Post-retrieval effects of icv infusions of hemicholinium in mice are dependent on the age of the original memory

CF-1 male mice were trained in an inhibitory avoidance task using a high footshock (1,2 mA, 50 Hz, 1 sec) in order to reduce the influence of extinction on retention performance. At 2, 7, 14, or 30 d after training, the first retention test was performed and hemicholinium (HC-3, 1.0 microg/mice), a specific inhibitor of high-affinity choline uptake in brain cholinergic neurons, was given intracerebroventricularly immediately after. Twenty four hours after treatment, mice were tested in an inhibitory avoidance task during five consecutive days, each 24 h apart. Retention performance was impaired by HC-3 when the first re-exposure took place at 2, 7, or 14 d, but the effect was no longer seen when re-exposure occurred 30 d after training. We did not find spontaneous recovery 21 d after training, when memory was retrieved 2 d after training and HC-3 was given immediately after. Although we cannot definitively discard a retrieval deficit, this lack of spontaneous recovery is in accordance with the storage-deficit interpretation. These results confirm and extend previous ones, suggesting that central cholinergic mechanisms are involved in the hypothetical reconsolidation memory processes of an inhibitory avoidance task in mice and also suggest that this participation depends on the "age" of the original memory trace. This implies that the vulnerability of a reactivated memory to a specific treatment, as the one used in this study, inversely correlates with the age of the original memory, and it is likely to determine memory reconsolidation processes.     

Similes on the Internet have explanations

We searched the Internet for expressions linking topics, such as crime, and vehicles, such as disease, as similes (crime is like a disease) and as metaphors (crime is a disease). We counted the number of times the expressions were accompanied by explanations (crime is like a disease because it spreads by direct personal influence). Similes were more likely than metaphors to be accompanied by explanations. Similes may be preferred if a writer wants to express an out-of-the-ordinary relation between the topic and the vehicle.     

Psychometric properties of a European Spanish version of the Perceived Stress Scale (PSS)

This paper presents evidence from a heterogeneous sample of 440 Spanish adults, for the reliability and validity of a European Spanish version of the Perceived Stress Scale (PSS), designed to measure the degree to which situations in one's life are appraised as stressful. The European Spanish version PSS (14-item) demonstrated adequate reliability (internal consistency, alpha = .81, and test-retest, r = .73), validity (concurrent), and sensitivity. Additional data indicate adequate reliability (alpha = .82, test-retest, r = .77), validity, and sensitivity of a 10-item short version of the PSS.     

The relation of lifetime cognitive activity and lifetime access to resources to late-life cognitive function in older African Americans

Research in older Caucasians has demonstrated that cognitive activity is related to cognitive function in late adulthood. Knowledge of this association is limited in older minority populations. We examined the relation of cognitive activity and access to cognitive resources, with cognitive function in a group of 108 older African Americans. We constructed two scales to measure the frequency of cognitive activity and the presence of resources that promote cognitive activity during early and late life. Both measures had high internal consistency and the cognitive activity scale had adequate temporal stability over a 4-week interval. In analyses that controlled for age and education, more frequent lifetime cognitive activity was related to current cognitive function, but lifetime cognitive resources only approached significance. The results suggest that both measures are psychometrically sound in a minority population and that lifetime cognitive activity may contribute to current cognitive function in African Americans.     

Relations among mothers' expressivity, children's effortful control, and their problem behaviors: a four-year longitudinal study

Longitudinal relations between mothers' expressivity, children's effortful control, and their problem behaviors were examined when children (N = 181) were 6.5-10 years old (T2) and again 2 (T3) and 4 (T4) years later. Mothers reported on their expression of positive and negative dominant emotion. Mothers and teachers reported on children's effortful control and externalizing and internalizing problem behaviors. In structural equation models, variables exhibited consistency over time. Further, the relation between mothers' expressivity (positive minus negative dominant emotion) at T2 and children's externalizing problems at T4 was mediated by T3 effortful control. The same process of mediation was significant for teacher- but not mother-reported internalizing problems. The results provide one explanation for how emotion-related socializing behaviors influence children's problem behaviors.     

Goal orientation, motivational climate, and dispositional flow of high school students engaged in extracurricular physical activity

The purpose of this study was to examine the role of goal orientation, motivational climate, and dispositional flow in physical education lessons on extracurricular involvement in physical activity. Questionnaires were administered to 1,103 (792 athletes; 311 nonathletes) secondary school students (M age = 14.3 yr., SD = 0.7). Analysis showed significant mean differences between groups on goal orientation and dispositional flow in physical education lessons, but none for perception of motivational climate. These findings suggest that dispositional variables are related to extracurricular involvement in physical activity.     

Organ sales and moral distress

abstract The possibility that organ sales by living adults might be made legal is morally distressing to many of us. However, powerful arguments have been provided recently supporting legalisation (I consider two of those arguments: the Consequentialist Argument and the Autonomy Argument). Is our instinctive reaction against a market of organs irrational then? The aim of this paper is not to prove that legalization would be immoral, all things considered, but rather to show, first, that there are some kinds of arguments, offered in favour of legalisation, that are, in an important sense, illegitimate, and second, that even if legalisation might not be wrong all things considered, there are good reasons for our negative moral intuitions. Moreover, identifying these reasons will help highlight some features of moral decisions in non‐ideal situations, which in turn might be relevant to some other moral or policy choices.     

Fix and sample with rats in the dynamics of choice

The generality of the molar view of behavior was extended to the study of choice with rats, showing the usefulness of studying order at various levels of extendedness. Rats' presses on two levers produced food according to concurrent variable-interval variable-interval schedules. Seven different reinforcer ratios were arranged within each session, without cues identifying them, and separated by blackouts. To alternate between levers, rats pressed on a third changeover lever. Choice changed rapidly with changes in component reinforcer ratio, and more presses occurred on the lever with the higher reinforcer rate. With continuing reinforcers, choice shifted progressively in the direction of the reinforced lever, but shifted more slowly with each new reinforcer. Sensitivity to reinforcer ratio, as estimated by the generalized matching law, reached an average of 0.9 and exceeded that documented in previous studies with pigeons. Visits to the more-reinforced lever preceded by a reinforcer from that lever increased in duration, while all visits to the less-reinforced lever decreased in duration. Thus, the rats' performances moved faster toward fix and sample than did pigeons' performances in previous studies. Analysis of the effects of sequences of reinforcer sources indicated that sequences of five to seven reinforcers might have sufficed for studying local effects of reinforcers with rats. This study supports the idea that reinforcer sequences control choice between reinforcers, pulses in preference, and visits following reinforcers.     

Syllables as processing units in handwriting production

This research focused on the syllable as a processing unit in handwriting. Participants wrote, in uppercase letters, words that had been visually presented. The interletter intervals provide information on the timing of motor production. In Experiment 1, French participants wrote words that shared the initial letters but had different syllable boundaries. In Experiment 2, French- and Spanish-speaking participants wrote cognates and pseudowords with a letter sequence that was always intrasyllabic in French and intersyllabic in Spanish. In Experiment 3, French-Spanish bilinguals wrote the cognates and pseudowords with the same type of sequences. In the 3 experiments, the critical interletter intervals were longer between syllables than within syllables, indicating that word syllable structure constrains motor production both in French and Spanish.     

The cumulative semantic cost does not reflect lexical selection by competition

The cumulative semantic cost describes a phenomenon in which picture naming latencies increase monotonically with each additional within-category item that is named in a sequence of pictures. Here we test whether the cumulative semantic cost requires the assumption of lexical selection by competition. In Experiment 1 participants named a sequence of pictures, while in Experiment 2 participants named words instead of pictures, preceded by a gender marked determiner. We replicate the basic cumulative semantic cost with pictures (Exp. 1) and show that there is no cumulative semantic cost for word targets (Exp. 2). This pattern was replicated in Experiment 3 in which pictures and words were named along with their gender marked definite determiner, and were intermingled within the same experimental design. In addition, Experiment 3 showed that while picture naming induces a cumulative semantic cost for subsequently named words, word naming does not induce a cumulative semantic cost for subsequently named pictures. These findings suggest that the cumulative semantic cost arises prior to lexical selection and that the effect arises due to incremental changes to the connection weights between semantic and lexical representations.