Selective attention is a primary determinant of the relationship between working memory and general learning ability in outbred mice

A single factor (i.e., general intelligence) can account for much of an individuals' performance across a wide variety of cognitive tests. However, despite this factor's robustness, the underlying process is still a matter of debate. To address this question, we developed a novel battery of learning tasks to assess the general learning abilities (GLAs) of mice. Using this battery, we previously reported a strong relationship between GLA and a task designed to tax working memory capacity (i.e., resistance to competing demands). Here we further explored this relationship by investigating which aspects of working memory (storage or processing) best predict GLAs in mice. We found that a component of working memory, selective attention, correlated with GLA comparably to working memory capacity. However, this relationship was not found for two other components of working memory, short-term memory capacity and duration. These results provide further evidence that variations in aspects of working memory and executive functions covary with general cognitive abilities.     

Processing level and recognition: A search method for inducing alternative encodings of unrelated words

Twenty-four subjects viewed cards containing four words. In synonym orienting, half of the cards contained a synonym pair and half did not; in homophone orienting, half of the displays contained a homophone pair. The remaining two words in each display were used to index retention. During presentation of displays, subjects responded “yes” or “no” to indicate the presence or absence of a matching pair. Following presentation, a recognition test was administered. Half the items were tested early and half were tested late; within each test order, half the items appeared with context cues during testing and half appeared without. Results showed superior recognition (1) following semantic orienting, (2) for items tested early, (3) for items tested with context, and (4) for nonmatch displays requiring exhaustive item comparison. An Orienting by Test Cuing interaction showed that the presence of test cues improved recognition for homophone orienting items only. The interaction may have resulted from the lack of cuetarget associations and the reinstatement of the phonemic orienting set during the test.     

Choice in transition: A comparison of melioration and the kinetic model

Transition-state choice behavior of pigeons was examined in two experiments designed to test predictions of melioration and the kinetic model. Both experiments began with an initial training condition during which subjects were maintained on concurrent variable-interval schedules. In Experiment 1, subjects were then exposed to concurrent variable-ratio schedules, whereas in Experiment 2, subjects were then exposed to concurrent extinction. Contrary to the predictions of melioration, but consistent with the kinetic model, acquisition of preference on concurrent variable-ratio schedules followed a negatively accelerated logistic trajectory, and preference remained stable in concurrent extinction. Predictions made by the kinetic model concerning rates of switching between alternatives were also supported.     

The effects of auditory and visual distractors on children's performance in a short-term memory task

Five- and 8-year-old children's performance in a short-term memory task was assessed under two auditory and two visual distraction conditions, as well as with no extraneous stimuli present. Performance under distraction was found to be inferior to that under nondistraction, but the degree of difference was roughly the same at ages 5 and 8, indicating little developmental change in the effects of distraction over this age range. Other findings included differences in the effectiveness of the distractors used and evidence that the children adapted somewhat to the influence of extraneous stimulation.     

Reading your own lips: Common-coding theory and visual speech perception

Common-coding theory posits that (1) perceiving an action activates the same representations of motor plans that are activated by actually performing that action, and (2) because of individual differences in the ways that actions are performed, observing recordings of one’s own previous behavior activates motor plans to an even greater degree than does observing someone else’s behavior. We hypothesized that if observing oneself activates motor plans to a greater degree than does observing others, and if these activated plans contribute to perception, then people should be able to lipread silent video clips of their own previous utterances more accurately than they can lipread video clips of other talkers. As predicted, two groups of participants were able to lipread video clips of themselves, recorded more than two weeks earlier, significantly more accurately than video clips of others. These results suggest that visual input activates speech motor activity that links to word representations in the mental lexicon.     

REX

This article is based on personal experience, an experience of grief and now, years later, an understanding of its transformative power in one's life. It is a true story and began some 25 years ago. As those who have gone through grief themselves know, it never ceases, it only changes, moves through its own cycles and permeates one's life. It almost has a life of its own within one's daily tasks. Eventually, grief can become a subtle and profound force in the act of living that is no longer felt as loss but as gain. In this story, I wish to present the idea that the relationship between the grieved and the person who has died continues to evolve and grow after the death process.     

Big Five personality dimensions in Italian and Dutch adolescents: A cross-cultural comparison of mean-levels, sex differences, and associations with internalizing symptoms

In the present cross-national comparison, self-reported Big Five personality data on large samples of Dutch (N = 1521) and Italian (N = 1975) adolescents were employed. Results suggest that the personality of Dutch and Italian adolescents can be described by the same Big Five traits, but that these might have slightly different meanings to the Dutch and Italian adolescent respondents. Supplementary analyses uncovered that sex differences are largest among Italian adolescents. Further comparisons reveal subtle cross-national differences in personality-psychopathology relationships, with stronger associations of Emotional Stability with depression for Italian when compared to Dutch adolescents. Results underscore that cross-national comparisons of personality may be alluring to use in research, however the findings of these comparisons should be interpreted with caution.     

The structure of working memory abilities across the adult life span

The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different for different age groups. Adults, ages 20-89 (n = 388), performed three simple and three complex verbal span tasks and three simple and three complex spatial memory tasks. Performance on the spatial tasks decreased at faster rates as a function of age than performance on the verbal tasks, but within each domain, performance on complex and simple span tasks decreased at the same rates. Confirmatory factor analyses revealed that domain-differentiated models yielded better fits than models involving domain-general constructs, providing further evidence of the need to distinguish verbal and spatial working memory abilities. Regardless of which domain-differentiated model was examined, and despite the faster rates of decrease in the spatial domain, age group comparisons revealed that the factor structure of working memory abilities was highly similar in younger and older adults and showed no evidence of age-related dedifferentiation.