Temporal control in fixed-interval schedules

The peak procedure was used to study temporal control in pigeons exposed to seven fixed-interval schedules ranging from 7.5 to 480 s. The focus was on behavior in individual intervals. Quantitative properties of temporal control depended on whether the aspect of behavior considered was initial pause duration, the point of maximum acceleration in responding, the point of maximum deceleration, the point at which responding stopped, or several different statistical derivations of a point of maximum responding. Each aspect produced different conclusions about the nature of temporal control, and none conformed to what was known previously about the way ongoing responding was controlled by time under conditions of differential reinforcement. Existing theory does not explain why Weber's law so rarely fit the results or why each type of behavior seemed unique. These data fit with others suggesting that principles of temporal control may depend on the role played by the particular aspect of behavior in particular situations.     

ON THE VALUE OF KNOWING ONE'S LIKES AND DISLIKES:

Abstract— On the basis of laboratory research indicating that accessible altitudes ease decision making we hypothesized that freshmen who enter college knowing their likes and dislikes regarding academically relevant issues may experience better health in this new life setting To test this hypothesis, we conducted a prospective study in which students completed self-report inventories of negative life events and mental and physical health at two points in time. The accessibility of attitudes toward academically relevant issues was assessed in the initial session Regression analyses revealed three-way interactions between attitude accessibility, stress (as indexed by the number of negative life events), and initial health status when initial health, the generally positive relation between stress and illness was buffered by the possession of accessible attitudes For students with relatively poor initial health, recovery Has generally greater among those experiencing less stress, especially as attitude accessibility increased.     

EFFECTS OF CHOOSING ACADEMIC ASSIGNMENTS ON A STUDENT WITH ATTENTION DEFICIT HYPERACTIVITY DISORDER

The effects of choosing academic assignments on the undesirable behaviors manifested by a second-grade student with attention deficit hyperactivity disorder were analyzed. This study extended Dunlap et al.'s (1994) research on choice making as a form of antecedent control. A reversal design showed that undesirable behaviors decreased when the student was given a choice of academic assignments.     

Attrition During the Pretreatment Stage of a Drug-Free Therapeutic Community

In the treatment of dnig abusers a continuing problem is the high attrition rate. This study focussed on m New South Wales treatment facility, Odyssey House, and aimed to discover some of the variables associated with attrition. A simple of people admitted to the program was divided into two groups, those who left within 30 days and those who did not. Most of the client variables were nonsignificant. The most significant predictor of attrition was the client's status IS a new admission or as a readmission; re-admissions were more likely to stay than newly admitted people. Also significant were the length of previous treatment, suicide attempt history, clients' perceptions of the toughness of the program and the predictions made by the admission team. The study indicated a need for further investigation of program and environmental variables and of interactions among these and client variables.     

The prefrontal-thalamic axis and classical conditioning.

Using the New Zealand albino rabbit as an animal model, it has been determined that the medial prefrontal cortex is intimately involved in, and may be necessary for, acquisition of classically conditioned bradycardia. The interconnected nuclei of the medial thalamus, most notably the mediodorsal nucleus, conversely appear to be associated with the development of the tachycardia that accompanies classical conditioning of the eyeblink and nictitating membrane response. Neuroanatomical, electrophysiological, brain stimulation, and lesion data are reviewed, which support the conclusion that the prefrontal-thalamic axis is intimately involved in acquisition of classically conditioned visceral changes.     

The relationship of personality to antisocial and neurotic behaviours as observed by teachers

Eight hundred and eight children in normal schools between the ages of 7 and 16 yr were rated on Rutter's Teachers' Rating Scale, and completed the EPQ giving Psychoticism (P), Extraversion (E), Neuroticism (N) and Lie (L). The children also reported on their own misbehaviour and social attitudes. Children exhibiting Antisocial behaviours were markedly high on P; also scoring low on L, and reporting non-conforming behaviour and attitudes. Children showing Neurotic behaviours did not have particularly distinctive personality scores, but were rather extraverted and conforming (high L). There was no relationship between Neuroticism as a disorder and Neuroticism as a personality trait. It is suggested that the P scale might usefully assist in the detection of antisocially disturbed children or in the selection of ‘high risk’ groups.     

Concomitant Pavlovian conditioning of heart rate and leg flexion responses in the rat

Pavlovian conditioning was studied in male Fischer 344 rats using tones as the conditioned stimulus (CS) and footshock as the unconditioned stimulus (UCS). Different groups of animals received (a) contiguous CS-UCS pairings with a 0.5 sec CS, (b) contiguous CS-UCS pairings with a 4.0 sec CS, or (c) a random sequence of noncontiguous tones and shocks using either a 0.5 sec or a 4.0 sec CS. Heart rate (HR) and leg flexion (LF) responses were recorded. Leg flexion conditioning occurred only in the 0.5 sec contiguous group. Decelerative HR CRs occurred only in the 4.0 sec contiguous group. Accelerative HR changes occurred in the other two groups but were significantly greater in the 0.5 sec contiguous group. These results are similar to but not identical to those obtained during eyeblink or nictitating membrane conditioning in rabbits, and suggest that the topography of the Pavlovian HR CR is dependent on the simultaneous occurrence of other classically conditioned responses.