Capturing Attention to Brake Lamps in a Single Fixation

Object The use of dural grafts is frequently unavoidable when tension-free dural closure cannot be achieved following neurosurgical procedures or trauma. Biodegradable collagen matrices serve as a scaffold for the regrowth of natural tissue and require no suturing. The aim of this study was to investigate the efficacy and safety of dural repair with a collagen matrix using different fixation techniques. Methods A total of 221 patients (98 male and 123 female; mean age 55.6 ± 17.8 years) undergoing cranial (86.4%) or spinal (13.6%) procedures with the use of a collagen matrix dural graft were included in this retrospective study. The indications for use, fixation techniques, and associated complications were recorded. Results There were no complications of the dural graft in spinal use. Five (2.6%) of 191 patients undergoing cranial procedures developed infections, 3 of which (1.6%) were deep infections requiring surgical revision. There was no statistically significant relationship between the operative field status before surgery and the occurrence of a postoperative wound infection (p = 0.684). In the 191 patients undergoing a cranial procedure, cerebrospinal fluid (CSF) collection occurred in 5 patients (2.6%) and a CSF fistula in 5 (2.6%), 3 of whom (1.6%) required surgical revision. No patient who underwent an operation with preexisting CSF leakage had postoperative CSF leakage. Postoperative infection significantly increased the risk for postoperative CSF leakage. The collagen matrix was used without additional fixation in 124 patients (56.1%), with single fixation in 55 (24.9%), and with multiple fixations in 42 (19%). There were no systemic allergic reactions or local skin changes. Follow-up imaging in 112 patients (50.7%) revealed no evidence of any adverse reaction to the collagen graft. Conclusions The collagen matrix is an effective and safe cranial and spinal dural substitute that can be used even in cases of an existing local infection. Postoperative deep infection increases the risk for CSF leakage.

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Eye movement control in Turkish sentence reading

Quarterly Journal of Experimental Psychology ◽

10.1177/1747021820963310 ◽

2020 ◽

pp. 174702182096331

Author(s):

Ayşegül Özkan ◽

Figen Beken Fikri ◽

Bilal Kırkıcı ◽

Reinhold Kliegl ◽

Cengiz Acartürk

Keyword(s):

Wide Spectrum ◽

Distributed Processing ◽

Movement Control ◽

Predictive Processing ◽

Base Line ◽

Discourse Comprehension ◽

Morphological Effect ◽

Fixation Durations ◽

Single Fixation ◽

High Level

Reading requires the assembly of cognitive processes across a wide spectrum from low-level visual perception to high-level discourse comprehension. One approach of unravelling the dynamics associated with these processes is to determine how eye movements are influenced by the characteristics of the text, in particular which features of the words within the perceptual span maximise the information intake due to foveal, spillover, parafoveal, and predictive processing. One way to test the generalisability of current proposals of such distributed processing is to examine them across different languages. For Turkish, an agglutinative language with a shallow orthography–phonology mapping, we replicate the well-known canonical main effects of frequency and predictability of the fixated word as well as effects of incoming saccade amplitude and fixation location within the word on single-fixation durations with data from 35 adults reading 120 nine-word sentences. Evidence for previously reported effects of the characteristics of neighbouring words and interactions was mixed. There was no evidence for the expected Turkish-specific morphological effect of the number of inflectional suffixes on single-fixation durations. To control for word-selection bias associated with single-fixation durations, we also tested effects on word skipping, single-fixation, and multiple-fixation cases with a base-line category logit model, assuming an increase of difficulty for an increase in the number of fixations. With this model, significant effects of word characteristics and number of inflectional suffixes of foveal word on probabilities of the number of fixations were observed, while the effects of the characteristics of neighbouring words and interactions were mixed.

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Visual Cortex Neurons of Monkeys and Cats: Temporal Dynamics of the Spatial Frequency Response Function

Journal of Neurophysiology ◽

10.1152/jn.00858.2003 ◽

2004 ◽

Vol 91 (6) ◽

pp. 2607-2627 ◽

Cited By ~ 45

Author(s):

Robert A. Frazor ◽

Duane G. Albrecht ◽

Wilson S. Geisler ◽

Alison M. Crane

Keyword(s):

Spatial Frequency ◽

Striate Cortex ◽

Temporal Dynamics ◽

Temporal Integration ◽

Direction Selectivity ◽

Response Latencies ◽

Low Frequencies ◽

Transient Nature ◽

Integration Strategies ◽

Single Fixation

We measured the responses of striate cortex neurons as a function of spatial frequency on a fine time scale, over the course of an interval that is comparable to the duration of a single fixation (200 ms). Stationary gratings were flashed on for 200 ms and then off for 300 ms; the responses were analyzed at sequential 1-ms intervals. We found that 1) the preferred spatial frequency shifts through time from low frequencies to high frequencies, 2) the latency of the response increases as a function of spatial frequency, and 3) the poststimulus time histograms (PSTHs) are relatively shape-invariant across spatial frequency. The dynamic shifts in preferred spatial frequency appear to be a simple consequence of the latency shifts and the transient nature of the PSTH. The effects of these dynamic shifts on the coding of spatial frequency information are examined within the context of several different temporal integration strategies, and pattern-detection performance is determined as a function of the interval of integration, following response onset. The findings are considered within the context of related investigations as well as a number of functional issues: motion selectivity in depth, “coarse-to-fine” processing, direction selectivity, latency as a code for stimulus attributes, and behavioral response latency. Finally, we demonstrate that the results are qualitatively consistent with a simple feedforward model, similar to the one originally proposed in 1962 by Hubel and Wiesel, that incorporates measured differences in the response latencies and the receptive field sizes of different lateral geniculate nucleus inputs.

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Single-stage clipping with bifrontal and bilateral frontotemporal craniotomies for subarachnoid hemorrhage with multiple cerebral aneurysms using Sugita head holding system: A case report

Surgical Neurology International ◽

10.25259/sni_73_2020 ◽

2020 ◽

Vol 11 ◽

pp. 76

Author(s):

Masahito Katsuki ◽

Naomichi Wada ◽

Yasunaga Yamamoto

Keyword(s):

Subarachnoid Hemorrhage ◽

Cerebral Artery ◽

Treatment Strategies ◽

Cerebral Aneurysms ◽

Single Stage ◽

Ruptured Aneurysm ◽

Left Middle Cerebral Artery ◽

Multiple Aneurysms ◽

Single Fixation ◽

The Right

Background: Subarachnoid hemorrhage with multiple aneurysms is very challenging because it is difficult to identify the ruptured aneurysm. We could not identify the ruptured aneurysm preoperatively, so we decided to treat all of the aneurysms as a single-stage surgery. Case Description: A 79-year-old woman was diagnosed with subarachnoid hemorrhage with multiple cerebral aneurysms at the right distal anterior cerebral artery, left middle cerebral artery, and right internal carotid artery- posterior communicating artery bifurcation. We could not identify the ruptured aneurysm preoperatively. We fixed her head using the Sugita head holding system (Mizuho Co., Ltd., Tokyo) and performed clipping for each aneurysm with bifrontal craniotomy and bilateral frontotemporal craniotomy as a single-stage operation. The last aneurysm seemed ruptured, and clipping for all the aneurysms was successful. She was discharged with a good postoperative course. The Sugita head holding system allowed turning the head of the patient toward the right and left with single fixation, leading to this single-stage operation. Conclusion: Several methods for identifying a ruptured aneurysm from multiple aneurysms have been reported, but under limited medical resources, this procedure would be one of the treatment strategies.

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Parafoveal Words are Effective in Both Hemifields: Preattentive Processing of Semantic and Phonological Codes

Perception ◽

10.1068/p120213 ◽

1983 ◽

Vol 12 (2) ◽

pp. 213-221 ◽

Cited By ~ 42

Author(s):

Geoffrey Underwood ◽

Jennifer Rusted ◽

Sandra Thwaites

Keyword(s):

Lexical Decision ◽

Response Latency ◽

Visual Angle ◽

Automatic Processing ◽

Horizontal Axis ◽

Semantic Relationship ◽

Preattentive Processing ◽

Visual Hemifield ◽

Single Fixation ◽

Phonological Activation

What effect may an unattended word have during a single fixation? Attention was selectively directed to a word exposed for 50 ms by the demand to make a rapid lexical decision response, and during the same presentation a second word was displayed approximately 2.3 deg of visual angle away on the same horizontal axis. The second word was backwards and forwards masked by a random-dot display, and was described to subjects as a distractor which was to be ignored. Although no response was required to this word, it was found to influence response latency to the attended word according to the semantic relationship which existed between the two. They interfered with the lexical decision response when the two words were related in meaning and also when they sounded as if they were related in meaning. These effects argue for automatic processing of the meaning of printed words presented in either visual hemifield, and for their automatic phonological activation.

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How radiographers visually perceive X-ray images with the task of accepting or rejecting them – a pilot study

Radiography Open ◽

10.7577/radopen.1997 ◽

2017 ◽

Vol 3 (1) ◽

pp. 10

Author(s):

Dag Waaler ◽

Sigrid Hammer ◽

Camilla Langdalen ◽

Linn Therese Håkonsen Haug

Keyword(s):

Eye Tracking ◽

Work Experience ◽

Quality Evaluation ◽

Large Individual ◽

X Ray ◽

Monitor Display ◽

Fixation Durations ◽

Projection Images ◽

Single Fixation ◽

Gaze Fixations

Introduction: Radiographer´s usual role in the medical imaging chain is to acquire relevant and qualitatively good images that help the radiologist or physician to diagnose most accurately. After the image acquisition, the radiographer does a quality evaluation based on established imaging criteria to decide if the image is satisfactory, or otherwise reject it and subsequently take a new one. Contrary to expectations that the number of image rejects should decrease substantially with the introduction of digital imaging, a number of studies have shown that it has not, although the reasons for rejects has changed from exposure errors to positioning and centring errors. Very little research has been on examining how radiographers visually perceive and evaluate the X-ray images in this acceptance/rejection process.Purpose: Investigate how radiographers and radiography students visually perceives X-ray images in the process of accepting or rejecting them on basis of radiographic imaging criteria, and see if there are differences in strategies across experience levels.Materials and methods: Three radiography students and five radiographers with varying years of experience were given the task of accepting or rejecting shoulder and knee projection images based on positioning criteria. Using eye tracking, we measured the participants’ number and duration of gaze fixations within 1) the field of view defined by the monitor display, 2) the part of the monitor displaying the X-ray image only, and 3) the region within the X-ray images considered to be most relevant given the imaging criteria task. The quantitative eye-tracking measurements were followed-up by four qualitative questions.Results: Some differences in fixation patterns between the groups were found; the medium experienced radiographers spent statistically significant lesser number of fixations and lesser average single fixation durations than both the radiography students and the most experienced radiographers did, whereas the two latter groups scored almost equally. Conclusion: The study revealed that work experience might have some influence on how radiographers and radiography students assess X-ray images, but in subtler ways than expected. The study also revealed, however, quite large individual differences across experience.

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The Magic Number 4 ± 0: A New Look at Visual Numerosity Judgements

Perception ◽

10.1068/p050327 ◽

1976 ◽

Vol 5 (3) ◽

pp. 327-334 ◽

Cited By ~ 131

Author(s):

Janette Atkinson ◽

Fergus W Campbell ◽

Marcus R Francis

Keyword(s):

Spatial Frequency ◽

Response Time ◽

Response Times ◽

Magic Number ◽

Linear Arrays ◽

Spatial Frequencies ◽

Memory Buffer ◽

Single Fixation ◽

New Look

Visual numerosity judgements were made for tachistoscopically presented linear arrays of dots or lines. The interelement interval (which could be specified in spatial frequency terms) was constant for a given array but varied across conditions. A clear limit in the accuracy of numerosity judgements was found to be set at 4 for regularly spaced elements with spatial frequencies below approximately 10 cycles/deg (element and interelement interval of 0·05 deg). This limit in terms of accuracy is accompanied by a fast and almost constant response time for arrays of 4 or less, compared to response times for arrays of more than 4 elements. The limit in accuracy falls to 2 elements rather than 4 for spacing narrower than 0·05 deg although with such spacing the elements are still easily resolved. The limit of 4 is found if the stimulus is a bright afterimage, lasting for approximately 60 s. This result suggests that the limit is independent of the time allowed for a single fixation and is a perceptual limit rather than a limit in some memory buffer. ‘Numerosity’ units are proposed to account for the results.

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