Touch screen assays of behavioural flexibility and error characteristics in Eastern grey squirrels (<Emphasis Type="Italic">Sciurus carolinensis</Emphasis>)

Behavioural flexibility allows animals to adjust their behaviours according to changing environmental demands. Such flexibility is frequently assessed by the discrimination–reversal learning task. We examined grey squirrels’ behavioural flexibility, using a simultaneous colour discrimination–reversal learning task on a touch screen. Squirrels were trained to select their non-preferred colour in the discrimination phase, and their preferred colour was rewarded in a subsequent reversal phase. We used error rates to divide learning in each phase into three stages (perseveration, chance level and ‘learned’) and examined response inhibition and head-switching during each stage. We found consistent behavioural patterns were associated with each learning stage: in the perseveration stage, at the beginning of each training phase, squirrels showed comparable response latencies to correct and incorrect stimuli, along with a low level of head-switching. They quickly overcame perseveration, typically in one to three training blocks. In the chance-level stage, response latencies to both stimuli were low, but during initial discrimination squirrels showed more head-switches than in the previous stage. This suggests that squirrels were learning the current reward contingency by responding rapidly to a stimulus, but with increased attention to both stimuli. In the learned stage, response latencies to the correct stimulus and the number of head-switches were at their highest, whereas incorrect response latencies were at their lowest, and differed significantly from correct response latencies. These results suggest increased response inhibition and attention allowed the squirrels to minimise errors. They also suggest that errors in the ‘learned’ stage were related to impulsive emission of the pre-potent or previously learned responses.     

A behavioral intervention for teaching tackling skills to high school football athletes

We evaluated an intervention that combined task analysis and differential reinforcement for teaching tackling skills to 2 high school football athletes. As a result of intervention, both players tackled more proficiently in practice drills and maintained proficient tackling during games.     

WALKER PERCY,LANGUAGE, AND HOMO SINGULARIS

The novelist Walker Percy argued that modern science has a tremendous blind spot in its view of human nature. Unlike purely physical phenomena, which can be explained by the interaction of dyadic relationships, human beings must also be understood in terms of triadic relationships brought into being by symbolic language. The self brought into being by symbolic language is nonmaterial but real, and operates by different “laws” than those that govern dyadic relations. In making this case, Percy drew a sharp line between human and nonhuman language, a line that more recent developments in science has challenged. However, Percy's central point, that the agent of symbolic language cannot be understood within a materialist framework, remains valid.     

What Is and Is Not Ethnocentrism? A Conceptual Analysis and Political Implications

Conceptual analysis has not been systematically implemented in psychology, and many concepts have often been defined in different and contradictory ways. This article focuses on a conceptual clarification of ethnocentrism. It points out the conceptual confusion surrounding the term, reviews numerous definitions and operationalizations, and attempts to clarify it. Ethnocentrism is reconceptualized as a strong sense of ethnic group self‐centeredness, which involves intergroup expressions of ethnic group preference, superiority, purity, and exploitativeness, and intragroup expressions of ethnic group cohesion and devotion. It is conceptually and empirically distinguished from other concepts, such as outgroup negativity and mere ingroup positivity. The article presents a theoretical framework and related empirical analyses supporting the usefulness of reconceptualized ethnocentrism. It also details important and unique implications of reconceptualized ethnocentrism for political phenomena. It is expected that reliance on the clarified reconceptualization should enable researchers to systematically study ethnocentrism, its origins, and consequences.     

Emotional context at learning systematically biases memory for facial information

Emotion influences memory in many ways. For example, when a mood-dependent processing shift is operative, happy moods promote global processing and sad moods direct attention to local features of complex visual stimuli. We hypothesized that an emotional context associated with to-be-learned facial stimuli could preferentially promote global or local processing. At learning, faces with neutral expressions were paired with a narrative providing either a happy or a sad context. At test, faces were presented in an upright or inverted orientation, emphasizing configural or analytical processing, respectively. A recognition advantage was found for upright faces learned in happy contexts relative to those in sad contexts, whereas recognition was better for inverted faces learned in sad contexts than for those in happy contexts. We thus infer that a positive emotional context prompted more effective storage of holistic, configural, or global facial information, whereas a negative emotional context prompted relatively more effective storage of local or feature-based facial information     

Cognitive processes underlying lottery and sports gambling decisions: The role of stated probabilities and background knowledge

Two studies compared choice and underlying cognitive processes in equivalent decision tasks involving risk and uncertainty (lotteries versus sports gambles including displayed expert probability judgements). In sports gambles, background knowledge was triggered via information on team location, home or away. Otherwise, displayed risk information (stake, winnings, odds, and outcome probabilities) was controlled across gamble type. In a choice study, home win bets were chosen significantly more frequently than draws or away wins, compared to lottery equivalents. In a parallel study eliciting concurrent verbal protocols, participants made fewer evaluations of odds and probabilities, and more statements involving background knowledge in sports gambles. Furthermore, some sports gamble protocols indicated modifications of stated probabilities and decision strategies contingent on domain knowledge. It was concluded that stated probability revision and knowledge-based reasoning are key cognitive processes in sports gambling not normally applied in the lottery paradigms often employed in decision research.     

Presentism and the Notion of Existence

The aim of this paper is to make presentism a dynamic view of reality by basing it on a notion of dynamic existence, that is, on a notion of existence which has a dynamic character. The paper shows that both of the notions of existence which are used in metaphysical theories of time (in presentism and eternalism) have a static character and, while such a notion is useful for eternalists, it is useless for presentists if they want to make their view able to remain in agreement with our everyday experience and self-consistent. It is demonstrated that both empirical and theoretical arguments indicate that the presentist should replace the notion of this static existence with the notion of a dynamic existence and that this maneuver allows the presentist to treat his/her existential thesis as equivalent to the thesis that time flows. Not only does this strategy allow us to express presentism in a simple, homogenous way which remains in agreement with our experience, but also permits us to solve some of the difficult problems which presentism faces, such as, for example, the objection of triviality and the question about the rate of time passage. Moreover, such an approach to presentism allows us to solve fundamental metaphysical problems concerning time such as the problem of the openness of the future and the fixity of the past, direction of causation, and relations between presentism and persistence through time by endurance.     

Resemblance and general terms

Philosophical Studies -     

Interactions between conditioned stimuli for food and water in the rat

In two experiments rats were initially trained with one conditioned stimulus (CS) signalling food and another CS signalling water. The main purpose of the experiments was to examine the effects of presenting these stimuli in compound. Experiment 1 demonstrated that the level of conditioned responding to this compound was equal to that of a group for which the compound was composed of elements that had separately signalled the same reinforcer. Moreover, the level of this responding was greater than for a group that had received only compound conditioning. In the second experiment it was found that after the initial training, repeatedly pairing the compound with a single reinforcer resulted in an equivalent loss of conditioned responding to both elements. These findings suggest that the interaction between conditioned stimuli for food and water is facilitatory rather than inhibitory.