Understanding Visual Information Processing for American vs. Saudi Arabian Users

The extent to which impaired visual and phonological mechanisms may contribute to the manifestation of developmental dyslexia across orthographies of varying depth has yet to be fully established. By adopting a cross-linguistic approach, the current study aimed to explore the nature of visual and phonological processing in developmental dyslexic readers of shallow (Italian) and deep (English) orthographies, and specifically the characterisation of visual processing deficits in relation to orthographic depth. To achieve this aim, we administered a battery of non-reading visual and phonological tasks. Developmental dyslexics performed worse than typically developing readers on all visual and phonological tasks. Critically, readers of the shallow orthography were disproportionately impaired on visual processing tasks. Our results suggest that the impaired reading and associated deficits observed in developmental dyslexia are anchored by dual impairments to visual and phonological mechanisms that underpin reading, with the magnitude of the visual deficit varying according to orthographic depth.

This study explored whether benzodiazepines selectively affect aspects of attention and/or visual information processing, as they do memory. A cued visual-search paradigm was employed, using normal volunteers and a single dose of triazolam. This paradigm provided for a detailed examination of two aspects of visual attention and information processing: 1) controlled versus automatic attention allocation (via central and peripheral cues), and 2) the extent to which processing an item in a non-cued location affects performance (via cue-validity). Triazolam, compared to placebo, significantly increased response time, and Drug Condition interacted with Cue-Validity but not Cue-Type. Based on these data, we argue that triazolam does not affect attention allocation but does affect attentional disengagement and/or attention switching mechanisms.

Confluent evidence suggests that aging is associated with a reduction in the spectral slope of neural recordings. This phenomenon has been hypothesized to reflect an increase in the ratio of excitatory and inhibitory (E/I) balance. As neural E/I ratio is considered essential for cognitive functioning, this study investigated whether spectral slope (β) predicts cognitive performance in the older adults and could serve as a potential neural signature of cognitive aging. Nevertheless, few studies have examined how spectral slope estimates obtained from both eyes-closed (EC) and eyes-open (EO) resting states relate to cognitive performance in the aging population. To address this gap, this study analyzed electroencephalography (EEG) recordings of 19 community-dwelling elderly adults (CDE, aged between 60 to 80 years) and 24 young control individuals (YC, aged between 21 to 32 years) collected during EC and EO states. Further, β was estimated from global power spectra after separating scale-free from oscillatory components in the power spectrum. Reduced β was observed in CDE in contrast to YC in both physiological states. While the YC group indicated an increase in β when transitioning from EC to EO, this change could not be observed in CDE. Finally, a strong, anticorrelated relationship between β in EO and performance on a rapid visual information processing task, was typically seen only in the CDE group. These results potentially indicate an altered E/I ratio in the CDE cohort, while the inverse relationship with task performance suggests that this pattern could reflect a compensatory brain mechanism supporting cognition during aging.

Peak Alpha Frequency in Schizophrenia, Bipolar Disorder, and Healthy Volunteers: Associations With Visual Information Processing and Cognition

Event Abstract Back to Event Spatial vision in insects: How visual information processing is facilitated by an active flight and gaze strategy Martin Egelhaaf1*, Roland Kern1 and Jens P. Lindemann1 1 Bielefeld University, Neurobiology & CITEC, Germany Flying insects, such as blowflies and bees rely on the image flow on their eyes (“optic flow”) solving spatial tasks as diverse as collision avoidance and local navigation, i.e. localizing a previously learnt inconspicuous goal on the basis of landmark cues. In free flight flies and bees exhibit characteristic behavioural actions to shape the dynamics of the optic flow. By employing a saccadic flight and gaze strategy they squeeze rotations into brief and rapid turns leaving most of the flight time for various types of translational prototypical movements. Separation of rotational and translational optic flow components by a behavioural strategy is reasonable , since only the optic flow component induced by translations contains information about the relative distance of environmental structures from the animal. By combined electrophysiological analysis and model simulations we analyzed how during rotational and translational self-motion information about the spatial layout and the textural properties of both experimenter-designed and natural environments are represented at the different processing stages of the visual motion pathway. Only two major conclusions shall be mentioned here: (1) during intersaccadic translational flight, the mechanisms of local motion detection segregate in a computationally cheap way natural sceneries into their depth structure: nearby objects pop out in the activity profile of retinotopic arrays of local motion detectors, whereas more distant structures evoke only negligible responses. (2) Even after spatial pooling of local motion signals by the dendritic trees of the wide-field cells in the lobula complex of flies and bees, these distance dependent response modulations persist. Hence, these neurons, which are traditionally conceived as rotation sensors being involved in mediating compensatory optomotor responses, provide information about the spatial properties of the environment. In conclusion, the neural processing of spatial information in flies and bees is greatly facilitated by their saccadic flight and gaze strategy. This active vision strategy enables the nervous system to solve apparently complex spatial vision tasks in a computationally parsimonious way. Thus, by making use of the closed action–perception loop in a smart way, insects with their tiny brains are capable of performing extraordinarily well even on extremely fast timescales of some ten milliseconds. Acknowledgements The work in our lab is supported by the Deutsche Forschungsgemeinschaft (DFG) Keywords: motion vision, Spatial Vision, Optic Flow, collision avoidance, navigation, fly, Honeybee, Bumblebee, Flight control Conference: International Conference on Invertebrate Vision, Fjälkinge, Sweden, 1 Aug - 8 Aug, 2013. Presentation Type: Oral presentation preferred Topic: Motion vision Citation: Egelhaaf M, Kern R and Lindemann JP (2019). Spatial vision in insects: How visual information processing is facilitated by an active flight and gaze strategy. Front. Physiol. Conference Abstract: International Conference on Invertebrate Vision. doi: 10.3389/conf.fphys.2013.25.00044 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 25 Feb 2013; Published Online: 09 Dec 2019. * Correspondence: Prof. Martin Egelhaaf, Bielefeld University, Neurobiology & CITEC, Bielefeld, D-33501, Germany, martin.egelhaaf@uni-bielefeld.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Martin Egelhaaf Roland Kern Jens P Lindemann Google Martin Egelhaaf Roland Kern Jens P Lindemann Google Scholar Martin Egelhaaf Roland Kern Jens P Lindemann PubMed Martin Egelhaaf Roland Kern Jens P Lindemann Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Visual signal detection and lambda responses

In a number of studies, children diagnosed with developmental dyslexia reached normal scores in standard visual processing tasks, and some researchers concluded that visual processing deficits are not involved in the syndrome. The tasks used, however, may be insensitive to anomalous visual information processing strategies used to compensate for an underlying deficit. To determine whether children with dyslexia use anomalous visual processing strategies, a same-different task was applied, in which 2 items identical under rotation and reflection were judged as same. Pairs of letters or dot patterns were used, which were either symmetric or asymmetric in shape. Children with dyslexia performed faster than normal-reading children--in particular, remarkably, with letters. Symmetry of dot patterns facilitated performance in both children with dyslexia and normal-reading children; symmetry of letters facilitated performance in children with dyslexia but not in normal-reading children. Children with dyslexia, therefore, fail to adequately differentiate visual processing of linguistic and non-linguistic materials; they process symmetry in letters similarly to that in shapes, which leads in this particular task to the paradoxical observation of children with dyslexia outperforming normal readers with letters.

The ability to process simultaneously presented auditory and visual information is a necessary component underlying many cognitive tasks. While this ability is often taken for granted, there is evidence that under many conditions auditory input attenuates processing of corresponding visual input. The current study investigated infants' processing of visual input under unimodal and cross-modal conditions. Results of the three reported experiments indicate that different auditory input had different effects on infants' processing of visual information. In particular, unfamiliar auditory input slowed down visual processing, whereas more familiar auditory input did not. These results elucidate mechanisms underlying auditory overshadowing in the course of cross-modal processing and have implications on a variety of cognitive tasks that depend on cross-modal processing.

Chapter 4 - The Contribution of Human Superior Intraparietal Sulcus to Visual Short-Term Memory and Perception

Understanding how the human visual system recognizes objects is one of the key challenges in neuroscience. Inspired by a large body of physiological evidence, a general class of recognition models has emerged, which is based on a hierarchical organization of visual processing, with succeeding stages being sensitive to image features of increasing complexity. However, these models appear to be incompatible with some well-known psychophysical results. Prominent among these are experiments investigating recognition impairments caused by vertical inversion of images, especially those of faces. It has been reported that faces that differ 'featurally' are much easier to distinguish when inverted than those that differ 'configurally'; a finding that is difficult to reconcile with the physiological models. Here, we show that after controlling for subjects' expectations, there is no difference between 'featurally' and 'configurally' transformed faces in terms of inversion effect. This result reinforces the plausibility of simple hierarchical models of object representation and recognition in the cortex.

The present study on the separate and the combined effects of cigarette smoking and alcohol consumption on behavioral, electrocortical and cardiovascular functions involved 20 young female smokers, repeatedly tested on their performance in a visual information processing task before and after drug treatment. Each subject participated in four sessions where they received in a balanced sequence 0.7 g/kg alcohol or placebo followed by either real or sham smoking of a cigarette. The mental task required the subjects to detect sequences of three odd or even digits in a pseudorandom series of single digits presented on a TV screen. By using a variable subject-paced interstimulus interval, mental performance was analyzed continuously in terms of the achieved processing rate. The multivariate assessment of psychophysiological functions included the electrocardiogram, the finger plethysmogram and the electroencephalogram (EEG) measured on four electrode locations (Fz, Cz, P3, P4). The EEG was analyzed both for tonical changes in frequency distribution and for phasic responses to the correctly detected triads (Event-Related Potentials, ERP), yielding a CNV after the second digit and a late positive wave (LP) after the third digit. Cigarette smoking increased the processing rate, while it was decreased by alcohol. Smoking after alcohol diminished the performance decline due to alcohol. Heart rate acceleration and peripheral vasoconstriction were observed after smoking. Alcohol caused dilatation of the finger vessels which was prevented by smoking a cigarette after the drink.(ABSTRACT TRUNCATED AT 250 WORDS)

J. A. Gray's reinforcement sensitivity theory: tests of the joint subsystems hypothesis of anxiety and impulsivity

Visual load and variability of muscle activation: Effects on reactive driving of older adults

Here, we ask which neural regions have neural response patterns that correlate with behavioral performance in a visual processing task. We found that the representational structure across all of high-level visual cortex has the requisite structure to predict behavior. Furthermore, when directly comparing different neural regions, we found that they all had highly similar category-level representational structures. These results point to a ubiquitous and uniform representational structure in high-level visual cortex underlying visual object processing.

Acute effects of lorazepam on visual information processing, perceptual priming and explicit memory are well established. However, visual processing and perceptual priming have rarely been explored in long-term lorazepam users. By exploring these functions it was possible to test the hypothesis that difficulty in processing visual information may lead to deficiencies in perceptual priming. Using a simple blind procedure, we tested explicit memory, perceptual priming and visual perception in 15 long-term lorazepam users and 15 control subjects individually matched according to sex, age and education level. Explicit memory, perceptual priming, and the identification of fragmented pictures were found to be preserved in long-term lorazepam users, contrary to what is usually observed after an acute drug intake. The processing of visual contour, on the other hand, was still significantly impaired. These results suggest that the effects observed on low-level visual perception are independent of the acute deleterious effects of lorazepam on perceptual priming. A comparison of perceptual priming in subjects with low- vs. high-level identification of new fragmented pictures further suggests that the ability to identify fragmented pictures has no influence on priming. Despite the fact that they were treated with relatively low doses and far from peak plasma concentration, it is noteworthy that in long-term users memory was preserved.