scholarly journals Evaluating spatiotemporal integration of shape cues

2019 ◽  
Author(s):  
Taylor Burchfield ◽  
Ernest Greene

ABSTRACTPrior work has shown that humans can successfully identify letters that are constructed with a sparse array of dots, wherein the dot pattern reflects the strokes that would normally be used to fashion a given letter. In the present work the dots were briefly displayed, one at a time in sequence, varying the spatial order in which they were shown. A forward sequence was spatially ordered as though one were passing a stroke across the dots to connect them. Experiments compared this baseline condition to the following three conditions: a) the dot sequence was spatially ordered, but in the reverse direction from how letter strokes might normally be written; b) the dots in each stroke of the letter were displayed in a random order; c) the sequence of displayed dots were chosen for display from any location in the letter. Significant differences were found between the baseline condition and all three of the comparison conditions, with letter recognition being far worse for the random conditions than for conditions that provided consistent spatial ordering of dot sequences. These findings show that spatial order is critical for integration of shape cues that have been sequentially displayed.

2009 ◽  
Vol 16 (1) ◽  
pp. 190-193 ◽  
Author(s):  
V. DRAGO ◽  
P.S. FOSTER ◽  
D. EDWARD ◽  
B. WARGOVICH ◽  
K.M. HEILMAN

AbstractPatients with corticobasal degeneration (CBG) often demonstrate agraphesthesia in the same hand they demonstrate apraxia. To recognize letters written in their hand subjects can develop a spatial representation and access graphemic representations. Alternatively, people can use movement working memory and match movement patterns to stored letter movement representations. To learn the method normally used without vision, normal subjects (12) had letters written on their palm either in the normal manner or in a reverse direction. If letters written on the hand are recognized by their spatial features (as when visually reading) direction should not influence letter recognition, but if letters written on the hand are recognized by movement patterns, then in the reverse condition recognition should be impaired. When letters were written normally there were no differences in error between the tactile and visual modality. When letters were written in reverse, however, normal subjects made more errors in the tactile than visual condition. Normally, people identify letters written on their hand by covertly copying (mirroring) the examiner and then access letter movement representations. This might explain why patients with CBG often have agraphesthesia associated with apraxia. (JINS, 2010, 16, 190–193.)


2004 ◽  
Vol 13 (2) ◽  
Author(s):  
T Taryono

Spatial order of a region include purpose of structure and interrelatedness of spatial order which as a unity of development mechanism. Spatial order can’t be part from law basic that is UUD’45 and GBHN, in order to the management can be integrated and keep the environment. Spatial order also take note of physical factor and non physical factor. Physical factor consist of soil, water, flora, and fauna. Non physical factors consist of environment, social, economic, and soon. The principle of arrangement of spatial order in a region include national region, regional and local, and a region as an administrative baoundary, that is local government authority, like province, district, subdistrict, and village. The effort for spatial ordering of the environment, for example ordering resource, arrangement of allocation and location, arrangement of environmental aesthetic  and arrangement of environmental quality.


Author(s):  
Z.L. Wang ◽  
J. Bentley ◽  
R.E. Clausing ◽  
L. Heatherly ◽  
L.L. Horton

It has been found that the abrasion of diamond-on-diamond depends on the crystal orientation. For a {100} face, the friction coefficient for sliding along <011> is much higher than that along <001>. For a {111} face, the abrasion along <11> is different from that in the reverse direction <>. To interpret these effects, a microcleavage mechanism was proposed in which the {100} and {111} surfaces were assumed to be composed of square-based pyramids and trigonal protrusions, respectively. Reflection electron microscopy (REM) has been applied to image the microstructures of these diamond surfaces.{111} surfaces of synthetic diamond:The synthetic diamonds used in this study were obtained from the De Beers Company. They are in the as-grown condition with grain sizes of 0.5-1 mm without chemical treatment or mechanical polishing. By selecting a strong reflected beam in the reflection high-energy electron diffraction (RHEED) pattern, the dark-field REM image of the surface is formed (Fig. 1).


1997 ◽  
Vol 44 (10) ◽  
pp. 1853-1862
Author(s):  
A. GORLITZ , T. HANSCH and A. HEMMERIC

VASA ◽  
2005 ◽  
Vol 34 (4) ◽  
pp. 255-261 ◽  
Author(s):  
Diehm ◽  
Baumgartner ◽  
Silvestro ◽  
Herrmann ◽  
Triller ◽  
...  

Background: Open surgical or endovascular abdominal aortic aneurysm (AAA) relies on precise preprocedual imaging. Purpose of this study was to assess inter- and intraobserver variation of software-supported automated and manual multi row detector CT angiography (MDCTA) in aortoiliac diameter measurements before AAA repair. Patients and methods: Thirty original MDCTA data sets (4 times 2mm collimation) of patients scheduled for endovascular AAA repair were studied on a dedicated software capable of creating two-dimensional reformatted planes orthogonal to the aortoiliac center-line. Measurements were performed twice with a four-week interval between readings. Data were analysed by two blinded readers at random order. Two different measurement methods were performed: reader-assisted freehand wall-to-wall measurement and semi-automatic measurement. Results: Aortoiliac diameters were significantly underestimated by the semi-automatic method as compared to reader-assisted measurements (p < 0.0031). Intraobserver variability of AAA diameter calculation was not significant (p > 0.15) for reader-assisted measurements except for the diameter of the left common iliac artery in reader 2 (p = 0.0045) and it was not significant (p > 0.14) using the semi-automatic method. Interobserver variability was not significant for AAA diameter measurements using the reader-assisted method and for proximal neck analysis with the semi-automatic method (p > 0.27). Relevant interobserver variation was observed for semi-automatic measurement of maximum AAA (p = 0.0007) and iliac artery diameters (p = 0.024). Conclusions: Dedicated MDCTA software provides a useful tool to minimize aortoiliac diameter measurement variation and to improve imaging precision before AAA repair. For reliable AAA diameter analysis the reader-assisted freehand measurement method is recommended to be applied to a set of reformatted CT data as provided by the software used in this study.


2021 ◽  
Vol 35 (1) ◽  
pp. 15-22
Author(s):  
Kohei Fuseda ◽  
Jun’ichi Katayama

Abstract. Interest is a positive emotion related to attention. The event-related brain potential (ERP) probe technique is a useful method to evaluate the level of interest in dynamic stimuli. However, even in the irrelevant probe technique, the probe is presented as a physical stimulus and steals the observer’s attentional resources, although no overt response is required. Therefore, the probe might become a problematic distractor, preventing deep immersion of participants. Heartbeat-evoked brain potential (HEP) is a brain activity, time-locked to a cardiac event. No probe is required to obtain HEP data. Thus, we aimed to investigate whether the HEP can be used to evaluate the level of interest. Twenty-four participants (12 males and 12 females) watched attractive and unattractive individuals of the opposite sex in interesting and uninteresting videos (7 min each), respectively. We performed two techniques each for both the interesting and the uninteresting videos: the ERP probe and the HEP techniques. In the former, somatosensory stimuli were presented as task-irrelevant probes while participants watched videos: frequent (80%) and infrequent (20%) stimuli were presented at each wrist in random order. In the latter, participants watched videos without the probe. The P2 amplitude in response to the somatosensory probe was smaller and the positive wave amplitudes of HEP were larger while watching the videos of attractive individuals than while watching the videos of unattractive ones. These results indicate that the HEP technique is a useful method to evaluate the level of interest without an external probe stimulus.


2017 ◽  
Vol 48 (1) ◽  
pp. 40-46 ◽  
Author(s):  
Jolanda Jetten ◽  
Rachel Ryan ◽  
Frank Mols

Abstract. What narrative is deemed most compelling to justify anti-immigrant sentiments when a country’s economy is not a cause for concern? We predicted that flourishing economies constrain the viability of realistic threat arguments. We found support for this prediction in an experiment in which participants were asked to take on the role of speechwriter for a leader with an anti-immigrant message (N = 75). As predicted, a greater percentage of realistic threat arguments and fewer symbolic threat arguments were generated in a condition in which the economy was expected to decline than when it was expected to grow or a baseline condition. Perhaps more interesting, in the economic growth condition, the percentage realistic entitlements and symbolic threat arguments generated were higher than when the economy was declining. We conclude that threat narratives to provide a legitimizing discourse for anti-immigrant sentiments are tailored to the economic context.


2001 ◽  
Author(s):  
Isabel Gauthier ◽  
William G. Hayward ◽  
Chun-Nang Wong
Keyword(s):  

1990 ◽  
Vol 29 (02) ◽  
pp. 51-53
Author(s):  
G. Edlund ◽  
V. Kempi

Patients with the clinical diagnosis of acute cholecystitis were studied with intravenous cholecystography and cholescintigraphy. The two examinations alternated in a random order. The final diagnosis was ascertained by surgery in most patients. Either cholecystography or cholescintigraphy could be used in the diagnostics of patients with suspected acute cholecystitis. The methods have about the same accuracy. However, cholescintigraphy is performed more easily and more rapidly than intravenous cholecystography.


Sign in / Sign up

Export Citation Format

Share Document