Human factors evaluation of an in-vehicle active traffic and demand management (ATDM) system

This research study focused on the evaluation of an emulated in-vehicle Active Traffic and Demand Management (ATDM) system on Interstate 66 in Northern Virginia. Traditional ATDM systems rely on infrastructure-mounted variable message signs (VMS) to provide information (speed limits, lane availability, etc.) to the traveling public. By providing information about dynamic roadway conditions on an in-vehicle device, the ATDM may improve driving safety and performance by allowing drivers to remain consistently aware of forthcoming traffic conditions and roadway requirements; even when external signage is inaccessible. This study represents an initial investigation of an emulated in-vehicle ATDM to provide developers with design guidance and ensure that unintended consequences, such as distraction, do not undermine the potential benefits.Twenty younger and 20 older participants, accompanied by a member of the research team, experienced the following ATDM features on an in-vehicle device (IVD) mounted to the dashboard: (1) dynamic speed limits, (2) dynamic lane use/shoulder control, (3) High Occupancy Vehicle (HOV) restrictions, and (4) roadway information from variable message signs. The IVD was equipped with auditory and visual alerts notifying the driver when relevant visual information was updated. Research questions addressed distraction and driver behavior associated with use of the system. Qualitative and quantitative participant data was acquired from the instrumented vehicle, various questionnaires, and researcher observation.Several key findings were uncovered: (1) The IVD, as tested, did not warrant classification as a source of distraction according to the NHTSA guidelines; v2) There was a significant difference in eye-glance durations to the IVD when comparing the VMS alerts to both the speed limit and lane management alerts; and (3) The speed limit alert motivated participants to alter their speed (per survey results and participant speed data).     

Practice effects on speech production planning: evidence from slips of the tongue in spontaneous vs. preplanned speech in Japanese

The present study addresses the question of how practice in expressing the content to be conveyed in a specific situation influences speech production planning processes. A comparison of slips of the tongue in Japanese collected from spontaneous everyday conversation and those collected from largely preplanned conversation in live-broadcast TV programs reveals that, although there are those aspects of speech production planning that are unaffected by practice, there are various practice effects, most of which can be explained in terms of automatization of the processing of content, resulting in shifts in the loci of errors.     

Effect of speech task on intelligibility in dysarthria: a case study of Parkinson's disease

This study assessed intelligibility in a dysarthric patient with Parkinson's disease (PD) across five speech production tasks: spontaneous speech, repetition, reading, repeated singing, and spontaneous singing, using the same phrases for all but spontaneous singing. The results show that this speaker was significantly less intelligible when speaking spontaneously than in the other tasks. Acoustic analysis suggested that relative intensity and word duration were not independently linked to intelligibility, but dysfluencies (from perceptual analysis) and articulatory/resonance patterns (from acoustic records) were related to intelligibility in predictable ways. These data indicate that speech production task may be an important variable to consider during the evaluation of dysarthria. As speech production efficiency was found to vary with task in a patient with Parkinson's disease, these results can be related to recent models of basal ganglia function in motor performance.     

Task-related factors in oral motor control: speech and oral diadochokinesis in dysarthria and apraxia of speech

This study was focused on the potential influence of task-related factors on oral motor performance in patients with speech disorders. Sentence production was compared with a nonspeech oral motor task, i.e., oral diadochokinesis. Perceptual and acoustic measures of speech impairment were used as dependent variables. Between-task comparisons were made for subsamples of a population of 140 patients with different motor speech syndromes, including apraxia of speech and cerebellar dysarthria. In a further analysis subgroups were matched for speaking rate. Overall, dysdiadochokinesis was correlated with the degree of speech impairment, but there was a strong interaction between task type and motor speech syndrome. In particular, cerebellar pathology affected DDK to a relatively greater extent than sentence production, while apraxic pathology spared the ability of repeating syllables at maximum speed.     

Perception of dynamic acoustic patterns by an individual with unilateral verbal auditory agnosia

Previous studies have found that subjects diagnosed with verbal auditory agnosia (VAA) from bilateral brain lesions may experience difficulties at the prephonemic level of acoustic processing. In this case study, we administered a series of speech and nonspeech discrimination tests to an individual with unilateral VAA as a result of left-temporal-lobe damage. The results indicated that the subject's ability to perceive steady-state acoustic stimuli was relatively intact but his ability to perceive dynamic stimuli was drastically reduced. We conclude that this particular aspect of acoustic processing may be a major contributing factor that disables speech perception in subjects with unilateral VAA.     

Gesture is at the cutting edge of early language development

Children who produce one word at a time often use gesture to supplement their speech, turning a single word into an utterance that conveys a sentence-like meaning ('eat'+point at cookie). Interestingly, the age at which children first produce supplementary gesture-speech combinations of this sort reliably predicts the age at which they first produce two-word utterances. Gesture thus serves as a signal that a child will soon be ready to begin producing multi-word sentences. The question is what happens next. Gesture could continue to expand a child's communicative repertoire over development, combining with words to convey increasingly complex ideas. Alternatively, after serving as an opening wedge into language, gesture could cease its role as a forerunner of linguistic change. We addressed this question in a sample of 40 typically developing children, each observed at 14, 18, and 22 months. The number of supplementary gesture-speech combinations the children produced increased significantly from 14 to 22 months. More importantly, the types of supplementary combinations the children produced changed over time and presaged changes in their speech. Children produced three distinct constructions across the two modalities several months before these same constructions appeared entirely within speech. Gesture thus continues to be at the cutting edge of early language development, providing stepping-stones to increasingly complex linguistic constructions.     

Audio-visual speech perception is special

In face-to-face conversation speech is perceived by ear and eye. We studied the prerequisites of audio-visual speech perception by using perceptually ambiguous sine wave replicas of natural speech as auditory stimuli. When the subjects were not aware that the auditory stimuli were speech, they showed only negligible integration of auditory and visual stimuli. When the same subjects learned to perceive the same auditory stimuli as speech, they integrated the auditory and visual stimuli in a similar manner as natural speech. These results demonstrate the existence of a multisensory speech-specific mode of perception.     

Infants' understanding of object-directed action

When and in what ways do infants recognize humans as intentional actors? An important aspect of this larger question concerns when infants recognize specific human actions (e.g. a reach) as object-directed (i.e. as acting toward goal-objects). In two studies using a visual habituation technique, 12-month-old infants were tested to assess their recognition that an adult's reach is directed toward its target object. Infants in the experimental condition were habituated to a display in which an actor reached over a wall-like barrier with an arcing arm movement, to pick up a ball. After habituation infants saw two test displays, for which the barrier was removed. In the direct test event the actor reached directly for the ball, the arm tracing a visually new path, but the action consistent with attempting to reach for the object as directly as possible. In the indirect test event the actor traced the old path, reaching over in an arc, even though the wall was no longer present. This arm movement was identical to that in habituation but no longer displayed a reach going directly to its object. In a control condition infants saw the same movements but in a situation with no goal-object. In the experimental conditions, with a goal object present, infants looked longer at the indirect test event in comparison to the direct test event. In the control conditions infants looked equally at both indirect and direct test events. We conclude that sensitivity to human object-directed action is established by 12-month-olds and compare these results to recent findings by [Gergely, G., Nadasdy, Z., Csibra, G., & Biro S. (1995). Taking the intentional stance at 12 months of age. Cognition, 56, 165-193] and [Woodward, A. (1998). Infants selectively encode the goal object of an actor's reach. Cognition, 69, 1-34].     

近五十年来台湾地区士林哲学之研究与前瞻

根据祁尔松（Etienne Gilson）的说法,中世纪哲学,尤其是十三世纪的思想,是基督宗教哲学。本文按其在台湾发展时所袭用的名词,称之为士林哲学。士林哲学之传入中国,虽然早在利玛窦时期（1550—1610）已经开始,但真正成为学术思想之主流之一,是最近五十年来在台湾地区的发展。20世纪初士林哲学初传入台湾时,当时的思想环境,对基督宗教哲学并不十分友善,这种种情况,与中世纪的思想家,面对信仰与神学之挑战相似。当时的思想家,融合各种不同的思想派系,对柏拉图与亚理斯多德的观念,重新诠释与批判,批判与诠释是创新的基础。所以,中世纪可说是哲学的第二春,而中世纪哲学之精华,即全盛期的士林哲学。十四世纪唯名论之后,士林哲学逐步式微,于十九世纪末再兴。本文认为,士林哲学在台湾发展之过程,与其在中世纪之盛行,及十九世纪末之再兴,背景虽异但有不少相似之处,而这些相似之处,正是士林哲学之基本思想与立场。本文对台湾士林哲学之发展,从四方面探讨：（1）回到形上学之根以面对新的挑战;（2）形上学基本立场与概念之说明;（3）反思与批判;（4）未来发展之方向。本文所参考之资料,一是已发表之学术文献;其二是与学者们之正式交谈——如学术演讲、座谈会等,及非正式之谈话、访问等。     

Muscular Activity in the Arm during Lexical Retrieval: Implications for Gesture-Speech Theories

The origin and functions of the hand and arm gestures that accompany speech production are poorly understood. It has been proposed that gestures facilitate lexical retrieval, but little is known about when retrieval is accompanied by gestural activity and how this activity is related to the semantics of the word to be retrieved. Electromyographic (EMG) activity of the dominant forearm was recorded during a retrieval task in which participants tried to identify target words from their definitions. EMG amplitudes were significantly greater for concrete than for abstract words. The relationship between EMG amplitude and other conceptual attributes of the target words was examined. EMG was positively related to a word’s judged spatiality, concreteness, drawability, and manipulability. The implications of these findings for theories of the relation between speech production and gesture are discussed.This experiment was done by the first author under the supervision of the second author in partial completion of the Ph.D. degree at Columbia University. We gratefully acknowledge the advice and comments of Lois Putnam, Robert Remez, James Magnuson, Michele Miozzo, and Robert B. Tallarico, and the assistance of Stephen Krieger, Lauren Walsh, Jennifer Kim, and Jillian White.