Perception of Genuine and Masking Smiles in Children and Adults: Sensitivity to Traces of Anger

The authors examined children's and adults' sensitivity to traces of anger in masking smiles by presenting participants with short video excerpts of smiles that differed by the intensity of an anger component. Fifty-two children, aged 6 to 12 years, and 26 adults were asked to judge whether a stimulus person was really happy or pretending to be happy. Six- and 7-year-old children were found to be sensitive to traces of anger, but less so than older children and adults. Researchers found evidence of explicit knowledge of the emotion hidden in masking smiles only in adult participants.     

Compensatory Effects of Cognitive Characteristics of the Source,the Message,and the Receiver Upon Attitude Change

This study explored the interactive effects of four cognitive variables (perceived expertise of the source, recipients' initial attitudes, number of arguments, and message sidedness) on attitude change. A 2 × 2 × 2 factorial design was used (N = 236 Canadian students): Results showed a positive and significant main effect of initial attitude on attitude change and three significant compensatory effects of independent variables on attitude change: (a) two-sided messages were more persuasive with fewer arguments; conversely for one-sided messages; (b) high expertise compensated for low number of arguments and conversely; and (c) higher expertise was more persuasive in the case of unfavorable recipients and conversely. Results also showed that when the message was one-sided and the number of arguments was large, low expertise was more persuasive than high expertise on initially opposed recipients, which confirms the cognitive response.     

Visual–spatial attention aids the maintenance of object representations in visual working memory

Theories have proposed that the maintenance of object representations in visual working memory is aided by a spatial rehearsal mechanism. In this study, we used two different approaches to test the hypothesis that overt and covert visual–spatial attention mechanisms contribute to the maintenance of object representations in visual working memory. First, we tracked observers’ eye movements while they remembered a variable number of objects during change-detection tasks. We observed that during the blank retention interval, participants spontaneously shifted gaze to the locations that the objects had occupied in the memory array. Next, we hypothesized that if attention mechanisms contribute to the maintenance of object representations, then drawing attention away from the object locations during the retention interval should impair object memory during these change-detection tasks. Supporting this prediction, we found that attending to the fixation point in anticipation of a brief probe stimulus during the retention interval reduced change-detection accuracy, even on the trials in which no probe occurred. These findings support models of working memory in which visual–spatial selection mechanisms contribute to the maintenance of object representations.     

Non‐symbolic halving in an Amazonian indigene group

Much research supports the existence of an Approximate Number System (ANS) that is recruited by infants, children, adults, and non‐human animals to generate coarse, non‐symbolic representations of number. This system supports simple arithmetic operations such as addition, subtraction, and ordering of amounts. The current study tests whether an intuition of a more complex calculation, division, exists in an indigene group in the Amazon, the Mundurucu, whose language includes no words for large numbers. Mundurucu children were presented with a video event depicting a division transformation of halving, in which pairs of objects turned into single objects, reducing the array's numerical magnitude. Then they were tested on their ability to calculate the outcome of this division transformation with other large‐number arrays. The Mundurucu children effected this transformation even when non‐numerical variables were controlled, performed above chance levels on the very first set of test trials, and exhibited performance similar to urban children who had access to precise number words and a surrounding symbolic culture. We conclude that a halving calculation is part of the suite of intuitive operations supported by the ANS.     

Aging and the Deletion Function of Inhibition

The present study was adapted from the sentence completion task of Hartman and Hasher (1991). We addressed the question raised by Burke (1997): are the age-related differences in priming effects found in that task better explained by deficits in explicit memory or by inefficient inhibitory mechanisms? In the study phase, older and younger adults read high cloze sentences ending with an expected or an unexpected final word. In the second phase, participants were asked to complete sentence frames with either the final word presented during the study phase (inclusion condition) or with another, new word (exclusion condition). The third phase was an indirect memory test of perceptual identification. Finally, we compared explicit memory for recalled and inhibited words in a recognition test. In perceptual identification by older adults, priming was equivalent for recalled and inhibited words, whereas in younger adults priming was higher for recalled than for inhibited words. In the explicit memory test, recognition scores were lower for inhibited words in both age groups. These results are consistent with the view of Hasher and Zacks (1988), who assume an age-related decline in the ability to suppress no-longer-relevant information     

Procedural vs. direct retrieval strategies in arithmetic: A comparison between additive and multiplicative problem solving

The opposition between declarative and procedural knowledge is used to account for the solution by more or less expert and novice arithmeticians of simple additions and multiplications presented either in mixed blocks (Experiments 1 and 3) or unmixed blocks (Experiment 2) in an equation verification task. In the three experiments, presenting the sign (+ vs 2) before the operands had a stronger effect in additions than in multiplications. This priming effect indicates that many participants use a counting procedure for additions that coexists with the declarative knowledge stored in the associative network. In contrast, the small size (and sometimes the absence) of a priming effect for the ''x'' sign, together with the weak effect of size and the frequency of interaction effects, reveals the essentially declarative nature of multiplication solution.     

Stimulus–response translation in manual and vocal modality: Is age‐related slowing influenced by changes in working memory functioning?

In some conditions, age‐related slowing rates are higher for manual than for vocal responses. The interaction between age and response modality was examined in four experiments in which the performance of younger (M = 22.6 years) and older (M = 70.8 years) adults was compared under various stimulus–response mapping rules. The interaction effect was not observed in a simple localisation task on which the manual modality had an advantage in both age groups (Experiment 1). When congruence between stimulus and response was reduced (Experiment 2), manual responses were disproportionately slowed in older participants. In conceptual and size comparison tasks (Experiment 3), the age‐by‐modality effect was not influenced by working memory load during the interval between the first and the second stimulus presentation. In an identification task, age‐related slowing effects were less when responses were spoken names than when nonwords were used as labels (Experiment 4). These results indicate that older participants experience a specific difficulty in activating arbitrary S–R mapping rules during executive control.     

Perceptuomotor Compatibility in Pursuit Tracking of Two-Dimensional Movements

In a previous article, we reported an investigation of visuomanual pursuit tracking of unpredictable two-dimensional targets. This article extends the study to the tracking of predictable stimuli. In both investigations, the target trajectory was elliptical. The experimental factors we varied were the orientation of the major axis of the ellipses (horizontal or vertical), the period of the movement (9.65 to 1.61 s), and the law of motion (natural vs. transformed). In the natural condition (L), the motion results from the combination of harmonic functions, as would be the case if the target were generated by a human. In the transformed (T) condition, the law of motion departs systematically from this natural model. The main results of the study are as follows: (a) Satisfactory performance is achieved only in the natural condition. Pursuit movements obey the same constraints observed in spontaneous movements. (b) Predictability affects significantly the average delay between target and pursuit. (c) Each component of the pursuit movements depends on both components of the targets. Thus, two-dimensional tracking generalizes significantly the classical one-dimensional condition. (d) The simple model developed previously to describe performance with unpredictable targets can be generalized to cover the present case as well.