1
|
Lu Y, Zou L, Chen Y, Mao Y, Zhu J, Lin W, Wu D, Chen R, Qu J, Zhou J. Rapid Alternate Flicker Modulates Binocular Interaction in Adults With Abnormal Binocular Vision. Invest Ophthalmol Vis Sci 2023; 64:15. [PMID: 36786740 PMCID: PMC9932553 DOI: 10.1167/iovs.64.2.15] [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] [Indexed: 02/15/2023] Open
Abstract
Purpose The current understanding of binocular processing is primarily derived from static spatial visual perception: this leaves the role of temporal information unclear. In this study, we addressed this gap by testing the effect of alternating flicker on binocular information processing in adults with abnormal binocular vision. Our goal was to determine which temporal frequency optimally balanced input from both eyes. Methods We took measurements in four groups of human adults: 10 normal adults with the individual's nondominant eye covered by a 2% neutral density filter (aged 25.60 ± 1.43 years, experiment 1), 9 nonamblyopic anisometropes (aged 24.33 ± 1.66 years, experiment 2), 7 amblyopes (aged 26.5 ± 1.64 years, experiment 3), and 7 treated amblyopes (aged 24 ± 3.21 years, experiment 4). The balance point (BP), where participants' two eyes are equally effective, was measured using a binocular orientation combination task at four spatial frequencies (SFs; 0.5-4 c/d) and five temporal frequencies (TFs; baseline and 4, 7, 10, and 15 Hz). Its log transformation |logBP| was taken into further analysis. Results We observed clear U-shaped temporal tuning of the |logBP| for the entire range of TFs (that we measured: trough occurred at 7 Hz). This pattern occurred and was significant in all four groups (P < 0.001). In addition, the effect of SFs on |logBP| was significant in normal, amblyopic, and treated amblyopic groups (all P < 0.001) and was marginally significant in the nonamblyopic anisometropic group (P = 0.086). Conclusions Alternating flicker around 7 Hz may be the optimal temporal frequency for balancing eyes in human adults with binocular imbalance.
Collapse
Affiliation(s)
- Yiqiu Lu
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China
| | - Liying Zou
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China
| | - Yiya Chen
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China
| | - Yu Mao
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China
| | - Jinli Zhu
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China
| | - Wenman Lin
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China
| | - Dingqiang Wu
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China
| | - Ruyin Chen
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China
| | - Jia Qu
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China,Oujiang Laboratory, Zhejiang Lab for Regenerative Medicine, Vision and Brain Health, Wenzhou, China
| | - Jiawei Zhou
- State Key Laboratory of Ophthalmology, Optometry and Visual Science and National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital Wenzhou Medical University, Wenzhou, China
| |
Collapse
|
2
|
The channel for detecting contrast modulation also responds to density modulation (or vice versa). Vision Res 2021; 192:107948. [PMID: 34883365 DOI: 10.1016/j.visres.2021.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 08/14/2021] [Accepted: 08/19/2021] [Indexed: 11/20/2022]
Abstract
In textures composed of black and white dots, we modulated dot density and/or dot contrast in one direction of visual space. Just as Mulligan and MacLeod (Vision Research 28 (1988) 503-519) found a strong reciprocity between density and luminance for dots viewed against a darker background, we found a strong reciprocity between density and contrast: detection thresholds for in-phase modulations of density and contrast were 30% - 55% lower than detection thresholds for density and contrast modulations that were 180° out of phase. These findings support the existence of at least one psychophysical channel that is excited by both density modulations and contrast modulations. A good, quantitative fit to our data can be obtained with a two-channel model.
Collapse
|
3
|
Abstract
Whereas psychophysicists may formulate hypotheses about appearance, they can only measure performance. Bias and imprecision in psychophysical data need not necessarily reflect bias and imprecision in perception. Sensory systems may exaggerate the differences between each item and its neighbors in an ensemble. Alternatively, sensory systems may homogenize the ensemble, thereby removing any apparent differences between neighboring items. Ensemble perception may be involuntary when observers attempt to report the identities of individual items. Conversely, when asked to make a (voluntary) decision about the ensemble as a whole, observers may find it very difficult to compute statistics that are based on more than a very small number of individual items. Modeling decisions about prothetic continua, such as size and contrast, can be tricky because sensory signals may be distorted before and/or after voluntarily computing ensemble statistics. With metathetic continua, such as spatial orientation, distortion is less problematic; physically vertical things necessarily appear close to vertical and physically horizontal things necessarily appear close to horizontal. Decision processes are corrupted by noise that, like distortion, may be added to sensory signals prior to and/or after voluntarily computing ensemble statistics.
Collapse
|
4
|
Devine CA, Gaffney C, Loughnane GM, Kelly SP, O'Connell RG. The role of premature evidence accumulation in making difficult perceptual decisions under temporal uncertainty. eLife 2019; 8:e48526. [PMID: 31774396 PMCID: PMC6904213 DOI: 10.7554/elife.48526] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 11/26/2019] [Indexed: 12/31/2022] Open
Abstract
The computations and neural processes underpinning decision making have primarily been investigated using highly simplified tasks in which stimulus onsets cue observers to start accumulating choice-relevant information. Yet, in daily life we are rarely afforded the luxury of knowing precisely when choice-relevant information will appear. Here, we examined neural indices of decision formation while subjects discriminated subtle stimulus feature changes whose timing relative to stimulus onset ('foreperiod') was uncertain. Joint analysis of behavioural error patterns and neural decision signal dynamics indicated that subjects systematically began the accumulation process before any informative evidence was presented, and further, that accumulation onset timing varied systematically as a function of the foreperiod of the preceding trial. These results suggest that the brain can adjust to temporal uncertainty by strategically modulating accumulation onset timing according to statistical regularities in the temporal structure of the sensory environment with particular emphasis on recent experience.
Collapse
Affiliation(s)
- Ciara A Devine
- Trinity College Institute of Neuroscience and School of PsychologyThe University of Dublin, Trinity CollegeDublinIreland
| | - Christine Gaffney
- Trinity College Institute of Neuroscience and School of PsychologyThe University of Dublin, Trinity CollegeDublinIreland
| | | | - Simon P Kelly
- School of Electrical and Electronic Engineering and UCD Centre for Biomedical EngineeringUniversity College DublinDublinIreland
| | - Redmond G O'Connell
- Trinity College Institute of Neuroscience and School of PsychologyThe University of Dublin, Trinity CollegeDublinIreland
| |
Collapse
|
5
|
Patrick JA, Roach NW, McGraw PV. Temporal modulation improves dynamic peripheral acuity. J Vis 2019; 19:12. [PMID: 31747690 PMCID: PMC6871547 DOI: 10.1167/19.13.12] [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] [Indexed: 11/24/2022] Open
Abstract
Macular degeneration and related visual disorders greatly limit foveal function, resulting in reliance on the peripheral retina for tasks requiring fine spatial vision. Here we investigate stimulus manipulations intended to maximize peripheral acuity for dynamic targets. Acuity was measured using a single interval orientation discrimination task at 10° eccentricity. Two types of image motion were investigated along with two different forms of temporal manipulation. Smooth object motion was generated by translating targets along an isoeccentric path at a constant speed (0-20°/s). Ocular motion was simulated by jittering target location using previously recorded fixational eye movement data, amplified by a variable gain factor (0-8). In one stimulus manipulation, the sequence was temporally subsampled by displaying the target on an evenly spaced subset of video frames. In the other, the contrast polarity of the stimulus was reversed at a variable rate. We found that threshold under object motion was improved at all speeds by reversing contrast polarity, while temporal subsampling improved resolution at high speeds but impaired performance at low speeds. With simulated ocular motion, thresholds were consistently improved by contrast polarity reversal, but impaired by temporal subsampling. We find that contrast polarity reversal and temporal subsampling produce differential effects on peripheral acuity. Applying contrast polarity reversal may offer a relatively simple image manipulation that could enhance visual performance in individuals with central vision loss.
Collapse
Affiliation(s)
- Jonathan A Patrick
- Nottingham Visual Neuroscience, The University of Nottingham, Nottingham, UK
| | - Neil W Roach
- Nottingham Visual Neuroscience, The University of Nottingham, Nottingham, UK
| | - Paul V McGraw
- Nottingham Visual Neuroscience, The University of Nottingham, Nottingham, UK
| |
Collapse
|