Kea cooperate better with sharing affiliates

Controlled studies that focus on intraspecific cooperation tasks have revealed striking similarities, but also differences, in abilities across taxa as diverse as primates, fish, and birds. Such comparisons may provide insight into the specific socio-ecological selection pressures that led to the evolution of cooperation. Unfortunately, however, compared to primates data on birds remain relatively scarce. We tested a New Zealand psittaciform, the kea, in a dyadic cooperation task using the loose-string design. During trials our subjects were in separate compartments, but obtained a common reward that could be divided multiple ways, allowing the examination of reward division effects. Ten individuals were tested twice in 44 combinations of partners. Dyads with a high affiliation score attempted to cooperate more often and were also more often successful in doing so. Furthermore, dyads that shared rewards more equally seemed to be more likely to attempt cooperation in the next trial. Like other bird and some monkey species, but unlike, for example, chimpanzees, kea did not spontaneously show understanding of either the role of the partner or the mechanism behind the cooperation task. This may point to true disparities between species, but may also be due to differences in task design and/or the amount of exposure to similar tasks and individual skills of the subjects.     

Passion for a Cause: How It Affects Health and Subjective Well‐Being

Using the dualistic model of passion (Vallerand et al., 2003), this research investigated how harmonious passion (HP) or obsessive passion (OP) for a cause can affect volunteers' health and subjective well‐being. Three studies with volunteers for local (local emergency crises and community help) and international (humanitarian missions) causes assessed physical and psychological health using cross‐sectional and longitudinal designs. Study 1 (N = 108) showed that HP was positively related to satisfaction with one's involvement in the cause and unrelated to physical injuries due to cause involvement. OP was unrelated to satisfaction but positively associated with injuries. Findings were replicated in Study 2 (N = 83). Moreover, self‐neglect mediated the positive and negative effects of HP and OP, respectively, on injuries. Study 3 (N = 77) revealed that HP predicted an increase in satisfaction and health over a 3‐month mission. OP predicted an increase in physical symptoms and a decrease in health. Furthermore, OP before a mission was positively related to self‐neglect that was positively associated with physical symptoms after a mission. OP also positively predicted rumination that was conducive to posttraumatic stress disorder. HP was unrelated to these variables. Findings underscore the role of passion for a cause in predicting intrapersonal outcomes of volunteers.     

Fear expression and return of fear following threat instruction with or without direct contingency experience

Prior research showed that mere instructions about the contingency between a conditioned stimulus (CS) and an unconditioned stimulus (US) can generate fear reactions to the CS. Little is known, however, about the extent to which actual CS–US contingency experience adds anything beyond the effect of contingency instructions. Our results extend previous studies on this topic in that it included fear potentiated startle as an additional dependent variable and examined return of fear (ROF) following reinstatement. We observed that CS–US pairings can enhance fear reactions beyond the effect of contingency instructions. Moreover, for all measures of fear, instructions elicited immediate fear reactions that could not be completely overridden by subsequent situational safety information. Finally, ROF following reinstatement for instructed CS+s was unaffected by actual experience. In summary, our results demonstrate the power of contingency instructions and reveal the additional impact of actual experience of CS–US pairings.     

EFFECTS OF INTERMITTENT PUNISHMENT ON SELF-INJURIOUS BEHAVIOR: AN EVALUATION OF SCHEDULE THINNING

Although the use of punishment often raises ethical issues, such procedures may be needed when the reinforcers that maintain behavior cannot be identified or controlled, or when competing reinforcers cannot be found. Results of several studies on the effects of intermittent schedules of punishment suggest that therapists must use fairly rich schedules of punishment to suppress problem behavior. However, residential caretakers, teachers, and parents often have difficulty implementing programs that require constant monitoring of the client's behavior. In this study, we examined the feasibility of gradually thinning the delivery of punishment from a continuous schedule to an intermittent schedule during the course of treatment for self-injurious behavior (SIB). Results of functional analyses for 5 individuals who had been diagnosed with profound mental retardation indicated that their SIB was not maintained by social consequences. Treatment with continuous schedules of time-out (for 1 participant) or contingent restraint (for the other 4 participants) produced substantial reductions in SIB. When they were exposed to intermittent schedules of punishment (fixed-interval [FI] 120 s or FI 300 s), SIB for all but 1 of the participants increased to levels similar to those observed during baseline. For these 4 participants, the schedule of punishment was gradually thinned from continuous to FI 120 s or FI 300 s. For 2 participants, SIB remained low across the schedule changes, demonstrating the utility of thinning from continuous to intermittent schedules of punishment. Results for the other 2 participants showed that intermittent punishment was ineffective, despite repeated attempts to thin the schedule.     

AN ANALYSIS OF REINFORCER SUBSTITUTABILITY USING OBJECT MANIPULATION AND SELF-INJURY AS COMPETING RESPONSES

The concept of reinforcer substitutability proposes a continuum of interactions among reinforcers in a given situation. At one end of this continuum, reinforcers are substitutable, with one reinforcer being readily traded for another. We conducted an analysis of reinforcers that were substitutable with those produced by self-injurious behavior (SIB). Three individuals with profound developmental disabilities, whose SIB appeared to be maintained by automatic reinforcement, participated. Results of three experiments showed that (a) object manipulation and SIB were inversely related when leisure materials and SIB were concurrently available, with participants showing almost complete preference for object manipulation; (b) attempts to reduce SIB using the preferred objects as reinforcers in differential reinforcement contingencies were unsuccessful for all 3 participants; and (c) participants' preferences for SIB or object manipulation systematically changed when reinforcer cost (the amount of effort required to obtain the object) was varied. Results of the three experiments illustrate the importance of examining interactions among concurrently available reinforcers when conducting reinforcer assessments.     

Theme and variation in the development of the first transitional object

In our research we have been attempting to elucidate the phenomenon we have labelled the 'first transitional object'. In this paper we have focused primarily on some dimensions along which the child can vary in his use of the first transitional object. We have pointed to the fact that some infants first come in contact with the 'blanket' at the age of three months, and this seems to be a critical time period for regular contact with the first transitional object. While there are variations in the child's attachment to the first transitional object from the very beginning, age two appears to be a crucial time when the intensity of the child's attachment to the 'blanket' becomes established. Most children seem to give up the first transitional object between five and six years of age, and an example of the disruption of this process was presented. An attempt was made to put these findings within a developmental context, while other variables which affect the fate of the first transitional object were also explored.     

Procedures for synthesizing ratio judgements

Requirements which seem reasonable for functions synthesizing judgements (quantities or their ratios), in particular separability, associativity or bisymmetry, cancellativity, consensus, reciprocal or homogeneity properties are investigated and all functions satisfying them are determined.     

The effectiveness of visual and gustatory conditioned stimuli in human classical aversive conditioning with electric shock

Thirty-six undergraduate volunteers, divided into three equal groups, were given electric shock while sipping a colored, unflavored solution (Group I): a flavored, colorless solution (Group 2); or a colored, flavored solution (Group 3), in order to determine whether human Ss respond differentially to visual and gustatory cues when the UCS is aversive electric shock. Using a standard classical discrimination procedure, the CS + was blue water for Group 1, citric acid solution for Group 2, and blue citric acid solution for Group 3. For all groups the CS- was plain water, which was never paired with electric shock. The dependent variables were derived from Staats' A-R-D theory: attitudinal change (A) and a performance measure of sip-size taken during conditioning trials (D) both confirmed the hypothesis that taste can be an effective CS when the UCS is shock, in contrast to results typically obtained with rats where visual but not taste cues are effective with a shock UCS.