1
|
Zheng X, Xu G, Du Y, Li H, Han C, Tian P, Li Z, Du C, Yan W, Zhang S. Does Oblique Effect Affect SSVEP-Based Visual Acuity Assessment? Front Neurosci 2022; 15:784888. [PMID: 35095398 PMCID: PMC8795862 DOI: 10.3389/fnins.2021.784888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 12/08/2021] [Indexed: 11/13/2022] Open
Abstract
This study aimed to explore whether there was an effect on steady-state visual evoked potential (SSVEP) visual acuity assessment from the oblique effect or the stimulus orientation. SSVEPs were induced by seven visual stimuli, e.g., the reversal sinusoidal gratings with horizontal, two oblique, and vertical orientations, reversal checkerboards with vertical and oblique orientations, and oscillating expansion-contraction concentric-rings, at six spatial frequency steps. Ten subjects participated in the experiment. Subsequently, a threshold estimation criterion was used to determine the objective SSVEP visual acuity corresponding to each visual stimulus. Taking the SSVEP amplitude and signal-to-noise-ratio (SNR) of the fundamental reversal frequency as signal characteristics, both the SSVEP amplitude and SNR induced by the reversal sinusoidal gratings at 3.0 cpd among four stimulus orientations had no significant difference, and the same finding was also shown in the checkerboards between vertical and oblique orientation. In addition, the SSVEP visual acuity obtained by the threshold estimation criterion for all seven visual stimuli showed no significant difference. This study demonstrated that the SSVEPs induced by all these seven visual stimuli had a similarly good performance in evaluating visual acuity, and the oblique effect or the stimulus orientation had little effect on SSVEP response as well as the SSVEP visual acuity.
Collapse
Affiliation(s)
- Xiaowei Zheng
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
| | - Guanghua Xu
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
- State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an, China
- *Correspondence: Guanghua Xu,
| | - Yuhui Du
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
| | - Hui Li
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
| | - Chengcheng Han
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
| | - Peiyuan Tian
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
| | - Zejin Li
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
| | - Chenghang Du
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
| | - Wenqiang Yan
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
| | - Sicong Zhang
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China
| |
Collapse
|
2
|
Gu L, Wang Y, Feng L, Li S, Zhang M, Ye Q, Zhuang Y, Lu ZL, Li J, Yuan J. Meridian-Specific and Post-Optical Deficits of Spatial Vision in Human Astigmatism: Evidences From Psycho-Physical and EEG Scalings. Front Psychol 2021; 12:595536. [PMID: 33815196 PMCID: PMC8010696 DOI: 10.3389/fpsyg.2021.595536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 02/23/2021] [Indexed: 11/13/2022] Open
Abstract
Previous studies have demonstrated that orientation-specific deprivation in early life can lead to neural deficits of spatial vision in certain space, and can even result in meridional amblyopia (MA). Individuals with astigmatism are the optimal and natural models for exploring this asymmetric development of spatial vision in the human visual system. This study aims to assess the contrast sensitivity function (CSF) and EEG signals along two principal meridians in participants with regular astigmatism when being optimal optical corrected. Twelve participants with astigmatism (AST group, 20 eyes) and thirteen participants with (MA group, 19 eyes) were recruited in the current study. CSFs and spatial sweep visual evoked potentials (sVEP) were measured with vertical and horizontal sinewave gratings along two principal meridians monocularly. Area under log CSF (AULCSF), spatial frequency threshold corresponding to 80% contrast gratings (SF threshold at 80% ctr), and CSF acuity were calculated from CSF test. In addition, sVEP amplitudes and thresholds were calculated with the recursive least square method. Participants with astigmatism exhibited marked vertical-horizontal resolution disparities even after they were corrected with optimal optical corrections. CSF tests showed that AULCSF along weak meridian (measured with horizontal gratings) was lower than that along strong meridian (measured with vertical gratings) in both groups. Significant meridional disparity of CSF acuity was also found in both groups. In addition, the MA group showed larger meridional disparity compared to the AST group. Spatial sVEP thresholds also supported the existence of marked meridional disparity. Our results suggest that meridian-specific partial deprivation in early life might lead to monocularly asymmetric development of spatial vision in the human visual system. In terms of application, we tested the feasibility and reliability of adopting psychophysical and EEG scalings to investigate the asymmetric development of spatial vision related to astigmatism. These paradigms are potentially applicable to reduce and even eliminate the meridional disparity in the primary visual cortex by adopting perceptual learning or other vision-related interventions.
Collapse
Affiliation(s)
- Li Gu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yiyao Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Lei Feng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Saiqun Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Mengwei Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Qingqing Ye
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yijing Zhuang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Zhong-Lin Lu
- Division of Arts and Sciences, NYU Shanghai, Shanghai, China.,Center for Neural Science, Department of Psychology, New York University, New York, NY, United States.,NYU-ECNU Institute of Cognitive Neuroscience, NYU Shanghai, Shanghai, China
| | - Jinrong Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jin Yuan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
3
|
Assessment of Human Visual Acuity Using Visual Evoked Potential: A Review. SENSORS 2020; 20:s20195542. [PMID: 32998208 PMCID: PMC7582995 DOI: 10.3390/s20195542] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/16/2020] [Accepted: 09/25/2020] [Indexed: 01/23/2023]
Abstract
Visual evoked potential (VEP) has been used as an alternative method to assess visual acuity objectively, especially in non-verbal infants and adults with low intellectual abilities or malingering. By sweeping the spatial frequency of visual stimuli and recording the corresponding VEP, VEP acuity can be defined by analyzing electroencephalography (EEG) signals. This paper presents a review on the VEP-based visual acuity assessment technique, including a brief overview of the technique, the effects of the parameters of visual stimuli, and signal acquisition and analysis of the VEP acuity test, and a summary of the current clinical applications of the technique. Finally, we discuss the current problems in this research domain and potential future work, which may enable this technique to be used more widely and quickly, deepening the VEP and even electrophysiology research on the detection and diagnosis of visual function.
Collapse
|
4
|
Yap TP, Luu CD, Suttle C, Chia A, Boon MY. Effect of Stimulus Orientation on Visual Function in Children with Refractive Amblyopia. Invest Ophthalmol Vis Sci 2020; 61:5. [PMID: 32392311 PMCID: PMC7405838 DOI: 10.1167/iovs.61.5.5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Purpose We investigated and characterized the patterns of meridional anisotropies in newly diagnosed refractive amblyopes using pattern onset–offset visual evoked potentials (POVEPs) and psychophysical grating acuity (GA). Methods Twenty-five refractive amblyopes were recruited and compared with non-amblyopic controls from our previous study. Monocular POVEPs were recorded in response to sinewave 4 cycles per degree (cpd) grating stimuli oriented along each individual participants' principal astigmatic meridians, which were approximately horizontal (meridian 1) and vertical (meridian 2). Binocular POVEPs in response to the same stimuli, but oriented at 45°, 90°, 135°, and 180°, were recorded. Psychophysical GAs were assessed along the same meridians using a two-alternative non-forced-choice technique. The C3 amplitudes and peak latencies of the POVEPs and GAs were compared across meridians for both groups (refractive amblyopes and controls) using linear mixed models (monocular) and ANOVA (binocular), and post hoc analysis was conducted to determine if meridional anisotropies in this cohort of amblyopes were related to low (≤1.50 diopters [D]), moderate (1.75–2.75 D) and high (≥3.00 D) astigmatism. Results In the newly diagnosed refractive amblyopes, there were no significant meridional anisotropies across all outcome measures, but the post hoc analysis demonstrated that C3 amplitude was significantly higher in those with low (P = 0.02) and moderate (P = 0.004) astigmatism compared to those with high astigmatism. Refractive amblyopes had poorer GA and C3 amplitudes compared to controls by approximately two lines on the logMAR chart (monocular: P = 0.013; binocular: P = 0.014) and approximately 6 µV (monocular: P = 0.009; binocular: P = 0.027), respectively. Conclusions Deleterious effects of high astigmatism was evident in newly diagnosed refractive amblyopes, but the neural deficits do not seem to be orientation-specific for the stimulus parameters investigated.
Collapse
|
5
|
Li K, Bi Y, Wang Y, Zhang M, Liu YJ, Yang H, Lin F. The Disentangled Sub-Processes Involved in Implied Motion Contributing to Food Freshness: The Neural Evidence from ERPs. Adv Cogn Psychol 2020; 15:185-198. [PMID: 32426079 PMCID: PMC7218451 DOI: 10.5709/acp-0267-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Implied motion can enhance the consumer’s judgment of food freshness. However, this enhancing effect has only been investigated for a few products. Furthermore, researchers have not conclusively determined whether the effects of the low-level visual sensory processing and high-level conceptual processing on food evaluation differ. In Experiment 1, using different fruits in static water (fruit_IS), fruit with implied moving water (fruit_IM), or only fruits as stimuli, we initially generalized the effect of implied motion on the broader category of fruit, and implied motion improved the perceived freshness of the fruit. In Experiment 2, we recorded event-related potentials (ERPs) and measured the temporal processes involved in the mechanism by which implied motion improved perceived fruit freshness. The behavioral results further supported the findings from Experiment 1. The ERP data revealed a pronounced positive difference between fruit_IM and fruit-only conditions recorded from posterior electrodes at approximately 200-300 ms (P2). This difference reflected the low-level visual implied motion sensory processing involved in the effect of implied motion on improving food freshness. Additionally, an early frontocentral negativity difference of approximately 300-500 ms between fruit_IM and fruit-only conditions was recorded, which reflected the high-level visual conceptual processing involved in the effect of implied motion on improving food freshness. These results strengthen and extend previous behavioral findings indicating that implied motion enhances the consumer’s judgment of food freshness across various food categories, and improves our understanding of the cognitive processes involved in the mechanism by which implied motion influences food judgments.
Collapse
Affiliation(s)
- Kaiyun Li
- School of Education and Psychology, University of Jinan, Jinan 250022, China
| | - Yan Bi
- School of Education and Psychology, University of Jinan, Jinan 250022, China
| | - Yifan Wang
- School of Education and Psychology, University of Jinan, Jinan 250022, China
| | - Mingxian Zhang
- School of Education and Psychology, University of Jinan, Jinan 250022, China
| | - Yong-Jin Liu
- Beijing National Research Center for Inforation Science and Technology, Department of Computer Science and Technology, Tsinghua University, Beijing 100074, China
| | - Huijing Yang
- School of Education and Psychology, University of Jinan, Jinan 250022, China
| | - Fengxun Lin
- School of Education and Psychology, University of Jinan, Jinan 250022, China
| |
Collapse
|
6
|
Peven JC, Chen Y, Guo L, Zhan L, Boots EA, Dion C, Libon DJ, Heilman KM, Lamar M. The oblique effect: The relationship between profiles of visuospatial preference, cognition, and brain connectomics in older adults. Neuropsychologia 2019; 135:107236. [PMID: 31654648 DOI: 10.1016/j.neuropsychologia.2019.107236] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 09/20/2019] [Accepted: 10/18/2019] [Indexed: 01/21/2023]
Abstract
The oblique effect (OE) describes the visuospatial advantage for identifying stimuli oriented horizontally or vertically rather than diagonally; little is known about brain aging and the OE. We investigated this relationship using the Judgment of Line Orientation (JLO) in 107 older adults (∼age = 67.8 ± 6.6; 51% female) together with neuropsychological tests of executive functioning (EF), attention/information processing (AIP), and neuroimaging. Only JLO lines falling between 36-54° or 126-144° were considered oblique. To quantify the oblique effect, we calculated z-scores for oblique errors (zOblique = #oblique errors/#oblique lines), and similarly, horizontal + vertical line errors (zHV), and a composite measure of oblique relative to HV errors (zOE). Composite z-scores of EF and AIP reflected domains associated with JLO performance. Graph theory analysis integrated T1-derived volumetry and diffusion MRI-derived white matter tractography into connectivity matrices analyzed for select network properties. Participants produced more zOblique than zHV errors (p < 0.001). Age was not associated with zOE adjusting for sex, education, and MMSE. Similarly adjusted linear regression models revealed that lower EF was associated with a larger oblique effect (p < 0.001). Modular analyses of neural connectivity revealed a differential patterns of network affiliation that varied by high versus low group status determined via median split of zOblique and zHV errors, separately. Older adults exhibit the oblique effect and it is associated with specific cognitive processes and regional brain networks that may facilitate future investigations of visuospatial preference in aging.
Collapse
Affiliation(s)
- Jamie C Peven
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA, United States; Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, United States.
| | - Yurong Chen
- Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Lei Guo
- Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Liang Zhan
- Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Elizabeth A Boots
- Department of Psychology, University of Illinois at Chicago, Chicago, IL, USA; Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Catherine Dion
- Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA
| | - David J Libon
- Department of Geriatrics and Gerontology, New Jersey Institute for Successful Aging, School of Osteopathic Medicine, Rowan University, USA; Department of Psychology, New Jersey Institute for Successful Aging, School of Osteopathic Medicine, Rowan University, USA
| | - Kenneth M Heilman
- Department of Neurology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Melissa Lamar
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA; Department of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA.
| |
Collapse
|
7
|
Yap TP, Luu CD, Suttle CM, Chia A, Boon MY. Electrophysiological and Psychophysical Studies of Meridional Anisotropies in Children With and Without Astigmatism. Invest Ophthalmol Vis Sci 2019; 60:1906-1913. [PMID: 31042798 DOI: 10.1167/iovs.18-25924] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose We investigated the pattern of meridional anisotropies, if any, for pattern onset-offset visual evoked potential (POVEPs) responses and psychophysical grating acuity (GA) in children with normal letter visual acuity (20/20 or better). Methods A total of 29 children (aged 3-9 years), nine of whom were astigmatic (AS), were recruited. Orientation-specific monocular POVEPs were recorded in response to sinewave grating stimuli oriented along the subjects' principal AS meridians. Horizontal and vertical gratings were designated Meridians 1 and 2, respectively, for nonastigmatic patients (Non-AS). Binocular POVEPs in response to the same stimuli, but oriented at 45°, 90°, 135°, and 180°, were recorded. Psychophysical GAs were assessed monocularly and binocularly along the same meridians using the same stimuli by a 2-alternative-forced-choice staircase technique. The C3 amplitudes and peak latencies of the POVEP and GAs were compared across meridians using linear mixed models (monocular) and ANOVA (binocular). Results There were significant meridional anisotropies in monocular C3 amplitudes regardless of astigmatism status (P = 0.001): Meridian 2 (mean ± SE Non-AS, 30.13 ± 2.07 μV; AS, 26.53 ± 2.98 μV) was significantly higher than Meridian 1 (Non-AS, 26.14 ± 1.87 μV; AS, 21.68 ± 2.73 μV; P = 0.019), but no meridional anisotropies were found for GA or C3 latency. Binocular C3 amplitude in response to horizontally oriented stimuli (180°, 29.71 ± 3.06 μV) was significantly lower than the oblique (45°, 36.62 ± 3 .05 μV; P = 0.03 and 135°, 35.95 ± 2.92 μV; P = 0.04) and vertical (90°, 37.82 ± 3.65 μV; P = 0.02) meridians, and binocular C3 latency was significantly shorter in response to vertical than oblique gratings (P ≤ 0.001). Conclusions Meridional anisotropy was observed in children with normal vision. The findings suggest that horizontal gratings result in a small, but significantly lower POVEP amplitude than for vertical and oblique gratings.
Collapse
Affiliation(s)
- Tiong Peng Yap
- School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia
| | - Chi D Luu
- Centre for Eye Research Australia; Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia.,Department of Surgery (Ophthalmology), The University of Melbourne, Parkville, Victoria, Australia
| | - Catherine M Suttle
- School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia.,Division of Optometry and Visual Sciences, School of Health Sciences, City, University of London, United Kingdom
| | - Audrey Chia
- Pediatric Ophthalmology and Adult Strabismus Department, Singapore National Eye Centre (SNEC), Singapore.,Pediatric Ophthalmology and Strabismus Department, KK Women's and Children's Hospital (KKH), Singapore
| | - Mei Ying Boon
- School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia
| |
Collapse
|
8
|
Li K, Yang H, Qi X, Lin F, Chen G, Zhao M. Real-Time Neural Signals of Disorder and Order Perception. Front Psychol 2019; 10:357. [PMID: 30853927 PMCID: PMC6395426 DOI: 10.3389/fpsyg.2019.00357] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 02/05/2019] [Indexed: 11/13/2022] Open
Abstract
Order and disorder are prevalent in everyday life, yet little is known about the neural real-time processing that occurs during the perception of disorder relative to order. In the present study, from a cognitive perspective, by adopting the ERP method, we aimed to examine the elicited real-time neural signals of disorder and order perception when participants processed physical environmental and basic visual disorder and order pictures in an irrelevant red or green rectangle detection task, and we attempted to test the hypothesis of cognitive disfluency in disorder perception. Generally, we observed that at each measured time interval, the ERPs elicited by order stimuli were more positive (less negative) in amplitude than those elicited by disorder stimuli at the frontal electrodes (represented by F7/F8, FT7/FT8, Fz, and FCz), whereas at the posterior electrodes (represented by P7/P8, PO7/PO8, Pz, and POz), the opposite was true. These data reveal for the first time the neural underpinnings of disorder and order perception, extending our understanding of the nature of disorder and order. This study also contributes to the cognitive fluency literature and indirectly expands the research on disorder and order stimuli in cognitive fluency.
Collapse
Affiliation(s)
- Kaiyun Li
- School of Education and Psychology, University of Jinan, Jinan, China
| | - Huijing Yang
- School of Education and Psychology, University of Jinan, Jinan, China
| | - Xiaoning Qi
- School of Education and Psychology, University of Jinan, Jinan, China
| | - Fengxun Lin
- School of Education and Psychology, University of Jinan, Jinan, China
| | - Gongxiang Chen
- School of Education and Psychology, University of Jinan, Jinan, China
| | - Minfang Zhao
- School of Education Science, Huizhou University, Huizhou, China
| |
Collapse
|
9
|
Jack BN, Roeber U, O’Shea RP. Do early neural correlates of visual consciousness show the oblique effect? A binocular rivalry and event-related potential study. PLoS One 2017; 12:e0188979. [PMID: 29232704 PMCID: PMC5726736 DOI: 10.1371/journal.pone.0188979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 11/16/2017] [Indexed: 11/18/2022] Open
Abstract
When dissimilar images are presented one to each eye, we do not see both images; rather, we see one at a time, alternating unpredictably. This is called binocular rivalry, and it has recently been used to study brain processes that correlate with visual consciousness, because perception changes without any change in the sensory input. Such studies have used various types of images, but the most popular have been gratings: sets of bright and dark lines of orthogonal orientations presented one to each eye. We studied whether using cardinal rival gratings (vertical, 0°, and horizontal, 90°) versus oblique rival gratings (left-oblique, -45°, and right-oblique, 45°) influences early neural correlates of visual consciousness, because of the oblique effect: the tendency for visual performance to be greater for cardinal gratings than for oblique gratings. Participants viewed rival gratings and pressed keys indicating which of the two gratings they perceived, was dominant. Next, we changed one of the gratings to match the grating shown to the other eye, yielding binocular fusion. Participants perceived the rivalry-to-fusion change to the dominant grating and not to the other, suppressed grating. Using event-related potentials (ERPs), we found neural correlates of visual consciousness at the P1 for both sets of gratings, as well as at the P1-N1 for oblique gratings, and we found a neural correlate of the oblique effect at the N1, but only for perceived changes. These results show that the P1 is the earliest neural activity associated with visual consciousness and that visual consciousness might be necessary to elicit the oblique effect.
Collapse
Affiliation(s)
- Bradley N. Jack
- Discipline of Psychology, School of Health and Human Sciences, Southern Cross University, Coffs Harbour, Australia
- School of Psychology, UNSW Sydney, Sydney, Australia
| | - Urte Roeber
- Discipline of Psychology, School of Health and Human Sciences, Southern Cross University, Coffs Harbour, Australia
- Institute for Psychology, University of Leipzig, Leipzig, Germany
- Discipline of Biomedical Science, University of Sydney, Sydney, Australia
- School of Psychology and Exercise Science, Murdoch University, Perth, Australia
| | - Robert P. O’Shea
- Discipline of Psychology, School of Health and Human Sciences, Southern Cross University, Coffs Harbour, Australia
- Institute for Psychology, University of Leipzig, Leipzig, Germany
- School of Psychology and Exercise Science, Murdoch University, Perth, Australia
| |
Collapse
|
10
|
Pantazis D, Fang M, Qin S, Mohsenzadeh Y, Li Q, Cichy RM. Decoding the orientation of contrast edges from MEG evoked and induced responses. Neuroimage 2017; 180:267-279. [PMID: 28712993 DOI: 10.1016/j.neuroimage.2017.07.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 06/09/2017] [Accepted: 07/12/2017] [Indexed: 10/19/2022] Open
Abstract
Visual gamma oscillations have been proposed to subserve perceptual binding, but their strong modulation by diverse stimulus features confounds interpretations of their precise functional role. Overcoming this challenge necessitates a comprehensive account of the relationship between gamma responses and stimulus features. Here we used multivariate pattern analyses on human MEG data to characterize the relationships between gamma responses and one basic stimulus feature, the orientation of contrast edges. Our findings confirmed we could decode orientation information from induced responses in two dominant frequency bands at 24-32 Hz and 50-58 Hz. Decoding was higher for cardinal than oblique orientations, with similar results also obtained for evoked MEG responses. In contrast to multivariate analyses, orientation information was mostly absent in univariate signals: evoked and induced responses in early visual cortex were similar in all orientations, with only exception an inverse oblique effect observed in induced responses, such that cardinal orientations produced weaker oscillatory signals than oblique orientations. Taken together, our results showed multivariate methods are well suited for the analysis of gamma oscillations, with multivariate patterns robustly encoding orientation information and predominantly discriminating cardinal from oblique stimuli.
Collapse
Affiliation(s)
- Dimitrios Pantazis
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Mingtong Fang
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sheng Qin
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yalda Mohsenzadeh
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Quanzheng Li
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | | |
Collapse
|
11
|
Li K, Liu YJ, Qu F, Fu X. Neural activity associated with attention orienting triggered by implied action cues. Brain Res 2016; 1642:353-363. [PMID: 27067186 DOI: 10.1016/j.brainres.2016.04.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 03/31/2016] [Accepted: 04/07/2016] [Indexed: 11/30/2022]
Abstract
Spatial attention can be directed by the actions of others. We used ERPs method to investigate the neural underpins associated with attention orienting which is induced by implied body action. Participants performed a standard non-predictive cuing task, in which a directional implied action (throwing and running) or non-action (standing) cue was randomly presented and then followed by a target to the left or right of the central cue, despite cue direction. The cue-triggered ERPs results demonstrated that implied action cues, rather than the non-action cue, could shift the observers' spatial attention as demonstrated by the robust anterior directing attention negativity (ADAN) effects in throwing and running cues. Further, earlier N1 (100-170ms) and P2 (170-260ms) waveform differences occurred between implied action and non-action cues over posterior electrodes. The P2 component might reflect implied motion signal perception of implied action cues, and this implied motion perception might play an important role in facilitating the attentional shifts induced by implied action cues. Target-triggered ERPs data (mainly P3a component) indicated that implied action cues (throwing and running) speeded and enhanced the responses to valid targets compared to invalid targets. Furthermore, P3a might imply that implied action orienting may share similar mechanisms of action with voluntary attention, especially at the novel stimuli processing decision-level. These results further support previous behavioral findings that implied body actions direct spatial attention and extend our understanding about the nature of the attentional shifts that are elicited by implied action cues.
Collapse
Affiliation(s)
- Kaiyun Li
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yong-Jin Liu
- Tsinghua National Laboratory for Information Science and Technology, Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China
| | - Fangbing Qu
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaolan Fu
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China.
| |
Collapse
|
12
|
Takács E, Sulykos I, Czigler I, Barkaszi I, Balázs L. Oblique effect in visual mismatch negativity. Front Hum Neurosci 2013; 7:591. [PMID: 24068991 PMCID: PMC3779865 DOI: 10.3389/fnhum.2013.00591] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 09/02/2013] [Indexed: 11/26/2022] Open
Abstract
We investigated whether visual orientation anisotropies (known as oblique effect) exist in non-attended visual changes using event-related potentials (ERP). We recorded visual mismatch negativity (vMMN) which signals violation of sequential regularities. In the visual periphery unattended, task-irrelevant Gábor patches were displayed in an oddball sequence while subjects performed a tracking task in the central field. A moderate change (50°) in the orientation of stimuli revealed no consistent change-related components. However, we found orientation-related differences around 170 ms in occipito-temporal areas in the amplitude of the ERPs evoked by standard stimuli. In a supplementary experiment we determined the amount of orientation difference that is needed for change detection in an active, attended paradigm. Results exhibited the classical oblique effect; subjects detected 10° deviations from cardinal directions, while threshold from oblique directions was 17°. These results provide evidence that perception of change could be accomplished at significantly smaller thresholds, than what elicits vMMN. In Experiment 2 we increased the orientation change to 90°. Deviant-minus-standard difference was negative in occipito-parietal areas, between 120 and 200 ms after stimulus onset. VMMNs to changes from cardinal angles were larger and more sustained than vMMNs evoked by changes from oblique angles. Changes from cardinal orientations represent a more detectable signal for the automatic change detection system than changes from oblique angles, thus increased vMMN to these “larger” deviances might be considered a variant of the magnitude of deviance effect rarely observed in vMMN studies.
Collapse
Affiliation(s)
- Endre Takács
- Research Centre for Natural Sciences, Institute of Cognitive Neuroscience and Psychology, Hungarian Academy of Sciences Budapest, Hungary ; Faculty of Education and Psychology, Eötvös Loránd University Budapest, Hungary
| | | | | | | | | |
Collapse
|
13
|
Tsuruhara A, Nagata Y, Suzuki M, Inui K, Kakigi R. Effects of spatial frequency on visual evoked magnetic fields. Exp Brain Res 2013; 226:347-55. [DOI: 10.1007/s00221-013-3440-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 02/02/2013] [Indexed: 11/25/2022]
|
14
|
Comparison of event-related potentials elicited by cardinal and oblique orientations with broad-band noise stimuli. Vision Res 2012; 60:95-100. [DOI: 10.1016/j.visres.2012.03.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 02/02/2012] [Accepted: 03/15/2012] [Indexed: 11/22/2022]
|
15
|
Koelewijn L, Dumont JR, Muthukumaraswamy SD, Rich AN, Singh KD. Induced and evoked neural correlates of orientation selectivity in human visual cortex. Neuroimage 2011; 54:2983-93. [DOI: 10.1016/j.neuroimage.2010.11.045] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 11/11/2010] [Accepted: 11/12/2010] [Indexed: 11/26/2022] Open
|
16
|
Baker TJ, Norcia AM, Candy TR. Orientation tuning in the visual cortex of 3-month-old human infants. Vision Res 2011; 51:470-8. [PMID: 21236289 DOI: 10.1016/j.visres.2011.01.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Revised: 12/30/2010] [Accepted: 01/04/2011] [Indexed: 10/18/2022]
Abstract
Sensitivity to orientation is critical for making a whole and complete picture of the world. We measured the orientation tuning of mechanisms in the visual cortex of typically developing 3-month-olds and adults using a nonlinear analysis of the two-input steady-state Visually Evoked Potential (VEP). Two gratings, one a fixed test and the other a variable orientation masker were tagged with distinct temporal frequencies and the corresponding evoked responses were measured at the harmonics of the test and masker frequencies and at a frequency equal to the sum of the two stimulus frequencies. The magnitude of the sum frequency component depended strongly on the relative orientation of the test and masker in both infants and adults. The VEP tuning bandwidths of the 3-month-olds measured at the sum frequency were similar to those of adults, suggesting that behavioral immaturities in functions such as orientation discrimination and contour integration may result from other immaturities in long-range lateral projections or feedback mechanisms.
Collapse
Affiliation(s)
- Thomas J Baker
- School of Optometry, Indiana University, Bloomington, IN 47405, USA.
| | | | | |
Collapse
|
17
|
Heinrich SP, Aertsen A, Bach M. Oblique effects beyond low-level visual processing. Vision Res 2008; 48:809-18. [DOI: 10.1016/j.visres.2007.12.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2006] [Revised: 10/04/2007] [Accepted: 12/14/2007] [Indexed: 10/22/2022]
|
18
|
Pei F, Pettet MW, Norcia AM. Sensitivity and configuration-specificity of orientation-defined texture processing in infants and adults. Vision Res 2006; 47:338-48. [PMID: 17188321 PMCID: PMC1994821 DOI: 10.1016/j.visres.2006.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2006] [Revised: 10/01/2006] [Accepted: 10/12/2006] [Indexed: 11/16/2022]
Abstract
Here we use textures made up of widely spaced Gabor patches to compare infant and adult sensitivity to the global organization of the elements comprising the textures. Visual Evoked Potentials (VEPs) were recorded to alterations between random images and images containing varying proportions of patches that were of the same orientation. The patches were placed on rectangular, hexagonal or random lattices. Texture-specific responses were robust in adults and their VEP threshold was reached when 1-17% of the patches had the same orientation in the structured image. Infant thresholds were approximately 20-60%. While infants are capable of detecting the global structure of our textures, their sensitivity is low. In adults we found, unexpectedly, that sensitivity and response gain were higher for horizontal compared to vertical global orientations. Infant sensitivity was the same for the two orientations. Comparable orientation anisotropies have not been previously reported for gratings, suggesting that the Gabor-defined textures are tapping different mechanisms. There were small, but measurable effects of the lattice type in adults, with the rectangular lattice producing the largest responses.
Collapse
Affiliation(s)
- Francesca Pei
- Department of Physiology and Biochemistry, University of Pisa, Italy
| | | | | |
Collapse
|
19
|
Tobimatsu S, Celesia GG. Studies of human visual pathophysiology with visual evoked potentials. Clin Neurophysiol 2006; 117:1414-33. [PMID: 16516551 DOI: 10.1016/j.clinph.2006.01.004] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Revised: 12/28/2005] [Accepted: 01/11/2006] [Indexed: 11/19/2022]
Abstract
Visual evoked potentials (VEPs) offer reproducible and quantitative data on the function of the visual pathways and the visual cortex. Pattern reversal VEPs to full-field stimulation are best suited to evaluate anterior visual pathways while hemi-field stimulation is most effective in the assessment of post-chiasmal function. However, visual information is processed simultaneously via multiple parallel channels and each channel constitutes a set of sequential processes. We outline the major parallel pathways of the visual system from the retina to the primary visual cortex and higher visual areas via lateral geniculate nucleus that receive visual input. There is no best method of stimulus selection, rather visual stimuli and VEPs' recording should be tailored to answer specific clinical and/or research questions. Newly developed techniques that can assess the functions of extrastriate as well as striate cortices are discussed. Finally, an algorithm of sequential steps to evaluate the various levels of visual processing is proposed and its clinical use revisited.
Collapse
Affiliation(s)
- Shozo Tobimatsu
- Department of Clinical Neurophysiology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka 812-8582, Japan.
| | | |
Collapse
|
20
|
Lorteije JAM, Kenemans JL, Jellema T, van der Lubbe RHJ, de Heer F, van Wezel RJA. Delayed Response to Animate Implied Motion in Human Motion Processing Areas. J Cogn Neurosci 2006. [DOI: 10.1162/jocn.2006.18.2.158] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Abstract
Viewing static photographs of objects in motion evokes higher fMRI activation in the human medial temporal complex (MT+) than looking at similar photographs without this implied motion. As MT+ is traditionally thought to be involved in motion perception (and not in form perception), this finding suggests feedback from object-recognition areas onto MT+. To investigate this hypothesis, we recorded extracranial potentials evoked by the sight of photographs of biological agents with and without implied motion. The difference in potential between responses to pictures with and without implied motion was maximal between 260 and 400 msec after stimulus onset. Source analysis of this difference revealed one bilateral, symmetrical dipole pair in the occipital lobe. This area also showed a response to real motion, but approximately 100 msec earlier than the implied motion response. The longer latency of the implied motion response in comparison to the real motion response is consistent with a feedback projection onto MT+ following object recognition in higher-level temporal areas.
Collapse
Affiliation(s)
| | - J. Leon Kenemans
- 1Helmholtz Research Institute, Utrecht University, The Netherlands
| | - Tjeerd Jellema
- 1Helmholtz Research Institute, Utrecht University, The Netherlands
- 2Hull University, United Kingdom
| | | | | | - Richard J. A. van Wezel
- 1Helmholtz Research Institute, Utrecht University, The Netherlands
- 1Helmholtz Research Institute, Utrecht University, The Netherlands
- 2Hull University, United Kingdom
| |
Collapse
|
21
|
Boon MY, Suttle CM, Henry B. Estimating chromatic contrast thresholds from the transient visual evoked potential. Vision Res 2005; 45:2367-83. [PMID: 15979463 DOI: 10.1016/j.visres.2005.02.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2004] [Revised: 02/17/2005] [Accepted: 02/21/2005] [Indexed: 11/21/2022]
Abstract
Chromatic contrast thresholds may be estimated from transient VEPs by measuring the peak-to-peak amplitude at a range of stimulus levels followed by extrapolation to zero amplitude. However, there have been reports of failure of this technique when applied to the transient chromatic VEP due to variability of amplitude, difficulties with component identification and poor correlation of amplitude with stimulus level. The aim of our study was to compare methods of transient VEP chromatic contrast threshold estimation in terms of success rate and comparison with psychophysical threshold. We found each of the methods we investigated to have a high success rate, and in most cases VEP and psychophysical thresholds did not differ significantly.
Collapse
Affiliation(s)
- Mei Ying Boon
- School of Optometry and Vision Science, University of New South Wales, Sydney NSW 2052, Australia.
| | | | | |
Collapse
|
22
|
Lee J, Lee C. Changes in visual motion perception before saccadic eye movements. Vision Res 2005; 45:1447-57. [PMID: 15743614 DOI: 10.1016/j.visres.2004.12.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2004] [Revised: 12/07/2004] [Accepted: 12/20/2004] [Indexed: 11/26/2022]
Abstract
Execution of a saccadic eye movement influences subsequent motion perception [Park, J., Lee, J., & Lee, C. (2001). Non-veridical visual motion perception immediately after saccades. Vision Research, 41, 3751-3761]. In the current study, we determined the pattern of perceptual changes for visual motion presented before saccades. The accuracy of judging the direction of a moving target was variable depending on the direction of target motion. Based on the pattern of judgment errors, the direction associated with no error, or DNE, could be defined. When a moving target was seen by stationary eyes, the DNE was roughly vertical, and the perceptual judgment for adjacent directions was biased away from the vertical direction. When the same visual motion was seen before horizontal saccades, the DNE shifted in the direction of the impending saccade, and the perceptual judgment of adjacent directions was shifted away from the new DNE, thus, shifting the perceived direction of the vertical in the direction opposite to the saccade. These changes improved the accuracy of direction judgment for visual motion in the visual field ipsiversive to impending saccades. In addition to shift of the DNE, perceptual judgment for oblique directions became near veridical before saccades, which we call the anti-oblique effect. These results suggest that motion perception is dynamically and anisotropically modulated at the time of saccades, and the DNE shift may be a part of processes dynamically reallocating computational resources, improving perceptual performance in advance for sensory events to be acquired by impending saccades.
Collapse
Affiliation(s)
- Jungah Lee
- Department of Psychology, Seoul National University, Kwanak, Seoul 151-742, Republic of Korea
| | | |
Collapse
|
23
|
Abstract
The details of oriented visual stimuli are better resolved when they are horizontal or vertical rather than oblique. This "oblique effect" has been confirmed in numerous behavioral studies in humans and to some extent in animals. However, investigations of its neural basis have produced mixed and inconclusive results, presumably due in part to limited sample sizes. We have used a database to analyze a population of 4,418 cells in the cat's striate cortex to determine possible differences as a function of orientation. We find that both the numbers of cells and the widths of orientation tuning vary as a function of preferred orientation. Specifically, more cells prefer horizontal and vertical orientations compared with oblique angles. The largest population of cells is activated by orientations close to horizontal. In addition, orientation tuning widths are most narrow for cells preferring horizontal orientations. These findings are most prominent for simple cells tuned to high spatial frequencies. Complex cells and simple cells tuned to low spatial frequencies do not exhibit these anisotropies. For a subset of simple cells from our population (n = 104), we examined the relative contributions of linear and nonlinear mechanisms in shaping orientation tuning curves. We find that linear contributions alone do not account for the narrower tuning widths at horizontal orientations. By modeling simple cells as linear filters followed by static expansive nonlinearities, our analysis indicates that horizontally tuned cells have a greater nonlinear component than those tuned to other orientations. This suggests that intracortical mechanisms play a major role in shaping the oblique effect.
Collapse
Affiliation(s)
- Baowang Li
- Group in Vision Science, School of Optometry and Helen Wills Neuroscience Institute, University of California, Berkeley, California 94720-2020, USA
| | | | | |
Collapse
|
24
|
|
25
|
Proverbio AM, Esposito P, Zani A. Early involvement of the temporal area in attentional selection of grating orientation: an ERP study. BRAIN RESEARCH. COGNITIVE BRAIN RESEARCH 2002; 13:139-51. [PMID: 11867258 DOI: 10.1016/s0926-6410(01)00103-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The aim of the present study was to investigate the neural mechanisms of stimulus orientation selection in humans by recording event-related potentials (ERPs) of the brain with a 32-channel montage. Stimuli were isoluminant black-and-white gratings (3 cpd) having an orientation of 50, 70, 90, 110 and 130, randomly presented in the foveal portion (2 of visual angle) of the central visual field. The task consisted in selectively attending and responding to one of the five grating orientations, while ignoring the others. ERP results showed that orientation selection affected neural processing starting already at an early post-stimulus latency. The P1 component (80-140 ms) measured at temporal area, which might well be reflecting the activity of the ventral stream (i.e. 'WHAT' system) of the visual pathways, showed an enhanced amplitude for target orientations. These effects increased with progressive neural processing over time as reflected by selection negativity (SN) and P300 components. In addition, both reaction times (RTs) and ERPs showed a strong 'oblique' effect, very probably reflecting the perceptual predominance of orthogonal versus oblique stimulus orientation in the human visual system: RTs were much faster, and SN and P300 components much larger, to gratings presented vertically than in other orientations.
Collapse
Affiliation(s)
- Alice Mado Proverbio
- Department of Psychology, University of Milano-Bicocca, Piazza dell'Ateneo Nuovo, 1, 20126 Milan, Italy.
| | | | | |
Collapse
|
26
|
Abstract
The primary visual cortex (V1) of higher mammals contains maps of stimulus features; how these maps influence vision remains unknown. We have examined the functional significance of an asymmetry in the orientation map in cat V1, i.e., the fact that a larger area of V1 is preferentially activated by vertical and horizontal contours than by contours at oblique orientations. Despite the fact that neurons tuned to cardinal and oblique orientations have indistinguishable tuning characteristics, cardinal neurons remain more stable in their response properties after selective perturbation induced by adaptation. Similarly, human observers report different adaptation-induced changes in orientation tuning between cardinal and oblique axes. We suggest that the larger cortical area devoted to cardinal orientations imposes stability on the processing of cardinal contours during visual perception, by retaining invariant cortical responses along cardinal axes.
Collapse
Affiliation(s)
- V Dragoi
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | | | | |
Collapse
|