julilili42/papers huggingface dataset:
A parametric texture model based on deep convolutional features closely matches texture appearance for humans
2017-08-31

Much of our visual environment consists of texture—"stuff" like cloth, bark or gravel as distinct from "things" like dresses, trees or paths—and we humans are adept at perceiving textures and their subtle variation. How does our visual system achieve this feat? Here we psychophysically evaluate a new parameteric model of texture appearance (the CNN texture model; Gatys et al., 2015) that is based on the features encoded by a deep convolutional neural network (deep CNN) trained to recognise objects in images (the VGG-19; Simonyan and Zisserman, 2015). By cumulatively matching the correlations of deep features up to a given layer (using up to five convolutional layers) we were able to evaluate models of increasing complexity. We used a three-alternative spatial oddity task to test whether model-generated textures could be discriminated from original natural textures under two viewing conditions: when test patches were briefly presented to the parafovea ("single fixation") and when observers were able to make eye movements to all three patches ("inspection"). For 9 of the 12 source textures we tested, the models using more than three layers produced images that were indiscriminable from the originals even under foveal inspection. The venerable parameteric texture model of Portilla and Simoncelli (Portilla and Simoncelli, 2000) was also able to match the appearance of these textures in the single fixation condition, but not under inspection. Of the three source textures our model could not match, two contain strong periodicities. In a second experiment, we found that matching the power spectrum in addition to the deep features used above (Liu et al., 2016) greatly improved matches for these two textures. These results suggest that the features learned by deep CNNs encode statistical regularities of natural scenes that capture important aspects of material perception in humans.
Biophysically plausible neural model for the interaction between visual and motor representations of action
2017-08-31

INTRODUCTION: Action perception and action execution are intrinsically linked in the human brain. Experiments show that concurrent motor execution influences the visual perception of actions. This interaction is mediated by action-selective neurons in premotor and parietal cortex. We have developed a model based on biophysically realistic spiking neurons that accounts for such interactions. METHODS: Our model is based on neural representations of different motor actions by mutually coupled neural fields. One field model represents the perceived action (vision field), and the other one the associated motor program (motor field). They consist of coupled ensembles of Exponential Integrate-and-Fire neurons (Brette et al., 2005), and stabilize travelling local solutions (activity peaks), which either follow the stimulus pattern in the vision field, or propagate autonomously after a 'go-signal' in the motor field. Both fields are coupled by interaction kernels that stabilize solutions with synchronously propagating pulses in both fields. Representations for different actions inhibit each other. We used the model to reproduce the results of several experiments focusing on action-perception coupling and mirror neurons. RESULTS: Consistent with experimental data, this architecture provides a unifying account for spatial and temporal tuning of action-perception coupling (Christensen et al., 2011), and for the influence of action perception on variability of execution (Kilner et al., 2003). The model reproduces the behavior of the neural population vector trajectories of mirror neurons in premotor cortex (Caggiano et al., 2016). Duplication of the model architecture allows to reproduce the spontaneous synchronization of two observers that see each other executing periodic body movements (Schmidt et al., 1990). CONCLUSION: The proposed model reproduces, using a single parameter set, a variety of quite different experiments that address the interactions between action vision and action execution. Since the model uses physiologically plausible circuits it makes a variety of predictions at the single-cell level. Meeting abstract presented at VSS 2017
Relation between Pupil Response and Feedback during Contrast Sensitivity Measurement through Tinted Lenses
2017-08-31

It has been reported that yellow tinted lenses increase the pupil size and it is questionable, if the resulting pupillary light response (PLR) influences the visual performance. The PLR reflects not only the amount of light entering the eye, but also cognitive factors such as visual attention and awareness. The aim of this study was to investigate the relation between pupil response and the presence of an acoustic feedback on contrast sensitivity (CS) measurements under tinted lenses. A CS-test determined the threshold contrast using a sine wave grating at 0.5, 1.5, 3 and 6 cycle per degree each with 50 trials. This CS-test included an adaptive staircase (Ψ-method), a 16-bit gray-level resolution and acoustic feedback indicating correctness. The stimulus was surrounded by a white annular scatter source (adapted from Oculus C-Quant) in order to induce a PLR recorded with an eye-tracker (EyeLink-1000-Plus). CS and PLR were measured monocularly in five experienced participants wearing orange, green, violet and yellow tinted lens under equi-luminant conditions. The relative PRL was averaged over participants and tested spatial frequencies. Relative PLR amplitude was significantly different (p < 0.001) in an ANOVA for the conditions with and without acoustic feedback. In conditions with feedback, this difference in relative PLR was larger for orange and yellow tinted lenses compared to no filter conditions (p < 0.01). The CS measured with acoustic feedback showed no significant improvement compared to no-feedback conditions (p=0.12), although this could be expected due to attentional fluctuations and PLR change. However, there was a tendency for an impact of feedback on CS at lower spatial frequencies. This study suggests a positive relation between pupil response and acoustic feedback during contrast sensitivity measurements. In conclusion, orange and yellow tinted lenses showed a larger PLR, suggesting a direct attentional effect of acoustic feedback on pupil response. Meeting abstract presented at VSS 2017
We know what we can see - peripheral visibility of search targets shapes eye movement behavior in natural scenes
2017-08-31

Influences of target features on fixation locations and search durations have been widely studied. What happens to properties of the eyes' scanpath when looking for different targets has not been investigated as thoroughly. One important target aspect is how far into the periphery it is detectable, which can be varied by changing its spatial frequency content. Here we show that human participants adapt their eye movement behavior immediately when searching for different targets in natural scenes. In our study, participants searched natural scenes for 6 artificial targets with different spatial frequency content. High spatial frequency targets led to shorter fixation durations and smaller saccade amplitudes than low spatial frequency targets. The effect of the smaller saccade amplitudes appeared from the first of eight experimental sessions, without training, persisted throughout all sessions and disappeared when subjects were not told which of the targets to search for. Fixation durations were shorter for high spatial frequency targets after one training session, also persisted throughout all subsequent sessions and disappeared when subjects were not told which of the targets to search for. The differences in eye movement patterns between low and high spatial frequency targets led to longer search times to find the high frequency targets, but the probability to find the target within 10 seconds was unchanged. As high spatial frequency targets can not be detected far into the periphery, it is adaptive to choose a scanning strategy with shorter fixation durations and shorter saccade amplitudes when searching for high spatial frequency targets. Our results suggest that humans are capable to adequately adapt their eye movement behavior instantaneously according to the spatial frequency content of the target, implicitly adapting to how far from the fovea targets can be detected. Meeting abstract presented at VSS 2017
Adaptation to distortions of natural scenes is retained across saccades
2017-08-31

Vision aid optical elements, such as progressive additional power lenses, spatially distort the image of the natural environment disparately across the different parts of the visual field. Eye movements thereby continuously shift the distortions in the retinal plane. While people adapt to such spectacles, the visual system seems to compensate for distortions regardless of their continuous retinal displacements during eye movements. Neural mechanisms involved in distortion adaptation might transfer their plasticity across saccades. Here we used reference frames of adaptation aftereffects to assess if distortion is processed anew at every fixation or if it is retained across saccades to achieve perceptual stability. In a psychophysical experiment, observers viewed geometrically skewed natural image content for 8 minute to induce adaptation. A saccade was subsequently executed to a new fixation point and skew adaptation was measured at retinotopic and spatiotopic locations as well as at a location which was neither retinotopic nor spatiotopic. Adaptation aftereffects were tested in an adjustment procedure. The adaptation aftereffect, i.e. the point of subjective equality (PSE), was defined by the skew amplitude of the test stimuli which was perceived to be undistorted by the observers. The skew adaptation information was partially transferred to the new fixation. Retinotopic and spatiotopic locations showed significant skew adaptation aftereffect wherein the PSE shifted in the direction of the adapting skew direction. In contrast, no aftereffect was observed at the location which was neither retinotopic nor spatiotopic. Therefore, the visual system preserves retinotopic and spatiotopic distortion information across saccades. The spatiotopic distortion information is conceivably used to counterbalance the saccade induced retinal shifts of the distortions, thereby mediating retinotopic and spatiotopic representations of the distortions. Meeting abstract presented at VSS 2017
Testing an Early Vision Model on Natural Image Stimuli
2017-08-31

Early visual processing has been studied extensively over the last decades. From these studies a relatively standard model emerged of the first steps in visual processing. However, most implementations of the standard model cannot take arbitrary images as input, but only the typical grating stimuli used in many of the early vision experiments. Previously we presented an image based early vision model implementing our knowledge about early visual processing including oriented spatial frequency channels, divisive normalization and optimal decoding (Schütt & Wichmann, VSS, 2016). The model explains the classical psychophysical data reasonably well, matching the performance of the non-image based models for contrast detection, contrast discrimination and oblique masking data. Here we report tests of our model using natural images, exploiting the benefits of image based models of visual processing. First, we assessed the performance of the model against human observer thresholds for detecting noise Gabors masked by patches of natural scenes (Alam et. al., JoV, 2014). Our model predicts the thresholds for this masking experiment well, although it slightly overestimates the sensitivity of observers. Second, we investigated the channel activities for natural scene patches fixated by observers in a free viewing eye movement experiment. Before normalization channel activities follow typically observed biases of natural scenes, including the decline in energy over spatial frequency and the stronger activity along the cardinal axes. After divisive inhibition, the distribution activity is no longer skewed towards low spatial frequencies, while the preference for cardinal axes is preserved. Finally, we observe that the channels are extremely sparsely activated: each natural image patch activates few channels and each channel is activated by few stimuli. Thus our model is able to generalize from simple grating stimuli to natural image stimuli, and it reproduces normative desiderata stemming from the efficient coding hypothesis and natural image statistics. Meeting abstract presented at VSS 2017
Integrating Personality Structure, Personality Process, and Personality Development
2017-09-01

In this target article, we argue that personality processes, personality structure, and personality development have to be understood and investigated in integrated ways in order to provide comprehensive responses to the key questions of personality psychology. The psychological processes and mechanisms that explain concrete behaviour in concrete situations should provide explanation for patterns of variation across situations and individuals, for development over time as well as for structures observed in intra–individual and inter–individual differences. Personality structures, defined as patterns of covariation in behaviour, including thoughts and feelings, are results of those processes in transaction with situational affordances and regularities. It cannot be presupposed that processes are organized in ways that directly correspond to the observed structure. Rather, it is an empirical question whether shared sets of processes are uniquely involved in shaping correlated behaviours, but not uncorrelated behaviours (what we term ‘correspondence’ throughout this paper), or whether more complex interactions of processes give rise to population–level patterns of covariation (termed ‘emergence’). The paper is organized in three parts, with part I providing the main arguments, part II reviewing some of the past approaches at (partial) integration, and part III outlining conclusions of how future personality psychology should progress towards complete integration. Working definitions for the central terms are provided in the appendix. Copyright © 2017 European Association of Personality Psychology
Vps13-Mcp1 interact at vacuole–mitochondria interfaces and bypass ER–mitochondria contact sites
2017-09-01

Membrane contact sites between endoplasmic reticulum (ER) and mitochondria, mediated by the ER–mitochondria encounter structure (ERMES) complex, are critical for mitochondrial homeostasis and cell growth. Defects in ERMES can, however, be bypassed by point mutations in the endosomal protein Vps13 or by overexpression of the mitochondrial protein Mcp1. How this bypass operates remains unclear. Here we show that the mitochondrial outer membrane protein Mcp1 functions in the same pathway as Vps13 by recruiting it to mitochondria and promoting its association to vacuole–mitochondria contacts. Our findings support a model in which Mcp1 and Vps13 work as functional effectors of vacuole–mitochondria contact sites, while tethering is mediated by other factors, including Vps39. Tethered and functionally active vacuole–mitochondria interfaces then compensate for the loss of ERMES-mediated ER–mitochondria contact sites.
Treatable inherited rare movement disorders
2017-09-01

ABSTRACT There are many rare movement disorders, and new ones are described every year. Because they are not well recognized, they often go undiagnosed for long periods of time. However, early diagnosis is becoming increasingly important. Rapid advances in our understanding of the biological mechanisms responsible for many rare disorders have enabled the development of specific treatments for some of them. Well‐known historical examples include Wilson disease and dopa‐responsive dystonia, for which specific and highly effective treatments have life‐altering effects. In recent years, similarly specific and effective treatments have been developed for more than 30 rare inherited movement disorders. These treatments include specific medications, dietary changes, avoidance or management of certain triggers, enzyme replacement therapy, and others. This list of treatable rare movement disorders is likely to grow during the next few years because a number of additional promising treatments are actively being developed or evaluated in clinical trials. © 2017 International Parkinson and Movement Disorder Society
Design and validation of a clinical scale for prehospital stroke recognition, severity grading and prediction of large vessel occlusion: the shortened NIH Stroke Scale for emergency medical services
2017-09-01

Objective To develop an NIH Stroke Scale (NIHSS)-compatible, all-in-one scale for rapid and comprehensive prehospital stroke assessment including stroke recognition, severity grading and progression monitoring as well as prediction of large vessel occlusion (LVO). Methods Emergency medical services (EMS) personnel and stroke physicians (n=326) rated each item of the NIHSS regarding suitability for prehospital use; best rated items were included. Stroke recognition was evaluated retrospectively in 689 consecutive patients with acute stroke or stroke mimics, prediction of LVO in 741 consecutive patients with ischaemic stroke with acute vessel imaging independent of admission NIHSS score. Results Nine of the NIHSS items were rated as ‘suitable for prehospital use.’ After excluding two items in order to increase specificity, the final scale (termed shortened NIHSS for EMS, sNIHSS-EMS) consists of ‘level of consciousness’, ‘facial palsy’, ‘motor arm/leg’, ‘sensory’, ‘language’ and ‘dysarthria’. Sensitivity for stroke recognition of the sNIHSS-EMS is 91% (95% CI 86 to 94), specificity 52% (95% CI 47 to 56). Receiver operating curve analysis revealed an optimal cut-off point for LVO prediction of ≥6 (sensitivity 70% (95% CI 65 to 76), specificity 81% (95% CI 76 to 84), positive predictive value 70 (95% CI 65 to 75), area under the curve 0.81 (95% CI 0.78 to 0.84)). Test characteristics were non-inferior to non-comprehensive scales. Conclusions The sNIHSS-EMS may overcome the sequential use of multiple emergency stroke scales by permitting parallel stroke recognition, severity grading and LVO prediction. Full NIHSS-item compatibility allows for evaluation of stroke progression starting at the prehospital phase.
Dynein light chain 1 induces assembly of large Bim complexes on mitochondria that stabilize Mcl-1 and regulate apoptosis
2017-09-01

The Bcl-2 family protein Bim triggers mitochondrial apoptosis. Bim is expressed in nonapoptotic cells at the mitochondrial outer membrane, where it is activated by largely unknown mechanisms. We found that Bim is regulated by formation of large protein complexes containing dynein light chain 1 (DLC1). Bim rapidly inserted into cardiolipin-containing membranes in vitro and recruited DLC1 to the membrane. Bim binding to DLC1 induced the formation of large Bim complexes on lipid vesicles, on isolated mitochondria, and in intact cells. Native gel electrophoresis and gel filtration showed Bim-containing mitochondrial complexes of several hundred kilodaltons in all cells tested. Bim unable to form complexes was consistently more active than complexed Bim, which correlated with its substantially reduced binding to anti-apoptotic Bcl-2 proteins. At endogenous levels, Bim surprisingly bound only anti-apoptotic Mcl-1 but not Bcl-2 or Bcl-X L , recruiting only Mcl-1 into large complexes. Targeting of DLC1 by RNAi in human cell lines induced disassembly of Bim–Mcl-1 complexes and the proteasomal degradation of Mcl-1 and sensitized the cells to the Bcl-2/Bcl-X L inhibitor ABT-737. Regulation of apoptosis at mitochondria thus extends beyond the interaction of monomers of proapoptotic and anti-apoptotic Bcl-2 family members but involves more complex structures of proteins at the mitochondrial outer membrane, and targeting complexes may be a novel therapeutic strategy.
Relationship between subtypes and symptoms of ADHD, insomnia, and nightmares in connection with quality of life in children
2017-09-01

We verified an elevated occurrence of sleep disorders in children with ADHD and were able to link them to specific subtypes of ADHD. These results were in line with our hypothetical model. Moreover, we found a clinically reduced QoL in mean for the whole sample, indicating the strong impact of ADHD in the lives of affected children, even intensified if children exhibited comorbid insomnia and nightmares. These results should be kept in mind regarding the treatment and therapy of this subgroup of children. Specific treatment strategies should be considered for these children.
Outdoor person following at higher speeds using a skid-steered mobile robot
2017-09-01

A new navigation system for outdoor person following at higher speeds (maximum speed ≈2.5 m/s) is proposed. A combination of global and local path planning, and path following control, allows a robot to follow a jogger in various outdoor scenarios, including highly dynamical environments with pedestrians. Our fast path planning provides smooth and obstacle-free paths, even at higher speeds, in the presence of dynamic obstacles and in narrow passages. Our control algorithm allows precise following of the planned paths on different terrain types, including snow and ice. The mobile robot used in the experiments is the skid-steered robot Robotnik Summit XL.
Lutheran Sensory Culture in Context*
2017-09-01

In 1817, the late medieval wall paintings in the Minster of Ulm were whitewashed to prepare the church for the three-hundredth jubilee of the Reformation. These paintings had survived the Zwinglian Reformation in Ulm in 1531 and more than two hundred years of Lutheranism intact. Nonetheless, the consistory in Stuttgart now issued a recommendation to cover the ‘old paintings which often nourished superstition’.1 This late act of reformatory iconoclasm is astonishing: if Lutheran clergymen in Württemberg at the beginning of the nineteenth century thought that the power of images could distract parishioners’ attention from listening to the sermon and lead them into idolatry, they were following Zwingli or Calvin, but certainly not Luther. Purifying the church interior of images represented a clear but probably unconscious break with the ‘preserving power of Lutheranism’ which had left the medieval decoration of its churches largely untouched.2 This shift in attitude towards images indicates that Lutheran visual culture did not remain fixed after the Reformation. Likewise, Lutheran ways of hearing, smelling, tasting and touching were subject to change over the centuries. Did this mean, however, that they became less ‘Lutheran’ as a consequence?3