We have measured reaction time (RT) to motion onset in two groups of subjects (average ages: 70 and 29 years), for horizontal gratings of 1 c deg-1, modulated in either luminance or colour (equiluminant red-green), for various contrasts and speeds. For both old and young subjects, RTs depended on both speed and contrast, being faster at high speeds and high contrasts, and showed a stronger cont...

The views of people concerning euthanasia are influenced by their fears of enduring intolerable pain, of being trapped by machines beyond their control and of losing bodily integrity and personal dignity in the final stages of their lives. A multitude of achievements in modern medicine and information provided by the mass media serve to reinforce and even provoke a person’s fear of being kept b...

Does human vision show the contrast invariance expected of an ideal stereoscopic system for computing depth from disparity? We used random-dot stereograms to investigate the luminance contrast effect on perceived depth from disparity. The perceived depth of disparity corrugations was measured by adjusting the length of a horizontal line to match the perceived depth of the corrugations at variou...

Moving cars give the illusion of slowing down in foggy conditions, because low contrast reduces perceived speed. A grey square that drifts horizontally across a surround of black and white vertical stripes appears to stop and start as it crosses each stripe, because its contrast keeps changing. A moving square whose vertical and horizontal edges have different contrasts will show illusory disto...

Above threshold, two superimposed sinusoidal gratings of the same spatial frequency (eg 1 cycle deg-1) and equal contrasts, and with orientations balanced around vertical, usually look like a compound structure containing vertical and horizontal edges. However, at large plaid angles (ie large differences between component orientations) and low plaid contrasts there is a tendency for the stimulu...

This study compared the effects of age on the perception of translational, radial, and rotational global motion patterns. Motion coherence thresholds were measured for judging the direction of each motion type as a function of contrast (visibility) and temporal sampling rate in young and elderly participants. Coherence thresholds decreased as dot contrast increased asymptoting at high dot contr...

Cross-orientation suppression was measured in human primary visual cortex (V1) to test the normalization model. Subjects viewed vertical target gratings (of varying contrasts) with or without a superimposed horizontal mask grating (fixed contrast). We used functional magnetic resonance imaging (fMRI) to measure the activity in each of several hypothetical channels (corresponding to subpopulatio...

Forecasts generated with 1 and 4 km grid spacing using the WRF-ARW model (ARW1 and ARW4, respectively) during the 2009-2011 NOAA Hazadous Weather Testbed Spring Experiments by the Center for Analysis and Prediction of Storms are compared and verified using object-based measures, including average values of object attributes, the Object-based Threat Score (OTS) and the Median of Maximum Interest...

Natural convection heat transfer in a square enclosure with a horizontal baffle at the centerline of the left wall containing Al2O3-water in the presence of a magnetic field is investigated numerically. The top and bottom horizontal walls are adiabatic. The left wall and the baffle are maintained in constant temperature Th and the right wall is maintained in...

Abstract The article explores sensations’ role in cognition through analyzing expressions natural language search of a sensory schema. I argue that if it exists, the schema originates from universal need to differentiate between patterns by increasing contrasts, which is linguistically manifested practice grading adjectives and adverbs context antonyms.