performed better than the naive-model group both for frequency and latency of responses. The hypothesis that this learning occurs through observation of the model's behavior explains these results. However, observing the behavior to be learned does not facilitate acquisition of the avoidance response compared with rats learning after adaptation and no model.

Effects of fluphenazine enanthate and fluphenazine decanoate on discriminated avoidance response and water drinking behavior in rats.

Effects of the long-acting neuroleptic drugs fluphenazine enanthate (FE) and fluphenazine decanoate (FD) on discriminated avoidance response and daily patterns of water drinking behavior in rats were studied. Single doses of FE or FD (2, 4, and 8 mg/kg) were given IM to rats showing a response rate (lever pressing) of 2.5–4.0/min and an avoidance rate of 85–95% under the discriminated avoidance schedule (intertrial interval 25 s, warning duration 5 s). The inhibitory effect of the drugs attained a peak after 1–3 days then gradually decreased. However, an apparent dose-dependent inhibition of the avoidance response lasted for 15–25 and 35–100 days with FE and FD, respectively. Control rats given sesame oil alone showed a regular 24-h drinking pattern, synchronized with the 12 h light-dark cycle, with a high rate of drinking in the dark period (about 90% of the daily total). Eating behavior was similar to the drinking behavior. Drinking was markedly inhibited by a single dose of FE or FD (8 mg/kg IM) for the first 24 h, but returned to the predrug level within a week. There was little drug effect on the 24 h drinking pattern after the first 24 h. The inhibitory effect of FE on drinking behavior tended to be stronger than that of FD. The present results demonstrate that both FE and FD exert specific strong and prolonged inhibitory effects on the conditioned avoidance response without making substantial changes on fundamental behaviors such as drinking and eating.

Study of accumulation of fluphenazine enanthate and fluphenazine decanoate, long-acting neuroleptic drugs, after repeated administrations by means of their inhibitory effects on the discriminated avoidance response in rats.

Accumulation of fluphenazine enanthate (FE) and fluphenazine decanoate (FD), long-acting neuroleptic durgs, after repeated administration was investigated by means of their inhibitory effect on the discriminated avoidance response in rats. When FE 0.13 mg/kg, and FD 0.13 and 0.25 mg/kg were given i.m. once a day, the inhibitory effect enhanced progressively until about the 10th and 30th day in the cases of FE and FD, respectively. The maximum levels of suppression were maintained during the later medication periods. After the withdrawal of the drugs, the avoidance response recovered gradually and returned to each pre-drugged level on about the 20th, 30th and 100th day in the cases of FE 0.13, FD 0.13 and FD 0.25 mg/kg/day, respectively. When 1 and 2 mg/kg of each FE and FD were given i.m. once a week for 8 weeks, a progressive enhancement of the avoidance-suppressing effect was observed until the 3rd and 6th injection in the cases of FE and FD, respectively, and thereafter almost the same weekly variation pattern of the avoidance response was repeated. The present results suggest that the enhancement of the avoidance-suppressing effect after repeated administration of FE and FD is resulted from the accumulation of these drugs, and that the absorption and metabo1ism of the drugs in the body reach a steady state after 10-15 days in the former and 30-35 days in the latter, independently of the dose and administration intervals.

Effects of Appetitive Pretraining of a Relevant Operant Response on the Subsequent Acquisition of a Discriminated Avoidance Response in the Rat

Rats typically have great difficulty acquiring a discriminated operant bar avoidance. But, the majority of animals learn to bar-press to terminate shock (escape response). The problem of generating efficient bar-press behavior in a relatively convenient period of time and in a satisfactorily high percentage of subjects has been a problem for experimenters working with the Sidman avoidance reinforcement schedule. In a recent review of the literature, it is concluded that the rats fail to master the bar-press conditioned operant response because it is so unlike any of the animal's naturally occurring “species-specific defense reactions (SSDRs)”.The present study asked whether an appetitive pretraining procedure designed to produce high levels of avoidance reponding early in training could have sustained beneficial effects on the performance of a discriminated flapper-push avoidance task. If a flapper-pushing response was positively reinforced and established before the avoidance test, it seems logical that the subsequent avoidance acquisition task would be facilitated.During an 8-day pretraining period 16 animals (Experimental) were trained to push a flapper for food reward. Eight animals (Control) received the same number of food pellets and were exposed to the same apparatus as the Experimental animals. However, the manipulandum was inoperative during pretraining for Control animals. On completion of the appetitive pretraining period, all animals received the signaled Sidman avoidance conditioning treatment (a daily 1 hr. conditioning session for 6 consecutive days). For example, if the animal permitted 30 sec. to elapse without a flapper-push, a warning stimulus (1250 Hz., 84 db. tone, 5 sec. duration) appeared and remained until terminated by a response. Each response in the absence of tone postponed both tone and a brief shock (shock-shock interval 3 sec., shock duration 0.4 sec., shock intensity 1 ma. a. c.) for 30 sec.Fig. 1 shows the number of flapper-push responses during the appetitive pretraining period for both Experimental and Control groups. The Experimental group made more responses as compared to the Control group. The present data show that appetitive pretraining to flapper-push for food improves the later acquisition of flapper-push avoidance (Fig. 2 and 4). It is likely that the Experimental group was responding for food during avoidance sessions, although these animals did not receive food reinforcement for response emitted. The significant differences in the number of interstimulus responses (Fig. 3) and total flapperpushing response (Fig. 4) between the Experimental and Control groups indicate that the appetitive pretraining procedure generates a high response rate. Figs. 2 and 5 indicates that the Control group performed quite poorly during the first three avoidance conditioning days. It is conceivable that the repeated shocks during these initial conditioning days firmly establish SSDRs in the Control subjects.The greater frequency of avoidance responses in the Experimental group was associated with a greater frequency of non-warning flapper responses, indicating that improved avoidance was a direct result of a general increase in flapperpushing. Therefore, increasing the habit strength by pretraining for food, which should not interference with the fear conditioning, seems to be critical.

On the independence of stimulus evocation of fear and fear evocation of responses

Dogs in an experimental group were first trained in a shuttlebox on a free-operant avoidance response; then a second, discriminative avoidance response was trained in a second apparatus to a tone. Following criterion, the second avoidance response was “extinguished” through unsignaled. response-independent US presentations. Finally, the tone was presented in the shuttlebox as a test for residual fear. The tone produced as much facilitation of the free-operant avoidance responding as it did in two control groups; one control had not had the second avoidance response extinguished, while the other had received only Pavlovian conditioning in the second apparatus. Thus, the elimination of a discriminative avoidance response to a CS does not impair the CS's ability to control a second independent avoidance response. This result reflects and confirms the separability and independence of the CS-fear and fearavoidance response links hypothesized by two-process theories.

Behavioral differences between killer and nonkiller rats

Killer and nonkiller rats were compared on the following behavioral measures: reactivity to handling, open-field activity divided into the number of squares traversed and rearing, defecation in the open field, and learning and retention of a discriminated avoidance response. In contrast to certain other reports, killer rats differed from nonkillers only in the number of rearings in the open field. On the basis of this study, killers do not appear to be more reactive than nonkillers.

SAFETY SIGNALS AND THE ACQUISITION AND EXTINCTION OF LEVER‐PRESS DISCRIMINATED AVOIDANCE IN RATS

Rats learned a discriminated avoidance response more rapidly when a safety signal occurred following an escape or avoidance response. Two extinction procodures were used: complete omission of shock or delivery of an unavoidable shock at the end of the warning period. Under the latter procedure, avoidance‐extinction responding was initially higher but subsequently declined to the same level as under the omission procedure. Under each extinction procedure animals were divided into two subgroups: safety signal and no‐safety signal. The safety signal did not significantly effect avoidance responses in extinction per se, but it did result in fewer extra responses during the inter‐trial and safety periods following an avoidance—extinction response. With no‐safety signal there was an increase over extinction sessions in the numbers of such extra responses, especially in the shock delivery subgroup.

Self-punishment for responding by monkeys during extinction of discriminated avoidance: effects of previous stimulus change reinforcement.

Two groups of rhesus monkeys acquired a discriminated avoidance response (lever-pressing) under different training procedures. One group was trained using a conventional escape-avoidance procedure for 6 training sessions. The other group received one escape-avoidance session following 5 training sessions with stimulus-change reinforcement in which lever pressing momentarily terminated the light-tone combination later used as CS during avoidance training. Experience with stimulus change reinforcement facilitated acquisition of avoidance responding. Both groups showed self-punishment during extinction and did not differ significantly on this dimension.

The effect of magnesium pemoline, tricyanoaminopropene, and d-amphetamine on discriminated avoidance performance in rats as a function of age

The effects of magnesium pemoline, tricyanoaminopropene, and d-amphetamine on the acquisition of a discriminated avoidance response were compared in 30-, 50-, and 100-day-old naive rats. The rats were placed in an automated shuttlebox immediately after drug treatment. The number of avoidance responses in a series of 100 trials was measured. Ten days after the initial acquisition session, the rats were retrained on the same task. The 30-day group was inferior to the 50- and 100-day groups in the training session, but no differences occurred in retraining. The drug-treated groups showed improved performance in the initial training session but were not different from the controls in the retraining session. No Drug by Age interaction was significant.

A reinterpretation of extinction in discriminated avoidance

Accepting escape from the warning signal and/or avoidance of shock as the source of reinforcement for the discriminated avoidance response, extinction is redefined in terms of withholding these effects following the response. The effects of warning intervals of 5, 10, and 20 sec on the redefined extinction procedure were reported, and rapid reliable decreases in responding were found for all Ss, similar to positive reinforcement studies.

Long-term discriminated avoidance in two species of fish

Three bass and two sunfish learned a discriminated avoidance response in a shuttle box. During 3300 farther trials, all Ss showed excellent performance with no decrement, a minimal “warm-up” effect, and stereotyped response topography.