Shock-induced aggression as a function of prior experience with avoidance, fighting, or unavoidable shock

Rats were trained in shock-induced aggression, free operant avoidance, or were presented with unavoidable shocks. Fighting in response to shock was subsequently measured by intermatching individual animals that had received the three training procedures. The fighting probabilities of animals with histories of avoidance and dominant animals with histories of fighting were higher than the fighting probabilities of non-dominant fighting rats or rats with a history of unavoidable shocks. Animals with higher fighting probabilities disrupted avoidance baselines more than animals with lower fighting probabilities. Control experiments suggested that fighting decrements produced by administration of prior grid-shock were due to the acquisition of behaviors incompatible with aggression.     

Some effects of punishment shock intensity upon discriminative responding

Three pigeons received visual discrimination training under both multiple variable-ratio extinction and variable-interval extinction schedules. All birds developed nearly perfect discrimination. When punishment for every tenth response during food reinforcement was presented, responding decreased as shock intensity increased. At the same time, responding during extinction, which was not punished, increased at intermediate punishment intensities, but returned to low levels under severe punishment. A second procedure, in which punishment and no-punishment sessions alternated unsystematically, was employed with two of the birds. The results under this procedure essentially replicated the data obtained as punishment shock intensity increased gradually.     

A method for the objective study of tool-using behavior

Key pecking for food was shaped in four crows within a conventional operant-conditioning test chamber. When pecking stabilized, a metal screen with openings 2.5 cm high by 1.0 cm wide, was placed over the response key, so that the crow could still see but could no longer peck the key. At the same time, several dozen wooden matchsticks, which could be used to operate the key, were placed in the test chamber. The crows made no use of these during 50 to 75 hr of exposure to this condition. Subsequently, the behavior of two crows was shaped so that they approached the matchsticks, picked one up in their beaks, approached the response key with the matchstick in their beak, and finally operated the response key by poking the matchstick through the screen. This shaping procedure was ineffective with the two other crows. However, these birds were successfully trained through positional fading of the tool. This involved suspending a metal rod from the ceiling so that it hung directly in front of the response key, and the crow had only to peck it to operate the key. Then, the rod was gradually lowered by lengthening its tether until it eventually rested on the floor of the test chamber. The principal advantage of this methodology is the automatic recording of the terminal (tool-using) behavior under study.     

Is the reaction time-movement time relationship 'essentially zero'?

It was hypothesized that, if RM-MT correlations are "essentially zero," then the magnitude of that correlation should not be subject to variation due to the manipulation of various experimental variables. In this experiment, Ss were tested with either RT-MT together or done separately. Results indicated significant relationships for 18 males but not for 18 females. The "essentially zero" position was discussed as being procedurally specific.     

Increasing engagement in a home for the elderly by providing an indoor gardening activity.

This project investigated the effect of a new recreational activity on the generally low level of engagement of residents in two lounges of a Local Authority home for the elderly physically frail. Indoor gardening sessions open to all residents were held on one afternoon each week in the dining room of the home. In the setting-up phase a researcher ran the gardening sessions, developed a set of written instructions on how to organize the activity and used these. plus performance feedback, to train a volunteer to run the sessions. The experimental phase evaluated the residents' level of engagement during the weekly gardening sessions and on another afternoon each week when there were no planned recreational activities. The results show that indoor gardening was very successful in producing sustained activity by the residents attending and that engagement of the residents was significantly higher on gardening than on non-gardening days.     

Can we measure out a life in coffee spoons?

Public policy decisions in medicine and other fields necessitate careful weighing of choices and consequences. Cost-benefit analyses have been offered as one way to facilitate such decisions. In "Quantifying the value of human life," L. Eugene Arnold asserts that mathematical models such as his offer greater clarity in making public policy decisions than is possible with the "intuitive" or "emotional" approach. In our opinion, problems associated with this quantitative analysis demonstrate a need for caution in applying such mathematical models to public policy decisions....