Bobby Nguyen

Texting while driving: Is speech-based text entry less risky than handheld text entry?

Research indicates that using a cell phone to talk or text while maneuvering a vehicle impairs driving performance. However, few published studies directly compare the distracting effects of texting using a hands-free (i.e., speech-based interface) versus handheld cell phone, which is an important issue for legislation, automotive interface design and driving safety training. This study compared the effect of speech-based versus handheld text entries on simulated driving performance by asking participants to perform a car following task while controlling the duration of a secondary text-entry task. Results showed that both speech-based and handheld text entries impaired driving performance relative to the drive-only condition by causing more variation in speed and lane position. Handheld text entry also increased the brake response time and increased variation in headway distance. Text entry using a speech-based cell phone was less detrimental to driving performance than handheld text entry. Nevertheless, the speech-based text entry task still significantly impaired driving compared to the drive-only condition. These results suggest that speech-based text entry disrupts driving, but reduces the level of performance interference compared to text entry with a handheld device. In addition, the difference in the distraction effect caused by speech-based and handheld text entry is not simply due to the difference in task duration.

Texting while driving: is speech-based texting less risky than handheld texting?

Research indicates that using a cell phone to talk or text while maneuvering a vehicle impairs driving performance. However, few published studies directly compare the distracting effects of texting using a hands-free (i.e., speech-based interface) versus handheld cell phone, which is an important issue for legislation, automotive interface design and driving safety training. This study compared the effect of speech-based versus handheld texting on simulated driving performance by asking participants to perform a car following task while controlling the duration of a secondary texting task. Results showed that both speech-based and handheld texting impaired driving performance relative to the drive-only condition by causing more variation in speed and lane position. Handheld texting also increased the brake response time and increased variation in headway distance. Texting using a speech-based cell phone was less detrimental to driving performance than handheld texting. Nevertheless, the speech-based texting task still significantly impaired driving compared to the drive-only condition. These results suggest that speech-based interaction disrupts driving, but reduces the levels of performance interference compared to handheld devices. In addition, the difference in the distraction effect caused by speech-based and handheld texting is not simply due to the difference in task duration.

Examination of Dual vs. Single Monitor Use during Common Office Tasks

Previous studies have found that using multiple monitors increases productivity, but there are also documented drawbacks to increased monitor count and/or size. The purpose of this study was to determine whether increases in productivity hold true with newer technology, like wide flat-screens, in the multitasking context. Sixty participants were asked to complete several tasks commonly completed in an office environment. These tasks were performed on four different monitor configurations: a single and dual 17” monitor(s) and single and dual 22” monitor(s). Participants located information from several documents and compiled this information into a new document. Dependent variables measured included efficiency, effectiveness, and satisfaction. Results indicated a performance benefit for dual monitor usage, regardless of monitor size. Participants most preferred using dual 22” monitors and least preferred a single 17” monitor.

Age-related difference in steering control under reduced visibility conditions

The current study investigated age-related differences in a steering control task under low visibility conditions. Younger and older drivers were presented with displays simulating forward vehicle motion through a 3D scene of random dots on a ground plane. The lateral position of the vehicle was perturbed by a simulated side wind gust according to a sum of sinusoidal functions. The drivers’ task was to steer the vehicle to maintain a straight path. The visibility of the driving scene was reduced by reducing the quantity and the quality of the optical flow field. We found that performance decreased when visibility was reduced for both older and younger drivers, with better performance for younger drivers as compared with older drivers. An age-related interaction was also found with deteriorated optical flow information. These results suggest that under reduced visibility conditions, older drivers may have increased accident risks due to decreased ability to successfully steer the vehicle. Published by Elsevier B.V.

Predicting Steering Control Performance from Coherent Motion Performance.

Integrating visual information spatially and temporally is important in motion perception and in many daily activities, such as steering in a driving task. Our recent research showed that reduced optic flow quality and quantity impaired steering performance under reduced visibility conditions. However, it is not clear how spatial and temporal integration of visual information is related to steering control under low visibility conditions. In the current study we examined whether spatial and temporal integration performance on coherent motion tasks under low visibility could predict performance on a steering control task under low visibility for younger drivers. In the coherent motion task, displays consisted of either a 2D or 3D array of dots, in which a portion of the dots moved in a uniform direction (i.e., coherency) and the remaining dots moved in random directions (i.e., noise). Participants were asked to identify the perceived direction of the coherent dots (in 2D displays) or to identify the perceived moving direction of the viewer (in 3D displays). Dot density and dot lifetimes were manipulated while coherency threshold was measured using the best BEST procedure. In the steering control task, participants viewed a 3D array of moving random dots and were asked to respond to a sinusoidal perturbation to their lateral position, simulating a driving behavior. Forty participants performed the coherent motion task and the steering control task. We found that temporal and spatial integration of the stimuli, and not display type, affected performance on the coherent motion task. A structural equation model revealed that coherent motion performance accounted for nearly 30% of steering control performance. These results suggest that under reduced visibility conditions, temporal and spatial integration of visual information may play an important role in certain aspects of driving, such as steering control. Meeting abstract presented at VSS 2015.

Apple iPad Usage Trends by Students and Non-Students:

Since its release in April 2010, the Apple iPad has become the de facto tablet for consumers. Given the increasing popularity of the iPad as a consumer, educational, and work device, we were interested in how different groups of people use the iPad. More specifically, we were interested in how students and non-students use the iPad at work, school, and at play. One-hundred thirteen participants completed an online survey about iPad use. Results indicated students use the iPad more often for socializing, playing games, editing and posting photos, listening to audio, and taking pictures or videos. On the other hand, non-students use the iPad more often for reading the news, eBooks, and eMagazines.