Visuospatial asymmetry in dual‐task performance after subacute stroke

Various authors have referred to an association between neglect and non‐spatial components of attention. It has been suggested that an increase in attentional load could exacerbate neglect symptoms and reveal subtle, well‐compensated neglect. In the present study, 21 RH and 22 LH subacute stroke patients and 20 controls performed a computerized single‐detection task (CVRT) and a dual task (CVRT‐D) combining the detection task with a driving simulation task. Omissions, reaction times (RTs) and RT asymmetries were analysed to investigate the influence of increasing attentional load on neglect symptoms. RT asymmetries were most pronounced in RH patients. Although a clear increase in RT asymmetries between CVRT and CVRT‐D was observed, the amount of increase did not differ between both patient groups. Within both patient groups, correlations between RT asymmetries and ipsilesional RTs as a measure of general attention were significant in the single task but not in the dual task, indicating that increased attentional load may result in different degrees of lateralized and general attentional problems. Half of the patients with neglect on the BIT (Behavioural Inattention Test) showed increased RT asymmetries from CVRT to CVRT‐D. Moreover, two LH and RH patients without neglect symptoms on the BIT and CVRT showed distinctively increased asymmetries in the CVRT‐D, fostering the idea of an emergence of subtle neglect under increased attentional load. Dual‐task performance may draw attention towards patients who, without obvious signs of neglect, may show visuospatial attention deficits in complex situations.     

Listener perceptions of stuttering across two presentation modes: a quantitative and qualitative approach

The purpose of this study was to compare participants' quantitative and qualitative judgments of various forms and frequencies of stuttering, during either audiovisual or audio-only presentation modes. A total of 64 participants voluntarily agreed to participate in the study. Each participant was randomly assigned and exposed to only one of the four conditions of varying stuttering severity levels. The assigned speech sample was presented to the participant in either the audiovisual or audio-only mode. After watching or listening to the sample, participants completed a six-item Likert scale and were asked four open-ended questions. Comments made by listeners were developed into positive and negative comments as well as sorted into five theme clusters. The data analyses revealed a number of non-significant differences across mean Likert scale ratings for the six statements and for the number of positive and negative comments between the two presentation modes. However, the results provided partial support for the notion that as the frequency of stuttering increases, listeners tend to make increasingly more negative comments about the speaker. Additionally, there were no clear differences in comments across the five theme clusters between the two presentation modes. The findings suggest that the type of presentation mode does not appear to affect listeners' perceptions of stuttering to the same extent that stuttering severity does. EDUCATIONAL OBJECTIVES: The reader will be able to: (1) describe how listeners perceive and react to various frequencies of stuttering; (2) explain how audiovisual versus audio-only samples impact listener perceptions of stuttering and (3) provide examples of the ways in which qualitative data can enhance the understanding of how listeners react to various levels of stuttering.     

Divided attention years after severe closed head injury: the effect of dependencies between the subtasks

Lesions of white matter which connects distant brain areas are characteristic for closed head injury (CHI). It was predicted that this impairs divided attention only if dependent subtasks are used which require communication between corresponding brain processes. Fourteen chronic severe CHI patients (mean age 42 years) and 14 healthy controls, matched on age, gender, and education, participated in an experiment on divided attention. A typical left hemisphere task and a typical right hemisphere task must be simultaneously performed in a condition where they are completely independent and in conditions with dependencies between the tasks. Only in the dependent conditions the CHI group showed poor divided attention performance.     

Response dependency and processing dependency of line orientation and position in a single-item task

The relation between the processing of line-orientation information and position information was studied in two single-item recognition experiments with percentage correct as the dependent variable. In Experiment 1 subjects had to name the position and the orientation of a small oriented line segment in an otherwise empty field. In Experiment 2 subjects had to indicate in addition whether a line segment had been presented or not. Both experiments showed that orientation responses and position responses are highly and positively correlated. Inconsistencies in the results of two equivalent signal-detection analyses in Experiment 2 are interpreted as indicating that in the present type of task subjects often have no information about the target and have to guess. It is concluded that in such a situation a high-threshold model (subjects respond correctly if adequate information is available, and otherwise guess) is best suited to describe the results. After an appropriate correction for guessing, no orientation processing without position processing was found.     

Effectiveness of online word of mouth on exposure to an Internet-delivered intervention

The use of online word of mouth (WOM) seems a promising strategy to motivate young people to visit Internet-delivered interventions. An Internet-delivered intervention aimed at changing implicit attitudes related to alcohol was used in two experiments to test effectiveness of e-mail invitations on a first visit to the intervention. The results of the first experiment (N = 196) showed that an invitation by e-mail from a friend was more effective to attract young adults (aged 18–24 years) to the intervention website than an invitation from an institution. A 2 × 2 design was used in the second experiment (N = 236) to test manipulations of argument strength and the use of peripheral cues in invitations. Results showed that weak arguments were more effective to attract young adults to the intervention website when an incentive was withheld. These results need to be taken into account when using online WOM as a strategy to improve exposure to Internet-delivered interventions.     

Perception of acceleration with short presentation times: can acceleration be used in interception?

To investigate whether visual judgments of acceleration could be used for intercepting moving targets, we determined how well subjects can detect acceleration when the presentation time is short. In a differential judgment task, two dots were presented successively. One dot accelerated and the other decelerated. Subjects had to indicate which of the two accelerated. In an absolute judgment task, subjects had to adjust the motion of a dot so that it appeared to move at a constant velocity. The results for the two tasks were similar. For most subjects, we could determine a detection threshold even when the presentation time was only 300 msec. However, an analysis of these thresholds suggests that subjects did not detect the acceleration itself but that they detected that a target had accelerated on the basis of the change in velocity between the beginning and the end of the presentation. A change of about 25% was needed to detect acceleration with reasonable confidence. Perhaps the simplest use of acceleration for interception consists of distinguishing between acceleration and deceleration of the optic projection of an approaching ball to determine whether one has to run backward or forward to catch it. We examined the results of a real ball-catching task (Oudejans, Michaels, & Bakker, 1997) and found that subjects reacted before acceleration could have been detected. We conclude that acceleration is not used in this simple manner to intercept moving targets.     

Predictors for re-employment success in newly unemployed: A prospective cohort study

The aim of the present study was to examine which personal and situational factors affect reemployment success in persons in their first year of unemployment. In a prospective cohort study with a one-year follow-up, we investigated a sample of 3618 subjects who became unemployed. A survey was sent to all participants, including personal and situational factors, based on Wanberg's model, the Theory of Planned Behavior model and the Valence–Instrumentality–Expectancy model. Our results showed that ten key-factors predicted re-employment success in the first year after becoming unemployed. Knowing these factors, and in particular those which are amenable to change through any intervention program, may help to develop effective intervention strategies for those who facilitate reemployment in order to shorten the duration of unemployment.