Task-load manipulation in the Symbol Digit Modalities Test: An alternative measure of information processing speed

ObjectiveTo evaluate the utility of an oral fMRI-adapted version of the Symbol Digit Modalities Test (SDMT) to assess information processing speed (IPS) using three different interstimulus intervals (ISI).MethodsNineteen right-handed healthy controls performed the adapted version of the SDMT, consisting of a block design that had a total of 6 control/activation block pairs with 3 different ISIs (1.5, 2 and 2.5 s) presented in two different runs: in ascending and descending orders. The brain activation patterns during different ISIs were assessed by effective functional connectivity analysis based on independent component analysis.ResultsAs expected, all conditions yielded activations in the fronto-parietal networks (FPNs) related to attention processes. Shorter ISIs (1.5 and 2 s) not only yielded greater patterns of connectivity within fronto-parietal and occipital regions such as the FPN and fronto-occipital network (FON), but also recruited more functional networks overall. Task performance at the shortest ISI was negatively correlated with connectivity at the FPN and activity of the pre-supplementary motor area extending to the cingulate gyrus.ConclusionIncreasing IPS demands due to shorter ISIs resulted in an increased level and number of functional networks required, increased connectivity within the FPN and FON, and enhancement of the prefrontal cortex. IPS does not arise from activity of a single b area but from affective information transfer among distant cortical regions of the frontal and parietal cortices. This adapted version of the SDMT may be useful for studying alterations of IPS in clinical and nonclinical populations.     

Cycling: A benefit for health or just a means of transport? Case study Brno (Czech Republic) and its surroundings

Reducing pollution and preventing heavy traffic in cities together with recent transport policies are encouraging people to use more sustainable modes of transport, such as walking, cycling or public transport, in preference to private cars. The study was aimed at analysing general conditions for bicycle utilization, and their application to the outskirts of the largest Moravian town, Brno, and discussing the possible future of bicycling in this region, including its relation to health. What motivating factors could influence people’s decision to use bicycles as a means of transport? A survey was conducted at the third-largest university in Brno, where the respondents were approached. According to the obtained results, more than half of the respondents used bicycles mostly for leisure purposes. Nevertheless, almost one-third mentioned bicycling for transport purposes. Thus, there is a potential for cycling to become a significant part of transport and thus contribute to human health and a healthy city environment; however, the region should considerably adjust its infrastructure to encourage cyclists to visit Brno and its surroundings.     

Are we there yet? Trip duration and mood during travel

Are longer trips more strenuous or unpleasant than shorter ones? This paper examines this question using data from the American Time Use Survey’s well-being module, which queried individuals about the extent to which they felt happiness, pain, sadness, stress, and fatigue during three randomly selected daily activities. Over 22,000 instances of individuals traveling are observed, including their trip duration, mode, purpose, and demographic and geographic information. Each emotion, plus a constructed, composite mood variable, is regressed on trip duration. Overall, the relationship between trip duration and traveler mood is not strong, which is unsurprising given prior findings on the limited impact of activities on mood. However, there is a statistically significant and negative association between trip duration and mood, primarily because of rising stress, fatigue and sadness on long trips. This is particularly true for drivers, while negative emotions do not rise with increasing trip duration for auto passengers. This suggests strain rises as the result of operating the vehicle for long periods, not traveling in an auto per se. Long bicycle trips are more painful than shorter ones, probably due to the physical demands of the mode, and long train trips are associated with less sadness. For commutes, long trips significantly degrade the mood of both drivers and bus riders, in the latter case probably due in part to vehicle crowding and standing. The findings imply that reducing the duration of trips, for example through land use policies that reduce trip distances, or congestion reduction, would have emotional benefits. Policies to promote ridesharing instead of solo driving for long trips may increase traveler mood in the aggregate. Improving bus service or substituting rail for bus for long commute trips may also improve traveler mood.     

The long arm of time pressure at work: Cognitive failure and commuting near-accidents

This study tests whether cognitive failures mediate effects of work-related time pressure and time control on commuting accidents and near-accidents. Participants were 83 employees (56% female) who each commuted between their regular place of residence and place of work using vehicles. The Workplace Cognitive Failure Scale (WCFS) asked for the frequency of failure in memory function, failure in attention regulation, and failure in action execution. Time pressure and time control at work were assessed by the Instrument for Stress Oriented Task Analysis (ISTA). Commuting accidents in the last 12 months were reported by 10% of participants, and half of the sample reported commuting near-accidents in the last 4 weeks. Cognitive failure significantly mediated the influence of time pressure at work on near-accidents even when age, gender, neuroticism, conscientiousness, commuting duration, commuting distance, and time pressure during commuting were controlled for. Time control was negatively related to cognitive failure and neuroticism, but no association with commuting accidents or near-accidents was found. Time pressure at work is likely to increase cognitive load. Time pressure might, therefore, increase cognitive failures during work and also during commuting. Hence, time pressure at work can decrease commuting safety. The result suggests a reduction of time pressure at work should improve commuting safety.     

Spatial correspondence between onsets and offsets of stimuli and responses

The Simon effect denotes faster responses when the task-irrelevant stimulus position corresponds to response position than when it does not. A common explanation is that a spatial stimulus code is formed automatically and activates a spatially corresponding response code. Previous research on stimulus–response (S–R) compatibility has focused on the ability to initiate movements to stimulus onsets. The present study investigates spatial-compatibility effects (i.e., the Simon effect) in the ability to initiate and to terminate actions both to stimulus onsets and to stimulus offsets. There were four major results. Firstly, offset stimuli produced normal Simon effects suggesting that stimulus offsets can automatically produce spatial codes. Secondly, onset stimuli produced larger Simon effects than offset stimuli, which is consistent with the attention-shift account of spatial coding. Thirdly, Simon effects were also observed in action termination. Fourthly, Simon effects in action initiation and in action termination were of similar size.     

The role of input and output modality pairings in dual-task performance: evidence for content-dependent central interference

Recent debate regarding dual-task performance has focused on whether costs result from limitations in central capacity, and whether central operations can be performed in parallel. While these questions are controversial, the dominant models of dual-task performance share the assumption that central operations are generic--that is, their interactions are independent of stimulus and response modalities. To examine these issues, we conducted a series of dual-task experiments with different input and output modality pairings. One condition combined a visual-manual task with an auditory-vocal task, and the other condition reversed the input-output pairings, combining a visual-vocal task with an auditory-manual task. Input/output modality pairings proved to be a key factor; throughout practice, dual-task costs were generally more than twice as large with visual-vocal/auditory-manual tasks than with the opposite arrangement of modalities (Experiments 1 and 2). These differences could be explained neither by competition for peripheral resources nor by differences in single-task response times (Experiment 3). Moreover, the persistent dual-task costs did not appear to stem from a central bottleneck. Contrary to the dominant models of dual-task performance, we propose that central interference between tasks depends not just on the duration of central operations, nor just strategic adaptation, but also on the content of those operations. Implications for structural and strategic accounts of dual-task interference are discussed.     

Fluid intelligence is independently associated with all-cause mortality over 17 years in an elderly community sample: An investigation of potential mechanisms

The long-term relationship between lower intelligence and mortality risk in later life is well established, even when controlling for a range of health and sociodemographic measures. However, there is some evidence for differential effects in various domains of cognitive performance. Specifically, tests of fluid intelligence may have a stronger association with mortality than do tests of crystallized intelligence. The present study examines the relationship between intelligence and mortality in a sample of 896 Australian community-dwelling males and females, aged 70–97 at recruitment and followed for up to 17 years. There were 687 deaths during the follow-up period. Cox proportional hazard regression models examined whether the relationship between intelligence and mortality might be mediated by socioeconomic status, by health behaviors, by health status, or a combination of these. Higher fluid intelligence — as measured by the Symbol–Letter Modalities Test — was strongly associated with lower mortality rates (Hazard ratio = 0.80; 95% confidence interval = 0.72–0.88), even after accounting for any combination of potential mediators and confounders. A significant association between crystallized intelligence, as measured by the National Adult Reading Test, and mortality (HR = 0.89; 95% CI = 0.80–0.99) was attenuated by the inclusion of socioeconomic, health status measures, and health behavior measures and when deaths from the first four years of the study were excluded. The findings show little support for the hypothesized mechanisms of the intelligence–mortality relationship.     

Common sense about qualities and senses

There has been some recent optimism that addressing the question of how we distinguish sensory modalities will help us consider whether there are limits on a scientific understanding of perceptual states. For example, Block has suggested that the way we distinguish sensory modalities indicates that perceptual states have qualia which at least resist scientific characterization. At another extreme, Keeley argues that our common-sense way of distinguishing the senses in terms of qualitative properties is misguided, and offers a scientific eliminativism about common-sense modalities which avoids appeal to qualitative properties altogether. I’ll argue contrary to Keeley that qualitative properties are necessary for distinguishing senses, and contrary to Block that our common-sense distinction doesn’t indicate that perceptual states have qualia. A non-qualitative characterization of perceptual states isn’t needed to avoid the potential limit on scientific understanding imposed by qualia.

Would you rather teleport or spend some time commuting? Investigating individuals’ teleportation preferences

The “teleportation test” is a unique question—used in some travel behavior research since the 2000s—to examine individuals’ perceptions towards travel time and affinities for travel. It gives people a hypothetical choice between teleporting or spending some time traveling. All studies (using different methods, including focus groups, interviews, and questionnaires) have consistently reported high teleportation preferences (about 70%). Yet, few correlates of teleportation preferences (especially sociodemographic and perceptual characteristics) have been investigated. Using data from an online questionnaire of 648 commuters in Portland, Oregon, this study investigated factors affecting individuals’ teleportation preferences. While generally representative of the area’s commuters, the sample did have higher shares of high-income workers and people using active modes or transit. Overall, 62% of respondents preferred to teleport than to spend some time commuting. Results from binary logit models identified actual commute duration, typical mode of travel, and “ideal” travel time (but no demographic attributes) as major predictors of preferences to teleport. As expected, people with longer commute durations had a greater desire to teleport, whereas bicyclists and pedestrians more often preferred to commute. People with longer ideal travel times had a greater affinity to commute and were less keen to teleport. Analysis of follow-up questions exploring reasons for respondents’ answers suggested that most “teleporters” were motivated by saving time to do other things, while most “commuters” found parts of their commutes to be enjoyable or productive. Findings from this study are consistent with related studies in implying that a teleportation preference does not necessarily represent zero ideal travel time or viewing travel time as wasted. Finally, this study discusses several travel behavior policy implications of the teleportation test, along with limitations and areas for future research.