Does temporal contiguity moderate contingency learning in a speeded performance task?

In four experiments, we varied the time between the onset of distracting nonwords and target colour words in a word–word version of the colour–word contingency learning paradigm. Contingencies were created by pairing a distractor nonword more often with one target colour word than with other colour words. A contingency effect corresponds to faster responses to the target colour word on high-contingency trials (i.e., distractor nonword followed by the target colour word with which it appears most often) than on low-contingency trials (i.e., distractor nonword followed by a target colour word with which it appears only occasionally). Roughly equivalent-sized contingency effects were found at stimulus-onset asynchronies (SOAs) of 50, 250, and 450 ms in Experiment 1, and 50, 500, and 1,000 ms in Experiment 2. In Experiment 3, a contingency effect was observed at SOAs of –50, –200, and –350 ms. In Experiment 4, interstimulus interval (ISI) was varied along with SOA, and learning was equivalent for 200-, 700-, and 1,200-ms SOAs. Together, these experiments suggest that the distracting stimulus does not need to be presented in close temporal contiguity with the response to induce learning. Relations to past research on causal judgement and implications for further contingency learning research are discussed.     

The Relationship Between Measures of Cognitive Attention and Behavioral Ratings of Attention in Typically Developing Children

In the present study, we explored the relation between performance on cognitive measures of attention (selection, sustained, and control) and behavioral ratings of inattention and hyperactivity in a sample of typically developing children aged 3 to 7 years. We also examined the influence of chronological age and IQ on both task performance and behavior ratings. Four well-documented attention paradigms were employed, the Visearch (single-target search) task as a measure of selective attention, the Continuous Performance Test (CPT) as a measure of sustained attention, the Day-Night task as a measure of response inhibition, and the Visearch (dual-target search) task as a measure of inhibitory control. The Conners' Rating Scales (Cognitive/Inattention and Hyperactivity subscales) were used to allow for a finer tuned comparison of cognitive performance as related to inattentive behaviors versus hyperactive behaviors. Findings indicate that accuracy and speed in the Visearch dual search task were the most sensitive measures relating respectively to inattentive and hyperactive rated behaviors.     

Interstimulus Intervals and Sensory Modality Modulate the Impact of a Cognitive Task on Postural Control

The present literature not only reveals the use of a wide variety of cognitive tasks but variability in their interaction with postural control. The question then arises, as to, whether postural control is sensitive to specific features of a cognitive task. The present experiment assessed the impact of cognitive tasks with interstimulus intervals (ISI) of varied duration and sensory modality on postural control in young adults. Seventeen participants (23.71 ± 1.99 years old) were instructed to stand on a force platform while concurrently performing cognitive tasks with ISIs of two and 5 s. The tasks were presented both, auditorily and visually. The visual tasks consisted of counting the total occurrence of a single digit. The auditory tasks consisted of counting the total occurrence of a single letter. Performing the cognitive tasks with an ISI of 2 s resulted only in an increase in the anteroposterior mean power frequency. Presenting the tasks visually also significantly reduced area of 95% confidence ellipse and AP and mediolateral sway variability. These results may suggest that ISIs can modify postural performance by altering the allocation of attentional focus. Also, presenting tasks using a visual sensory modality appears to yield lower postural sway.     

Gait and reach-to-grasp movements are mutually modified when performed simultaneously

Typically, prehension and gait behaviors are studied separately. However, little is known about what changes occur in these motor skills when they are combined. We investigated and characterized motor performance during combined walking and prehension at different levels of difficulty of the prehension task. Fifteen right-handed young adults were invited to walk at their self-selected pace and grasp a dowel as they walked. They also grasped the dowel in a stationary condition (upright stance). We combined conditions with/without obstacles and stable/unstable base for dowel prehension. Modifications in gait and prehension were identified when they were combined, especially for the most difficult prehension conditions. The grasping task caused an adaptation in gait because the participants preferred to adopt a more conservative strategy of increasing their dynamic stability during the approach phase and when grasping the dowel. Walking changed the prehension movement by reducing the reaching movement time, peak wrist velocity, and peak grip aperture velocity. In addition, the peak grip aperture was affected by the presence of obstacles close to the dowel. The participants adjusted their gait during the approach phase to facilitate dowel prehension, and they controlled the hand position online to adjust its configuration based on the prehension conditions.     

The role of processes and contents in human memory: An item response theory approach

This study investigated the specificities and communalities of visuospatial and verbal memory contents, as well as short-term memory and working memory (STM and WM) processes with the use of Rasch models as an alternative to the previous studies based on the classical test theory. A sample of 547 undergraduate students executed four computerised tasks, each consisting of verbal-numeric WM, visuospatial WM, verbal-numeric STM, and visuospatial STM content. Confirmatory factor analyses indicated that visuospatial and verbal-numeric memory are distinct, but correlated variables. Findings also support a domain-general view of WM capacity distinct from domain-specific storage. With the use of Rasch models, our results confirm previous experimental, psychometric, and neuropsychological studies, highlighting that memory span tasks can be divided into separate subsystems for content and processes. This study also shows that better results are obtained when models with person parameter estimates (provided from Rasch models) are adopted, rather than summed raw scores.     

Truth table tasks: The relevance of irrelevant

Two types of truth table tasks are used investigating mental representations of conditionals: a possibilities-based and a truth-based one. In possibilities tasks, participants indicate whether a situation is possible or impossible according to the conditional rule. In truth tasks participants evaluate whether a situation makes the rule true or false, or is irrelevant with respect to the truth of the rule. Comparing the two-option version of the possibilities task with the truth task in Experiment 1, the possibilities task yields logical answer patterns whereas the truth task yields defective patterns. Adding the irrelevant option to the possibilities task in Experiment 2 leads to a considerable amount of defective patterns in the possibilities task, but still to more logical patterns in the possibilities task than in the truth task. Experiment 3 shows that directionality matters since rule-to-situation tasks yield more logical answer patterns than do situation-to-rule tasks. We conclude that both task types are not comparable as such since wording, number of options and directionality influence the results.     

The Spiritual Dimension of Caring: Applying a Model for Spiritual Tasks of Ageing

SUMMARY

This chapter describes a spiritual dimension of ageing using themes and a model for spiritual tasks of ageing, developed as a part of doctoral studies that examined spirituality amongst a group of independent-living older adults in Canberra and NSW. This model has been tested further and the model was confirmed through in-depth interviews of residents of nursing homes in the ACT. The first study identified six major spiritual themes from participant interviews. These were: ultimate meaning in life for each person, the way they responded to meaning, self-sufficiency versus despair, moving from provisional to final life meanings, relationship versus isolation in ageing and hope versus despair.     

Cognitive control acts locally

Cognitive control adjusts information processing to momentary needs and task requirements. We investigated conflict adaptation when participants are performing two tasks, a Simon task and a SNARC task. The results indicated that one congruency effect (e.g., Simon) was reduced after conflict in the other task (e.g., SNARC), but only when both tasks used identical relevant information. On the other hand, when both tasks used different relevant information, a larger congruency effect was observed after conflict in the other task. The results are explained in terms of a local control mechanism.     

Being distinctive versus being conspicuous: The effects of numeric status and sex-stereotyped tasks on individual performance in groups

Being in the numeric minority (e.g., being a solo woman in a group of men) influences how well a person performs within a work group. But being the solo member is only one way in which people can be atypical in a group; a person can also represent a social or demographic category that has not typically been associated with the task that the group is working on. Using a design with four categories of group composition (minority, balanced, majority, homogeneous) and two categories of tasks (sex-typical, sex-atypical) we found that the sex composition of the group interacted with the sex typicality of the task to influence both positive deferrals by group members and individual performance in groups. But, rather than consistently reducing performance as prior research has suggested, being numerically atypical enhanced individual performance when the task was typical for that person’s sex. Further, positive deferrals mediated between the interaction of numeric composition and task typicality in influencing individual performance suggesting that both majority group members and the solo member affect one another’s performance in groups. We conclude by discussing why understanding the interplay between these two sources of stereotyping, numeric composition and task typicality, is important for understanding the social nature of individual performance in groups.