Visible persistence following a brief increment in stimulus luminance

In previous studies, it has been demonstrated that visible persistence--the period for which the perceived duration of a stimulus exceeds its physical duration--can be extended by briefly incrementing the luminance of the stimulus immediately prior to offset. Using a two-component pattern integration task, we show that this effect is not an artifact of change in the total luminous flux within the stimulus. Visible persistence was unaffected by overall luminance of the stimulus. It was also time-locked to the luminance increment. Visible persistence is seen to result from a process that is initiated by stimulus onset and that can be either wholly or partially reinitiated by the onset of the luminance increment. The duration of this process (which determines the duration of stimulus visibility) can be modified in a graded fashion by stimulus events that occur after its initiation. We outline a single-process inhibitory feedback model of the persistence mechanism that accounts for the present findings.     

Personality factors in dysphoria: A psychometric refinement of beck's Sociotropy-Autonomy Scale

The Sociotropy-Autonomy Scale (SAS) was developed as a means of assessing two cognitive-personality constructs postulated as vulnerability factors in depression (Beck, 1983). While studies have confirmed the validity of the SAS Sociotropy Scale, the construct validity of the Autonomy Scale has not been well supported. The present study was conducted to improve on the measurement of autonomy by generating additional items which were added to the original questionnaire. This 93-item SAS was administered to 485 undergraduates along with the Beck Depression Inventory, Beck Anxiety Inventory, PRF Affiliation and Autonomy Scales, Positive and Negative Emotionality Measures, and Marlowe-Crowne Social Desirability Scale. Four factors labeled Sociotropy, Solitude/Interpersonal Insensitivity, Independence, and Individualistic Achievement emerged from a principal-factor analysis of the SAS item pool. Hierarchical multiple regression analyses indicated that positive emotionality and solitude/interpersonal insensitivity were specifically related to dysphoria, while negative emotionality and sociotropy had significant associations with both anxious and depressed mood states.This research was supported by University of New Brunswick Research Grant 22–51 awarded to the first author.     

Responding to indirect speech acts

Indirect speech acts, like the request Do you know the time?, have both a literal meaning, here “I ask you whether you know the time,” and an indirect meaning “I request you to tell me the time.” In this paper I outline a model of how listeners understand such speech acts and plan responses to them. The main proposals are these. The literal meaning of indirect speech acts can be intended to be taken seriously (along with the indirect meaning) or merely pro forma. In the first case listeners are expected to respond to both meanings, as in Yes, I do—it's six, but in the second case only to the indirect meaning, as in It's six. There are at least six sources of information listeners use in judging whether the literal meaning was intended seriously or pro forma, as well as whether there was intended to be any indirect meaning. These proposals were supported in five experiments in which ordinary requests for information were made by telephone of 950 local merchants.     

Effects of genetic vestibular defects on behavior related to spatial orientation and emotionality.

A large battery of behavioral tests was administered to normal mice and to mice with varying degrees of otoconial agenesis due to genes affecting vestibular development. Many significant differences were found, but a factor analysis revealed that the variance on the 11 best tests could be accounted for in terms of two underlying variables. Factor I, the more important of the two, was associated with activity, habituation, and spontaneous alternation. Factor II appeared to represent a fear of new stimuli or situations. In both cases factor scores were highly related to the degree of otoconial deficiency. One subgroup of mice with severe otoconial agenesis displayed hyperactivity and a total absence of either habituation or spontaneous alternation. In these animals, brain and body development were stunted, and the reactions to amphetamine and physostigmine were opposite to those seen in normal mice. The results support the idea that the static organs contribute importantly to spatial orientation and suggest that early-onset vestibular defects can result in profound alterations of emotionality.     

Peer tutoring among elementary students: educational benefits to the tutor

To determine whether tutoring might be academically beneficial to the tutor, this study investigated the acquisition of spelling words by three elementary students in a peer tutoring program. The experimental design allowed a simultaneous comparison of each child's gain in performance on comparable word lists on which the child tutored another child, was tutored by another child, or neither gave nor received tutoring. The children's spelling improved nearly an equivalent amount on those words on which they tutored another child as on the words on which they were tutored; no such change was noted on the words on which they neither gave nor received tutoring. These findings, that peer tutoring is profitable for the tutor as well as the tutee, provide a basis for recommending peer tutoring as one method of individualizing education.     

The Cost-Reward Model of Helping Behavior: A Nonconfirmation1

A field experiment was designed to test several predictions derived from the Piliavin and Piliavin cost-reward model of helping behavior. Female and male subjects' reported intent to help a hemophiliac in a nearby hospital was unrelated to the costs for helping, the costs for not helping, and the order in which the subjects received the costs' manipulations. The obtained rates of helping were also unrelated to whether or not subjects reported having donated previously. Failure to obtain the predicted results is discussed.     

A comparison of the key-peck and treadle-press operants in the pigeon: differential-reinforcement-of-low-rate schedule of reinforcement

Key pecking and treadle pressing in pigeons were compared under concurrent (key-treadle) and single-operant differential-reinforcement-of-low-rate schedules of food reinforcement ranging from 5 to 60 sec (concurrent procedure) or 5 to 120 sec (single-operant procedure). Under both procedures, the two operants followed the same general law: decreasing response rate and reinforcement rate and increasing number of responses per reinforcement as a function of increasing schedule interval. High correlations were found between key pecking and treadle pressing for the measures of response rate, reinforcement rate, and responses per reinforcement. Regression equations allowed the prediction of treadle pressing from key pecking. More bursting occurred in responding to the key, and key pecking showed a more precise temporal discrimination than treadle pressing. A test for sequential dependencies between key and treadle responses showed significant dependencies not only under the concurrent procedure but also in data created artificially by merging key and treadle sequences from different pigeons under the concurrent procedure and from the same pigeon under the single-operant procedure. It seems likely that the sequential dependencies found were due to the independent action of the schedule on each operant and that behavioral dependencies did not occur with the concurrent training procedure. The key-peck operant does not appear to have any special qualities that preclude its use in discovering general laws of behavior, at least under the differential-reinforcement-of-low-rate schedule. The usefulness of the key peck in other situations requires direct experimental study.     

Manipulation of response-contingent unconditioned-stimulus intensity in human eyelid conditioning: A two-phase model analysis

Four groups of human subjects were given 360 classical eyeblink conditioning trials. All groups received the same UCS (unconditioned stimulus) intensity on[Formula: see text] (nonconditioned response) trials but differed in the intensity presented on CR trials. Response probability increased as a positive function of UCS intensity on CR trials. Phase 1 of the two-phase model was longer when no UCS was presented on CR trials, but did not differ in duration among the remaining three groups. Most subjects could be described with a single operator in Phase 2, the operator limit increasing as a positive function of CR-contingent UCS intensity. For subjects requiring different operator limits on CR and[Formula: see text] trials, the latter was lower with high CR-trial intensities but higher with low CR-trialintensities. The results were interpreted to be more consistent with drive theory than with "law-of-effect" or two-factor theories.     

How to keep romance in your marriage

Pastoral Psychology -