The cognitive capabilities of farm animals: categorisation learning in dwarf goats (Capra hircus)

The ability to establish categories enables organisms to classify stimuli, objects and events by assessing perceptual, associative or rational similarities and provides the basis for higher cognitive processing. The cognitive capabilities of farm animals are receiving increasing attention in applied ethology, a development driven primarily by scientifically based efforts to improve animal welfare. The present study investigated the learning of perceptual categories in Nigerian dwarf goats (Capra hircus) by using an automated learning device installed in the animals' pen. Thirteen group-housed goats were trained in a closed-economy approach to discriminate artificial two-dimensional symbols presented in a four-choice design. The symbols belonged to two categories: category I, black symbols with an open centre (rewarded) and category II, the same symbols but filled black (unrewarded). One symbol from category I and three different symbols from category II were used to define a discrimination problem. After the training of eight problems, the animals were presented with a transfer series containing the training problems interspersed with completely new problems made from new symbols belonging to the same categories. The results clearly demonstrate that dwarf goats are able to form categories based on similarities in the visual appearance of artificial symbols and to generalise across new symbols. However, the goats had difficulties in discriminating specific symbols. It is probable that perceptual problems caused these difficulties. Nevertheless, the present study suggests that goats housed under farming conditions have well-developed cognitive abilities, including learning of open-ended categories. This result could prove beneficial by facilitating animals' adaptation to housing environments that favour their cognitive capabilities.     

Social Value Orientation and information search in social dilemmas: An eye-tracking analysis

Previous work has demonstrated that Social Value Orientation (SVO) is related to cooperative behavior in social dilemmas. However, little is known concerning the underlying processes. In two eye-tracking studies investigating decisions in money allocation tasks (Experiment 1) and Public Good Dilemmas (Experiment 2), we show that differences in SVO are accompanied by consistent differences in information search. Decision time, number of fixations, the proportion of inspected information, the degree of attention towards the others’ payoffs, and the number of transitions from and towards others’ payoffs gradually increase with absolute SVO deviation from a pure selfish orientation. Overall these effects seem to be similar for individuals caring positively (i.e., cooperative) or negatively (i.e., competitive) about others. The fact that changes are gradual instead of abrupt indicates that differences in SVO seem to be related to gradual changes in weights given to outcomes for self and others.     

Enhanced Encoding of Nonverbal Cues Bipolar Illness in Males

Twenty-five affectively bipolar males were found to possess an enhanced ability to encode nonverbal cues when compared to matched controls. This ability was present during both manic and euthymic phases.     

Content Analysis of Multiple Messages in Suicide Notes*

ABSTRACT: Two hundred twenty individuals who committed suicide and who left notes, when compared with 813 non-note writers, were significantly more likely to be white, female, and, if female, to have any other marital status than “widowed.” With respect to method, the results indicated that note writers were more apt to have committed suiced with “Drugs” and less apt to have used “Other” methods. The question is raised as to whether or not note writers can be accepted as representative of the whole group of those who commit suicide. In 195 suicide notes for which content was available for analysis, the relative percentages of statements containing advice, instructions, and requests (31), other-directed positive affect (19), acknowledgment of wrongdoing (7), and hostile affect (5) were the same in the entire sample as in subsamples of age, sex, and marital status. Only for a few specific content categories did the relative frequency of content vary significantly with age, sex, or marital status. Advantages of the present method of content analysis are discussed, and suggestions for further research in this area are offered.     

Base-rate neglect as a function of base rates in probabilistic contingency learning

When humans predict criterion events based on probabilistic predictors, they often lend excessive weight to the predictor and insufficient weight to the base rate of the criterion event. In an operant analysis, using a matching-to-sample paradigm, Goodie and Fantino (1996) showed that humans exhibit base-rate neglect when predictors are associated with criterion events through physical similarity. In partial replications of their studies, we demonstrated similar effects when the predictors resembled the criterion events in terms of similarly skewed base rates. Participants' predictions were biased toward the more (or less) frequent criterion event following the more (or less) frequent predictor. This finding adds to the growing evidence for pseudocontingencies (Fiedler & Freytag, 2004), a framework that stresses base-rate influences on contingency learning.     

Language: A Toolbox for Sharing and Influencing Social Reality

ABSTRACT— The key role of language is often neglected in explicitly formulated theories of cognition, affect, and social behavior. Implicitly, though, the relationship between language and mind is at the heart of psychological science. Two major research programs—linguistic universals and linguistic relativity—originate in opposite philosophical positions, assuming either that language reflects the mind's ideas and free will or that language differences govern and restrict the mind. However, modern psychological research was able to begin illuminating the power and richness of linguistic influences only after the priority debate was given up and language and cognition were treated as integral parts of the same process. Beyond the confines of referential communication, conceived as cooperative transfer of symbols referring to common world knowledge, some of the most intriguing phenomena are detached from referential bonds, reflecting unintended, emergent, or even random outcomes of verbal interaction. Indeed, the effectiveness of verbal priming may be actually contingent on language users' failure to understand the primes' referential meanings and implications.     

Barking up the wrong tree? Industry funding of academic research

This case raises ethical issues involving conflicts of interest arising from industrial funding of academic research; ethical responsibilities of laboratories to funding agencies; ethical responsibilities in the management of a research lab; ethical considerations in appropriate research design; communication in a research group; communication between advisor and graduate student; responsibilities of researchers for the environment; misrepresentation or withholding of scientific results.     

Hair cortisol in relation to acute and post-traumatic stress symptoms in children and adolescents

Background: We report on the preliminary results of two independent studies that (1) compare the hair cortisol concentrations (HCC) of healthy controls with patients displaying post-traumatic stress symptoms (PTSS, study 1+2), (2) investigate whether pre-trauma HCC are predictive for the development of acute stress symptoms (ASS) and PTSS (study 1) and (3) determine whether HCC correlate with PTSS in a clinical sample of children (study 2).

Methods: In study 1, the clinical symptoms of 35 minors were examined one (T1) and seven weeks (T2) after surgery following an accident. Hair samples were taken after the accident that reflect cortisol secretion over the past three months before the accident (healthy controls). In study 2, HCC and PTSS symptoms were cross-sectionally assessed in 22 minors who had experienced a psychological trauma.

Results: The HCC of patients with PTSS were lower than the HCC of healthy controls (study 1+2). Secondary analyses showed that HCC were significantly lower in male PTSS patients than in male healthy controls, whereas the HCC in females were comparably low in both groups. Pre-trauma HCC did not predict the total ASS and PTSS scores (study 1) and HCC were not directly related to the total PTSS scores (study 2).