Development of visual noise mask for human point-light displays

Since the 1970’s Point-Light Display (PLD) stimuli have been widely used in investigations regarding how humans process and recognize human movement. Because humans have a great ability to recognize human motion even in the absence of pictorial information, several studies introduce visual noise in order to make stimuli recognition more challenging. The usual approach is to introduce extra moving dots of similar size that move along to the actual human PLD. To construct such a noise mask, often researchers must develop algorithms that generate random moving dots. Although some authors made platforms allowing manipulations within the algorithmic possibilities available, most of the developed and available ways of visual dot noise masks production rely on paid softwares, have file format restrictions and require the researcher to have extensive programming skills. In this regard, we herein propose to build the noise mask on Blender, a free open source software, with a graphical interface that reads and exports many file formats and enables the manipulation of videos both in 2D and 3D. Therefore, we present a user- friendly step-by-step guide on how to develop visual noise for masking PLD. Specifically, we explain how to set a dynamic movement in a 2D environment that relies mainly on changing an object position on the ‘x' and ‘y' axis. Additionally, we also present how to build the dots and how they can be manipulated to create the desired movement. The herein presented guideline can also be easily translated and applied in the 3D option. Furthermore, we made available the environment of the software with some directions and the set of noise videos developed by our group. Finally, as normally the combination of videos with the mask is crucial, the process of combination of the videos and the mask in Blender is also explained. In sum, the main advantages of the presented methodology are the non-expensiveness and no need of programming experience; thus having no prerequisites to be applied. In particular, this step-by-step guide might be appealing to students engaged in this research topic but who are still novice in programming skills usually required to build visual dot noise masks

The impact of COVID-19 hygienic measures on food choice and eating behaviour

The COVID-19 pandemic has led to several changes that have affected not only emotional and psychological well-being but also eating behavior. Herein, we sought to evaluate if depicting pandemic-related sanitary measures in a food consumption video would impact food appraisal, decreasing food attractiveness and the desire to eat. Participants performed, on two different days, an online protocol in which foods presented in a video, and following, in pictures, were evaluated regarding visual aspect, expected smell and taste, and desire to eat. The videos presented each day differed only regarding the presence/absence of sanitary elements adopted during the pandemic, composing COVID/non-COVID conditions. For both conditions, sweet and high-calorie foods were better evaluated when compared to salty and low-calorie foods, with the sweet food evaluation higher for the non-COVID condition when compared to the COVID-condition. Only for the non-COVID condition was the reported desire to eat higher immediately after the video, and for both conditions, it was higher at the end of the task when compared to the baseline. Correlation analysis suggests that depression and anxiety symptoms may reduce the smell appreciation of foods presented in the pandemic scenario. We conclude that food perception is affected by the presence of the sanitary measures adopted during the pandemic by reducing the desire to eat and food hedonic appreciation and, further, that depression and anxiety symptoms may be related to a higher negative impact of the pandemic on eating behavior.O.M.L. is supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Science, Technology and Higher Education, through the national funds, within the scope of the Transitory Disposition of the Decree No. 57/2016, of 29th of August, amended by Law No. 57/2017 of 19 July (Ref.: SFRH/BPD/72710/2010). This study was conducted at the Psychology Research Centre (PSI/01662), School of Psychology, University of Minho, supported by the Foundation for Science and Technology (FCT) through the Portuguese State Budget (Ref.: UIDB/PSI/01662/2020)

The impact of COVID-19 hygienic measures on food choice and eating behaviour

[Excerpt] The COVID-19 pandemic has led to several changes that have affected not only emotional and psychological well-being but also eating behavior. Herein, we sought to evaluate if depicting pandemic-related sanitary measures in a food consumption video would impact food appraisal, decreasing food attractiveness and the desire to eat. Participants performed, on two different days, an online protocol in which foods presented in a video, and following, in pictures, were evaluated regarding visual aspect, expected smell and taste, and desire to eat. The videos presented each day differed only regarding the presence/absence of sanitary elements adopted during the pandemic, composing COVID/non-COVID conditions. [...

Impacts of COVID-19 sanitary cues on hedonic appreciation of foods

The COVID-19 pandemic led to several lifestyle changes, including eating behavior. Herein, we aimed to evaluate how pandemic-related sanitary cues presented in food videos impact food appraisal and desire to eat, and their priming after-effects on subsequent food pictures presented without such cues. In two online sessions, separated by 4 to 7 days, participants watched either a Non-Pandemic or a Pandemic video of a woman eating, the latter containing sanitary elements adopted during the pandemic. The order of the videos was counterbalanced across participants over the two experimental sessions. Videos were followed by images of food from different categories. After observing both videos and each picture, participants were instructed to evaluate the visual aspect, expected smell and flavor, and rate their desire to eat. Our study demonstrated (1) higher hedonic responses to the Non-Pandemic compared to the Pandemic video, (2) a priming effect showing higher appreciation for sweet foods after the Non-Pandemic compared to the Pandemic video, (3) that food exposure gradually increases one’s desire to eat, but such effects are impacted by pandemic sanitary cues, and (4) greater hedonic responses are given for sweet and high-calorie foods compared to salty and low-calorie ones, irrespective of pandemic priming. Finally, depression and anxiety symptoms were associated with lower smell evaluations only in the Pandemic condition.O.M.L. is supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Science, Technology and Higher Education, through the national funds, within the scope of the Transitory Disposition of the Decree No. 57/2016, of 29 August, amended by Law No. 57/2017 of 19 July (Ref.: SFRH/BPD/72710/2010). This study was conducted at the Psychology Research Centre (PSI/01662), School of Psychology, University of Minho, supported by the Foundation for Science and Technology through the Portuguese State Budget (Ref.: UIDB/PSI/01662/2020)

Lateralised dynamic modulations of corticomuscular coherence associated with bimanual learning of rhythmic patterns

Supplementary Information: The online version contains supplementary material available at https://doi.org/ 10.1038/s41598-022-10342-5Human movements are spontaneously attracted to auditory rhythms, triggering an automatic activation of the motor system, a central phenomenon to music perception and production. Cortico- muscular coherence (CMC) in the theta, alpha, beta and gamma frequencies has been used as an index of the synchronisation between cortical motor regions and the muscles. Here we investigated how learning to produce a bimanual rhythmic pattern composed of low- and high-pitch sounds affects CMC in the beta frequency band. Electroencephalography (EEG) and electromyography (EMG) from the left and right First Dorsal Interosseus and Flexor Digitorum Superficialis muscles were concurrently recorded during constant pressure on a force sensor held between the thumb and index finger while listening to the rhythmic pattern before and after a bimanual training session. During the training, participants learnt to produce the rhythmic pattern guided by visual cues by pressing the force sensors with their left or right hand to produce the low- and high-pitch sounds, respectively. Results revealed no changes after training in overall beta CMC or beta oscillation amplitude, nor in the correlation between the left and right sides for EEG and EMG separately. However, correlation analyses indicated that left- and right-hand beta EEG–EMG coherence were positively correlated over time before training but became uncorrelated after training. This suggests that learning to bimanually produce a rhythmic musical pattern reinforces lateralised and segregated cortico-muscular communication.This work was supported by a grant from the Australian Research Council (DP170104322)

Spatial and temporal (non)binding of audiovisual rhythms in sensorimotor synchronisation

All data are held in a public repository, available at OSF database (URL access: https://osf.io/2jr48/?view_only=17e3f6f57651418c980832e00d818072).Human movement synchronisation with moving objects strongly relies on visual input. However, auditory information also plays an important role, since real environments are intrinsically multimodal. We used electroencephalography (EEG) frequency tagging to investigate the selective neural processing and integration of visual and auditory information during motor tracking and tested the effects of spatial and temporal congruency between audiovisual modalities. EEG was recorded while participants tracked with their index finger a red flickering (rate fV = 15 Hz) dot oscillating horizontally on a screen. The simultaneous auditory stimulus was modulated in pitch (rate fA = 32 Hz) and lateralised between left and right audio channels to induce perception of a periodic displacement of the sound source. Audiovisual congruency was manipulated in terms of space in Experiment 1 (no motion, same direction or opposite direction), and timing in Experiment 2 (no delay, medium delay or large delay). For both experiments, significant EEG responses were elicited at fV and fA tagging frequencies. It was also hypothesised that intermodulation products corresponding to the nonlinear integration of visual and auditory stimuli at frequencies fV ± fA would be elicited, due to audiovisual integration, especially in Congruent conditions. However, these components were not observed. Moreover, synchronisation and EEG results were not influenced by congruency manipulations, which invites further exploration of the conditions which may modulate audiovisual processing and the motor tracking of moving objects.We thank Ashleigh Clibborn and Ayah Hammoud for their assistance with data collection. This work was supported by a grant from the Australian Research Council (DP170104322, DP220103047). OML is supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Science, Technology and Higher Education, through the national funds, within the scope of the Transitory Disposition of the Decree No. 57/2016, of 29 August, amended by Law No. 57/2017 of 19 July (Ref.: SFRH/BPD/72710/2010

Reading point-light walkers and amorphous: a TMS study

Objectives: (i) Evaluate if human actions with and without pictorial information result in comparable motor facilitation clarifying the adequacy of point-light (PL) human actions in motor observation and motor resonance research; (ii) Verify if the isolated aspects of human shape, i.e., without movement; and the isolated aspect of movement, i.e., PL in amorphous shape, are not enough for eliciting motor network response and thus that motor facilitation is specific to human action perception involving human motor and spatial configurations. Research question: Are PL human actions suitable stimuli for action observation experiments evaluating motor resonance response and what are the adequate parameters for preparing their control stimuli? Methods: Motor evoked potentials (MEPs) of M1 were recorded from 18 healthy subjects using transcranial magnetic stimulation (TMS) during presentation of full-body video clips of: everyday human actions either with (real movement - RM) or without (biological point-light - PLbio) pictorial information, scrambled moving point-lights (PLscr) and static point-lights forming a human shape (PLs). All videos were approximately 1000ms long. Peak-to-peak MEP amplitude (maximal distance) was individually averaged for each condition (RM, PLbio, PLscr, PLs). Results: rmANOVA considering MEP as dependent variable and condition as within-subject factor revealed a main effect for Stimuli (F1,17= 6.91; p=.029; np2 =.16). Specifically, Fisher LSD post hoc revealed that such effect was due to inferior MEP amplitude in PLs condition when compared to RM (p=.016), PLbio (p= .006) and PLscr (p=.047). Conclusion: Our findings account for future studies elaboration by providing information on similar CE increase during PLbio and RM observation, thus corroborating the use of human PL in motor resonate/action observation studies. Noteworthy, PLscr also engaged the motor network, which could be due to kinematic aspects of human velocity profile or anthropomorphism of non- biological agents. Observation of PLs resulted in significantly smaller MEPs. Therefore, M1 activation seems restrict to movement perception but not to human form. Thus, planning the control stimuli and task context is crucial when using PL displays in the study of human action perception and the action observation network activation

Tuning and disrupting the brain—modulating the McGurk illusion with electrical stimulation

In the so-called McGurk illusion, when the synchronized presentation of the visual stimulus /ga/ is paired with the auditory stimulus /ba/, people in general hear it as /da/. Multisensory integration processing underlying this illusion seems to occur within the Superior Temporal Sulcus (STS). Herein, we present evidence demonstrating that bilateral cathodal transcranial direct current stimulation (tDCS) of this area can decrease the McGurk illusion-type responses. Additionally, we show that the manipulation of this audio-visual integrated output occurs irrespective of the number of eye-fixations on the mouth of the speaker. Bilateral anodal tDCS of the Parietal Cortex also modulates the illusion, but in the opposite manner, inducing more illusion-type responses. This is the first demonstration of using non-invasive brain stimulation to modulate multisensory speech perception in an illusory context (i.e., both increasing and decreasing illusion-type responses to a verbal audio-visual integration task). These findings provide clear evidence that both the superior temporal and parietal areas contribute to multisensory integration processing related to speech perception. Specifically, STS seems fundamental for the temporal synchronization and integration of auditory and visual inputs. For its part, posterior parietal cortex (PPC) may adjust the arrival of incoming audio and visual information to STS thereby enhancing their interaction in this latter area

Spatial and temporal (non)binding of audio-visual stimuli: effects on motor tracking and underlying neural sensory processing

Objectives: Compare the steady-state evoked potentials (SSEPs) of spatially or temporally congruent and incongruent audio-visual stimuli and evaluate how congruency affects the motion tracking of visual stimuli. Research question: Does spatial or temporal congruency of audio-visual stimuli affect motion tracking and evoke differential SSEPs? Methods: We use EEG frequency-tagging techniques to investigate the selective neural processing and integration of visual and auditory information in the tracking of a moving stimulus and how spatial and temporal (in)congruency between the two modalities modulate these sensory neural processes and synchronization performance.Participants were instructed to track a red dot flickering at 15 Hz that oscillated horizontally with a complex trajectory on a computer screen by moving their index finger. An auditory pure tone with continuous pitch modulation at 32 Hz was presented with lateralised amplitude modulations in left and right audio channels (panning) that were, in Experiment 1, either spatially congruent or incongruent (same direction vs. opposite direction vs. no panning), and in Experiment 2, either temporally congruent or incongruent (no delay vs. medium or large delay), with the oscillating visual stimulus. Results: Both experiments yielded significant EEG responses at the visual (15 Hz) and auditory (32 Hz) tagging frequencies. Further, in Experiment 1 participants had lower performance and larger amplitudes at the auditory frequency during no panning condition. No significant correlation between the two measures was found. In Experiment 2 no changes in the amplitude of the EEG responses or in performance were found. Conclusion: The movement synchronization performance and the neural processing of visual and auditory information were not influenced by phase congruency manipulation. For spatial congruency, the moving auditory stimuli led to better performance, irrespective of congruency, when compared to the non moving sound. Importantly, there were no significant responses at 17 and 47 Hz corresponding to the intermodulation frequencies of 15 and 32 Hz, suggesting an absence of global integration of visual and auditory information. These results encourage further exploration of the conditions that may result in the selective processing of visual and auditory information and their integration in the motor tracking of moving environmental objects

Food addiction problems in college students: the relationship between weight-related variables, eating habits, and food choices

The concept of food addiction, characterized by a strong urge to overeat highly palatable foods, has gained increased research attention over the last decade. College students are a recognized risk group for manifesting an eating pathology and weight gain due to the changes in eating habits experienced during this period. However, there is a gap in the literature connecting food addiction with eating and weight variables in this population. Thus, the present study aims to characterize food addiction in a sample of college students and enlighten the relationship between food addiction, weight-variables, eating habits, and food choices in this population. A sample of 194 college students (89.2% females) aged between 18 and 32 years old (M = 20.85, SD = 2.78) completed a set of self- reported online questionnaires on Google Forms. Namely, a Sociodemographic and Anthropometric Questionnaire, a questionnaire on Food Choices Characterization, the Eating Habits Scale, and the Portuguese Yale Food Addiction Scale 2.0. Thirty (22.2%) participants presented food addiction problems. The logistic regression models utilized suggest that participants in the group with food addiction problems are more likely to seek clinical help to control weight, to consider that they should eat less food high in sugar, and to report lower food adequacy. In sum, this finding highlighted a connection between food addiction, weight dissatisfaction, eating habits, and food choices in college students, a population at risk for developing and retaining eating pathologies. Further research is essential to evaluate and implement interventions regarding food addiction, weight dissatisfaction, eating habits, and food choices in college students.This study was conducted at the Psychology Research Centre (CIPsi/UM) School of Psychology, University of Minho, supported by the Foundation for Science and Technology (FCT) through the Portuguese State Budget (UIDB/01662/2020), and by grants to Sílvia Félix (2020.07384.BD) and Eva Conceição (2020.01538.CEECIND). The funding body had no role in the design, collection, analysis, or interpretation of the data; in the writing of the manuscript; or in the decision to submit the manuscript for publication