Attentional and anatomical considerations for the representation of simple stimuli in visual short-term memory: evidence from human electrophysiology

Observers encoded the spatial arrangement of two or three horizontal line segments relative to a square frame presented for 150 ms either in left or right visual field and either above or below the horizontal midline. The target pattern was selected on the basis of colour (red vs. green) from an equivalent distractor pattern in the opposite left–right visual hemifield. After a retention interval of 450 or 650 ms a test pattern was presented at fixation. The task was to decide whether the test was the same as the encoded pattern or different. Selection of the to-be-memorised pattern produced an N2pc response that was not influenced by the number of line segments nor by the length of the retention interval, but that was smaller in amplitude for patterns presented in the upper visual field compared with patterns presented in the lower visual field. A sustained posterior contralateral negativity (SPCN) followed the N2pc. The SPCN was larger for patterns with three line segments than for two, was larger for patterns encoded from lower visual field than from upper visual field, and returned to baseline sooner for the shorter retention interval than for the longer interval. These results, and others, provide an interesting and complex pattern of similarities and differences between the N2pc and SPCN, consistent with the view that N2pc reflects mechanisms of attentional selection whereas the SPCN reflects maintenance in visual short-term memory.     

Influence of proficiency level and constraints on viewpoint switching: a study in web design

Web design is a complex problem in which designers have to consider the user's and the client's viewpoints to make satisfactory websites. Designers, particularly proficient ones, tend to privilege to the client's viewpoint to the detriment of the users' one. Consequently, websites often contain many usability violations and do not fit users' cognitive capacities, hence hampering navigation. The usability quality of websites may be proportional to designers' ability to switch between the client's and the user's viewpoints, which in turn may be influenced by designers' proficiency level. To explore the role of viewpoint switching in web design, performance was compared across three conditions emphasizing either the client's viewpoint, that of the user, or none of them in order to promote or hamper viewpoint switching. This manipulation had a significant effect on proficient designers' performance. Moreover, a significant relation between viewpoint switching and the usability quality of e‐mock‐ups was found. Copyright © 2008 John Wiley & Sons, Ltd.     

Data-driven Processing and Priming Effects in a Word-fragment Completion Task

An experiment was designed to examine the role and importance of data-driven processing in an implicit memory task: Word-fragment completion. We investigated the effects of priming and manipulating the context in which the target words had been read. Three main results emerged. First, replicating MacLeod's experiment (1989), we found that there was a very small priming effect for words previously studied in a text. Second, the magnitude of the priming effect increased with the perceptual difficulty of information intake during reading. Third, these variations in priming for the texts were functionally independent of subjects' recall of the text read. These results suggest that data-driven processing plays a critical role in priming. They are consistent with the transfer-appropriate processing theory recently advocated by Roediger, Weldon, and Challis (1989).     

Fluency versus conscious recollection in category-production performance: the performance of schizophrenic patients

The purpose of this study was to investigate the relative contribution in schizophrenics of automatic processes (fluency) and conscious processes (conscious recollection) for the control of preencoded material in category production tasks. In one condition (Exclusion condition), subjects were told specifically not to produce previously presented words during the category-production task. This condition was compared with a standard category-production task in which subjects were told to produce the six first words that came to mind for a semantic category (Inclusion condition). In the inclusion condition, the effects of conscious control and automatic processes operated in the same direction, whereas in the exclusion condition automatic influences and conscious control were opposed. A recognition task followed the category-production tasks. Since the exclusion condition required conscious control of encoded items, we hypothesized that schizophrenic patients would be less able than control subjects to avoid producing study list items. These results indicated that schizophrenics' performance differed from these of control subjects in the exclusion condition but not in inclusion condition. Recognition performance was similar in both the schizophrenic and the control groups. These results suggest a defective conscious control in schizophrenic patients and confirm the data from the literature on explicit memory in these patients.     

Sex differences in stipulated preferences and mate search by clients of a French marriage bureau

Using data from the file of a French matchmaking agency, this study confirmed some previous results on traditional male-female differences in stipulations by placers of advertisements: women seek features influencing financial resources, while men offer these characteristics and seek younger women. An interesting and original result is that the sampled women are older than the men, which partially explains why they spend relatively more money in professional matchmaking services as they age.     

Perception-action coupling and expertise in interceptive actions

The goal of this experiment was to show that expertise in interceptive actions can be explained by a shorter delay in movement regulation. In this contribution, we tested tennis experts and non-experts using a simulated interceptive task. The experimental device simulated linear motion of an object toward a target on a horizontal runway. Participants had to intercept the simulated moving object with their right hand holding a cart that could slide along a horizontal track perpendicular to the runway. Three different velocity conditions were used: a constant velocity condition that maintained the initial velocity (2m/s) constant until arriving on the target; the decelerated and accelerated velocity conditions, in which the velocity suddenly changed (400 ms before its arrival on the target) from 2 to 1m/s or 3m/s, respectively. Timing accuracy and movement correction after the unexpected velocity change were analysed. The experts were more accurate in the decelerative case (-29 and -124 ms respectively), in the accelerative case (69 and 116 ms respectively), but not in the constant velocity case (2 and 13 ms respectively). Findings can be explained by the shorter visuo-motor delay (VMD: the time required to adapt the movement to the new velocity) for the experts (162 ms) than for the non-experts (221 ms). This shorter VMD offers more time to adapt the interceptive movement to the new velocity. These results can be interpreted as an optimization of the perception-action coupling with expertise.     

When not teaming up puts parents at risk: Coparenting and parental burnout in dual-parent heterosexual families in Switzerland

Parental burnout refers to loss of energy and pleasure in the parental role. It is predictive of psychopathological outcomes in parents and dysfunctional parenting behaviors. Support of parental duties is central to alleviation of parental burden and prevention of burnout. Coparenting is the concept related to interparental mutual support in rearing a child. However, the links between coparenting and parental burnout have yet to be assessed. We thus aimed in this study to assess which dimensions of coparenting are linked with parental burnout. A total of 306 participants from the French-speaking part of Switzerland (120 fathers, 186 mothers) completed online questionnaires about parental burnout, their coparental relationship, and sociodemographic characteristics. We performed hierarchical regressions, entering sociodemographic characteristics in a first block and coparenting dimensions in a second block. Results showed that (i) a higher number of children and having younger children are linked to higher burnout; (ii) coparenting exposure to conflict is related to higher burnout, whereas endorsement of the partner's parenting is related to lower burnout; and (iii) no interaction effect occurs between sociodemographic characteristics and coparenting variables. Coparenting thus significantly contributes to the occurrence of burnout syndrome. Working on the coparental relationship preventively in parental educational programs or at a relational systemic level in therapy may help prevent burnout. Treating one parent only may not be sufficient to alleviate burnout, as negative coparenting could counter the effect of individual therapy.     

Perceptual and conceptual priming of individual words in coherent texts.

This study explores implicit memory within the domain of text processing. Three experiments were designed to study priming in word-fragment completion, word-stem completion, and free association tests following presentation of target words in the context of a coherent text. In order to examine the time course of perceptual and conceptual processes we investigated the priming effects by manipulating the perceptual context in which the target words had been read and the time given to the subjects for each test-cue. Three main results emerged. First, we found a significant priming effect in the three implicit tests for words previously studied in a text. Second, the magnitude of the priming effect only varied when the task demands required perceptual and conceptual processing, as was the case with the completion tests. Third, priming effects did not depend on subjects' comprehension of the text read. These results are discussed in the framework of the transfer-appropriate processing view proposed by Roediger, Weldon, and Challis (1989).     

Effects of Posttraining Intrahippocampal Injections of Platelet-Activating Factor and PAF Antagonists on Memory

The present experiments examined the effects of posttraining intrahippocampal injections of the degradative enzyme-resistant methylcarbamyl analog of the bioactive phospholipid platelet-activating factor (mc-PAF) and the platelet-activating factor (PAF) receptor antagonists BN52021 and BN 50730 on memory in male Long-Evans rats trained in a hidden platform version of the Morris water maze. Following an eight-trial training session, rats received a unilateral intrahippocampal injection of mc-PAF (0.5, 1.0, or 2.0 μg/0.5 μl), lyso-PAF (1.0 μg/0.5 μl), the cell surface PAF receptor antagonist BN 52021 (0.25, 0.5, or 1.0 μg/0.5 μl), the intracellular PAF receptor antagonist BN 50730 (2.0, 5.0, or 10.0 μg/0.5 μl), or vehicle (50% DMSO in 0.9% saline; 0.5 μl). On a retention test conducted 24 h after training, the escape latencies of rats administered mc-PAF (1.0 or 2.0 μg) were significantly lower than those of the vehicle-injected controls, demonstrating a memory-enhancing effect of mc-PAF. Injections of lyso-PAF, a structurally similar metabolite of PAF, had no influence on memory, indicating that the memory-enhancing effect of mc-PAF is not caused by membrane perturbation by the phospholipid. The retention test escape latencies of rats administered BN 52021 (0.5 μg) and BN 50730 (5.0 or 10 μg) were significantly higher than those of the controls, indicating a memory impairing effect of both PAF antagonists. When mc-PAF, BN 52021, or BN 50730 was administered 2 h posttraining, no effect on retention was observed, indicating a time-dependent effect of the neuroactive substances on memory storage. The findings suggest a role for endogenous PAF in hippocampal-dependent memory processes.