visual stimuli
Recently Published Documents


TOTAL DOCUMENTS

2744
(FIVE YEARS 724)

H-INDEX

106
(FIVE YEARS 15)

Author(s):  
Irving Remy ◽  
Thomas Schwitzer ◽  
Éliane Albuisson ◽  
Raymund Schwan ◽  
Julien Krieg ◽  
...  
Keyword(s):  

2022 ◽  
Vol 15 ◽  
Author(s):  
Xiaowei Zheng ◽  
Guanghua Xu ◽  
Yuhui Du ◽  
Hui Li ◽  
Chengcheng Han ◽  
...  

This study aimed to explore whether there was an effect on steady-state visual evoked potential (SSVEP) visual acuity assessment from the oblique effect or the stimulus orientation. SSVEPs were induced by seven visual stimuli, e.g., the reversal sinusoidal gratings with horizontal, two oblique, and vertical orientations, reversal checkerboards with vertical and oblique orientations, and oscillating expansion-contraction concentric-rings, at six spatial frequency steps. Ten subjects participated in the experiment. Subsequently, a threshold estimation criterion was used to determine the objective SSVEP visual acuity corresponding to each visual stimulus. Taking the SSVEP amplitude and signal-to-noise-ratio (SNR) of the fundamental reversal frequency as signal characteristics, both the SSVEP amplitude and SNR induced by the reversal sinusoidal gratings at 3.0 cpd among four stimulus orientations had no significant difference, and the same finding was also shown in the checkerboards between vertical and oblique orientation. In addition, the SSVEP visual acuity obtained by the threshold estimation criterion for all seven visual stimuli showed no significant difference. This study demonstrated that the SSVEPs induced by all these seven visual stimuli had a similarly good performance in evaluating visual acuity, and the oblique effect or the stimulus orientation had little effect on SSVEP response as well as the SSVEP visual acuity.


2022 ◽  
Author(s):  
Constantinos Eleftheriou

The goal of this protocol is to assess visuomotor learning and motor flexibility in freely-moving mice, using the Visiomode touchscreen platform. Water-restricted mice first learn to associate touching a visual stimulus on the screen with a water reward. They then learn to discriminate between different visual stimuli on the touchscreen by nose-poking, before asked to switch their motor strategy to forelimb reaching.


2022 ◽  
Author(s):  
Babu Chinta ◽  
Moorthi M

Abstract Brain Computer Interface (BCI) is one of the fast-growing technological trends, which finds its applications in the field of the healthcare sector. In this work, 16 electrodes of Electroencephalography (EEG) placed according to the 10-20 electrode system are used to acquire the EEG signals. A BCI with EEG based imagined word prediction using Convolutional Neural Network (CNN) is modeled and trained to recognize the words imagined through the EEG brain signal, where the CNN model Alexnet and Googlenet are able to recognize the words due to visual stimuli namely, up, down, right, left and up to ten words. The performance metrics are improved with the Morlet Continuous wavelet transform applied at the pre-processing stage, with seven extracted features such as mean, standard deviation, skewness, kurtosis, bandpower, root mean square, and Shannon entropy. Based on the testing, Alexnet transfer learning model performed better as compared to Googlenet transfer learning model, as it achieved an accuracy of 90.3%, recall, precision, and F1 score of 91.4%, 90%, and 90.7% respectively for seven extracted features. However, the performance metrics decreased when the number of extracted features was reduced from seven to four, to 83.8%, 84.4%, 82.9%, and 83.6% respectively. This high accuracy further paves the way to future work on cross participant analysis, plan to involve a larger number of participants for testing and to enhance the deep learning neural networks to create the system developed to be suitable for EEG based mobile applications, which helps to identify what the words are imagined to be uttered by the speech-disabled persons.


Author(s):  
RONI KAE MERY PRANCHIS ◽  
AJUNTHA KUPPAN

Visual images are increasingly appearing in learning and teaching resources, delivered across a range of media in a variety of formats: digitally Web-based material and multimedia as well as print and as transparencies. The proliferation of image-rich resources is due to the wide availability of digital images and access to the technology and graphics software that facilitates the creation and delivery of visual materials. The main aim of this research is to investigate the role of visual stimuli in enhancing writing skills among USM undergraduates who are taking Tamil as foreign language. Writing is an important skill often emphasized among foreign language learners. However, most foreign language learners face difficulties to pen down their thoughts. The respondents of this research are pursuing LAT 300 (Tamil Language III) course at the School of Languages, Literacies and Translation and are divide into two groups, experimental and control group. The methods used is written assignment; topic with visual stimuli for experimental group and topic without stimuli for control group. The written assignments were graded using the university’s grading rubric. In the questionnaire, the respondents were also asked to give feedback on the use of visual stimuli in writing. The findings of this study revealed that the experimental group performed better as they were given visuals. The experimental group respondents highlighted that they needed stimuli to motivate and trigger their background knowledge on the essay topics. It is hoped that this study will aid language teachers and practitioners to utilize visuals as a support in the teaching of Tamil Language as foreign language.


2021 ◽  
Vol 3 (2) ◽  
pp. 159-173
Author(s):  
Ugur Tuztasi ◽  
◽  
Pinar Koc

As well as a design process, experimental practices in architectural education are associated with the analytical approaches of visual thinking and visual reasoning. The main purpose of this study was to explore creative methods for devising a vertical construction through visual reasoning. In terms of experimental practices, design research is based on exploration while the primary research area in architecture is reframed by constantly renewed approaches. Accordingly, the hypothesis of this study was that creative methods would improve when the creation of a vertical construction in architectural education is nourished by visual stimuli. The study searched for a construction that plasticized the vertical spatiality of Sivas Grand Mosque’s minaret. The method was shaped by a prerequisite dialogue that rests on visual stimuli. The expected outcome of this dialogue was that the minaret as a pure form would be subjected to an abstraction and, a design proposal then developed for its current structural problems. The results indicated a two-fold appreciation of design. First, when the minaret was maintained within the idea of stabilization rather than being construed as a pure form, the search for a creative method of vertical construction was handled in the context of static preservation. Second, when Sivas Grand Mosque’s minaret as an imaginary design tool was construed as a pure form and the abstraction level increased through visual reasoning, the outcomes gradually demonstrated an approach akin to experimental practices


2021 ◽  
Vol 38 (6) ◽  
pp. 1689-1698
Author(s):  
Suat Toraman ◽  
Ömer Osman Dursun

Human emotion recognition with machine learning methods through electroencephalographic (EEG) signals has become a highly interesting subject for researchers. Although it is simple to define emotions that can be expressed physically such as speech, facial expressions, and gestures, it is more difficult to define psychological emotions that are expressed internally. The most important stimuli in revealing inner emotions are aural and visual stimuli. In this study, EEG signals using both aural and visual stimuli were examined and emotions were evaluated in both binary and multi-class emotion recognitions models. A general emotion recognition model was proposed for non-subject-based classification. Unlike in previous studies, a subject-based testing was performed for the first time in the literature. Capsule Networks, a new neural network model, has been developed for binary and multi-class emotion recognition. In the proposed method, a novel fusion strategy was introduced for binary-class emotion recognition and the model was tested using the GAMEEMO dataset. Binary-class emotion recognition achieved a classification accuracy which was 10% better than the classification performance achieved in other studies in the literature. Based on these findings, we suggest that the proposed method will bring a different perspective to emotion recognition.


2021 ◽  
pp. 004728752110576
Author(s):  
Huahua Li ◽  
Mimi Li ◽  
Guyang Lin ◽  
Hanqin Qiu

The notion of multifaceted image, composed of cognitive, affective, and sensory dimensions, has attracted growing scholarly interest in recent years. However, general understanding of the roles of the senses (i.e., sight, hearing, taste, smell, and touch) in image processing remains scarce. Little attention has also been paid to the effects of visual stimuli related to design features on the construction of multifaceted image. This study investigated viewers’ perceived multifaceted destination image upon exposure to different photo formats (i.e., animated vs. static). A mixed method approach was employed to collect data using a between-subjects experimental design. Findings revealed that moving visual presentation exert stronger impacts on three image dimensions in several aspects and associations were also observed between photo contents and sensory arousal. Results enrich the body of knowledge on destination image in terms of image structure and the features of visual stimuli. Practical implications are discussed as well.


2021 ◽  
Vol 12 ◽  
Author(s):  
John Waterston ◽  
Luke Chen ◽  
Kate Mahony ◽  
Jamila Gencarelli ◽  
Geoff Stuart

Persistent postural perceptual dizziness (PPPD) is a common chronic vestibular disorder characterized by persistent vestibular symptoms, including postural instability and non-spinning vertigo, which is aggravated by motion, upright posture and moving or complex visual stimuli. In our review of 198 cases seen over a 5 year period, we have confirmed a number of common precipitating conditions for PPPD, including anxiety disorders and vestibular migraine. Vestibular abnormalities, including a unilateral loss of vestibular hypofunction and isolated otolith abnormalities, were found on investigation in just under half the cases. The use of cognitive behavioral therapy (CBT) as a treatment for PPPD resulted in impressive reductions in anxiety and measures of dizziness over follow up periods of up to 6 months.


2021 ◽  
Vol 15 ◽  
Author(s):  
Jiahao Liu ◽  
Qi Zhang ◽  
Maojin Liang ◽  
Yajing Wang ◽  
Yuebo Chen ◽  
...  

Objective: Vestibular migraine (VM) is one of the most common causes of recurrent vertigo, but the neural mechanisms that mediate such symptoms remain unknown. Since visual symptoms and photophobia are common clinical features of VM patients, we hypothesized that VM patients have abnormally sensitive low-level visual processing capabilities. This study aimed to investigate cortex abnormalities in VM patients using visual evoked potential (VEP) and standardized low-resolution brain electromagnetic tomography (sLORETA) analysis.Methods: We employed visual stimuli consisting of reversing displays of circular checkerboard patterns to examine “low-level” visual processes. Thirty-three females with VM and 20 healthy control (HC) females underwent VEP testing. VEP components and sLORETA were analyzed.Results: Patients with VM showed significantly lower amplitude and decreased latency of P1 activation compared with HC subjects. Further topographic mapping analysis revealed a group difference in the occipital area around P1 latency. sLORETA analysis was performed in the time frame of the P1 component and showed significantly less activity (deactivation) in VM patients in the frontal, parietal, temporal, limbic, and occipital lobes, as well as sub-lobar regions. The maximum current density difference was in the postcentral gyrus of the parietal lobe. P1 source density differences between HC subjects and VM patients overlapped with the vestibular cortical fields.Conclusion: The significantly abnormal response to visual stimuli indicates altered processing in VM patients. These findings suggest that abnormalities in vestibular cortical fields might be a pathophysiological mechanism of VM.


Sign in / Sign up

Export Citation Format

Share Document