Do monkeys compare themselves to others?

Social comparisons are a fundamental characteristic of human behaviour, yet relatively little is known about their evolutionary foundations. Adapting the co-acting paradigm from human research (Seta in J Pers Soc Psychol 42:281–291, 1982. doi: 10.1037//0022-3514.42.2.281), we examined how the performance of a partner influenced subjects’ performance in long-tailed macaques (Macaca fascicularis). Using parallel testing in touch screen setups in which subjects had to discriminate familiar and novel photographs of men and women, we investigated whether accuracy and reaction time were influenced by partner performance and relationship quality (affiliate vs. non-affiliate). Auditory feedback about the alleged performance of the co-actor was provided via playback; partner performance was either moderately or extremely better or worse than subject performance. We predicted that subjects would assimilate to moderately different comparison standards as well as to affiliates and contrast away from extreme standards and non-affiliates. Subjects instantly generalized to novel pictures. While accuracy was not affected by any of the factors, long reaction times occurred more frequently when subjects were tested with a non-affiliate who was performing worse, compared to one who was doing better than them (80 % quantile worse: 5.1, better: 4.3 s). For affiliate co-actors, there was no marked effect (worse: 4.4, better: 4.6 s). In a control condition with no auditory feedback, subjects performed somewhat better in the presence of affiliates (M = 77.8 % correct) compared to non-affiliates (M = 71.1 %), while reaction time was not affected. Apparently, subjects were sensitive to partner identity and performance, yet variation in motivation rather than assimilation and contrast effects may account for the observed effects.     

Reasoning by exclusion in the kea (<Emphasis Type="Italic">Nestor notabilis</Emphasis>)

Reasoning by exclusion, i.e. the ability to understand that if there are only two possibilities and if it is not A, it must be B, has been a topic of great interest in recent comparative cognition research. Many studies have investigated this ability, employing different methods, but rarely exploring concurrent decision processes underlying choice behaviour of non-human animals encountering inconsistent or incomplete information. Here, we employed a novel training and test method in order to perform an in-depth analysis of the underlying processes. Importantly, to discourage the explorative behaviour of the kea, a highly neophilic species, the training included a large amount of novel, unrewarded stimuli. The subsequent test consisted of 30 sessions with different sequences of four test trials. In these test trials, we confronted the kea with novel stimuli that were paired with either the rewarded or unrewarded training stimuli or with the novel stimuli of previous test trials. Once habituated to novelty, eight out of fourteen kea tested responded to novel stimuli by inferring their contingency via logical exclusion of the alternative. One individual inferred predominantly in this way, while other response strategies, such as one trial learning, stimulus preferences and avoiding the negative stimulus also guided the responses of the remaining individuals. Interestingly, the difficulty of the task had no influence on the test performance. We discuss the implications of these findings for the current hypotheses about the emergence of inferential reasoning in some avian species, considering causal links to brain size, feeding ecology and social complexity.     

Economic strain and suicide risk: a qualitative analysis

Research at the individual level on economic strain and suicide has focused on unemployment; yet it remains unclear how unemployment and other economic strains actually affect suicide risk for the individual. In the present study Agnew's (1992, 2002), General Strain Theory was applied to a qualitative analysis of case files. Strain issues assessed include the role of goal blockage, economic loss, noxious work environments, anticipated strain, strain clusters, and vicarious strain in the generation of suicide risk. Data are from 62 cases of suicide involving economic strain from the files of an urban county medical examiner's office. The cases were classified into strain categories. Suicide risk was related to all categories of strain; however, economic strains were typically comorbid with additional strains in the genesis of suicide. Key auxiliary strains included anticipated loss of a home place, loss of a car, noxious social relationships, medical problems, death of loved ones, and involvement with the criminal justice system. Some evidence was found linking economic strain to the suicides of nonimpoverished persons. Economic strain and suicide would especially benefit by testing additional hypotheses on strain comorbidity. Unemployment combined with an anticipated eviction from one's home is recommended as a particular point of departure for future work.     

Beat them or ban them: the characteristics and social functions of anger and contempt

This article reports 3 studies in which the authors examined (a) the distinctive characteristics of anger and contempt responses and (b) the interpersonal causes and effects of both emotions. In the 1st study, the authors examined the distinction between the 2 emotions; in the 2nd study, the authors tested whether contempt could be predicted from previous anger incidents with the same person; and in the 3rd study, the authors examined the effects of type of relationship on anger and contempt reactions. The results of the 3 studies show that anger and contempt often occur together but that there are clear distinctions between the 2 emotions: Anger is characterized more by short-term attack responses but long-term reconciliation, whereas contempt is characterized by rejection and social exclusion of the other person, both in the short-term and in the long-term. The authors also found that contempt may develop out of previously experienced anger and that a lack of intimacy with and perceived control over the behavior of the other person, as well as negative dispositional attributions about the other person, predicted the emergence of contempt.     

Alzheimer's disease in Down syndrome: neurobiology and risk

Down syndrome (DS) is characterized by increased mortality rates, both during early and later stages of life, and age-specific mortality risk remains higher in adults with DS compared with the overall population of people with mental retardation and with typically developing populations. Causes of increased mortality rates early in life are primarily due to the increased incidence of congenital heart disease and leukemia, while causes of higher mortality rates later in life may be due to a number of factors, two of which are an increased risk for Alzheimer's disease (AD) and an apparent tendency toward premature aging. In this article, we describe the increase in lifespan for people with DS that has occurred over the past 100 years, as well as advances in the understanding of the occurrence of AD in adults with DS. Aspects of the neurobiology of AD, including the role of amyloid, oxidative stress, Cu/ZN dismutase (SOD-1), as well as advances in neuroimaging are presented. The function of risk factors in the observed heterogeneity in the expression of AD dementia in adults with DS, as well as the need for sensitive and specific biomarkers of the clinical and pathological progressing of AD in adults with DS is considered.     

Linguistic-pragmatic factors in interpreting disjunctions

' The connective or can be treated as an inclusive disjunction or else as an exclusive disjunction. Although researchers are aware of this distinction, few have examined the conditions under which each interpretation should be anticipated. Based on linguistic-pragmatic analyses, we assume that interpretations are initially inclusive before either (a) remaining so, or (b) becoming exclusive by way of an implicature (but not both). We point to a class of situations that ought to predispose disjunctions to inclusive interpretations and to situations that encourage exclusive interpretations. A disjunction's ultimate interpretation is based on its potential informativeness, where the interpretation of the disjunctive utterance having the smallest number of true conditions is considered most informative. Our investigation leads to five experiments employing arbitrary materials. Among the problems expected to encourage inclusive interpretations are those that present disjunctions in the antecedents of conditionals and in question forms. The best candidates to produce implicatures are those disjunctions that underdetermine an expected conjunctive conclusion, although other disjunctive utterances that are more informative as exclusive are discussed and tested.     

The (Dis)similarity of a Minority Religion to Its Broader Religious Context: The Case of American Jews

While much research shows the relationship between individual-level variables, such as Jewish background, education, age, and income and an individual’s Jewish identity, very little research has systematically addressed the question of community context, either general or Jewish, as a factor influencing Jewish religious or ethnic identity. This lack of research has been partially a result of the lack of an adequate data set to facilitate such analysis. Using the newly-aggregated Decade 2000 data set, with its 19,800 cases spread across 22 Jewish communities, we find that despite the anecdotal evidence and the logic that suggests that environment impacts behavior, the environmental impact on Jewish identity is clearly weak. Individual characteristics are much stronger than community context in explaining variations in the strength of Jewish identity.     

A behavioural-pharmacological treatment of dually addicted patients

maintenance appears to be an effective means of treating narcotic addiction both because it blocks the effects of heroin and because patients are willing to accept methadone treatment. However, alcoholism has been found commonly to complicate methadone maintenance and to result in treatment failure. The regular ingestion of disulfiram, a drug which blocks ethanol metabolism, could provide a solution to this problem, but alcoholics tend not to persist in taking this drug, because unlike methadone it possesses no reinforcing properties. This paper describes a novel technique whereby the reinforcing action of methadone has been employed to maintain disulfiram-taking, and thus to arrest alcohol abuse and consequent treatment failure.