Processing visual ambiguity in fractal patterns: Pareidolia as a sign of creativity

Creativity is a complex, multifaceted and highly valued quality. Characterizing creativity experimentally is a challenging endeavor. While most studies to date have focused on divergent thinking, emerging work also points to an intricate link between creativity and perceptual abilities. Here, we hypothesized that differences in high- and low-creative individuals are already present at the level of sensory perception, specifically in the ability to perceive recognizable forms in noisy or ambiguous stimuli, a phenomenon called pareidolia. To test this, we designed a visual perception task in which 50 participants, with various levels of creativity, were presented with ambiguous stimuli and asked to identify as many recognizable forms as possible. A key manipulation consisted in generating cloud-like images where we manipulated the level of complexity by manipulating fractal dimension (FD) and contrast level. We found that pareidolic perceptions arise more often and more rapidly in creative individuals. Interestingly, less creative individuals have a narrower range of FD values that support the emergence of pareidolia. Our results show that FD and contrast are key visual properties to manipulate when investigating pareidolic perception and its putative link to creativity. They also suggest that pareidolia may be used as a perceptual proxy of idea generation abilities, a prerequisite for creative behavior. In sum, we extend the established body of work on divergent thinking, by introducing divergent perception as a complementary manifestation of the creative mind. Therefore, these findings expand our understanding of the perception-creation link and open new paths in studying creative behavior in humans.

Scientific Production of Researchers Recipiente of CNPq Productivity Grants in the Field of Production Engineering in the 2013-2016 period

This work has the purpose of mapping the scientific production of researchers recipient of CNPq productivity grants in research (PQ) and productivity grants in technological development and innovative extension (DT), in the Production Engineering field, in the four-year period from 2013 to 2016. The information was extracted from the Lattes Platform, on which we obtained quantitative data about the individual scientific production of 190 researchers, through the software scripLattes v8.10. The data analysis was conducted through descriptive statistics, the Kolgomorov-Smirnov data normality test, the Kruskal-Wallis test, and the Mann-Whitney test. The results show that 76% of the researchers compose the PQ grant category. Within the four-year period, among PQ researchers, 1B and 1A researchers had the best average of total published articles, with 19.42 and 15.75 articles per researcher, respectively. Among DT researchers, 1D and level 2 researchers had, in average, 21.5 and 12.57 published articles, respectively. PQ researchers maintain their production of scientific articles homogeneous at all Qualis levels. On the other hand, DT researchers present greater heterogeneity in their publications. It is possible to conclude that level 1 researchers do not focus on journals that present low Qualis ratings for the publication of their research. In contrast, level 2 researchers are less experienced and expect to publish in higher-level journals, but when their works are rejected, they start “betting” on journals of lesser quality.

Visibility of an in-ground signal when texting while walking

An increase in pedestrian accidents associated with smartphone use has been one of the main issues in road traffic safety research and administration. Recently, traffic lights and safety signs embedded in the ground have been introduced, but without sufficient scientific consideration. A laboratory experiment evaluated the visibility of an in-ground signal while varying its contrast and position. Twenty-three participants performed a signal detection task when conducting texting while walking on a treadmill. The signals were displayed randomly onto the ground one at a time at three different positions with three different contrasts levels and moved towards a participant. In results, the approaching signals were detected 1.7 m ~ 2.9 m in front of participants, and there were significant differences in the visibility between contrast levels and positions (p<.01). The findings suggest the importance of proper contrast level and placement when installing in- ground signals for improving their visibility by smartphone users.

Low-contrast Pattern-reversal Visual Evoked Potential in Different Spatial Frequencies

Purpose: To evaluate the pattern-reversal visual evoked potential (PRVEP) in lowcontrast, spatial frequencies in time, frequency, and time-frequency domains. Methods: PRVEP was performed in 31 normal eyes, according to the International Society of Electrophysiology of Vision (ISCEV) protocol. Test stimuli had checkerboard of 5% contrast with spatial frequencies of 1, 2, and 4 cycles per degree (cpd). For each VEP waveform, the time domain (TD) analysis, Fast Fourier Transform(FFT), and discrete wavelet transform (DWT) were performed using MATLAB software. The VEP component changes as a function of spatial frequency (SF) were compared among time, frequency, and time–frequency dimensions. Results: As a consequence of increased SF, a significant attenuation of the P100 amplitude and prolongation of P100 latency were seen, while there was no significant difference in frequency components. In the wavelet domain, an increase in SF at a contrast level of 5% enhanced DWT coefficients. However, this increase had no meaningful effect on the 7P descriptor. Conclusion: At a low contrast level of 5%, SF-dependent changes in PRVEP parameters can be better identified with the TD and DWT approaches compared to the Fourier approach. However, specific visual processing may be seen with the wavelet transform.

Crop Analysis Using Image Processing

To detect the uniqueness and quantities of agriculture product images a new method is proposed using MATLAB software .In this paper we propose a method to increase the contrast level of a image with exponential low pass filter and histogram equalization technique. Next by using region props function we extract the binary features of the image, and then we calculated the number of targets in gray level image. This method can be easily applied in modern agriculture.

A power law study of the edge influence on the perceived filling-in brightness magnitude

Background Edge plays a special role in spatial perception and as well as in determining the brightness of a surface within borders. The aim of our study was to measure threshold brightness in different levels of edges thickness. Methods Steven’s power law for circles modulating in luminance was estimated for 30 subjects (mean age 24 years, SD 3.3, 13 female). Stimuli were presented on the iMac display using the 11-bit graphic board and consisted of two circles of 3° of visual angle, separated by 10°. We tested 7 levels of Michelson contrast: 7, 8, 10, 15, 26, 50, and 100. Three edges filtering were tested (0.3, 0.8, and 1.5° of smoothing). The subjects’ task was to judge the brightness of the edge filtered circle compared with the circle of the hard edge which was considered the modulus and received an arbitrary level of 50, representing the amount of brightness perception. In each trial, the same contrast level was presented in both circles. Five judgments were performed for each contrast level in edge filtering. Results We found an increase in the power law exponent as the increase of the edge filtering (for sigma of 0.3 = 0.43, sigma of 0.8 = 0.73, and sigma 1.5 = 0.97). All power function fitting had high correlation coefficients (r2 = .94, r2 = .95, r2 = .97, respectively to sigma 0.3, 0.8, and 1.5) passing to the model’s adhesion criteria. Conclusions There was a progressive distortion on the figure brightness perception as increasing the edge filtering suggesting the control of edges on the polarity of the overall brightness. Also, perceived brightness was increasingly veridical with increased filtering, approaching 1:1 correspondence at 1.5 sigmas.

‘IVC contrast level: a sign of cardiovascular dysfunction’

Contrast blood level in intrahepatic inferior vena cava (IVC) on arterial contrast-enhanced CT images is referred to as IVC layering or IVC contrast level sign. This sign is important to recognize as it has dismal prognosis and requires immediate attention. The causes described in literature include cardiogenic shock, cardiac arrest and cardiac tamponade. We hereby present three cases depicting IVC contrast level sign.