Stimulus control depends on the subjective value of the outcome

Stimuli that provide information about likely future reinforcers tend to shift behavior, provided a reliable relation between the stimulus and the reinforcer can be discriminated. Stimuli that are apparently more reliable exert greater control over behavior. We asked how the subjective value (measured in terms of preference) of reinforcers associated with stimuli influences stimulus control. Five pigeons worked on a concurrent chains procedure in which half of all trials ended in a smaller reinforcer sooner, and the other half in a larger reinforcer later. In Signaled trials, the color and flash duration on the keys in the initial link signaled the outcome of the trial. In Conflicting probe trials, the color and the flash duration signaled conflicting information about the outcome of the trial. Choice in Signaled trials shifted toward the signaled outcome, but was never exclusive. In Conflicting probe trials, control was divided idiosyncratically between the 2 stimulus dimensions, but still favored the outcome with the higher subjective value. Thus, stimulus control depends not only on the perceived reliability of stimuli, but also on the subjective value of the outcome.     

A path analysis of factors associated with distress among first-degree female relatives of women with breast cancer diagnosis.

Patterns and predictors of psychological distress in first-degree female relatives (N = 624) of newly diagnosed breast cancer patients were explored. First-degree female relatives who were high monitors reported greater cancer-specific and general distress than did low monitors. Greater optimism was associated with lower cancer-specific distress. Optimism's effect on general distress was moderated by women's level of monitoring. Greater optimism was associated with lower general distress for both high and low monitors, but the effect was stronger for high monitors than for low monitors. Avoidance and engaged coping were associated with higher distress. A close relationship with the cancer patient was related to higher cancer-specific distress but lower general distress. Further understanding of the process of adjustment in these women awaits longitudinal study.     

Persistent symptoms among survivors of Hodgkin's disease: an explanatory model based on classical conditioning.

Persistent symptoms of nausea, distress, and vomiting triggered by reminders of cancer treatment were examined among 273 Hodgkin's disease survivors, 1 to 20 years posttreatment. Prevalence rates were high for distress and nausea but low for vomiting. Retrospective report of anticipatory symptoms during treatment was the strongest predictor of persistent symptoms, suggesting that treatment-induced symptoms are less likely to persist if conditioning does not occur initially. Time since treatment was also a significant predictor, with patients more recently treated more likely to experience persistent symptoms. Thus, an explanatory model based on classical conditioning theory successfully predicted presence of persistent symptoms. Symptoms also were associated with ongoing psychological distress, suggesting that quality of life is diminished among survivors with persistent symptoms. Recommendations for prevention and treatment of symptoms are discussed.     

Reliability and validity of the Multiple Affect Adjective Check List - Revised

A recent factor analysis of the Multiple Affect Adjective Check List (MAACL) changed the Anxiety, Depression, and Hostility scales from bipolar to unipolar scales and added two new scales: Positive Affect and Sensation Seeking. Internal reliability of the MAACL-R scales, computed for normal and patient samples, was adequate for state and trait forms except for Sensation Seeking. Test-retest reliability in college students was higher for the trait form with retest intervals of from 2 to 8 weeks than for the state form with retest intervals of from 2 to 5 days. The pattern of correlations among self-, peer, and counselor ratings and the MAACL-R scales for normal and patient samples indicates improved discriminant validity and equally good convergent validity as the old scales. The use of standard scores that are indexed to the number of items checked reduced scale intercorrelations by controlling the acquiescence set.The financial support of the Weldon Springs Endowment Fund, University of Missouri at Kansas City, toward the completion of this research project is gratefully acknowledged.     

Prompt comprehension in UNIX command production

We hypothesize that a cognitive analysis based on the construction-integration theory of comprehension (Kintsch, 1988) can predict what is difficult about generating complex composite commands in the UNIX operating system. We provide empirical support for assumptions of the Doane, Kintsch, and Polson (1989, 1990) construction-integration model for generating complex commands in UNIX. We asked users whose UNIX experience varied to produce complex UNIX commands, and then provided help prompts whenever the commands that they produced were erroneous. The help prompts were designed to assist subjects with respect to both the knowledge and the memory processes that our UNIX modeling efforts have suggested are lacking in less expert users. It appears that experts respond to different prompts than do novices. Expert performance is helped by the presentation of abstract information, whereas novice and intermediate performance is modified by presentation of concrete information. Second, while presentation of specific prompts helps less expert subjects, they do not provide sufficient information to obtain correct performance. Our analyses suggest that information about the ordering of commands is required to help the less expert with both knowledge and memory load problems in a manner consistent with skill acquisition theories.     

Beliefs m Realistic and Unrealistic Control: Assessment and Implications

ABSTRACT Scales were constructed to measure perceived control over controllable events (realistic control) and perceived control over uncontrollable events (unrealistic control). Internal reliability, test-retest reliability, and discriminant validity of both scales were adequate. Study 1 measured perceived personal control over hassles that judges rated on general controllability. For hassles very high in controllability, perceived personal control was related to belief in realistic control but not to belief in unrealistic control; for hassles very low in controllability, perceived personal control was related to belief in unrealistic control but not to belief in realistic control. Study 2 showed that participants high in unrealistic control belief (but not those high in realistic control belief) persevered more on a task that was in part uncontrollable. Study 3 showed that the combination of low realistic control belief and high unrealistic control belief predicted poorer future health, particularly for participants who have reported the experience of many negative events and/or hassles. The conditions under which unrealistic control results in maladaptive outcomes are discussed.     

Behavioral competition in a case of Rett syndrome

Major behavioral features of Rett syndrome are the loss of instrumental reaching and grasping and the presentation of some variant of hand-hand or hand-mouth stereotypy. As part of an experimental home intervention program, a 3-year-old girl with Rett syndrome was exposed to four types of contingency games designed to elicit instrumental reaching, kicking, vocalization, and eye movement, respectively. Parent and subject performance were videorecorded on seven occasions over the initial 2-month period. Evaluation of these records provided evidence of contingency learning in all but the vocalization games. Stereotypic hand clasping was examined in relation to the performance of instrumental behavior (reaching, kicking, looking). Coincidental (short-term mutual inhibition arising by chance co-occurrence), associative (short-term mutual inhibition arising by having elicitor in common), and foundational (long-term mutual inhibition arising by having neural network in common) forms of specific behavioral competition were defined and examined. Evidence for coincidental and foundational competition was found in the relation between reaching and hand clasping. Implications for the support of functional hand use are discussed.     

A multiple-risk interaction model: Effects of temperament and divorce on psychiatric disorders in children

Effects of family status on the trajectory of problematic temperament-adjustment at 1 to 10 years of age and associated psychiatric disturbance 8 years later were examined in an epidemiological sample of 648 children. After adjusting for predivorce temperament-adjustment and background factors, logistic regression yielded independent effects of single custodial mother (SCM) family status for increased risk of disruptive and anxiety disorders, and of stepfamily status for increased risk of disruptive disorders. Increased risk of psychiatric disorders was more pervasive for SCM family boys versus intact family boys than for SCM family girls versus intact family girls, however only significantly more so for depression. No significant sex interaction was observed for stepfamily status. When girls and boys were treated independently, patterns of family status and outcomes of internalizing disorders varied. In stepfamilies, an elevated risk of depression and anxiety disorders was observed in girls but not boys, whereas in SCM families an elevated risk of depression was observed in boys but not girls. Within each family status group there was support for an altered risk of later psychiatric disorders given specific problematic predivorce temperament-adjustment characteristics. Implications for future research and treatment are discussed.The research described was supported by grants from the National Institute of Mental Health and by the W. T. Grant Foundation.     

The conjunction fallacy: A test of averaging hypotheses

The conjunction fallacy, in which individuals report that the conjunction of two events is more rather than less likely to occur than one of the events alone, is a robust phenomenon. We assessed the possibility that an analysis in terms of functional measurement methodology might be consistent with occurrence of the fallacy. A 3 × 3 design in which we varied the judged likelihood of the two components constituting the conjunction permitted us to assess the possibility that subjects judge the likelihood of conjunctions by averaging the likelihood of their component parts. The results were consistent with this possibility, and this interpretation was supported by analysis of the results in terms of functional measurement methodology.