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Motor Control Jun 2024Prior work has demonstrated the presence of hysteresis effects in the control of affordance-guided behavior, in that behavioral transitions around a critical action...
Prior work has demonstrated the presence of hysteresis effects in the control of affordance-guided behavior, in that behavioral transitions around a critical action boundary vary with directions of change in said action boundary. To date, research on this topic has overlooked the influence of the global context on these phenomena. We employ an affordance-based reaching task, whereby participants were asked to move a target to a goal by passing through one of two apertures (size variable or size constant). It was found that the direction of change in the size of the variable aperture influenced the point of behavioral transitions, and this effect interacted with the location of a given goal. In addition, we considered fluctuations in the entropy of participants' reach trajectories as a window into the nature of the behavioral phase transitions. Differences in the structure of entropy were found depending on the direction of change in the size variable aperture. These results are discussed in light of a dynamical systems approach, and recommendations for future work are made.
PubMed: 38942417
DOI: 10.1123/mc.2023-0085 -
Journal of Cognitive Neuroscience Jun 2024Our perception of objects depends on non-oculomotor depth cues, such as pictorial distance cues and binocular disparity, and oculomotor depth cues, such as vergence and...
Our perception of objects depends on non-oculomotor depth cues, such as pictorial distance cues and binocular disparity, and oculomotor depth cues, such as vergence and accommodation. Although vergence eye movements are always involved in perceiving real distance, previous studies have mainly focused on the effect of oculomotor state via "proprioception" on distance and size perception. It remains unclear whether the oculomotor command of vergence eye movement would also influence visual processing. To address this question, we placed a light at 28.5 cm and a screen for stimulus presentation at 57 cm from the participants. In the NoDivergence condition, participants were asked to maintain fixation on the light regardless of stimulus presentation throughout the trial. In the WithDivergence condition, participants were instructed to initially maintain fixation on the near light and then turn their two eyes outward to look at the stimulus on the far screen. The stimulus was presented for 100 msec, entirely within the preparation stage of the divergence eye movement. We found that participants perceived the stimulus as larger but were less sensitive to stimulus sizes in the WithDivergence condition than in the NoDivergence condition. The earliest visual evoked component C1 (peak latency 80 msec), which varied with stimulus size in the NoDivergence condition, showed similar amplitudes for larger and smaller stimuli in the WithDivergence condition. These results show that vergence eye movement planning affects the earliest visual processing and size perception, and demonstrate an example of the effect of motor command on sensory processing.
PubMed: 38940732
DOI: 10.1162/jocn_a_02207 -
Annals of Ibadan Postgraduate Medicine Apr 2024Soft tissue masses are commonly encountered in surgical and general medical practice. The graduating medical student should therefore be competent in the physical...
INTRODUCTION
Soft tissue masses are commonly encountered in surgical and general medical practice. The graduating medical student should therefore be competent in the physical examination of a lump. Paucity of real patients makes it paramount that models be used for teaching and evaluation. This study purposed to describe the perception of graduating medical students to the use of a low-cost lump model for Objective Structured Clinical Examination (OSCE).
METHODS
This was a cross-sectional survey of final year medical students who participated in a surgery OSCE utilizing an innovative low-cost lump model.
RESULTS
One hundred and sixty students undertook the OSCE examination while 130 (81.3%) students completed the survey questionnaire. One hundred and forty students (87.5%) passed (score 5) the skills assessment using the lump model. The median age of the students who completed the questionnaire was 25 (range 24-27) years. There were more males N=84 (65.6%) than females N= 44 (34.4%). Two thirds (67.2%; n=84) of the students said the model simulated a true lump. Nearly all the students agreed that the signs of site (97.6%; n=127), size (97.6%; n=127), shape (95.4%; n=124) and transillumination (95.4%; n=124) were clearly demonstrable with the model. A lower proportion of agreements were seen with signs such as tenderness (64.6%; n=82), attachment (77.7%; n=80) and warmth (58.6%; n=75) while more students disagreed with pulsatility (51.5%; n=67).
CONCLUSION
The medical students had a positive perception to the use of the model. However, further refinements would be needed for more signs to be demonstrable.
PubMed: 38939885
DOI: No ID Found -
Pharmaceuticals (Basel, Switzerland) May 2024Public perception contrasts scientific findings on the depression-related effects of cannabis. However, earlier studies were performed when cannabis was predominantly... (Review)
Review
Public perception contrasts scientific findings on the depression-related effects of cannabis. However, earlier studies were performed when cannabis was predominantly illegal, its production was mostly uncontrolled, and the idea of medical cannabis was incipient only. We hypothesized that recent changes in attitudes and legislations may have favorably affected research. In addition, publication bias against cannabis may have also decreased. To investigate this hypothesis, we conducted a review of research studies published over the last three years. We found 156 relevant research articles. In most cross-sectional studies, depression was higher in those who consumed cannabis than in those who did not. An increase in cannabis consumption was typically followed by an increase in depression, whereas withdrawal from cannabis ameliorated depression in most cases. Although medical cannabis reduced depression in most studies, none of these were placebo-controlled. In clinical studies published in the same period, the placebo also ameliorated depression and, in addition, the average effect size of the placebo was larger than the average effect size of medical cannabis. We also investigated the plausibility of the antidepressant effects of cannabis by reviewing molecular and pharmacological studies. Taken together, the reviewed findings do not support the antidepressant effects of herbal cannabis.
PubMed: 38931356
DOI: 10.3390/ph17060689 -
Molecules (Basel, Switzerland) Jun 2024This research aimed to encapsulate the fruit extract to increase its stability for incorporation into food products such as jelly or jelly powder. After extraction, the...
This research aimed to encapsulate the fruit extract to increase its stability for incorporation into food products such as jelly or jelly powder. After extraction, the nanoliposomes containing the extract were prepared in ratios of 60-0, 50-10, 40-20, and 30-30 lecithin-to-cholesterol. The effects of lecithin-to-cholesterol concentrations on the related parameters were then evaluated. The results showed that the average particle size was in the range of 95.05 to 164.25 nm, and with an increasing cholesterol concentration, the particle size of the nanoliposomes increased. The addition of cholesterol increased the zeta potential from -60.40 to -68.55 millivolt. Furthermore, cholesterol led to an increase in encapsulation efficiency, and even improved the stability of phenolic compounds loaded in nanoliposomes during storage time. Fourier transform infrared (FTIR) spectroscopy confirmed the successful loading of the extract. Field emission scanning electron microscopy (FE-SEM) analysis revealed nano-sized spherical and almost-elliptical liposomes. For jelly powders, the water solubility index ranged from 39.5 to 43.7% ( > 0.05), and the hygroscopicity values ranged between 1.22 and 9.36 g/100 g ( < 0.05). In conclusion, nanoencapsulated extract displayed improved stability and can be used in jelly preparation without any challenge or unfavorable perception.
Topics: Liposomes; Plant Extracts; Capparis; Particle Size; Nanoparticles; Lecithins; Cholesterol; Drug Compounding; Spectroscopy, Fourier Transform Infrared; Solubility
PubMed: 38930869
DOI: 10.3390/molecules29122804 -
Foods (Basel, Switzerland) Jun 2024Despite its importance as an undesirable food texture, the phenomenon of chalkiness remains understudied. sensations presumably arise from fine particulates found in...
Despite its importance as an undesirable food texture, the phenomenon of chalkiness remains understudied. sensations presumably arise from fine particulates found in foods, but semantic overlap with other common descriptors of small particles, like gritty or sandy, is unclear. Here, we compare the usage of with related descriptors, and determine the effect of particle size, concentration, and xanthan content on ratings in a model beverage. A 2 factorial design with starch particle size (D = 33.8 and 64.6 µm), starch concentrations (10 and 20% /), and xanthan content (0.075 and 0.15% /) was used. Participants' salivary flow rate was also assessed. A multi-sip taste test was performed where naïve consumers (n = 82; 39% men, 60% women; age range = 18-79 years) rated the intensity of , , , , , and at 0, 30, and 60 s after each of three consecutive sips. All attribute ratings were highly correlated, with , , and being more closely correlated with each other than or . Although was still reported 60 s after consumption, no evidence of build-up was found with repeated sips. A larger size and higher concentration increased ratings, with the low-salivary-flow group reporting greater ratings for relative to the high-flow group. Our results suggest consumer percepts of small particles are overlapping but not entirely redundant. This suggests researchers and product developers should carefully distinguish between these descriptors when trying to understand consumer perception of food products containing fine particles.
PubMed: 38928793
DOI: 10.3390/foods13121852 -
Cognitive Science Jun 2024Experiments on visually grounded, definite reference production often manipulate simple visual scenes in the form of grids filled with objects, for example, to test how...
Experiments on visually grounded, definite reference production often manipulate simple visual scenes in the form of grids filled with objects, for example, to test how speakers are affected by the number of objects that are visible. Regarding the latter, it was found that speech onset times increase along with domain size, at least when speakers refer to nonsalient target objects that do not pop out of the visual domain. This finding suggests that even in the case of many distractors, speakers perform object-by-object scans of the visual scene. The current study investigates whether this systematic processing strategy can be explained by the simplified nature of the scenes that were used, and if different strategies can be identified for photo-realistic visual scenes. In doing so, we conducted a preregistered experiment that manipulated domain size and saturation; replicated the measures of speech onset times; and recorded eye movements to measure speakers' viewing strategies more directly. Using controlled photo-realistic scenes, we find (1) that speech onset times increase linearly as more distractors are present; (2) that larger domains elicit relatively fewer fixation switches back and forth between the target and its distractors, mainly before speech onset; and (3) that speakers fixate the target relatively less often in larger domains, mainly after speech onset. We conclude that careful object-by-object scans remain the dominant strategy in our photo-realistic scenes, to a limited extent combined with low-level saliency mechanisms. A relevant direction for future research would be to employ less controlled photo-realistic stimuli that do allow for interpretation based on context.
Topics: Humans; Speech; Male; Female; Eye Movements; Adult; Young Adult; Visual Perception; Attention; Photic Stimulation
PubMed: 38924126
DOI: 10.1111/cogs.13473 -
Revista Gaucha de Enfermagem 2024To analyze the effectiveness of Bach flower therapy compared to placebo in reducing perceived stress levels in primary health care nursing professionals. (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To analyze the effectiveness of Bach flower therapy compared to placebo in reducing perceived stress levels in primary health care nursing professionals.
METHOD
Pragmatic, parallel randomized clinical trial conducted with 87 primary care nursing professionals with self-identified stress, from October 2021 to June 2022, in the cities of Osasco and São Paulo, Brazil. The intervention group (n=43) received the collective flower formula, and the placebo group (n=44) received only the diluent. Data analysis was performed using the linear mixed model, and effect size was measured by partial Eta squared, significance level 5%.
RESULTS
Data analysis showed a significant reduction in perceived stress levels within groups (p=0.038). However, there was no significant difference between the study groups (p=0.750). Participants in the intervention group reported a greater perception of changes than participants in the placebo group, but without statistical significance (p=0,089).
CONCLUSION
The floral formula was not more effective than the placebo formula in reducing perceived stress. There was a significant stress reduction among nursing professionals in both study groups, although with a small effect size.
Topics: Humans; Female; Male; Adult; Flowers; Primary Care Nursing; Middle Aged; Occupational Stress; Phytotherapy; Stress, Psychological; Brazil
PubMed: 38922232
DOI: 10.1590/1983-1447.2024.20230132.en -
Behavioral Sciences (Basel, Switzerland) Jun 2024The pervasive integration of digital platforms into daily life has amplified their perceived indispensability. This study investigates the factors influencing this...
The pervasive integration of digital platforms into daily life has amplified their perceived indispensability. This study investigates the factors influencing this perception across countries with contrasting platform landscapes, focusing on platform quality and usage patterns. We conducted surveys in Finland and Korea, countries representing distinct platform ecosystems. The results revealed higher perceived indispensability in Korea than in Finland, with usefulness and habitual platform use emerging as significant predictors of indispensability in both countries. However, the specific aspects of platform quality influencing this perception diverged. In Finland, the platform's comprehensiveness and security risk significantly impacted indispensability, while social interaction features played a negligible role. Conversely, in Korea, social interaction features significantly influenced indispensability, while platform comprehensiveness and security risk were non-significant. These findings underscore the multifaceted nature of digital platform indispensability, shaped by the interaction of platform quality and usage patterns. The contextual variations highlighted by our cross-country comparison suggest that a one-size-fits-all approach to platform regulation or user education may be ineffective. Future research should explore these cultural and platform-specific nuances to devise tailored policies.
PubMed: 38920834
DOI: 10.3390/bs14060502 -
Scientific Reports Jun 2024As the global population ages, understanding of the effect of aging on visual perception is of growing importance. This study investigates age-related changes in...
As the global population ages, understanding of the effect of aging on visual perception is of growing importance. This study investigates age-related changes in adulthood along size perception through the lens of three visual illusions: the Ponzo, Ebbinghaus, and Height-width illusions. Utilizing the Bayesian conceptualization of the aging brain, which posits increased reliance on prior knowledge with age, we explored potential differences in the susceptibility to visual illusions across different age groups in adults (ages 20-85 years). To this end, we used the BTPI (Ben-Gurion University Test for Perceptual Illusions), an online validated battery of visual illusions developed in our lab. The findings revealed distinct patterns of age-related changes for each of the illusions, challenging the idea of a generalized increase in reliance on prior knowledge with age. Specifically, we observed a systematic reduction in susceptibility to the Ebbinghaus illusion with age, while susceptibility to the Height-width illusion increased with age. As for the Ponzo illusion, there were no significant changes with age. These results underscore the complexity of age-related changes in visual perception and converge with previous findings to support the idea that different visual illusions of size are mediated by distinct perceptual mechanisms.
Topics: Humans; Aged; Adult; Middle Aged; Aged, 80 and over; Female; Male; Aging; Young Adult; Size Perception; Visual Perception; Illusions; Bayes Theorem
PubMed: 38918501
DOI: 10.1038/s41598-024-65405-6