458 research outputs found

    Volitional control of anticipatory ocular smooth pursuit after viewing, but not pursuing, a moving target: evidence for a re-afferent velocity store

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    Although human subjects cannot normally initiate smooth eye movements in the absence of a moving target, previous experiments have established that such movements can be evoked if the subject is required to pursue a regularly repeated, transient target motion stimulus. We sought to determine whether active pursuit was necessary to evoke such an anticipatory response or whether it could be induced after merely viewing the target motion. Subjects were presented with a succession of ramp target motion stimuli of identical velocity and alternating direction in the horizontal axis. In initial experiments, the target was exposed for only 120 ms as it passed through centre, with a constant interval between presentations. Ramp velocity was varied from +/- 9 to 45 degrees/s in one set of trials; the interval between ramp presentations was varied from 640 to 1920 ms in another. Subjects were instructed either to pursue the moving target from the first presentation or to hold fixation on another, stationary target during the first one, two or three presentations of the moving display. Without fixation, the first smooth movement was initiated with a mean latency of 95 ms after target onset, but with repeated presentations anticipatory smooth movements started to build up before target onset. In contrast, when the subjects fixated the stationary target for three presentations of the moving target, the first movement they made was already anticipatory and had a peak velocity that was significantly greater than that of the first response without prior fixation. The conditions of experiment 1 were repeated in experiment 3 with a longer duration of target exposure (480 ms), to allow higher eye velocities to build up. Again, after three prior fixations, the anticipatory velocity measured at 100 ms after target onset (when visual feedback would be expected to start) was not significantly different to that evoked after the subjects had made three active pursuit responses to the same target motion, reaching a mean of 20 degrees/s for a 50 degrees/s target movement. In a further experiment, we determined whether subjects could use stored information from prior active pursuit to generate anticipatory pursuit in darkness if there was a high expectancy that the target would reappear with identical velocity. Subjects made one predictive response immediately after target disappearance, but very little response thereafter until the time at which they expected the target to reappear, when they were again able to re-vitalize the anticipatory response before target appearance. The findings of these experiments provide evidence that information related to target velocity can be stored and used to generate future anticipatory responses even in the absence of eye movement. This suggests that information for storage is probably derived from a common pre-motor drive signal that is inhibited during fixation, rather than an efference copy of eye movement itself. Furthermore, a high level of expectancy of target appearance can facilitate the release of this stored information in darkness

    Philosophy for Youth

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    A review of Alain Badiou. 2017. 'The True Life', trans. Susan Spitzer, Cambridge and Malden, MA: Polity Press

    Theoretical and empirical investigation of the [tau]-coupling theory

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    Higher degree research by numbers: beyond the critiques of neo-liberalism

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    © 2017 HERDSA. This article argues that strong theories of neo-liberalism do not provide an adequate frame for understanding the ways that measurement practices come to be embedded in the life-worlds of those working in higher education. We argue that neo-liberal metrics need to be understood from the viewpoint of their social usage, alongside other practices of qualification and quantification. In particular, this article maps the specific variables attending measurement in higher degree research programmes, as the key sites that familiarize students with measurement practices around research and teaching. With regard to the incremental reframing of doctoral study as a utilitarian pursuit, we suggest a need to better identify the singular and immeasurable features of long-term research projects, and argue for a revitalized notion of failure. In this context, this article suggests that many critiques of neo-liberalism do not sufficiently advance alternative ways to think about the purposes and limitations of higher education

    A systematic review of protocol studies on conceptual design cognition: design as search and exploration

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    This paper reports findings from the first systematic review of protocol studies focusing specifically on conceptual design cognition, aiming to answer the following research question: What is our current understanding of the cognitive processes involved in conceptual design tasks carried out by individual designers? We reviewed 47 studies on architectural design, engineering design and product design engineering. This paper reports 24 cognitive processes investigated in a subset of 33 studies aligning with two viewpoints on the nature of designing: (V1) design as search (10 processes, 41.7%); and (V2) design as exploration (14 processes, 58.3%). Studies on search focused on solution search and problem structuring, involving: long-term memory retrieval; working memory; operators and reasoning processes. Studies on exploration investigated: co-evolutionary design; visual reasoning; cognitive actions; and unexpected discovery and situated requirements invention. Overall, considerable conceptual and terminological differences were observed among the studies. Nonetheless, a common focus on memory, semantic, associative, visual perceptual and mental imagery processes was observed to an extent. We suggest three challenges for future research to advance the field: (i) developing general models/theories; (ii) testing protocol study findings using objective methods conducive to larger samples and (iii) developing a shared ontology of cognitive processes in design

    Perceptual bias, more than age, impacts on eye movements during face processing

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    Consistent with the right hemispheric dominance for face processing, a left perceptual bias (LPB) is typically demonstrated by younger adults viewing faces and a left eye movement bias has also been revealed. Hemispheric asymmetry is predicted to reduce with age and older adults have demonstrated a weaker LPB, particularly when viewing time is restricted. What is currently unclear is whether age also weakens the left eye movement bias. Additionally, a right perceptual bias (RPB) for facial judgments has less frequently been demonstrated, but whether this is accompanied by a right eye movement bias has not been investigated. To address these issues older and younger adults’ eye movements and gender judgments of chimeric faces were recorded in two time conditions. Age did not significantly weaken the LPB or eye movement bias; both groups looked initially to the left side of the face and made more fixations when the gender judgment was based on the left side. A positive association was found between LPB and initial saccades in the freeview condition and with all eye movements (initial saccades, number and duration of fixations) when time was restricted. The accompanying eye movement bias revealed by LPB participants contrasted with RPB participants who demonstrated no eye movement bias in either time condition. Consequently, increased age is not clearly associated with weakened perceptual and eye movement biases. Instead an eye movement bias accompanies an LPB (particularly under restricted viewing time conditions) but not an RPB

    The Effects of Increased Body Temperature on Motor Control during Golf Putting

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    This study investigated the effect of increased core temperature on the performance outcome and movement kinematics of elite golfers during a golf putting task. The study aimed to examine individual differences in the extent to which increased temperature influenced the rate of putting success, whether increased temperature speeded up the timing of the putting downswing and whether elite golfers changed their movement kinematics during times of thermal stress. Six participants performed 20 putts to each of four putt distances (1, 2, 3, and 4 m) under normal temperature conditions and when core body temperature was increased. There was no significant difference in the number of successful putts between the two temperature conditions, but there was an increase in putterhead velocity at ball impact on successful putts to distances of 1 and 4 m when temperature was elevated. This reflected an increase in swing amplitude rather than a reduction in swing duration as hypothesized. There were individual differences in the motor control response to thermal stress as three of the golfers changed the kinematic parameters used to scale their putting movements to achieve putts of different distances at elevated temperatures. Theoretical implications for these findings and the practical implications for elite golfers and future research are discussed

    Extrinsic tau-coupling and the regulation of interceptive reaching under varying task constraints

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    We investigated a general theory accounting for the guidance of ongoing movements in an interceptive reaching task. The aim was to assess the premise of tau-coupling that the coupling constant k, the ratio of taus(Ï„s) of motion gaps between hand and object, reflects the kinematics of the on-going movement. The spatial and temporal constraints of the interceptive action were manipulated in three task conditions. While the time dependent counterpart of k, K(t) exhibited task effects, k itself could not distinguish between task manipulations. K(t) showed large variability during the initial acceleration phase, small variability during the rest of the movement, and task dependent changes during the final deceleration phase of interception. The findings highlight the importance of clarifying what constitutes as Ï„-coupling

    The effect of false positive feedback on learning an inhibitory-action task in older adults

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    Background/Study Context: Older adults show a greater response to feedback whilst learning than younger adults. To date this has only been shown for receiving veridical feedback, but there is evidence that suggests that receiving false positive feedback may further enhance learning. We tested the hypothesis that receiving false positive feedback, being told you are preforming better than expected, would be more advantageous for older than younger adults when learning an inhibitory-action task. Methods: 42 younger and 34 older adults trained to improve their inhibition and response times on the Simon task. They completed 18 training blocks and a retention test two weeks after training. Participants received either false positive feedback or veridical feedback on their performance at the end of each training session and the start of the next session. Those in the false positive feedback group were told they were performing faster than expected. Results: Both older and younger adults improved their inhibition and response times but receiving false positive feedback did not significantly change their rate of learning on these outcomes. However, false positive feedback did impact on accuracy levels with those receiving this type of feedback making fewer errors. Older adults were slower but more accurate than younger adults, but contrary to our hypothesis they did not benefit more from false positive feedback than younger adults. Conclusion: This first direct comparison of the effects of false positive feedback on older and younger adults showed that the positive impact of false positive feedback does not decline with age. We also demonstrated that feedback given about one aspect of a skill (in this case speed) may in fact influence another aspect of the skill (in this case accuracy). This suggests that false positive feedback could be used as a motivational tool to enhance cognitive-motor learning in older adults, but care needs to be taken when using this, as the feedback may not affect the element of the skill at which it is targeted

    Education, Empowerment and Access to All - Public Legal Education and Massive Open Online Courses at the Law Society of Ireland

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    Since 2014, the Diploma Centre at the Law Society of Ireland (‘the Society’) has implemented a programme of MOOCs; ‘Massive Open Online Courses’ in key areas of practice. This article outlines the provision of Public Legal Education at the Society and how MOOCs align with the mission to widen access to legal education and the legal profession. Of interest to others who may be developing MOOCs, we discuss the instructional design process and feedback from MOOC participants. MOOCs are very much on trend and have received a mixed reception but, subject to course design, they can provide substantial educational benefit and operate as an effective means to widen access to education
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