Concurrent schedules: Spatial separation of response alternatives

Four pigeons were exposed to independent concurrent variable-interval 20-second variable-interval 60-second schedules of reinforcement. A transparent partition was inserted midway between the two response keys. The length of the partition was systematically manipulated. Increasing partition length produced a decrease in changeover rate in Experiment 1. Over-matching was observed with a partition length of 20 centimeters. In Experiment 2 a four-second limited hold was added to the schedules. Increasing partition length produced a decrease in changeover rate that exceeded the decrease observed in Experiment 1. This manipulation produced nearly exclusive choice of the variable-interval 20-second component. The present results, together with results obtained in related research, suggest that deviation from matching is a function of procedural variables that determine the consequences of a changeover response.     

Duration-reduction of avoidance sessions as negative reinforcement

Five rats were exposed to a shock-postponement procedure in which responses on each of two levers initially had equivalent effects. After an initial training sequence that ensured at least some responding on each lever, an additional consequence was made conjointly operative on the previously less-preferred lever for each animal. Each response on this lever continued to postpone shock, but also reduced the session duration by one minute. The conjoint contingencies were operative until, through session-shortening responses and the passage of time, the session was scheduled to end in two minutes; during the final two minutes the session-shortening contingency was disabled while the shock-postponement contingency continued to be operative on both levers. When responding shifted to a predominance on the session-shortening lever, the conjoint contingency was shifted to the other lever; for four of the five rats this reversal was followed by two additional reversals. Two of the rats' responding showed clear, strong, and unambiguous sensitivity to the session-shortening contingency. The responding of two others was also systematically controlled by that contingency, but the effects were less clearcut. The fifth animal showed an initial shift when session-shortening was introduced, but its subsequent behavior proved insensitive to reversals of procedure. The results clearly indicate a sensitivity of behavior to events on a time scale quite distinct from that of immediate consequences. They also support an interpretation of avoidance sessions, considered in their entirety, as events whose contingent relationship to behavior can affect that behavior—even in the absence of stimuli that delineate those relationships. Finally, these results support an interpretation of aversively based conditioning within a broader context, analogous to the “open versus closed economy” interpretation of appetitively controlled behavior.     

Effect of lingual vibrotactile stimulation on the averaged cortical evoked response

This study was designed to determine the feasibility of using lingual vibrotactile stimulation to elicit an averaged evoked response and to investigate the effects of two supra-threshold intensity levels of lingual vibrotactile stimulation on the electro-cortical activity of the brain. The evoked responses were analyzed according to the amplitude of N1-P2 (in microvolts). Analysis indicates that the tongue can successfully be used as a stimulus site in the elicitation of an evoked response. The amplitudes of the evoked response elicited by 2 micrometers sensation level and 5 micrometers sensation level on the tongue are essentially the same. The relative difference between these levels is not sufficient to produce significant differences in the amplitudes of their respective evoked responses.     

Complex form of instrumental behavior of dogs

A complex form of higher nervous activity, conditional reflex transswitching or switching, was elaborated in four dogs under conditions of unrestrained movements, freedom of reinforcement choice (food or water), place of reinforcement determined by situation factors as well as independent switching on of conditional stimuli. It was shown that motivated goal-directed behavior of the animals was determined by activation of forward and backward connections. The chains of instrumental conditioned reflexes forming in the final analysis the complex behavior are developed according to the “trialand-error” principle. In the instrumental conditioned reflexes there are two constantly coexisting types of mutually complementing conditioned connections of the signal with reinforcement—direct and indirect. In experiments with unrestrained conditions of animals and independent regulation of the experiment, one of the frequently encountered physiological mechanisms of generalization appears to be efferent and afferent generalization.     

The MMPI'S of left- and right-handed subjects

Previous research has suggested that left-handedness relates to delinquency and violence. In an effort to pinpoint the nature of this apparent relationship, we compared the MMPIs of 72 left- and 687 right-handed men 60 yr. old or less on an alcohol treatment ward. No significant differences appeared. The results are compared to earlier research and hypotheses for further research are suggested.     

Clinical, electroencephalographic and computer tomographic studies of children with West and Lennox-Gastaut syndrome

The results of clinical, electroencephalographic and repeated computed tomographic examination of 14 children suffering from epileptic seizures in connection with the West and Lennox-Gastaud syndrome are analyzed and compared. Computed tomography yields little information regarding the etiology of such forms of epilepsy. Distinct clinical and electroencephalographic findings were accompanied by normal computed tomographic results in a large proportion of the cases. To avoid misinterpretation of computed tomographic findings and consequent prognostic errors in these epileptic cases it is necessary to take possible side effects of ACTH and corticosteroid treatment into account. At the climax of hormone treatment computed tomography revealed imposing changes in the form of generalized atrophy in 10 of the 14 children examined. These receded completely upon termination of hormone treatment.     

The sociodynamogram--a contribution to the objectivization of group process

Two simple sociometric techniques for practical use are described which are derived from the data given in the sociogram. Compared with the conventional sociogram, the group rank score we use everyday therapy has the advantage that it can be published. It permits members of the group to better identify the social situations which cause specific psychic impulses. The sociogram is reserved for the therapist. In our opinion the sociodynamogram has certain advantages over both methods because it provides an insight into spheres which are inaccessible in the sociogram and group rank score.