Sex differences in discrimination reversal learning in the guppy

In several mammalian and avian species, females show a higher performance than males in tasks requiring cognitive flexibility such as the discrimination reversal learning. A recent study showed that female guppies are twice as efficient as males in a reversal learning task involving yellow–red discrimination, suggesting a higher cognitive flexibility in female guppies. However, the possibility exists that the superior performance exhibited by females does not reflect a general sex difference in cognitive abilities, but instead, is confined to colour discrimination tasks. To address this issue, we compared male and female guppies in two different discrimination reversal learning tasks and we performed a meta-analysis of these experiments and the previous one involving colour discrimination. In the first experiment of this study, guppies were tested in a task requiring them to learn to select the correct arm of a T-maze in order to rejoin a group of conspecifics. In experiment 2, guppies were observed in a numerical task requiring them to discriminate between 5 and 10 dots in order to obtain a food reward. Although females outperformed males in one condition of the T-maze, we did not find any clear evidence of females’ greater reversal learning performance in either experiment. However, the meta-analysis of the three experiments supported the hypothesis of females’ greater reversal learning ability. Our data do not completely exclude the idea that female guppies have a generally higher cognitive flexibility than males; however, they suggest that the size of this sex difference might depend on the task.     

Do domestic dogs (<Emphasis Type="Italic">Canis lupus familiaris</Emphasis>) perceive the Delboeuf illusion?

In the last decade, visual illusions have been repeatedly used as a tool to compare visual perception among species. Several studies have investigated whether non-human primates perceive visual illusions in a human-like fashion, but little attention has been paid to other mammals, and sensitivity to visual illusions has been never investigated in the dog. Here, we studied whether domestic dogs perceive the Delboeuf illusion. In human and non-human primates, this illusion creates a misperception of item size as a function of its surrounding context. To examine this effect in dogs, we adapted the spontaneous preference paradigm recently used with chimpanzees. Subjects were presented with two plates containing food. In control trials, two different amounts of food were presented in two identical plates. In this circumstance, dogs were expected to select the larger amount. In test trials, equal food portion sizes were presented in two plates differing in size: if dogs perceived the illusion as primates do, they were expected to select the amount of food presented in the smaller plate. Dogs significantly discriminated the two alternatives in control trials, whereas their performance did not differ from chance in test trials with the illusory pattern. The fact that dogs do not seem to be susceptible to the Delboeuf illusion suggests a potential discontinuity in the perceptual biases affecting size judgments between primates and dogs.     

The influence of confidence on associations among personal attitudes, perceived injunctive norms, and alcohol consumption

Social norms theories hold that perceptions of the degree of approval for a behavior have a strong influence on one's private attitudes and public behavior. In particular, being more approving of drinking and perceiving peers as more approving of drinking, are strongly associated with one's own drinking. However, previous research has not considered that students may vary considerably in the confidence in their estimates of peer approval and in the confidence in their estimates of their own approval of drinking. The present research was designed to evaluate confidence as a moderator of associations among perceived injunctive norms, own attitudes, and drinking. We expected perceived injunctive norms and own attitudes would be more strongly associated with drinking among students who felt more confident in their estimates of peer approval and own attitudes. We were also interested in whether this might differ by gender. Injunctive norms and self-reported alcohol consumption were measured in a sample of 708 college students. Findings from negative binomial regression analyses supported moderation hypotheses for confidence and perceived injunction norms but not for personal attitudes. Thus, perceived injunctive norms were more strongly associated with own drinking among students who felt more confident in their estimates of friends' approval of drinking. A three-way interaction further revealed that this was primarily true among women. Implications for norms and peer influence theories as well as interventions are discussed.     

Breaking down unitization: Is the whole greater than the sum of its parts?

Memory impairments are often observed in aging. Specifically, older adults have difficulty binding together disparate elements (relational memory). We have recently shown that a cognitive strategy known as unitization can mitigate impaired relational learning in the transverse patterning task (TP) in both amnesia and healthy aging. This strategy allows items to be fused together through an interaction such that one item acts upon another. In the context of TP, unitization is comprised of three component processes: (1) fusion, (2) motion, and (3) semantic comprehension of action/consequence sequences. Here, we examine which of these components are sufficient to mitigate age-related impairments. Four groups of older adults were given either the full unitization strategy or one of the three component strategies. Each group of older adults showed impairments in memory for the relations among items under standard training instructions relative to a threshold that marks learning of a winner-take-all rule (elemental threshold). However, participants who were given either the full unitization strategy or the action/consequence-only strategy showed improved performance, which was maintained following the 1-hour delay. Therefore, semantically rich action/consequence interactions are sufficient to mitigate age-related relational memory impairments.     

Probabilistic Logic Under Coherence, Conditional Interpretations, and Default Reasoning

We study a probabilistic logic based on the coherence principle of de Finetti and a related notion of generalized coherence (g-coherence). We examine probabilistic conditional knowledge bases associated with imprecise probability assessments defined on arbitrary families of conditional events. We introduce a notion of conditional interpretation defined directly in terms of precise probability assessments. We also examine a property of strong satisfiability which is related to the notion of toleration well known in default reasoning. In our framework we give more general definitions of the notions of probabilistic consistency and probabilistic entailment of Adams. We also recall a notion of strict p-consistency and some related results. Moreover, we give new proofs of some results obtained in probabilistic default reasoning. Finally, we examine the relationships between conditional probability rankings and the notions of g-coherence and g-coherent entailment.     

The Good Professor

This paper seeks to provide a philosophical analysis of the features of an excellent professor, but a well-balanced one, professionally speaking. What makes for excellence in research, teaching and service is explored in some detail, with attention paid to the contexts of four-year colleges and comprehensive universities in the united states.     

The Philosophy of Joel Feinberg*

This paper is offered as a tribute to Joel Feinberg. The first section of the paper applies Feinberg’s analysis of freedom of expression to a contemporary case of academic freedom. The second section engages Feinberg’s work on rights and punishment. The paper ends with numerous quotations from Feinberg’s vast array of writings, words that express his ideas on a number of important problems that occupied his mind throughout his fruitful and influential career.     

Evaluation and training of Executive Functions in genocide survivors. The case of Yazidi children

Executive Functions (EFs) development is critically affected by stress and trauma, as well as the socioeconomic context in which children grow up (Welsh, Nix, Blair, Bierman, & Nelson, 2010, Journal of Educational Psychology, 102 , 43–53). Research in this field is surprisingly lacking in relation to war contexts. This study represents a first attempt at addressing this topic by evaluating EFs in Yazidi children. The Yazidi community is an ethnic and religious minority living in Iraq. From August 2014 onwards, the Yazidi community has been the target of several atrocities perpetrated by ISIS and described as genocide by the international community at large. The University of Trieste, thanks to a program financed by the Friuli Venezia Giulia Region, developed a study aimed at (a) evaluating hot and cool EFs in children living in a war context and (b) developing a specific training method to enhance hot and cool EFs in Yazidi children of preschool age (N = 53). Data related to this group of children were compared with a sample of typically developing Italian children randomly assigned to either an EFs training group (N = 55) or a passive control group (N = 51). Results indicate different baselines in EFs in Yazidi and Italian samples and a significant effect of the program on both trained groups, especially in tasks measuring hot EFs. Data are discussed in terms of hot and cool EFs in children growing in adverse environments, as well as the evaluation of educational and developmental opportunities to prevent children who survived genocide from becoming a ‘lost generation’. A video abstract of this article can be viewed at https://youtu.be/7t_08TbxR_8 .