Despite an obvious demand for a variety of statistical tests adapted to classification images, few have been proposed. We argue that two based on random field theory (RFT) satisfy this need smooth images. illustrate these images representative the literature from F. Gosselin and P. G. Schyns (2001) A. B. Sekuler, C. M. Gaspar, J. Gold, Bennett (2004). The necessary computations are performed using Stat4Ci Matlab toolbox.

Configural processing in autism was studied Experiment 1 by using the face inversion effect. A normal effect observed participants with autism, suggesting intact configural processing. priming paradigm partial or complete faces served 2 to assess both local and Overall, effects were found irrespective of whether primes intuitive parts (i.e., eyes, nose, etc.) arbitrary segments. An exception, however, that showed magnified single relative typically developing control participants. The...

By using a visual search task, this study examined the encoding of orientation and size for stimuli defined in five different surface media: luminance, color, texture, relative motion, binocular disparity. Results indicated spatially parallel analysis features all media, with possible exception The data also revealed rate asymmetry task Parallel or shallow functions were obtained oblique targets vertical distractors, whereas steeper serial distractors. No consistent was found large small...

The determination of the visual features mediating letter identification has a long-standing history in cognitive science. Researchers have proposed many sets as important for identification, but no such yet been derived directly from empirical data. In study reported here, we applied Bubbles technique to reveal which areas at five different spatial scales are efficient lowercase and uppercase Arial letters. We provide first evidence that line terminations most identification. propose these...

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Abstract A series of experiments was conducted on a patient (ELM) with bilateral inferior temporal lobe damage and category-specific visual agnosia in order to specify the nature his functional impairment. In Experiment 1, ELM performed task picture/word matching that used line drawings fruits vegetables as stimuli. The pattern confusions exhibited by suggested failure processing full range shape features necessary for unique specification target relative other structurally related items....

Abstract Brain-damaged subjects who had previously been identified as suffering from a visual attention deficit for contralesional stimulation were tested on series of search tasks. The experiments examined the hypothesis that processing single features is preattentive but feature integration, necessary correct perception conjunctions features, requires (Treisman & Gelade, 1980 Treisman Sato, 1990). Subjects searched target (orientation or color) conjunction and in unilateral displays which...

We applied the Bubbles technique to reveal directly spatio-temporal features of uppercase Arial letter identification. asked four normal readers each identify 26,000 letters that were randomly sampled in space and time; afterwards, we performed multiple linear regressions on participant's response accuracy space-time samples. contend cluster connected significant regression coefficients is a feature. To bridge gap between identification literature this experiment, also determined relative...

The diagnosis of letter-by-letter (LBL) dyslexia is based on the observation a substantial and monotonic increase word naming latencies as number letters in stimulus increases. This pattern performance typically interpreted indicating that recognition LBL depends sequential identification individual letters. We show, 7 patients, word-length effect can be eliminated if words different lengths are matched sum confusability (visual similarity between letter remainder alphabet) their constituent...

Background Skilled adult readers, in contrast to beginners, show no or little increase reading latencies as a function of the number letters words up seven letters. The information extraction strategy underlying such efficiency word identification is still largely unknown, and methods that allow tracking letter through time between eye saccades are needed fully address this question. Methodology/Principal Findings present study examined use during reading, by means Bubbles technique. Ten...

Abstract It is generally accepted that the left hemisphere (LH) more capable for reading than right (RH). Left hemifield presentations (initially processed by RH) lead to a globally higher error rate, slower word identification, and significantly stronger length effect (i.e., reaction times longer words). Because visuo-perceptual mechanisms of brain recognition are primarily localized in LH (Cohen et al., 2003), it possible this part possesses better spatial frequency (SF) tuning processing...

Abstract Category-specific visual agnosia following bilateral inferior temporal lobe stroke was investigated in the patient ELM. Experiment 1 verified that computer-generated blobs could not be identified when members of a set varied along single but multiple shape dimensions. Experiments 2 through 6 showed for both ELM and, to much lesser degree, healthy participants, this dimensionality effect modulated by semantics. By pairing exact same shapes with semantically close vs. disparate sounds...