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D F Hake

Publications and source records attributed to D F Hake.

9 recordsLinked to original sources

Some relations between classically conditioned aggression and conditioned suppression in squirrel monkeys.

During three experiments with squirrel monkeys, stimulus and shock pairings were given in the presence of a bite tube. Experiments 1 and 2 used a conditioned-suppression procedure in which bar pressing was reinforced with food. A transparent shield prevented biting of the bar. When the stimulus was paired with shock, bar pressing decreased (conditioned suppression) and tube biting increased during the stimulus (classically conditioned aggression). When the bite tube was removed on alternate sessions in Experiment 2, there was more suppression when the tube was present, thus suggesting that biting competed with bar pressing. However, this simple competing-response interpretation was complicated by the findings of Experiment 3 where, with naive monkeys, bar pressing was never reinforced with food, yet bar pressing was induced during the stimulus and was highest when the bite tube was absent. The fact that stimulus-induced bar pressing developed inciated that bar pressing in conditioned-suppression procedures, suppressed or not, may be maintained by two types of control--the food reinforcer and induced CS control. The higher rate of induced bar pressing during the stimulus with the bite tube absent confounds a simple competing response interpretation of conditioned suppression. It suggests that shock-induced responses during conditioned suppression could be both contributing to and competing with responding maintained by food, with the net effect depending on specific but ill-defined features of the situation.

Aggression

Analysis of the control exerted by a complex cooperation procedure.

The study examined the effects of the availability of a non-cooperative response on cooperative responding when cooperation did not have to result in an equal distribution of work or reinforcers. Also, an attempt was made to determine if the cooperative responding was under the control of the cooperation procedure. Pairs of institutionalized retardates were tested in full view of each other. For each subject, reinforcers (money) were contingent upon responses on each of two panels: (1) a matching panel for working matching-to-sample problems, and (2) a sample panel for producing the sample stimulus. The matching panels of the two subjects were 6 m apart, but a subject's sample panel could be placed at different distances from his matching panel. For each subject, either his own or his partner's sample panel could be nearest his matching panel such that less walking was required to reach one sample panel than the other. Subjects could work either individually, by producing their own sample stimulus, or cooperatively, by producing the sample stimulus for their partner. Subjects selected whichever solution involved the least amount of walking. The importance of testing for control by the cooperation procedure was indicated by the findings that cooperative-like responses were not always under the control of the cooperation procedure.

Adult

Characteristics and response-displacement effects of shock-generated responding during negative reinforcement procedures: pre-shock responding and post-shock aggressive responding.

Bar-pressing (Experiment I) or key-pressing (Experiments II and III) responses of monkeys were reinforced according to a fixed-interval schedule of negative reinforcement: the first response after a fixed interval of time terminated regularly spaced shocks for a fixed time designated as the reinforcement period. During extinction, shocks continued during the reinforcement period. That there were two types of responding generated by shock alone was indicated by (1) the level of responding maintained during extinction relative to conditions without shock, (2) the stability of two between-shock response patterns across reinforcement and extinction conditions, and (3) the development of these two between-shock patterns without a history of reinforcement. Subjects developed either a pre-shock or a post-shock response pattern when only the bar was available. However, when both a bite tube, an operandum requiring an aggressive topography, and a recessed key, an operandum that did not require an aggressive topography, were provided, the post-shock pattern was observed in tube biting and the pre-shock pattern was observed in key pressing. Removal of the bite tube produced post-shock key responding similar to that observed when only the bar was available. The displacement of post-shock, aggression-motivated responding confirmed the confounding effect of shock-generated responding in negative reinforcement procedures, and suggests that the use of concurrent response alternatives would reduce such confounding.

Aggression

A classification and review of cooperation procedures.

The definition of cooperation allows many procedural variations, as revealed by examination of the cooperation literature which includes procedures differing so greatly that it is surprising that all of them are considered under the same topic. This paper attempts to provide a framework for organizing that literature by (1) indicating some procedural dimensions along which cooperation procedures can be classified, (2) classifying and reviewing briefly the research at the extremes of these procedural dimensions, and (3) indicating the behavioral effects that are necessary to demonstrate control by the various cooperation procedures.

Cooperative Behavior

An extinction-induced increase in an aggressive response with humans.

Nine subjects, 14 to 18 yr old, pulled a knob on a schedule of monetary reinforcement. Concurrently, they escaped or avoided periodic presentations of a tone by pressing a button that required 1.5 lb (6.67 N) of force or by punching a padded cushion that required 20 lb (88.96 N) of force. The punching response was designated as an aggressive response because the force of this response together with its topography was comparable to responses of humans that deface objects and produce escape or counter aggression from other humans. It was found that button pressing was the preferred concurrent avoidance response and there were few punches. However, when the monetary reinforcer was discontinued (extinction) punching increased for seven of the nine subjects, but there was no consistent change in the rate of button pressing. When the punching response was replaced by another non-preferred but non-aggressive response, neither this response nor button pressing increased during extinction. Hence, the increase in punching during extinction cannot be attributed solely to the fact that it was a concurrent response or a non-preferred response.

Adolescent

Actual versus potential shock in making shock situations function as negative reinforcers.

The relative importance of potential and actual shocks in making shock situations function as negative reinforcers was studied. Shocks were scheduled to occur at the same rate during two stimuli. During one, squirrel monkeys could avoid the shocks; during the other, they were unavoidable. For the two stimuli the potential rate of shocks was the same, but the actual rate was lower during avoidance because of avoidance responding. Fixed-ratio responding was maintained by the change from unavoidable shock to avoidance, indicating that the change was reinforcing when it resulted in a reduction in actual shock rate with no reduction in potential shock rate. Further increases in the rate of potential shock during avoidance had little effect upon the fixed-ratio responding until the rate was increased to the point that the actual shock rate during avoidance was comparable with that during unavoidable shock. At that point, the fixed-ratio response rate decreased nearly to zero. These findings show that actual shocks are more important than potential shocks in determining whether or not a shock situation will function as a negative reinforcer; this explains why the change from unavoidable shock to avoidable shock is reinforcing.

Animals

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

Social facilitation of responses during a stimulus paired with electric shock.

Key-pecking responses of a pigeon were maintained by a variable-interval schedule of food reinforcement. The responses were suppressed during the occasional presentation of a warning stimulus paired with electric shock. The presence of a second pigeon emitting the same response for food reinforcement reduced the suppression that otherwise occurred during the warning stimulus when the second pigeon was absent. These results reveal that the social facilitation phenomenon can be used to restore behavior that is suppressed by a conditioned aversive stimulus.

Animals