Spoken English discrimination (SED) training with multilingual Malaysians: effect of adaptive staircase procedure and background babble in high variability phonetic training.

High variability phonetic training (HVPT) has been shown to improve non-native speakers’ perceptual performance in discriminating difficult second language phonemic contrasts (Bradlow, Akahane-Yamada, Pisoni, & Tohkura, 1999; Bradlow, Pisoni, Akahane-Yamada, & Tohkura, 1997; Lively, Logan, & Pisoni, 1993; Lively, Pisoni, Yamada, Tohkura, & Yamada, 1994; Logan, Lively, & Pisoni, 1991). The perceptual learning can be generalized to novel words (Wang & Munro, 2004), novel speakers (Nishi & Kewley-Port, 2007; Richie & Kewley-Port, 2008) and even to speech production (Bradlow et al., 1997). However, the rigidity of the laboratory training settings has limited applications to real life situations. The current thesis examined the effectiveness of a new phonetic training program - the Spoken English Discrimination (SED) training. SED training is a computerized individual training program designed to improve non-native speakers’ bottom-up perceptual sensitivity to discriminate difficult second language (L2) phonemic contrasts. It combines a number of key training features including 1) natural spoken stimuli, 2) highly variable stimuli spoken by multiple speakers, 3) multi-talker babble as background noise and 4) an adaptive staircase procedure that individualizes the level of background babble. The first experiment investigated the potential benefits of different versions of the SED training program. The effect of stimulus variability (single speaker vs. multiple speakers) and design of background babble (constant vs. adaptive staircase) were examined using English voiceless-voiced plosives /t/-/d/ phonemic contrast as the training materials. No improvements were found in the identification accuracy on the /t/-/d/ contrast in post-test, but identification improvements were found on the untrained English /ε/-/æ/ phonemic contrast. The effectiveness of SED training was re-examined in Chapter 3 using the English /ε/-/æ/ phonemic contrast as the training material. Three experiments were conducted to compare the SED training paradigms that had the background babble implemented either at a constant level (Constant SED) or using the adaptive staircase procedure (Adaptive Staircase SED), and the longevity of the training effects. Results revealed that the Adaptive Staircase SED was the more effective paradigm as it generated greater training benefits and its effect generalized better to the untrained /t/-/d/ phonemic contrast. Training effects from both SED paradigms retained six months after the last training section. Before examining whether SED training leads to improvements in speech production, Chapter 4 investigated the phonetics perception pattern of L1 Mandarin Malaysian speakers, L1 Malaysian English speakers and native British English speakers. The production intelligibility of the L1 Mandarin speakers was also evaluated by the L1 Malaysian English speakers and native British English speakers. Single category assimilation was observed in both L1 Mandarin and L1 Malaysian English speakers whereby the /ε/ and /æ/ phonetic sounds were assimilated to a single/æ/ category (Best, McRoberts, & Goodell, 2001). While the British English speakers showed ceiling performance for all phonetic categories involved, the L1 Malaysian English speakers had difficulty identifying the British English /ε/ phoneme and the L1 Mandarin speakers had difficulty identifying the /d/ final, /ε/ and /æ/ phonemes. As seen by their perceptual performance, the L1 Mandarin speakers also had difficulty producing distinct /d/ final, /ε/ and /æ/ phonemes. Two experiments in Chapter 5 examined whether the effects of SED training generalizes to speech production. The results showed that L1 Malaysian English speakers and native British English speakers found different SED paradigms to be more effective in inducing the production improvement. Only the production intelligibility of the /æ/ phoneme improved as a result of SED training. Collectively, the seven experiments in this thesis showed that SED training was effective in improving Malaysian speakers’ perception and production performance of difficult English phonemic contrasts. Further research should be conducted to examine the efficacy of SED training in improving speech perception and production across different training materials and in speakers who come from different language backgrounds

Sensory Manipulation as a Countermeasure to Robot Teleoperation Delays: System and Evidence

In the field of robotics, robot teleoperation for remote or hazardous environments has become increasingly vital. A major challenge is the lag between command and action, negatively affecting operator awareness, performance, and mental strain. Even with advanced technology, mitigating these delays, especially in long-distance operations, remains challenging. Current solutions largely focus on machine-based adjustments. Yet, there's a gap in using human perceptions to improve the teleoperation experience. This paper presents a unique method of sensory manipulation to help humans adapt to such delays. Drawing from motor learning principles, it suggests that modifying sensory stimuli can lessen the perception of these delays. Instead of introducing new skills, the approach uses existing motor coordination knowledge. The aim is to minimize the need for extensive training or complex automation. A study with 41 participants explored the effects of altered haptic cues in delayed teleoperations. These cues were sourced from advanced physics engines and robot sensors. Results highlighted benefits like reduced task time and improved perceptions of visual delays. Real-time haptic feedback significantly contributed to reduced mental strain and increased confidence. This research emphasizes human adaptation as a key element in robot teleoperation, advocating for improved teleoperation efficiency via swift human adaptation, rather than solely optimizing robots for delay adjustment.Comment: Submitted to Scientific Report

What Meaning Means for Same and Different: A Comparative Study in Analogical Reasoning

The acquisition of relational concepts plays an integral role and is assumed to be a prerequisite for analogical reasoning. Language and token-trained apes (e.g. Premack, 1976; Thompson, Oden, and Boysen, 1997) are the only nonhuman animals to succeed in solving and completing analogies, thus implicating language as the mechanism enabling the phenomenon. In the present study, I examine the role of meaning in the analogical reasoning abilities of three different primate species. Humans, chimpanzees, and rhesus monkeys completed relational match-to-sample (RMTS) tasks with either meaningful or nonmeaningful stimuli. For human participants, meaningfulness facilitated the acquisition of analogical rules. Individual differences were evident amongst the chimpanzees suggesting that meaning can either enable or hinder their ability to complete analogies. Rhesus monkeys did not succeed in either condition, suggesting that their ability to reason analogically, if present at all, may be dependent upon a dimension other than the representational value of stimuli

Implications for automation assistance in unmanned aerial system operator training

2012 Summer.Includes bibliographical references.The integration of automated modules into unmanned systems control has had a positive impact on operational effectiveness across a variety of challenging domains from battlefields and disaster areas to the National Airspace and distant planets. Despite the generally positive nature of such technological progress, however, concerns for complacency and other automation-induced detriments have been established in a growing body of empirical literature derived from both laboratory research and operational reviews. Given the military's demand for new Unmanned Aerial System (UAS) operators, there is a need to explore how such concerns might extend from the operational realm of experienced professionals into the novice training environment. An experiment was conducted to investigate the influence of automation on training efficiency using a Predator UAS simulator developed by the Air Force Research Laboratory (AFRL) in a modified replication of previous research. Participants were trained in a series of basic maneuvers, with half receiving automated support only on a subset of maneuvers. A subsequent novel landing test showed poorer performance for the group that received assistance from automation during training. Implications of these findings are discussed

Spoken English discrimination (SED) training with multilingual Malaysians: effect of adaptive staircase procedure and background babble in high variability phonetic training.

High variability phonetic training (HVPT) has been shown to improve non-native speakers’ perceptual performance in discriminating difficult second language phonemic contrasts (Bradlow, Akahane-Yamada, Pisoni, & Tohkura, 1999; Bradlow, Pisoni, Akahane-Yamada, & Tohkura, 1997; Lively, Logan, & Pisoni, 1993; Lively, Pisoni, Yamada, Tohkura, & Yamada, 1994; Logan, Lively, & Pisoni, 1991). The perceptual learning can be generalized to novel words (Wang & Munro, 2004), novel speakers (Nishi & Kewley-Port, 2007; Richie & Kewley-Port, 2008) and even to speech production (Bradlow et al., 1997). However, the rigidity of the laboratory training settings has limited applications to real life situations. The current thesis examined the effectiveness of a new phonetic training program - the Spoken English Discrimination (SED) training. SED training is a computerized individual training program designed to improve non-native speakers’ bottom-up perceptual sensitivity to discriminate difficult second language (L2) phonemic contrasts. It combines a number of key training features including 1) natural spoken stimuli, 2) highly variable stimuli spoken by multiple speakers, 3) multi-talker babble as background noise and 4) an adaptive staircase procedure that individualizes the level of background babble. The first experiment investigated the potential benefits of different versions of the SED training program. The effect of stimulus variability (single speaker vs. multiple speakers) and design of background babble (constant vs. adaptive staircase) were examined using English voiceless-voiced plosives /t/-/d/ phonemic contrast as the training materials. No improvements were found in the identification accuracy on the /t/-/d/ contrast in post-test, but identification improvements were found on the untrained English /ε/-/æ/ phonemic contrast. The effectiveness of SED training was re-examined in Chapter 3 using the English /ε/-/æ/ phonemic contrast as the training material. Three experiments were conducted to compare the SED training paradigms that had the background babble implemented either at a constant level (Constant SED) or using the adaptive staircase procedure (Adaptive Staircase SED), and the longevity of the training effects. Results revealed that the Adaptive Staircase SED was the more effective paradigm as it generated greater training benefits and its effect generalized better to the untrained /t/-/d/ phonemic contrast. Training effects from both SED paradigms retained six months after the last training section. Before examining whether SED training leads to improvements in speech production, Chapter 4 investigated the phonetics perception pattern of L1 Mandarin Malaysian speakers, L1 Malaysian English speakers and native British English speakers. The production intelligibility of the L1 Mandarin speakers was also evaluated by the L1 Malaysian English speakers and native British English speakers. Single category assimilation was observed in both L1 Mandarin and L1 Malaysian English speakers whereby the /ε/ and /æ/ phonetic sounds were assimilated to a single/æ/ category (Best, McRoberts, & Goodell, 2001). While the British English speakers showed ceiling performance for all phonetic categories involved, the L1 Malaysian English speakers had difficulty identifying the British English /ε/ phoneme and the L1 Mandarin speakers had difficulty identifying the /d/ final, /ε/ and /æ/ phonemes. As seen by their perceptual performance, the L1 Mandarin speakers also had difficulty producing distinct /d/ final, /ε/ and /æ/ phonemes. Two experiments in Chapter 5 examined whether the effects of SED training generalizes to speech production. The results showed that L1 Malaysian English speakers and native British English speakers found different SED paradigms to be more effective in inducing the production improvement. Only the production intelligibility of the /æ/ phoneme improved as a result of SED training. Collectively, the seven experiments in this thesis showed that SED training was effective in improving Malaysian speakers’ perception and production performance of difficult English phonemic contrasts. Further research should be conducted to examine the efficacy of SED training in improving speech perception and production across different training materials and in speakers who come from different language backgrounds

Virtual reality obstacle crossing: adaptation, retention and transfer to the physical world

Virtual reality (VR) paradigms are increasingly being used in movement and exercise sciences with the aim to enhance motor function and stimulate motor adaptation in healthy and pathological conditions. Locomotor training based in VR may be promising for motor skill learning, with transfer of VR skills to the physical world in turn required to benefit functional activities of daily life. This PhD project aims to examine locomotor adaptations to repeated VR obstacle crossing in healthy young adults as well as transfers to the untrained limb and the physical world, and retention potential of the learned skills. For these reasons, the current thesis comprises three studies using controlled VR obstacle crossing interventions during treadmill walking. In the first and second studies we investigated adaptation to crossing unexpectedly appearing virtual obstacles, with and without feedback about crossing performance, and its transfer to the untrained leg. In the third study we investigated transfer of virtual obstacle crossing to physical obstacles of similar size to the virtual ones, that appeared at the same time point within the gait cycle. We also investigated whether the learned skills can be retained in each of the environments over one week. In all studies participants were asked to walk on a treadmill while wearing a VR headset that represented their body as an avatar via real-time synchronised optical motion capture. Participants had to cross virtual and/or physical obstacles with and without feedback about their crossing performance. If applicable, feedback was provided based on motion capture immediately after virtual obstacle crossing. Toe clearance, margin of stability, and lower extremity joint angles in the sagittal plane were calculated for the crossing legs to analyse adaptation, transfer, and retention of obstacle crossing performance. The main outcomes of the first and second studies were that crossing multiple virtual obstacles increased participants’ dynamic stability and led to a nonlinear adaptation of toe clearance that was enhanced by visual feedback about crossing performance. However, independent of the use of feedback, no transfer to the untrained leg was detected. Moreover, despite significant and rapid adaptive changes in locomotor kinematics with repeated VR obstacle crossing, results of the third study revealed limited transfer of learned skills from virtual to physical obstacles. Lastly, despite full retention over one week in the virtual environment we found only partial retention when crossing a physical obstacle while walking on the treadmill. In summary, the findings of this PhD project confirmed that repeated VR obstacle perturbations can effectively stimulate locomotor skill adaptations. However, these are not transferable to the untrained limb irrespective of enhanced awareness and feedback. Moreover, the current data provide evidence that, despite significant adaptive changes in locomotion kinematics with repeated practice of obstacle crossing under VR conditions, transfer to and retention in the physical environment is limited. It may be that perception-action coupling in the virtual environment, and thus sensorimotor coordination, differs from the physical world, potentially inhibiting retained transfer between those two conditions. Accordingly, VR-based locomotor skill training paradigms need to be considered carefully if they are to replace training in the physical world

A novel plasticity rule can explain the development of sensorimotor intelligence

Grounding autonomous behavior in the nervous system is a fundamental challenge for neuroscience. In particular, the self-organized behavioral development provides more questions than answers. Are there special functional units for curiosity, motivation, and creativity? This paper argues that these features can be grounded in synaptic plasticity itself, without requiring any higher level constructs. We propose differential extrinsic plasticity (DEP) as a new synaptic rule for self-learning systems and apply it to a number of complex robotic systems as a test case. Without specifying any purpose or goal, seemingly purposeful and adaptive behavior is developed, displaying a certain level of sensorimotor intelligence. These surprising results require no system specific modifications of the DEP rule but arise rather from the underlying mechanism of spontaneous symmetry breaking due to the tight brain-body-environment coupling. The new synaptic rule is biologically plausible and it would be an interesting target for a neurobiolocal investigation. We also argue that this neuronal mechanism may have been a catalyst in natural evolution.Comment: 18 pages, 5 figures, 7 video

Aerospace medicine and biology: A continuing bibliography with indexes (supplement 386)

This bibliography lists 117 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during Mar. 1994. Subject coverage includes: aerospace medicine and physiology, life support systems and man/system technology, protective clothing, exobiology and extraterrestrial life, planetary biology, and flight crew behavior and performance