scholarly journals Effects of visual attention modulation on dynamic effective connectivity and visual fixation during own-face viewing in body dysmorphic disorder

Author(s):  
Wan-wa Wong ◽  
D. Rangaprakash ◽  
Joel P. Diaz-Fong ◽  
Natalie M. Rotstein ◽  
Gerhard S. Hellemann ◽  
...  

AbstractBackgroundIn individuals with body dysmorphic disorder (BDD), selective attention biases and aberrant visual scanning patterns may cause imbalances in global vs. detailed visual processing, contributing to perceptual distortions for appearance. The mechanistic effects of modifying visual attention on brain function in BDD, which may be critical to developing perceptual-based treatments, have not been explored. This study tested the effects of visual-attention modulation on dorsal and ventral visual stream activation and connectivity, and eye behaviors.MethodsWe acquired functional magnetic resonance imaging data in 37 unmedicated adults with BDD and 30 controls. Participants viewed their faces under two conditions: a) unconstrained (naturalistically), and b) holding their gaze on the center of the image (visual-attention modulation), monitored with an eye-tracking camera. We analyzed activation and dynamic effective connectivity in dorsal and ventral visual streams and visual fixation duration.ResultsVisual-attention modulation resulted in longer fixation duration and reduced activation in dorsal and ventral visual streams in both groups compared with naturalistic viewing. Longer fixation duration was associated with greater effective connectivity from V1 to early dorsal visual stream during the second naturalistic viewing, across groups. During naturalistic viewing, there was greater V1 to early dorsal visual stream connectivity after, compared with before, visual-attention modulation.ConclusionsWhen viewing one’s face, longer visual fixation may confer greater communication in dorsal visual system, facilitating global/holistic visual processing. The finding that reduction in visual scanning while viewing one’s face results in persistent effects during unconstrained viewing has implications for perceptual retraining treatment design for BDD.

Author(s):  
Sigrid Hegna Ingvaldsen ◽  
Tora Sund Morken ◽  
Dordi Austeng ◽  
Olaf Dammann

AbstractResearch on retinopathy of prematurity (ROP) focuses mainly on the abnormal vascularization patterns that are directly visible for ophthalmologists. However, recent findings indicate that children born prematurely also exhibit changes in the retinal cellular architecture and along the dorsal visual stream, such as structural changes between and within cortical areas. Moreover, perinatal sustained systemic inflammation (SSI) is associated with an increased risk for ROP and the visual deficits that follow. In this paper, we propose that ROP might just be the tip of an iceberg we call visuopathy of prematurity (VOP). The VOP paradigm comprises abnormal vascularization of the retina, alterations in retinal cellular architecture, choroidal degeneration, and abnormalities in the visual pathway, including cortical areas. Furthermore, VOP itself might influence the developmental trajectories of cerebral structures and functions deemed responsible for visual processing, thereby explaining visual deficits among children born preterm.


2015 ◽  
Vol 45 (10) ◽  
pp. 2111-2122 ◽  
Author(s):  
W. Li ◽  
T. M. Lai ◽  
C. Bohon ◽  
S. K. Loo ◽  
D. McCurdy ◽  
...  

BackgroundAnorexia nervosa (AN) and body dysmorphic disorder (BDD) are characterized by distorted body image and are frequently co-morbid with each other, although their relationship remains little studied. While there is evidence of abnormalities in visual and visuospatial processing in both disorders, no study has directly compared the two. We used two complementary modalities – event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI) – to test for abnormal activity associated with early visual signaling.MethodWe acquired fMRI and ERP data in separate sessions from 15 unmedicated individuals in each of three groups (weight-restored AN, BDD, and healthy controls) while they viewed images of faces and houses of different spatial frequencies. We used joint independent component analyses to compare activity in visual systems.ResultsAN and BDD groups demonstrated similar hypoactivity in early secondary visual processing regions and the dorsal visual stream when viewing low spatial frequency faces, linked to the N170 component, as well as in early secondary visual processing regions when viewing low spatial frequency houses, linked to the P100 component. Additionally, the BDD group exhibited hyperactivity in fusiform cortex when viewing high spatial frequency houses, linked to the N170 component. Greater activity in this component was associated with lower attractiveness ratings of faces.ConclusionsResults provide preliminary evidence of similar abnormal spatiotemporal activation in AN and BDD for configural/holistic information for appearance- and non-appearance-related stimuli. This suggests a common phenotype of abnormal early visual system functioning, which may contribute to perceptual distortions.


2015 ◽  
Vol 45 (16) ◽  
pp. 3491-3503 ◽  
Author(s):  
T. D. Moody ◽  
M. A. Sasaki ◽  
C. Bohon ◽  
M. A. Strober ◽  
S. Y. Bookheimer ◽  
...  

Background.Body dysmorphic disorder (BDD) and anorexia nervosa (AN) are both characterized by distorted perception of appearance. Previous studies in BDD suggest abnormalities in visual processing of own and others’ faces, but no study has examined visual processing of faces in AN, nor directly compared the two disorders in this respect.Method.We collected functional magnetic resonance imaging data on 60 individuals of equivalent age and gender in each of three groups – 20 BDD, 20 weight-restored AN, and 20 healthy controls (HC) – while they viewed images of others’ faces that contained only high or low spatial frequency information (HSF or LSF). We tested hypotheses about functional connectivity within specialized sub-networks for HSF and LSF visual processing, using psychophysiological interaction analyses.Results.The BDD group demonstrated increased functional connectivity compared to HC between left anterior occipital face area and right fusiform face area (FFA) for LSF faces, which was associated with symptom severity. Both BDD and AN groups had increased connectivity compared to HC between FFA and precuneous/posterior cingulate gyrus for LSF faces, and decreased connectivity between FFA and insula. In addition, we found that LSF connectivity between FFA and posterior cingulate gyrus was significantly associated with thoughts about own appearance in AN.Conclusions.Results suggest similar abnormal functional connectivity within higher-order systems for face processing in BDD and AN, but distinct abnormal connectivity patterns within occipito-temporal visual networks. Findings may have implications for understanding relationships between these disorders, and the pathophysiology underlying perceptual distortions.


2012 ◽  
Vol 107 (9) ◽  
pp. 2335-2341 ◽  
Author(s):  
Kiley J. Seymour ◽  
Colin W. G. Clifford

Motion and binocular disparity are two features in our environment that share a common correspondence problem. Decades of psychophysical research dedicated to understanding stereopsis suggest that these features interact early in human visual processing to disambiguate depth. Single-unit recordings in the monkey also provide evidence for the joint encoding of motion and disparity across much of the dorsal visual stream. Here, we used functional MRI and multivariate pattern analysis to examine where in the human brain conjunctions of motion and disparity are encoded. Subjects sequentially viewed two stimuli that could be distinguished only by their conjunctions of motion and disparity. Specifically, each stimulus contained the same feature information (leftward and rightward motion and crossed and uncrossed disparity) but differed exclusively in the way these features were paired. Our results revealed that a linear classifier could accurately decode which stimulus a subject was viewing based on voxel activation patterns throughout the dorsal visual areas and as early as V2. This decoding success was conditional on some voxels being individually sensitive to the unique conjunctions comprising each stimulus, thus a classifier could not rely on independent information about motion and binocular disparity to distinguish these conjunctions. This study expands on evidence that disparity and motion interact at many levels of human visual processing, particularly within the dorsal stream. It also lends support to the idea that stereopsis is subserved by early mechanisms also tuned to direction of motion.


2016 ◽  
Vol 28 (1) ◽  
pp. 111-124 ◽  
Author(s):  
Sabrina Walter ◽  
Christian Keitel ◽  
Matthias M. Müller

Visual attention can be focused concurrently on two stimuli at noncontiguous locations while intermediate stimuli remain ignored. Nevertheless, behavioral performance in multifocal attention tasks falters when attended stimuli fall within one visual hemifield as opposed to when they are distributed across left and right hemifields. This “different-hemifield advantage” has been ascribed to largely independent processing capacities of each cerebral hemisphere in early visual cortices. Here, we investigated how this advantage influences the sustained division of spatial attention. We presented six isoeccentric light-emitting diodes (LEDs) in the lower visual field, each flickering at a different frequency. Participants attended to two LEDs that were spatially separated by an intermediate LED and responded to synchronous events at to-be-attended LEDs. Task-relevant pairs of LEDs were either located in the same hemifield (“within-hemifield” conditions) or separated by the vertical meridian (“across-hemifield” conditions). Flicker-driven brain oscillations, steady-state visual evoked potentials (SSVEPs), indexed the allocation of attention to individual LEDs. Both behavioral performance and SSVEPs indicated enhanced processing of attended LED pairs during “across-hemifield” relative to “within-hemifield” conditions. Moreover, SSVEPs demonstrated effective filtering of intermediate stimuli in “across-hemifield” condition only. Thus, despite identical physical distances between LEDs of attended pairs, the spatial profiles of gain effects differed profoundly between “across-hemifield” and “within-hemifield” conditions. These findings corroborate that early cortical visual processing stages rely on hemisphere-specific processing capacities and highlight their limiting role in the concurrent allocation of visual attention to multiple locations.


2018 ◽  
Vol 49 (15) ◽  
pp. 2617-2625 ◽  
Author(s):  
Ann-Marie Low ◽  
Signe Vangkilde ◽  
Julijana le Sommer ◽  
Birgitte Fagerlund ◽  
Birte Glenthøj ◽  
...  

AbstractBackgroundAttention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder which frequently persists into adulthood. The primary goal of the current study was to (a) investigate attentional functions of stimulant medication-naïve adults with ADHD, and (b) investigate the effects of 6 weeks of methylphenidate treatment on these functions.MethodsThe study was a prospective, non-randomized, non-blinded, 6-week follow-up design with 42 stimulant medication-naïve adult patients with ADHD, and 42 age and parental education-matched healthy controls. Assessments included measures of visual attention, based on Bundesen's Theory of Visual Attention (TVA), which yields five precise measures of aspects of visual attention; general psychopathology; ADHD symptoms; dyslexia screening; and estimates of IQ.ResultsAt baseline, significant differences were found between patients and controls on three attentional parameters: visual short-term memory capacity, threshold of conscious perception, and to a lesser extent visual processing speed. Secondary analyses revealed no significant correlations between TVA parameter estimates and severity of ADHD symptomatology. At follow-up, significant improvements were found specifically for visual processing speed; this improvement had a large effect size, and remained when controlling for re-test effects, IQ, and dyslexia screen performance. There were no significant correlations between changes in visual processing speed and changes in ADHD symptomatology.ConclusionsADHD in adults may be associated with deficits in three distinct aspects of visual attention. Improvements after 6 weeks of medication are seen specifically in visual processing speed, which could represent an improvement in alertness. Clinical symptoms and visual attentional deficits may represent separate aspects of ADHD in adults.


2018 ◽  
Vol 76 (2) ◽  
pp. 85-88 ◽  
Author(s):  
Marina Marcondes Braga ◽  
Renato Nickel ◽  
Marcos Lange ◽  
Élcio Juliato Piovesan

ABSTRACT Objective: The aim of the present study was to conduct an exploratory assessment of visual impairment following stroke, and to discuss the possibilities of reintroducing patients to the activity of driving. Methods: The Useful Field of View test was used to assess visual processing and visual attention. Results: A total of 18 patients were included in the study, and were assigned to either the drive group (n = 9) or the intention group (n = 9). In the drive group, one patient was categorized as moderate-to-high risk; whereas, in the intention group, one patient was categorized as low-to-moderate risk. Additionally, two patients in the intention group were categorized as high risk. The patients did not perceive their visual deficits as a limitation. Conclusion: Visual attention is an interference factor in terms of the safe performance of driving after a stroke. All patients showed a high level of interest for the independence provided through being able to drive.


NeuroImage ◽  
2009 ◽  
Vol 47 ◽  
pp. S72
Author(s):  
J.D. Feusner ◽  
T. Moody ◽  
E. Hembacher ◽  
H. Moller ◽  
S.Y. Bookheimer

2011 ◽  
Vol 23 (3) ◽  
pp. 661-669 ◽  
Author(s):  
Daniela Balslev ◽  
Emma Gowen ◽  
R. Chris Miall

The oculomotor and spatial attention systems are interconnected. Whereas a link between motor commands and spatial shifts in visual attention is demonstrated, it is still unknown whether the recently discovered proprioceptive signal in somatosensory cortex impacts on visual attention, too. This study investigated whether visual targets near the perceived direction of gaze are detected more accurately than targets further away, despite the equal eccentricity of their retinal projections. We dissociated real and perceived eye position using left somatosensory repetitive transcranial magnetic stimulation (rTMS), which decreases cortical processing of eye muscle proprioceptive inflow and produces an underestimation of the rotation of the right eye. Participants detected near-threshold visual targets presented in the left or right visual hemifield at equal distance from fixation. We have previously shown that when the right eye is rotated to the left of the parasagittal plane, TMS produces an underestimation of this rotation, shifting perceived eye position to the right. Here we found that, in this condition, TMS also decreased target detection in the left visual hemifield and increased it in the right. This effect depended on the direction of rotation of the right eye. When the right eye was rotated rightward and TMS, we assume, shifted perceived gaze direction in opposite direction, leftward, visual accuracy decreased now in the right hemifield. We suggest that the proprioceptive eye position signal modulates the spatial distribution of visual processing resources, producing “pseudo-neglect” for objects located far relative to near the perceived direction of gaze.


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