Yoko Ishigami

Is a hands-free phone safer than a handheld phone?

INTRODUCTION Although it is becoming more and more accepted that driving while talking on a cell phone can be hazardous, most jurisdictions are making handheld phone use illegal while allowing hands-free phone use. METHODS The scientific literature exploring the effects of these two types of cell phone use on driving and driving-related performance is reviewed here. RESULTS Our review shows that talking on the phone, regardless of phone type, has negative impacts on performance especially in detecting and identifying events. Performance while using a hands-free phone was rarely found to be better than when using a handheld phone. Some studies found that drivers compensate for the deleterious effects of cell phone use when using a handheld phone but neglect to do so when using a hands-free phone. IMPACT ON INDUSTRY Current research does not support the decision to allow hands-free phone use while driving.

Repeated measurement of the components of attention using two versions of the Attention Network Test (ANT): stability, isolability, robustness, and reliability.

Using orthogonal subtractions of performance in selected conditions the attentional network test (ANT) measures the efficacy of three isolable components of attention: alerting, orienting, and executive control. Ten test sessions, each containing two versions of the ANT (Fan et al., 2002; Callejas et al., 2005), were administered to 10 young adults to examine stability, isolability, robustness, and reliability of the tests. Participants indicated the direction of a target arrow presented either above or below the fixation. The target arrow was accompanied by distracting arrows, either pointing to the same direction (congruent) as or the opposite direction (incongruent) to the target arrow. The arrows were preceded by informative visual cues (central, double, spatial, and no cue) differing in temporal and spatial information (Fan et al.) or by alerting auditory signals (tone and no tone) and uninformative visual cues (valid, invalid, and no cue) (Callejas et al.). All network scores remained highly significant even after nine previous sessions despite some practice effects in the executive and the orienting networks. Some lack of independence among the networks was found. The relatively poor reliability of network scores with one session of data rises to respectable levels as more data is added.

Are Individual Differences in Absentmindedness Correlated with Individual Differences in Attention

We administered the Cognitive Failures Questionnaire (CFQ) and one of two versions of the Attention Network Test (ANT) to 200 participants. Orthogonal subtraction scores based on performance (reaction time and error rate) from selected conditions of the ANT provided measures of the efficacy of three attention components: alerting, orienting, and executive control, while the total CFQ score provided a global measure of absentmindedness. Executive control was not associated with the CFQ in either experiment. When alertness was generated by a warning tone, greater alerting effects in reaction time were associated with higher CFQ scores (greater absentmindedness). The orienting effects in accuracy obtained from the two versions of the ANT varied with absentmindedness in opposite directions, suggesting that these two tests tap different aspects of orienting.

Repeated Measurement of the Components of Attention of Older Adults using the Two Versions of the Attention Network Test: Stability, Isolability, Robustness, and Reliability

Ishigami and Klein (2010) showed that scores of the three attention networks (alerting, orienting, and executive control) measured with the two versions of the Attention Network Test (ANT; Fan et al., 2002; Callejas et al., 2005) were robust over 10 sessions of repeated testing even though practice effects were consistently observed especially in the executive network when young adults were tested. The current study replicated their method to examine robustness, stability, reliability, and isolability of the networks scores when older adults were tested with these ANTs. Ten test sessions, each containing two versions of the ANT, were administered to 10 older adults. Participants were asked to indicate the direction of a target arrow, flanked by distractors, presented either above or below the fixation following auditory signals or/and visual cue. Network scores were calculated using orthogonal subtractions of performance in selected conditions. All network scores remained highly significant even after nine previous sessions despite some practice effects in the executive and the alerting networks. Some lack of independence among the networks was found. The relatively poor reliability of network scores with one session of data rises to respectable levels as more data is added.

Repeated measurement of the attention components of patients with multiple sclerosis using the Attention Network Test-Interaction (ANT-I): Stability, isolability, robustness, and reliability

The Attention Network Test (ANT) assesses the networks of attention (alerting, orienting, and executive control). The utility of measuring attention network performances with the repeated administration of the ANT in clinical populations has not yet been explored. In the present study, we administered a variant of the ANT (ANT-I) to 11 multiple sclerosis (MS) patients and 11 controls over six monthly sessions to examine the stability, isolability, robustness, and reliability of the ANT-I. Participants responded through button presses to indicate the direction of a target arrow presented either above or below a fixation cross. The target was accompanied by distracting arrows, pointing either in the same or opposite direction of the target arrow. Target arrows were preceded in some trials by alerting auditory signals and/or by uninformative visual cues. Network scores were calculated using orthogonal subtractions of performance under selected conditions. The MS patients were slower than the controls, though group differences in network performance were rare. Even after five test sessions, the network scores remained stable, despite some practice effects that were the largest under conditions that tested the executive network. The reliabilities of the orienting and executive network effects were good in both groups and increased across sessions, especially with the MS patients. The alerting network was the least reliable, especially for MS patients, but it also became more reliable across sessions. The results suggest that the ANT-I can be used to measure the integrity of attention networks for MS patients in applications that require repeated testing.

Using brain potentials to understand prism adaptation: the error-related negativity and the P300

Prism adaptation (PA) is both a perceptual-motor learning task as well as a promising rehabilitation tool for visuo-spatial neglect (VSN)—a spatial attention disorder often experienced after stroke resulting in slowed and/or inaccurate motor responses to contralesional targets. During PA, individuals are exposed to prism-induced shifts of the visual-field while performing a visuo-guided reaching task. After adaptation, with goggles removed, visuomotor responding is shifted to the opposite direction of that initially induced by the prisms. This visuomotor aftereffect has been used to study visuomotor learning and adaptation and has been applied clinically to reduce VSN severity by improving motor responding to stimuli in contralesional (usually left-sided) space. In order to optimize PAs use for VSN patients, it is important to elucidate the neural and cognitive processes that alter visuomotor function during PA. In the present study, healthy young adults underwent PA while event-related potentials (ERPs) were recorded at the termination of each reach (screen-touch), then binned according to accuracy (hit vs. miss) and phase of exposure block (early, middle, late). Results show that two ERP components were evoked by screen-touch: an error-related negativity (ERN), and a P300. The ERN was consistently evoked on miss trials during adaptation, while the P300 amplitude was largest during the early phase of adaptation for both hit and miss trials. This study provides evidence of two neural signals sensitive to visual feedback during PA that may sub-serve changes in visuomotor responding. Prior ERP research suggests that the ERN reflects an error processing system in medial-frontal cortex, while the P300 is suggested to reflect a system for context updating and learning. Future research is needed to elucidate the role of these ERP components in improving visuomotor responses among individuals with VSN.

Exploring the modulation of attentional capture by attentional control settings using performance and illusory line motion

Modulation of attentional capture by attentional control settings was explored using performance and phenomenology. Trials began with four figure-8s presented above, below, left, and right of fixation. Any figure-8 (or none) brightened uninformatively (cue) before presentation of either a digit target (2 or 5 made from a figure-8 by deletion) calling for a speeded identification, or a line connecting adjacent figure-8s calling for a motion judgement. Such lines are seen drawn away from an adjacent cue. Digit targets appeared only on the horizontal or vertical axes, encouraging voluntary attention to two (target-relevant) of the four figure-8s. Whereas voluntary attention reduced attentional capture from cues at taskirrelevant locations (when lines were unlikely to be presented near the task-irrelevant locations), it had no effect on motion judgements, suggesting that cue-elicited exogenous attention affects perceptual arrival times while voluntary attention prioritizes locations for further processing without affecting arrival times.

Stability of intraindividual variability as a marker of neurologic dysfunction in relapsing remitting multiple sclerosis

Background: Impairments in information processing speed are common in multiple sclerosis (MS), with affected individuals demonstrating slower responses and more intraindividual variability (IIV) in their performance on timed tasks. Evidence suggesting that IIV provides novel information about cognitive deficits in MS is accumulating; however, little is known about the stability of IIV across multiple assessments. In this study, we investigated IIV in response speed in persons with MS across 6 monthly sessions using the Attention Network Test–Interaction (ANT-I). Method: Individuals with relatively mild relapsing remitting MS and healthy controls completed the ANT-I at 6 monthly intervals. Clinical assessments (Sessions 1 and 6) and conventional magnetic resonance imaging (MRI) studies (Sessions 1–6) were examined for individuals with MS. Results: The MS group’s clinical and neuroimaging measures were stable during the 6-month period. Individuals with MS were slower and more variable in reaction time performance on the ANT-I than were controls. Differences in IIV between groups were maintained across the 6 sessions, with IIV demonstrating less susceptibility to across-session practice effects than mean latency scores. Conclusions: IIV provides a stable measure of cognitive performance in mildly affected persons with MS who are clinically and radiologically stable. Further studies exploring its utility as a clinical outcome are warranted.

Effect of stimulus hemifield on free-field auditory saltation

Auditory saltation is the orderly misperception of the spatial location of repetitive click stimuli emitted from two successive locations when the inter-click intervals (ICIs) are sufficiently short. The clicks are perceived as originating not only from the actual source locations, but also from locations between them. In two tasks, the present experiment compared free-field auditory saltation for 90 degrees excursions centered in the frontal, rear, left and right acoustic hemifields, by measuring the ICI at which subjects report 50% illusion strength (subjective task) and the ICI at which subjects could not distinguish real motion from saltation (objective task). A comparison of the saltation illusion for excursions spanning the midline (i.e. for frontal or rear hemifields) with that for stimuli in the lateral hemifields (left or right) revealed that the illusion was weaker for the midline-straddling conditions (i.e. the illusion was restricted to shorter ICIs). This may reflect the contribution of two perceptual channels to the task in the midline conditions (as opposed to one in the lateral hemifield conditions), or the fact that the temporal dynamics of localization differ between the midline and lateral hemifield conditions. A subsidiary comparison of saltation supported in the left and right auditory hemifields, and therefore by the right and left auditory forebrains, revealed no difference.

Repeated Measurement of the Components of Attention With Young Children Using the Attention Network Test: Stability, Isolability, Robustness, and Reliability

The current study examined the robustness, stability, reliability, and isolability of the attention network scores (alerting, orienting, and executive control) when young children experienced repeated administrations of the child version of the Attention Network Test (ANT; Rueda et al., 2004). Ten test sessions of the ANT were administered to 12 young children. Participants were asked to indicate the direction of a target fish, flanked by distractors, presented either above or below the fixation cross following different types of visual cues. Network scores, reflecting alerting, orienting, and executive control, were calculated using orthogonal subtractions of performance in selected conditions. Only the alerting network scores remained highly significant across the 10 sessions. The executive network scores showed some practice effects. The reliability of the network scores remained poor regardless of the amount of data. Based on the results, use of the ANT is cautioned against in young children when repeated testing is required.