Susana Martinez-Conde

Susana Martinez-Conde
State University of New York Downstate Medical Center | SUNY · Department of Ophthalmology

PhD

About

270
Publications
80,189
Reads
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7,743
Citations
Additional affiliations
August 2014 - present
State University of New York Downstate Medical Center
Position
  • Professor (Full)
January 2004 - August 2014
Barrow Neurological Institute
Position
  • Director, Laboratory of Visual Neuroscience

Publications

Publications (270)
Article
Full-text available
Research has not yet quantified the effects of workload or duty hours on the accuracy of radiologists. With the exception of a brief reduction in imaging studies during the 2020 peak of the COVID-19 pandemic, the workload of radiologists in the United States has seen relentless growth in recent years. One concern is that this increased demand could...
Article
Humans perceive millions of colors along three dimensions of color space: hue, lightness, and chroma. A major gap in knowledge is where the brain represents these specific dimensions in cortex, and how they relate to each other. Previous studies have shown that brain areas V4 and the posterior inferotemporal cortex (PIT) are central to computing co...
Article
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Errors in radiologic interpretation are largely the result of failures of perception. This remains true despite the increasing use of computer-aided detection and diagnosis. We surveyed the literature on visual illusions during the viewing of radiologic images. Misperception of anatomical structures is a potential cause of error that can lead to pa...
Article
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For millennia, people have used “averted vision” to improve their detection of faint celestial objects, a technique first documented around 325 BCE. Yet, no studies have assessed gaze location during averted vision to determine what pattern best facilitates perception. Here, we characterized averted vision while recording eye‐positions of dark‐adap...
Article
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Troxler fading, the perceptual disappearance of stationary images upon sustained fixation, is common for objects with equivalent luminance to that of the background. Previous work showed that variations in microsaccadic rates underlie the perceptual vanishing and intensification of simple stimuli, such as Gabor patches. Here, we demonstrate that mi...
Article
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Supported by guidance from training during residency programs, radiologists learn clinically relevant visual features by viewing thousands of medical images. Yet the precise visual features that expert radiologists use in their clinical practice remain unknown. Identifying such features would allow the development of perceptual learning training me...
Article
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In this paper, we outline a method for surgical preparation that allows for the practical planning of a variety of neurosurgeries in NHPs solely using data extracted from magnetic resonance imaging (MRI). This protocol allows for the generation of 3D printed anatomically accurate physical models of the brain and skull, as well as an agarose gel mod...
Article
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Recent technical developments and increased affordability of high-speed eye tracking devices have brought microsaccades to the forefront of research in many areas of sensory, perceptual, and cognitive processes. The present thematic issue on “Microsaccades: Empirical Research and Methodological Advances” invited authors to submit original research...
Article
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Visual scene characteristics have the ability to affect various aspects of saccade and microsaccade dynamics. For example, blank visual scenes are known to elicit diminished saccade and microsaccade production, compared to natural scenes. Similarly, microsaccades are less frequent in the dark. Yet, the extent to which foveal and peripheral visual i...
Article
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Across a wide variety of research environments, the recording of microsaccades and other fixational eye movements has provided insight and solutions into practical problems. Here we review the literature on fixational eye movements—especially microsaccades—in applied and ecologically-valid scenarios. Recent technical advances allow noninvasive fixa...
Article
Full-text available
The integration of synaptic inputs onto dendrites provides the basis for neuronal computation. Whereas recent studies have begun to outline the spatial organization of synaptic inputs on individual neurons, the underlying principles related to the specific neural functions are not well understood. Here we perform two-photon dendritic imaging with a...
Article
Full-text available
As the first step in image interpretation is detection, an error in perception can prematurely end the diagnostic process leading to missed diagnoses. Because perceptual errors of this sort–“failure to detect”–are the most common interpretive error (and cause of litigation) in radiology, understanding the nature of perceptual expertise is essential...
Article
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Video stream: https://vimeo.com/365522806 The human ability for visualization extends far beyond the physical items that surround us. We are able to dismiss the constant influx of photons hitting our retinas, and instead picture the layout of our kindergarten classroom, envision the gently swaying palm trees of our dream vacation, or foresee the f...
Chapter
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There is too much going on around us to see everything at once, or to simultaneously process all the information in our field of view. Instead, we normally direct our gaze to parts of the scene that are particularly meaningful or important. Yet, even when we think that we are keeping our eyes still on an object of interest, our eyes remain in conti...
Article
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Active communication between researchers and society is necessary for the scientific community's involvement in developing science-based policies. This need is recognized by governmental and funding agencies that compel scientists to increase their public engagement and disseminate research findings in an accessible fashion. Storytelling techniques...
Article
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Novel genetically encoded tools and advanced microscopy methods have revolutionized neural circuit analyses in insects and rodents over the last two decades. Whereas numerous technical hurdles originally barred these methodologies from success in nonhuman primates (NHPs), current research has started to overcome those barriers. In some cases, metho...
Article
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The methods of magicians provide powerful tools for enhancing the ecological validity of laboratory studies of attention. The current research borrows a technique from magic to explore the relationship between microsaccades and covert attention under near-natural viewing conditions. We monitored participants’ eye movements as they viewed a magic tr...
Article
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Radiologists rely principally on visual inspection to detect, describe, and classify findings in medical images. As most interpretive errors in radiology are perceptual in nature, understanding the path to radiologic expertise during image analysis is essential to educate future generations of radiologists. We review the perceptual tasks and challe...
Article
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Vasarely’s nested squares illusion shows that the corners of concentric squares, arranged in a gradient of increasing or decreasing luminance, generate illusory “corner-folds,” which appear more salient (either brighter or darker) than the adjacent flat (non- corner) regions of each individual square. The Alternating Brightness Star (ABS) illusion,...
Data
Exact p-values for Fig 4B, corrected for multiple comparisons (Benjamini and Hochberg method). (DOCX)
Data
Correction of eye position signals. (A) Distorted eye position signals (black line) and the grid of candidate locations of the fixation cross (red crosses). (B) Identified fixation locations before correction. (C) Identified fixation locations after correction. (EPS)
Data
Absolute baseline activity. The distributions of absolute baseline activity in response to three visual stimuli conditions (i.e. Square and Edge, Star, and Corners) are shown in box plots, which indicate the maximum, 25 percentile, median, 75 percentile, and the minimum level of absolute baseline activity in each distribution. (EPS)
Data
The ARRIVE guidelines checklist. We followed the ARRIVE (Animal Research: Reporting of In Vivo Experiments) guidelines and the ARRIVE Checklist is available. (DOC)
Data
Clean visual stimuli. (A) Square and Edge. (B) Star. (C) Corners. All stimuli are drawn to scale. (EPS)
Data
Neural responses to corner-folds as a function of latency. Neural responses at the corner-fold midpoints were estimated as described in the Material and Methods, except that we set the conduction latency from retina-to- V1 from 1 ms to 2400 ms, with the associated neural responses peaking around 60 ms. Error bars indicate the SEM (the N are as in F...
Data
Comparison of neural responses at different RMS contrasts along the Edge stimulus with the neural responses to the folds at midpoint. Each row shows the mean difference in response at each angle and RMS contrast with its 95% confidence interval, degrees of freedom (DF), t-statistic and p-value (two sample t-test). (DOCX)
Article
Full-text available
Can the eye movements we make when there is nothing to look at shed light on our cognitive processes? A new study shows that tiny gaze shifts reveal people’s attended locations in memorized—rather than visual—space. The discovery indicates that the oculomotor system is engaged in the focusing of attention within the internal space of memory.
Preprint
Full-text available
The integration of synaptic inputs onto dendrites provides the basis for computation within individual neurons. Whereas recent studies have begun to outline the spatial organization of synaptic inputs on individual neurons, the underlying principles related to the specific neural functions is not well known. Here we performed two-photon dendritic i...
Article
Full-text available
Scientific research on consciousness is critical to multiple scientific, clinical, and ethical issues. The growth of the field could also be beneficial to several areas including neurology and mental health research. To achieve this goal, we need to set funding priorities carefully and address problems such as job creation and potential media misre...
Article
Don't keep gratitude to yourself. You need to express it to reap the wider benefits, finds Susana Martinez-Conde
Article
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The scientific study of consciousness emerged as an organized field of research only a few decades ago. As empirical results have begun to enhance our understanding of consciousness, it is important to find out whether other factors, such as funding for consciousness research and status of consciousness scientists, provide a suitable environment fo...
Preprint
Full-text available
The scientific study of consciousness became an organized field of research less than thirty years ago. Since then, a large number of empirical findings increased our understanding of consciousness. Scientific progress, however, does not only consist on the advancement of knowledge. Increased funding for consciousness research and the rising status...
Article
Full-text available
Whereas optogenetic techniques have proven successful in their ability to manipulate neuronal populations—with high spatial and temporal fidelity—in species ranging from insects to rodents, significant obstacles remain in their application to nonhuman primates (NHPs). Robust optogenetics-activated behavior and long-term monitoring of target neurons...
Data
Sparse labeling cells in the surrounding regions away from injection centers exhibited membrane localized expression pattern of C1V1. C1V1, ChR1/VChR1. (TIF)
Data
Long-term stability of AOI in V1 of monkey M3. (A) Left, 2P images of a V1 neuronal population on Day 28 and Day 62 after virus injection. Right, the same neuronal population was activated with visual stimuli on Day 28 and Day 62. (B) Left, spatial organization of orientation selectivity in V1 on Day 28 and Day 62. Each color corresponds to the mat...
Data
Synchronization control of 2P imaging and 1P photostimulation. (A) 2P image of a cortical area without 532-nm photostimulation. (B) The same cortical area imaged during continuous wide-field photostimulation, resulting in PMT saturation. (C) We powered down the photostimulation whenever the 2P imaging targeted the central 75% of the FOV, allowing t...
Data
V1 neuronal population responses to oriented grating stimuli. V1, primary visual cortex. (MOV)
Data
Responses of neurons to photostimulation at different intensities, from the 30 neurons recorded in Fig 1F, on Day 158 post-infection. (TIF)
Data
Orientation tuning and spatial organization in macaque V1. (A) Left, orientation tuning curves of neurons (N = 148) responding to orientation-grating stimuli (P < 0.05, ANOVA across six orientations) on Day 158. The orange curve is the average response from all selected neurons (grey), and preferred orientations were rotated to aligned to zero degr...
Data
Example cells in 5 evenly spaced layers, corresponding to plots in Fig 2F. Differential images (stimulated baseline [F-F0]) under wide-field photostimulation. (TIF)
Data
Spatial precision of 2P stimulation after calibration. (A) 5 × 5 grid locations used for calibration. (B) After calibration, a N-type dot array was precisely burned by series of spiral scanning laser (red, 5 rotations, 1.2 expansion rate, 0.01 pixel/μs, and 10 repetitions). 2P, two-photon. (TIF)
Article
Full-text available
When we explore a static visual scene, our eyes move in a sequence of fast eye movements called saccades, which are separated by fixation periods of relative eye stability. Based on uncertain sensory and cognitive inputs, the oculomotor system must decide, at every moment, whether to initiate a saccade or to remain in the fixation state. Even when...
Article
Full-text available
In the late 1970s, key discoveries in neurophysiology, psychophysics, computer vision, and image processing had reached a tipping point that would shape visual science for decades to come. David Marr and Ellen Hildreth's 'Theory of edge detection', published in 1980, set out to integrate the newly available wealth of data from behavioral, physiolog...
Article
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Microsaccade research has recently reached a critical mass of studies that allows, for the first time, a comprehensive review of how microsaccadic dynamics change in neurological and ophthalmic disease. We discuss the various pathological conditions that affect microsaccades, their impact on microsaccadic and other fixational eye movement dynamics,...
Preprint
Full-text available
Whereas optogenetic techniques have proven successful in their ability to manipulate neuronal populations in species ranging from insects to rodents—with high spatial and temporal fidelity—significant obstacles remain in their application to non-human primates (NHPs). Robust optogenetics-activated behavior and long-term noninvasive monitoring of ta...
Article
The Human Visual System appears to be using a low number of sensors for image capturing, and furthermore, regarding the physical dimensions of cones—photoreceptors responsible for the sharp central vision—we may realize that these sensors are of a relatively small size and area. Nonetheless, the human eye is capable of resolving fine details thanks...
Article
Most of us really don't understand how mirrors work, which makes for some fun reflective deception
Article
Full-text available
Scientists have pondered the perceptual effects of ocular motion, and those of its counterpart, ocular stillness, for over 200 years. The unremitting ‘trembling of the eye’ that occurs even during gaze fixation was first noted by Jurin in 1738. In 1794, Erasmus Darwin documented that gaze fixation produces perceptual fading, a phenomenon rediscover...
Article
Full-text available
The human eye appears to be using a low number of sensors for image capturing. Furthermore, regarding the physical dimensions of cones-photoreceptors responsible for the sharp central vision-, we may realize that these sensors are of a relatively small size and area. Nonetheless, the eye is capable to obtain high resolution images due to visual hyp...
Article
Full-text available
Seizure-driven brain damage in epilepsy accumulates over time, especially in the hippocampus, which can lead to sclerosis, cognitive decline, and death. Excitotoxicity is the prevalent model to explain ictal neurodegeneration. Current labeling technologies cannot distinguish between excitotoxicity and hypoxia, however, because they share common mol...
Article
To avoid or at least control conflict, militaries often play tricks on their opponents' perceptions
Article
Cognitive scientists and magicians know that free choice can be an illusion
Article
Commonly conflated with sleepiness, fatigue is a distinct multidimensional condition with physical and mental effects. Fatigue in health care providers and any secondary effects on patient care are an important societal concern. As medical image interpretation is highly dependent on visual input, visual fatigue is of particular interest to radiolog...
Article
Fixational eye movements (FEM), including microsaccades, drift, and tremor, shift our eye position during ocular fixation, producing retinal motion that is thought to help visibility by counteracting neural adaptation to unchanging stimulation. Yet, how each FEM type influences this process is still debated. Recent studies found little to no relati...