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.     

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.     

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.     

Trait emotional intelligence profiles of students from different university faculties

This study investigated the trait emotional intelligence (trait EI or trait emotional self‐efficacy) profiles of 512 students from five university faculties: technical studies, natural sciences, social sciences, arts, and humanities. Using the Trait Emotional Intelligence Questionnaire, it was hypothesised that (a) social sciences would score higher than technical studies in Emotionality, (b) arts would score higher than technical studies in Emotionality, (c) arts would score lower than technical studies in Self‐control, and (d) there would be an interaction between gender and faculty, whereby female students would score higher than male students within the social sciences only. Several other exploratory comparisons were also performed. Results supported hypotheses (a), (b), and (d), but not hypothesis (c), although the differences were in the predicted direction.     

The kinds of information that support novel associative object priming and how these differ from those that support item priming

We investigated how the information that supports novel associative and item object priming differs under identical study/test conditions. In Experiments 1 and 2, participants rated the meaningfulness of sentences linking two object pictures at study. At test, they performed either a size judgement or an associative recognition memory task on intact, recombined and novel picture (Experiment 1) or word (Experiment 2) associations. Associative priming was modulated by subjective meaningfulness of the encoded links, and depended on study/test perceptual overlap. In contrast, item priming was neither affected by the meaningfulness of the sentences nor by study/test changes in the stimulus presentation format. Associative priming and recognition were behaviourally dissociated, and associative recognition was probably too slow to have seriously contaminated associative priming. In Experiment 3, participants performed a perceptually oriented task during both experimental phases, and both associative and item priming were observed. These results suggest that associative priming depends on stored associative semantic and perceptual information when the test task requires flexible retrieval of associative information. Under the same conditions, item priming may only require activation of items' semantic properties. When both study and test tasks stress perceptual processing, retrieval of perceptual information is sufficient to support both kinds of priming.     

The mental representation of living and nonliving things: Differential weighting and interactivity of sensorial and non-sensorial features

Warrington and colleagues (Warrington & McCarthy, 1983, 1987; Warrington & Shallice, 1984) claimed that sensorial and functional-associative (FA) features are differentially important in determining the meaning of living things (LT) and nonliving things (NLT). The first aim of the present study was to evaluate this hypothesis through two different access tasks: feature generation (Experiment 1) and cued recall (Experiment 2). The results of both experiments provided consistent empirical support for Warrington and colleagues' assumption. The second aim of the present study was to test a new differential interactivity hypothesis that combines Warrington and colleagues' assumption with the notion of a higher number of intercorrelations and hence of a stronger connectivity between sensorial and non-sensorial features for LTs than for NLTs. This hypothesis was motivated by previous reports of an uncrossed interaction between domain (LTs vs NLTs) and attribute type (sensorial vs FA) in, for example, a feature verification task (Laws, Humber, Ramsey, & McCarthy, 1995): while FA attributes are verified faster than sensorial attributes for NLTs, no difference is observed for LTs. We replicated and generalised this finding using several feature verification tasks on both written words and pictures (Experiment 3), including in conditions aimed at minimising the intervention of priming biases and strategic or mnemonic processes (Experiment 4). The whole set of results suggests that both privileged relations between features and categories, and the differential importance of intercorrelations between features as a function of category, modulate access to semantic features.