Untrained Eye Research Articles

Volumetric Imaging of the Malar Fat Pad and Implications for Facial Plastic Surgery

Volumetric Imaging of the Malar Fat Pad and Implications for Facial Plastic Surgery

Perceptual Learning and Dynamic Changes in Primary Visual Cortex

Perceptual learning is the improved performance that follows practice in a perceptual task. In this issue of Neuron, Yotsumoto et al. use fMRI to show that stimuli presented at the location used in training initially evoke greater activation in primary visual cortex than stimuli presented elsewhere, but this difference disappears once learning asymptotes.

Intraindividual Comparison of the Effect of Training on Visual Performance With ReSTOR and Tecnis Diffractive Multifocal IOLs

Several studies have shown that after multifocal intraocular lens (IOL) implantation visual function improves gradually over a period of several months. To accelerate this learning process, a prospective, intraindividual comparative study was performed to investigate the efficacy of a special visual training program on the postoperative visual performance. Sixteen patients with bilateral phacoemulsification and multifocal IOL implantation in both eyes (Alcon ReSTOR [n = 8] and AMO Tecnis ZM900 [n = 81) received computer-based visual training 6 weeks postoperatively based on the concept of perceptual learning of discrimination line orientations. The training was performed over 2 weeks in six sessions in one eye of each patient. The untrained fellow eye served as control. Before and after the training period and at 6 months, orientation visual acuity, distance visual acuity, contrast sensitivity, and near visual acuity for different contrast levels were assessed. After 2 weeks of training, the mean improvement of orientation visual acuity in the trained eyes was 82%, which was significantly higher than the control eyes (P < .001). Contrast sensitivity and near vision under different contrast levels showed a significant benefit of training. The superior function of the trained eyes was still present at 6 months. Visual performance after multifocal IOL implantation can be significantly accelerated by a specific 2-week training program. This effect is sustained over a 6-month period.

A new device for collecting saliva for cortisol determination

Saliva for measurement of cortisol is generally sampled by swabbing the mouth with a cotton roll, but this method has drawbacks. In the present study, we evaluated the use of an eye sponge as an oral collection device for saliva cortisol. The eye sponge was compared with commercial cotton rolls, and tested for use in infants as well as adults. Our results show that the eye sponge has adequate cortisol recoveries, even after samples have been kept at 4-8 degrees C for up to a week. In adults, volumes of 200-250 microl are obtained without problem; although smaller volumes are obtained in young infants, they are sufficient for assays requiring only 50-100 microl of saliva. In conclusion, the eye sponge is a valid and adequate collection device for saliva cortisol. Additional advantages as compared to cotton rolls are: more comfortable sampling, tastelessness, no need to manipulate the absorbing material, and the ease with which the untrained eye can determine that enough saliva has been collected.

Video in science. Protocol videos: the implications for research and society.

The Chinese folktale, Three Blind Men and an Elephant , is more than 2,000 years old. Three blind men approached an elephant and tried to describe it. The first man felt the elephant's ear and decided that it was like a fan. The second man touched the elephant's knee and decided that it was like a tree. The third man held the elephant's trunk and concluded that it was like a snake. They could not agree on what an elephant is really like (Kuo & Kuo, 1976). If each of the three men had felt the whole of the elephant, or at least experienced each of the three parts themselves, they would have gained a better idea of what animal they were trying to describe. Scientists, like the blind men, often have too narrow a focus when thinking about their field of research or particular topics. To obtain a larger, more complete picture—to understand what the ‘elephant’ is—they need as much information as possible. One way of achieving this is to take advantage of new technologies, such as video, and use it to communicate scientific methods, protocols and results. Here, I describe the possible advantages of using video to communicate scientific protocols instead of verbal descriptions, and highlight some further benefits of such an approach, in particular in educational and outreach programmes. Visual information is fundamental to communication. As humans, we have relied on our visual perception of the world to convey ideas, feelings and images ever since our ancestors started painting animals on cave walls thousands of years ago. Drawings, paintings, photography, film, television, analogue and digital video, computer‐generated images and the Internet have all further increased and enhanced the use of images to communicate information—not just in general, but specifically with regard to scientific ideas, results and communication. …

EMPOP—A forensic mtDNA database

Mitochondrial DNA databases stand as the basis for frequency estimations of mtDNA sequences that became relevant in a case. The establishment of mtDNA databases sounds trivial; however, it has been shown in the past that this undertaking is prone to error for several reasons, particularly human error. We have established a concept for mtDNA data generation, analysis, transfer and quality control that meets forensic standards. Due to the complexity of mtDNA population data tables it is often difficult if not impossible to detect errors, especially for the untrained eye. We developed software based on quasi-median network analysis that visualizes mtDNA data tables and thus signposts sequencing, interpretation and transcription errors. The mtDNA data ( N = 5173; release 1) are stored and made publicly available via the Internet in the form of the EDNAP mtDNA Population Database, short EMPOP. This website also facilitates quasi-median network analysis and provides results that can be used to check the quality of mtDNA sequence data. EMPOP has been launched on 16 October 2006 and is since then available at http://www.empop.org.

The extent to which the rise in the worship of images in the late Middle Ages was influenced by contemporary theories of vision

There are several ways whereby medieval theories of vision may have contributed to the rise of practices some saw as idolatrous. A feature of much medieval art is the rise of naturalistic representation. This process was facilitated by the use of linear perspective, based ultimately on Euclid's visual cone. We are told its application led viewers to confuse a representation with its object. The theory of extramission influenced medieval piety profoundly. First, by suggesting that the eye emits a ray and ‘touches’ its object, it led worshippers to believe that seeing the Eucharistic host had a salvific effect. This may have led them to think that seeing images of saints or God had a similar effect. Second, by implying that the subject was active in the process of seeing, it underpinned Augustine's theory of vision, whereby one trained the eye to access the invisible through the visible. However, as he was aware, the untrained eye could linger on physical objects and want to possess them. Finally, there was much debate about how visual information was mediated. Some argued that it was transmitted by intermediate bodies. The parallels between their language and that used by iconophobes to describe the images they rejected are striking and merit further investigation. Others argued that the viewer had direct access to the object. This understanding, when combined with the idea that seeing equates to knowing, may have led worshippers to believe that seeing an image of God meant they might in some sense know him.

Primary Care Evaluation of the Nose and Paranasal Sinuses

Primary Care Evaluation of the Nose and Paranasal Sinuses

Identification of contrast-defined letters benefits from perceptual learning in adults with amblyopia

Amblyopes show specific deficits in processing second-order spatial information (e.g. Wong, Levi, & McGraw (2001). Is second-order spatial loss in amblyopia explained by the loss of first-order spatial input? Vision Research, 41, 2951–2960). Recent work suggests there is a significant degree of plasticity in the visual pathway that processes first-order spatial information in adults with amblyopia. In this study, we asked whether or not there is similar plasticity in the ability to process second-order spatial information in adults with amblyopia. Ten adult observers with amblyopia (five strabismic, four anisometropic and one mixed) were trained to identify contrast-defined (second-order) letters using their amblyopic eyes. Before and after training, we determined observers’ contrast thresholds for identifying luminance-defined (first-order) and contrast-defined letters, separately for the non-amblyopic and amblyopic eyes. Following training, eight of the 10 observers showed a significant reduction in contrast thresholds for identifying contrast-defined letters with the amblyopic eye. Five of these observers also showed a partial transfer of improvement to their fellow untrained non-amblyopic eye for identifying contrast-defined letters. There was a small but statistically significant transfer to the untrained task of identifying luminance-defined letters in the same trained eye. Similar to first-order spatial tasks, adults with amblyopia benefit from perceptual learning for identifying contrast-defined letters in their amblyopic eyes, suggesting a sizeable degree of plasticity in the visual pathway for processing second-order spatial information.

Creating Possibilities: Embedding Research into Creative Writing

world's knowledge, he told me. Gag gifts are a staple in my family around Christmas, so I waited for the explanation. You see, he said, that's no ordinary stick. To the untrained eye it may look like an ordinary stick, but believe me, it's not. See that notch in the side of that there stick? Well, that notch is in the exact perfect spot on a stick that is the exact perfect length. If you turn that notch into a fraction and you turn that fraction into a decimal, you end up with a number. And not just any number, the exact perfect number that is a code for every piece of literature ever written.

Learning to identify contrast-defined letters in peripheral vision

Performance for identifying luminance-defined letters in peripheral vision improves with training. The purpose of the present study was to examine whether performance for identifying contrast-defined letters also improves with training in peripheral vision, and whether any improvement transfers to luminance-defined letters. Eight observers were trained to identify contrast-defined letters presented singly at 10° eccentricity in the inferior visual field. Before and after training, we measured observers’ thresholds for identifying luminance-defined and contrast-defined letters, embedded within a field of white luminance noise (maximum luminance contrast = 0, 0.25, and 0.5), at the same eccentric location. Each training session consisted of 10 blocks (100 trials per block) of identifying contrast-defined letters at a background noise contrast of 0.5. Letters ( x-height = 4.2°) were the 26 lowercase letters of the Times-Roman alphabet. Luminance-defined letters were generated by introducing a luminance difference between the stimulus letter and its mid-gray background. The background noise covered both the letter and its background. Contrast-defined letters were generated by introducing a differential noise contrast between the group of pixels that made up the stimulus letter and the group of pixels that made up the background. Following training, observers showed a significant reduction in threshold for identifying contrast-defined letters ( p < 0.0001). Averaged across observers and background noise contrasts, the reduction was 25.8%, with the greatest reduction (32%) occurring at the trained background noise contrast. There was virtually no transfer of improvement to luminance-defined letters, or to an untrained letter size (2× original), or an untrained retinal location (10° superior field). In contrast, learning transferred completely to the untrained contralateral eye. Our results show that training improves performance for identifying contrast-defined letters in peripheral vision. This perceptual learning effect seems to be stimulus-specific, as it shows no transfer to the identification of luminance-defined letters. The complete interocular transfer, and the retinotopic (retinal location) and size specificity of the learning effect are consistent with the properties of neurons in early visual area V2.

Learning to identify contrast-defined letters in peripheral vision

Performance for identifying luminance-defined letters in peripheral vision improves with training. The purpose of the present study was to examine whether performance for identifying contrast-defined letters also improves with training in peripheral vision, and whether any improvement transfers to luminance-defined letters. Eight observers were trained to identify contrast-defined letters presented singly at 10 degrees eccentricity in the inferior visual field. Before and after training, we measured observers' thresholds for identifying luminance-defined and contrast-defined letters, embedded within a field of white luminance noise (maximum luminance contrast=0, 0.25, and 0.5), at the same eccentric location. Each training session consisted of 10 blocks (100 trials per block) of identifying contrast-defined letters at a background noise contrast of 0.5. Letters (x-height=4.2 degrees) were the 26 lowercase letters of the Times-Roman alphabet. Luminance-defined letters were generated by introducing a luminance difference between the stimulus letter and its mid-gray background. The background noise covered both the letter and its background. Contrast-defined letters were generated by introducing a differential noise contrast between the group of pixels that made up the stimulus letter and the group of pixels that made up the background. Following training, observers showed a significant reduction in threshold for identifying contrast-defined letters (p<0.0001). Averaged across observers and background noise contrasts, the reduction was 25.8%, with the greatest reduction (32%) occurring at the trained background noise contrast. There was virtually no transfer of improvement to luminance-defined letters, or to an untrained letter size (2 x original), or an untrained retinal location (10 degrees superior field). In contrast, learning transferred completely to the untrained contralateral eye. Our results show that training improves performance for identifying contrast-defined letters in peripheral vision. This perceptual learning effect seems to be stimulus-specific, as it shows no transfer to the identification of luminance-defined letters. The complete interocular transfer, and the retinotopic (retinal location) and size specificity of the learning effect are consistent with the properties of neurons in early visual area V2.

Perceptual learning of Gabor orientation identification in visual periphery: Complete inter-ocular transfer of learning mechanisms

We combined the external noise paradigm, the Perceptual Template Model approach, and transfer tests to investigate the mechanisms and eye-specificity of perceptual learning of Gabor orientation in visual periphery. Coupled with a fixation task, discriminating a 5 from an S in a rapid small character string at fixation, contrast thresholds were estimated for each of eight external noise levels at two performance criteria using 3/1 and 2/1 staircases. Perceptual learning in one eye was measured over 10 practice sessions, followed by five sessions of practice in the new eye to assess transfer. We found that monocular learning improved performance (reduced contrast thresholds) with virtually equal magnitude across a wide range of external noise levels with no significant change in central task performance. Based on measurements of learning effects at two performance criterion levels, we identified a mixture of stimulus enhancement and external noise exclusion as the mechanism of perceptual learning underlying the observed improvements. Perceptual learning in the trained eye generalized completely to the untrained eye. We related the transfer patterns to known physiology and psychophysics on orientation direction coding.

Independent perceptual learning in monocular and binocular motion systems.

Eye-transfer tests, external noise manipulations, and observer models were used to systematically characterize learning mechanisms in judging motion direction of moving objects in visual periphery (Experiment 1) and fovea (Experiment 2) and to investigate the degree of transfer of the learning mechanisms from trained to untrained eyes. Perceptual learning in one eye was measured over 10 practice sessions. Subsequent learning in the untrained eye was assessed in five transfer sessions. We characterized the magnitude of transfer of each learning mechanism to the untrained eye by separately analyzing the magnitude of subsequent learning in low and high external noise conditions. In both experiments, we found that learning in the trained eye reduced contrast thresholds uniformly across all of the external noise levels: 47 +/- 10% and 62 +/- 8% in experiments 1 and 2, respectively. Two mechanisms, stimulus enhancement and template retuning, accounted for the observed performance improvements. The degree of transfer to the untrained eye depended on the amount of external noise added to the signal stimuli: In high external noise conditions, learning transferred completely to the untrained eye in both experiments. In low external noise conditions, there was only partial transfer of learning: 63% in experiment 1 and 54% in experiment 2. The results suggest that template retuning, which is effective in high external noise conditions, is mostly binocular, whereas stimulus enhancement, which is effective in low external noise displays, is largely monocular. The two independent mechanisms underlie perceptual learning of motion direction identification in monocular and binocular motion systems.

The time course and specificity of perceptual deterioration.

Repeated within-day testing on a texture discrimination task leads to retinotopically specific decreases in performance. Although perceptual learning has been shown to be highly specific to the retinotopic location and characteristics of the trained stimulus, the specificity of perceptual deterioration has not been studied. We investigated the similarities between learning and deterioration by examining whether deterioration transfers to new distractor or target orientations or to the untrained eye. Participants performed a texture discrimination task in three one-hour sessions. We tested the specificity of deterioration in the final session by switching either the orientation of the background or the target elements by 90 degrees. We found that performance deteriorated steadily both within and across the first two sessions and was specific to the target but not the distractor orientation. In a separate experiment, we found that deterioration transferred to the untrained eye. Changes in performance were independent of reported sleepiness and awareness of stimulus changes, arguing against the possibility that perceptual deterioration is due to general fatigue. Rather, we hypothesize that perceptual deterioration may be caused by changes in the ability for attention to selectively enhance the responses of relatively low-level orientation-selective sensory neurons, possibly within the primary visual cortex. Further, the differences in specificity profiles between learning and deterioration suggest separate underlying mechanisms that occur within the same cortical area.

Rethinking Disorders of Consciousness: New Research and Its Implications

Rethinking Disorders of Consciousness:New Research and Its Implications Joseph J. Fins (bio) Over the past several years, deciding whether to withdraw life-sustaining therapy from patients who have sustained severe brain injuries has become much more difficult. The problem is not the religious fundamentalism that infused the debate over the care of Terry Schiavo, the Florida woman in a permanent vegetative state whose case has drawn national attention. Rather, the difficulty stems from emerging knowledge about the diagnosis and physiology of brain injury and recovery. The advent of more sophisticated neuroimaging techniques like MRI and PET scans, in tandem with electrophysiologic and observational studies of brain-injured patients, have led to an effort to differentiate disorders of consciousness more precisely. The crude categories that have informed clinical practice for a quarter century are becoming obsolete. It used to be enough for a neurologist or neurosurgeon to write a note in the chart grimly recording the patient's neurological exam and then concluding with the global statement, "no hope for meaningful recovery." It can no longer be so simple. With a better understanding of brain injury and mechanisms of recovery, we should be suspicious of blanket statements that might, we now believe, obscure important differences among different patients' prospects for recovery, although even those patients we now think may recover may still be left with profound and perhaps intolerable burdens of disability. Recovery from coma depends on a patient's age, the site of injury, and whether the damage was done by trauma, anoxia (oxygen deprivation), or other processes. The most severe brain injuries may lead to brain death. If patients survive and begin to recover from coma, they often first enter into the vegetative state, first described by Bryan Jennett and my teacher, Fred Plum, in 1972. The vegetative state is a paradoxical state of "wakeful unresponsiveness" in which the eyes are open but there is no awareness of self or environment. When a vegetative state continues beyond thirty days, it is described as "persistent." A vegetative state is generally considered permanent three months after anoxic injury and twelve months after trauma. All of this is news since I went to medical school. I was taught that the vegetative state was immutable and fixed. Vegetative brains were, if I recall the phrase correctly, "gelatinous gels." The futility of this brain state was the basis for the establishment of the right to die in cases like Quinlan and Cruzan. Recent studies have shown, however, that patients can regain some evidence of consciousness before the vegetative state becomes permanent. In the window between the persistent and permanent vegetative state, patients can progress to what has been described as the "minimally conscious state" (MCS). Unlike vegetative patients, the minimally conscious demonstrate unequivocal, but fluctuating, evidence of awareness of self and the environment. The natural history of MCS patients is not yet known. Near the upper boundary of this category, patients may say words or phrases and gesture. They also may show evidence of memory, attention, and intention. Patients are considered to have "emerged" from MCS only when they can reliably and consistently communicate. Unfortunately, all of this is easier to explain in theory than to observe in practice. First and foremost is the challenge of diagnosis. To the untrained eye, MCS patients may appear very similar to those who are vegetative. These diagnoses can be confused and conflated and in the earlier phases of illness need to be considered very carefully in the context of the mechanism of injury. In a patient with non-anoxic injury, even small gains beyond the vegetative level may herald the potential for significant further recovery. Some recent studies suggest that the diagnostic distinction between MCS and PVS is missed by neurologists at rates that would be intolerable in other clinical domains. To be fair, however, a neurologist acting in good faith might examine an MCS patient when his level of arousal was low and elicit an exam that is indistinguishable from a vegetative patient. But there is another sort of diagnostic error that occurs when the objectivity of diagnosis is infiltrated by value judgments. Instead of dealing with the moral ambiguity associated with balancing the burdens...

Using Focus Groups to Conduct Business Communication Research

Keywords: focus groups; qualitative research; communication; culture; protocol At the heart of most qualitative research is an effort to better understand peoples' interpretations of their experiences; in effect, to address the question What is going on here? One approach for gathering this kind of qualitative data is using focus methodology. Focus methodology is a qualitative data gathering approach that takes advantage of structured interviewing techniques performed in a setting (Fontana & Frey, 1994). Unlike more traditional one-on-one interviewing, the focus approach encourages discussion among members, and this interaction tends to stimulate ideas that would not have been available otherwise (Morgan, 1988). The dynamic interplay generated among members can provide rich, descriptive information offered from the respondents' viewpoints. As such, focus methodology offers an excellent way for researchers to examine the underlying logic used by and the kind of evidence brought to bear by participants on a given situation or product (Lindlof, 1995). A search of research data collections (e.g., Sociological Abstracts and Psychological Abstracts) reveals that only a few studies were published in the 1980s that report using a focus approach. However, by the end of the following decade, more than 200 studies were published that apparently use focus groups (Morgan, 2002). Clearly, focus methodology has emerged as an important research tool employed by many academic disciplines, including marketing, public policy, strategic planning, and communication (Luntz, 1994; R. Myers, 2002; Rook, 2003). One aspect of the focus methodology that makes it so appealing across many disciplines is that it can lead to theory/knowledge application tested quantitatively (Geroy, Jankovich, & Wright, 1997). Common knowledge and anecdotal evidence suggest that business communication practitioners often employ focus methodologies as a means of collecting information about a product or service. Yet surprisingly, few business communication scholars have reported the use of focus groups in their research. In fact, little focus research has been reported in the business communication research literature. For instance, the special issue of the Journal of Business Communication (Livesey, 2002) addressing qualitative research methodologies does not include an examination of focus groups. In an effort to close this apparent knowledge gap and to encourage business communication scholars to consider the approach as an option in their research, the present commentary reviews the relevant research and practitioner literature and then offers an illustration of how focus groups can be used in business communication scholarship. FOCUS GROUP RESEARCH Goldman (1962) referred to focus groups as group depth (p. 61). The elements of the definition illuminate the approach: A is a number of people who interact and who have a common interest; depth refers to profound information gathered, more so than individual interviews; interview refers to the presence of a moderator; and focus implies a limit to the issues discussed. Focus groups rely heavily on member interaction to stimulate ideas rather than on the more familiar and linear question-and-answer format used in one-on-one interviews (Herndon, 2001). Indeed, Lederman (1990) and Morgan (1988) suggested that the synergistic effect generated by focus groups can be far more revealing than the sum of individual interviews. The interaction that takes place among members that produces such dynamic synergy and rich information can look chaotic to the untrained eye. Yet the researcher/moderator provides the underlying structure that guides the interaction (Herndon, 2001). Focus groups are, in effect, a structured approach for eliciting unstructured discussion. Furthermore, the safety provided in a often allows the participants to share information and insights that might never emerge in other settings (McCracken, 1988). …

Acute Bovine Laminitis: A New Induction Model Using Alimentary Oligofructose Overload

Twelve dairy heifers were used to examine the clinical response of an alimentary oligofructose overload. Six animals were divided into 3 subgroups, and each was given a bolus dose of 13, 17, or 21 g/kg of oligofructose orally. The control group (n = 6) was sham-treated with tap water. Signs of lameness, cardiovascular function, and gastrointestinal function were monitored every 6h during development of rumen acidosis. The heifers were euthanized 48 and 72h after administration of oligofructose. All animals given oligofructose developed depression, anorexia, and diarrhea 9 to 39h after receiving oligofructose. By 33 to 45h after treatment, the feces returned to normal consistency and the heifers began eating again. Animals given oligofructose developed transient fever, severe metabolic acidosis, and moderate dehydration, which were alleviated by supportive therapy. Four of 6 animals given oligofructose displayed clinical signs of laminitis starting 39 to 45h after receiving oligofructose and lasting until euthanasia. The lameness was obvious, but could easily be overlooked by the untrained eye, because the heifers continued to stand and walk, and did not interrupt their eating behavior. No positive pain reactions or lameness were seen in control animals. Based on these results, we conclude that an alimentary oligofructose overload is able to induce signs of acute laminitis in cattle. This model offers a new method, which can be used in further investigation of the pathogenesis and pathophysiology of bovine laminitis.

The Making or Faking of Emotionally Significant Brands

The popularity of 'Emotional Branding' and of ESP (Emotional Selling Proposition) was often based on the erroneous assumption that emotions can be simply 'glued' to brands by means of advertising. This assumption originated in the Classical Conditioning theory (you will recall Ivan Pavlov and his experiments with the salivating dogs). Today, this theory is largely obsolete, and thus abandoned as a means for modeling the human attribution of emotional significance. The unfortunate result of branding efforts based on these assumptions was the ineffectiveness of many branding campaigns. In other words, this kind of Emotional Branding is faking rather than making emotionally significant brands. It creates look-alikes. The symbolizations, the advertising, the packaging may evoke emotions and impress the untrained eye, but the brand will lack genuine feel appeal to its target consumers. In the e-booklet downloadable from this site, I set out to present a comprehensive account of why and how brands become (and can be designed to be) desirable even irresistible and achieve emotional significance. This summary outlines the approach in brief but please be aware that most of the theoretical buildup is beyond its scope and that it excludes the many practical guidelines and tips you can find in the e-booklet.

Epilepsy Education Within the Statutory School System

Epilepsy Education Within the Statutory School System