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Biomedical subjects

N H Azrin

Publications and source records attributed to N H Azrin.

At least 73 records · Page 4Linked to original sources
PubMed1969

Positive conditioned suppression: conditioned suppression using positive reinforcers as the unconditioned stimuli.

Research has revealed the phenomenon of conditioned suppression in which the rate of responding is reduced during a stimulus that is paired with noncontingent shock. The present study replicated this procedure, but used noncontingent positive reinforcers instead of the aversive shock. The lever-pressing responses of rats were reinforced with food or water. While the rats were responding, a stimulus was occasionally presented and paired with the delivery of a noncontingent positive reinforcer, which was either food, water, or brain stimulation for different rats. The result was a reduction in the rate of responding during the conditioned stimulus. This finding shows that conditioned suppression occurs during a signal for reinforcing as well as aversive stimuli.

Journal Article↗
PubMed1969

A response-spacing effect: an absence of responding during response-feedback stimuli.

In most studies of operant reinforcement a response-feedback stimulus is used which is so brief that the nature of the responding during it is virtually undetectable. The present study investigated the nature of this responding by lengthening an initially brief feedback stimulus. The key-pecking responses of pigeons were maintained by a variable-interval schedule of food reinforcement. Each response produced a brief stimulus light in addition to the usual auditory response feedback. When the duration of the feedback stimulus light was gradually increased, it was found to control a nearly zero rate of responding. The result was a paced, metronomic-like performance in which the pigeon made a single response, paused until the stimulus terminated, and then responded again. As a result, the overall response rate was greatly reduced; the mean interresponse time approximated the stimulus duration. A plausible interpretation is that brief feedback stimuli acquire control over responding because they coincide with few responses and few reinforcers. These findings show that in addition to their known functions as conditioned-reinforcing stimuli and discriminative stimuli, response-feedback stimuli also exert direct stimulus control: responding is reduced during the feedback stimulus itself.

Journal Article↗
PubMed1968

Reinforcer sampling: a technique for increasing the behavior of mental patients.

Mental hospital patients in a motivating ward environment were using the available reinforcers less than was desired. A procedure for increasing the frequency of using reinforcers was developed: all patients were required to engage in the reinforcing event each time it was available but the duration of this required participation was limited so that the event was merely sampled. The effect of this required sampling was experimentally evaluated for three different reinforcers: going for a walk, watching a movie, and attending a music session. More patients used each of the three reinforcers and to a greater extent when the sampling procedure was used. Participation was increased even for those patients who had already been using the reinforcers, demonstrating that the technique did more than provide simple familiarization. Some familiarization was involved since the participation was slightly increased even after the sampling procedure was discontinued. The technique appears to be especially applicable when reinforcers are being delivered infrequently.

Journal Article↗
PubMed1968

Behavioral engineering: the reduction of smoking behavior by a conditioning apparatus and procedure.

Recent findings from animal conditioning studies have revealed methods of reducing responses to a very low level with a minimum of aversive by-products. These findings were incorporated into the design of a cigarette case that automatically locked itself for a period of time after a cigarette was removed from it. The next cigarette could be taken at the end of the interval, which was signalled by distinctive stimuli. Five heavy smokers were allowed to become accustomed to using the case. Then, the duration for which the case was locked was gradually increased over a period of weeks to about 1 hr. Smoking gradually decreased to the target level of about one-half of a package of cigarettes per day. Control procedures showed that specific features of the apparatus were responsible for the reduction of smoking. The results indicated that this apparatus was sufficiently effective, convenient, and acceptable to smokers to constitute a practical procedure for reducing smoking to the level considered medically safe. The procedure may also have potential for reducing other habit-forming or addictive behaviors.

Journal Article↗
PubMed1968

Attack produced by intermittent reinforcement of a concurrent operant response.

Squirrel monkeys pressed a lever to produce food on several fixed-ratio schedules; they could also bite a rubber hose. Biting attack occurred during the postreinforcement pause and in early portions of the ratio response run. Also, biting attacks increased after transitions to higher values of the fixed-ratio requirement and in extinction. The results show that extinction-induced aggression effects occur in primates.

Aggression↗
PubMed1968

Biting attack by rats in response to aversive shock.

Paired rats are known to behave aggressively when given painful electric shocks. The present study developed a procedure whereby individual rats given shocks might bite an inanimate target object. Unavoidable shock was delivered to the rat while it was restrained in a position close to, and facing a target object. Biting of the target was recorded automatically. Shock caused the rat to bite metal, wood, or rubber targets. Biting was most frequent immediately after shock and decreased as a direct function of time since the shock. Almost every shock produced biting and the behavior continued as long as the shocks were delivered. Biting ceased within and between sessions when shocks were discontinued. These results show how the pain-aggression relation can be studied objectively with rats.

Aggression↗
PubMed1968

Effects of shock intensity and duration on the frequency of biting attack by squirrel monkeys.

Squirrel monkeys were periodically exposed to brief tail-shocks in the presence of a rubber tube connected to a pneumatic switch. Biting attack upon this tube was found to be a decreasing function of time since shock delivery and a direct function of shock intensity and duration. These results parallel findings in investigations employing more "naturalistic" social situations, indicating that attack against the inanimate and animate environment is a direct function of the intensity of an aversive stimulus. The results also demonstrate that frequency of biting attack as a datum is sensitive to several experimental manipulations.

Aggression↗
PubMed1967

Attack, avoidance, and escape reactions to aversive shock.

Aversive stimuli are known to produce the behaviors of both escape and attack. The interaction between these two basic reactions was studied with rats and monkeys using many shock-escape and shock-avoidance procedures. All procedures produced attack if a target was present, the attacks occurring shortly after shock delivery. The number of attacks during escape or avoidance was a direct function of the number and duration of shocks received. Consequently, any aspect of the procedure that produced many shocks also produced many attacks such as initial acquisition, extinction, or an increase of the response requirement for escape. The escape tendency acquired prepotency over the tendency to attack since successful escape eliminated attack behavior. The attack tendency retarded escape behavior only during acquisition when the preoccupation with attack precluded the opportunity to learn the escape response. This mutual interference of escape and attack was eliminated when the attack and avoidance tendencies were combined by using biting attack as the shock-avoidance response. The result was unusually rapid conditioning of the biting-attack response. These interactions indicate that both the attack and escape tendency should be considered whenever aversive stimulation is delivered.

Aggression↗
PubMed1967

Temporal patterns of sexual behavior in rabbits as determined by an automatic recording technique.

Sexual behavior between rabbits was automatically recorded by means of electrodes attached externally to the unrestrained animals. Current flowed only when the animals came into physical contact; the duration and amplitude of the current flow provided a means of automatic differentiation between sexual and other types of physical contact. Various temporal aspects of sexual behavior were revealed: (1) copulation was preceded by a series of thrusts that occurred at a constant frequency of 13 to 14 thrusts per sec; (2) the duration of a copulation was about 1.5 sec and could be as brief as 0.3 sec; (3) copulation was much more likely during the hours between dusk and dawn despite constant illumination; (4) copulations occurred in groups or "runs" characterized by many copulations within a few hours; (5) each run began with a high rate of copulation that often decreased over time; (6) between runs, several hours or days passed with little or no sexual activity; and (7) a run of copulations was noted at the end of every 16- to 20-day period (which corresponds to the known period of pseudopregnancy in rabbits) whether or not other runs occurred within this period.

Animals↗
PubMed1967

A rat chamber and electrode procedure for avoidance conditioning.

A method was developed for studying the reactions of rats to aversive shock. The distinctive features were the design of the chamber and a method of restraint that allowed the use of surface electrodes to deliver the shock. Advantages of this method were: (1) accurate specification of the shock actually received by the rat; (2) elimination of all unauthorized escape or avoidance reactions; (3) elimination of the shock scramblers and floor grids required with foot-shock; and, (4) rapid acquisition of performance under various avoidance procedures and various frequencies of shock delivery.

Animals↗
PubMed1967

Conditioning of the aggressive behavior of pigeons by a fixed-interval schedule of reinforcement.

Operant reinforcement of aggression was studied in food-deprived pigeons by delivering food for attacks against a target pigeon. The food was delivered according to a fixed-interval schedule and attack behavior was recorded automatically. Attack could be conditioned and extinguished, and the proportion of time spent in attack was a direct function of the frequency of reinforcement of the attack. The fixed-interval schedule produced an increasing rate of attack during the interval between food reinforcements. This positive curvature was an inverse function of the duration of the interval. The findings revealed that the duration and temporal patterning of the complex social behavior of attack can be influenced in a substantial and predictable manner by the schedule and frequency of operant reinforcement.

Aggression↗
PubMed1967

The effects of punishment intensity on squirrel monkeys.

Responses of squirrel monkeys were maintained by a variable-interval schedule of food reinforcement. Concurrently, punishment consisting of a brief electric shock followed each response. As has been found for pigeons and rats, punishment did not produce extreme, all-or-none reactions. By gradually increasing the punishment intensity it was possible to produce response rates intermediate to no suppression and complete suppression. Similarly, the moment-to-moment response rate was free of extreme fluctuations. A "warm-up" effect occurred in which the punished responses were especially suppressed during the initial part of a session. The pre-punishment performance was negatively accelerated within a session, and punishment reduced the degree of negative acceleration. When punishment was discontinued, responding recovered immediately except when suppression had been complete or prolonged. When the punishment intensity was decreased gradually, more suppression resulted at a given intensity than when intensity was increased gradually. This suggests a "behavioral inertia" effect wherein behavior at a new punishment intensity is biased toward the behavior at the previous value. A corollary generalization is that the larger the change in intensity, the less the behavior at the new value will be biased toward the behavior at the previous value.

Journal Article↗
PubMed1966

Extinction-induced aggression.

Pigeons were conditioned to peck a response key under a procedure that alternated periods of food reinforcement with periods of extinction. The pigeons attacked a nearby pigeon at the onset of extinction. Some also attacked a stuffed model of a pigeon. The duration of attack was an inverse function of the time since the last food reinforcement and a direct function of the number of reinforcements. The pigeons attacked after the last food delivery whether or not the conditioned pecking response was required and whether or not the extinction period was signaled. The food had to be eaten; the mere sight and sound of food being delivered did not produce attack. Prior satiation reduced attack. The phenomenon was not attributable to a past history of competition between pigeons since socially deprived pigeons also attacked. Superstitious reinforcement of attack was not found to be a factor. The results indicated that the transition from food reinforcement to extinction was an aversive event that produced aggression.

Journal Article↗
PubMed1966

Punishment as a discriminative stimulus and conditioned reinforcer with humans.

Mental hospital patients were reinforced for responding in a two-response operant situation. When a noise was used to punish one of the responses, all subjects shifted to the unpunished one. When the noise was then paired with positive reinforcement, the subjects responded to produce the noise. Also, a novel response was reinforced by noise in the absence of other reinforcers. This study with humans extends the findings of previous studies with animals in revealing how a punishing stimulus can acquire discriminative or conditioned reinforcing properties.

Conditioning, Operant↗
PubMed1965

The measurement and reinforcement of behavior of psychotics.

An attempt was made to strengthen behaviors of psychotics by applying operant reinforcement principles in a mental hospital ward. The behaviors studied were necessary and/or useful for the patient to function in the hospital environment. Reinforcement consisted of the opportunity to engage in activities that had a high level of occurrence when freely allowed. Tokens were used as conditioned reinforcers to bridge the delay between behavior and reinforcement. Emphasis was placed on objective definition and quantification of the responses and reinforcers and upon programming and recording procedures. Standardizing the objective criteria permitted ward attendants to administer the program. The procedures were found to be effective in maintaining the desired adaptive behaviors for as long as the procedures were in effect. In a series of six experiments, reinforced behaviors were considerably reduced when the reinforcement procedure was discontinued; the adaptive behaviors increased immediately when the reinforcement procedure was re-introduced.

Adult↗
PubMedDate not supplied

Identification of neuropsychological subtypes in a sample of delinquent adolescents.

Although research has long recognized a relationship between neurological dysfunction and delinquency, the nature of this relationship is unclear. Based on the theory that there may be clusters of delinquents with different types of neurological dysfunction which contribute to the delinquency in different ways, the present research attempted to identify these subtypes using neuropsychological testing. Seventy-seven such adolescents were administered the full Luria-Nebraska Neuropsychological Battery-III (LNNB-III) and a battery of assessments measuring behavioral functioning and substance use. A Hierarchical Cluster Analysis yielded four identifiable neuropsychological clusters: Verbal/Left-Hemispheric Deficits, Subcortical-Frontal Deficits, Mild-Verbal Deficits, and Normals. The distinctiveness of these subtypes was confirmed by univariate analyses. Results further indicated that the number of LNNB scales that were in the abnormal range differed per subtype, with each subtype differing significantly from one another. These neuropsychological subtypes were found to be associated with specific psychological and behavioral problems.

Adolescent↗