Spatial multiple-choice matching in a harbour seal (Phoca vitulina): differential encoding of landscape versus local feature information?

The nature of spatial information used for memorizing and recalling places is largely unclear. Earlier studies tested integration of geometric and feature information mostly during reorientation in artificial environments without including time as a memory-critical component. Here, we tested a harbour seal in a delayed matching-to-sample task (DMTS) in a familiar environment under two spatial multiple-choice conditions. The feature condition consisted of a DMTS task with four comparison stimuli presented on fixed positions in a classic matching apparatus and was designed to make stimulus features the most prominent information. The landscape condition consisted of a DMTS task in a familiar environment with four places marked by comparison stimuli and allowed the use of all available spatial information including geometrical and feature information. The seal's performance was impaired by delays of 3, 6, 9 or 12 s only in the feature condition; a delay of 12 s resulted in chance level performance. Replacing the comparison stimuli at the apparatus with identical spheres resulted in impaired performance. Performance in the landscape condition was impaired neither by delays nor by replacing comparison stimuli with spheres. Landscape information obviously was encoded redundantly and could be recalled more reliably and longer than feature information, which reveals feature information to be a less valuable type of spatial information for memorizing and recalling places.     

The effectiveness and ethical justification of psychiatric outpatient commitment

Studies link involuntary outpatient commitment with improved patient outcomes, fueling debate on its ethical justification. This study compares inpatient utilization for committed outpatients in the 1990s with those who were not under outpatient civil commitment orders. Findings reveal committed outpatients had higher utilization of inpatient services and restraint episodes prior to their commitment compared with a control group. Committed outpatients also were more likely to have been on discharge status at the time of admission, have been admitted involuntarily under emergency legal procedures, and have had a greater number of admissions and hospital days prior to their commitment. Following commitment, patients had fewer hospitalizations, shorter lengths of stay, fewer seclusion episodes and hours, and fewer restraint episodes and hours. Findings are discussed within the context of parens patriae and therapeutic jurisprudence, and support medical and public policy justifications for ethical uses of outpatient civil commitment laws for seriously mentally ill patients.     

Vagueness-Adaptive Logic: A Pragmatical Approach to Sorites Paradoxes

Kripke-completeness of every classical modal logic with Sahlqvist formulas is one of the basic general results on completeness of classical modal logics. This paper shows a Sahlqvist theorem for modal logic over the relevant logic Bin terms of Routley-Meyer semantics. It is shown that usual Sahlqvist theorem for classical modal logics can be obtained as a special case of our theorem.     

Motivation Gains in Computer‐Supported Groups1

One challenge in computer‐supported groups is the maintenance of high performance motivation of group members because face‐to‐face interaction and social control are restricted. Based on research on the Kohler effect (Hertel, Kerr, & Messe, 2000), we expected high motivation of group members when their individual effort is highly instrumental for the group's success. First, a task paradigm was developed and validated to measure motivation in a computer task. Then, this paradigm was used to explore group members’ motivation in computer‐supported dyads without face‐to‐face contact. Consistent with our expectations, motivation (and performance) of the group members was high and even exceeded the baseline of individual work (thus revealing motivation gains) when the individual's contribution was highly instrumental for the dyad's success (i.e., weaker coworker under conjunctive task demand). When instrumentality was low (i.e., weaker coworker under additive task demand), inconclusive results were obtained. Overall, the results demonstrate that motivation gains can be produced in computer‐supported dyads, even without face‐to‐face interaction.     

The effects of presentation time on preference for curvature of real objects and meaningless novel patterns

Objects with curved contours are generally preferred to sharp‐angled ones. In this study, we aim to determine whether different presentation times influence this preference. We used images of real objects (experiment 1) and meaningless novel patterns (experiment 2). Participants had to select one of two images from a contour pair, curved and sharp‐angled versions of the same object/pattern. With real objects, the preference for curved versions was greatest when presented for 84 ms, and it faded when participants were given unlimited viewing time. Curved meaningless patterns were preferred when presented for 84 and 150 ms. However, in contrast to real objects, preference for meaningless patterns increased significantly in the unlimited viewing time condition. Participants discriminated poorly between the two versions (curved and sharp‐angled) of the meaningless patterns in the 84‐ and 150‐ms presentations (experiment 3). Therefore, in short times with meaningless patterns, participants selected mostly the curved version without being aware of the difference. In conclusion, presentation time, type of stimulus, and their interaction influence preference for curvature.     

Abstract concepts,compositionality, and the contextualism-invariantism debate

Invariantists argue that the notion of concept in psychology should be reserved for knowledge that is retrieved in a context-insensitive manner. Contextualists argue that concepts are to be understood in terms of context-sensitive ad hoc constructions. I review the central empirical evidence for and against both views and show that their conclusions are based on a common mischaracterization of both theories. When the difference between contextualism and invariantism is properly understood, it becomes apparent that the way the question of stability is currently investigated will not lead to a consensus. Instead of focusing directly on stability, we should turn our attention to other desiderata on a theory of concepts. In particular, I show that invariantism, but not contextualism, fails to account for compositionality and abstract concepts.     

Neophobia is negatively related to reversal learning ability in females of a generalist bird of prey,the Chimango Caracara, <Emphasis Type="Italic">Milvago chimango</Emphasis>

In an ever-changing environment, the ability to adapt choices to new conditions is essential for daily living and ultimately, for survival. Behavioural flexibility allows animals to maximise survival and reproduction in novel settings by adjusting their behaviour based on specific information and feedback acquired in their current environments. However, a growing body of evidence indicates that an individual’s personality type can limit the extent to which the individual might behave flexibly, by influencing the way an individual pays attention to novelty and how much information it collects and stores, which in turn affects the individual’s decision-making and learning process. In this study, the behavioural flexibility of a generalist predator, the Chimango Caracara, Milvago chimango, was analysed using the reversal learning paradigm, focusing on the comparison between age classes, and the relation of learning flexibility with a personality trait, the level of neophobia. Due to the low number of male individuals captured, this study was carried out only with female birds. The results showed that age had no significant effect either on the acquisition of a stimulus-reward association, or on the capacity of reversing this previously learned association. Reversal of the response was a harder task for these birds in comparison with the initial acquisition process. The individual’s performances in the learning tasks seemed to be uncorrelated with each other, suggesting that they involve different neural mechanisms. Contrary to the general pattern observed in the majority of previous work on personality and cognition in non-human animals, the level of neophobia did not correlate with the initial associative learning performance in both adults and juveniles, yet it showed a significant negative relationship with reversal learning ability, mainly in the regressive phase of this task, for the two age classes. Our results suggest that the predatory and generalist lifestyle of female individuals of M. chimango along with the selective pressures of the environment of the individuals studied might play a critical role in the degree and direction of the linkage between novelty response and learning flexibility observed in this study.