1.Research progress of brain-computer interface application paradigms based on rapid serial visual presentation.
Jingmin SUN ; Jiayuan MENG ; Jia YOU ; Mingming YANG ; Jing JIANG ; Minpeng XU ; Dong MING
Journal of Biomedical Engineering 2023;40(6):1235-1241
Rapid serial visual presentation (RSVP) is a type of psychological visual stimulation experimental paradigm that requires participants to identify target stimuli presented continuously in a stream of stimuli composed of numbers, letters, words, images, and so on at the same spatial location, allowing them to discern a large amount of information in a short period of time. The RSVP-based brain-computer interface (BCI) can not only be widely used in scenarios such as assistive interaction and information reading, but also has the advantages of stability and high efficiency, which has become one of the common techniques for human-machine intelligence fusion. In recent years, brain-controlled spellers, image recognition and mind games are the most popular fields of RSVP-BCI research. Therefore, aiming to provide reference and new ideas for RSVP-BCI related research, this paper reviewed the paradigm design and system performance optimization of RSVP-BCI in these three fields. It also looks ahead to its potential applications in cutting-edge fields such as entertainment, clinical medicine, and special military operations.
Humans
;
Brain-Computer Interfaces
;
Electroencephalography/methods*
;
Brain/physiology*
;
Artificial Intelligence
;
Photic Stimulation/methods*
2.Representations of object animacy and real-world size in the ventral visual pathway.
Zhao-Jin CHENG ; Ning LIU ; Yao-Dong FAN ; Pin ZUO ; Hong-Ping YUAN ; Zhu XU
Acta Physiologica Sinica 2022;74(2):294-300
How the brain perceives objects and classifies perceived objects is one of the important goals of visual cognitive neuroscience. Previous research has shown that when we see objects, the brain's ventral visual pathway recognizes and classifies them, leading to different ways of interacting with them. In this paper, we summarize the latest research progress of the ventral visual pathway related to the visual classification of objects. From the perspective of the neural representation of objects and its underlying mechanisms in the visual cortex, we summarize the current research status of the two important organizational dimensions of object animacy and real-world size, provide new insights, and point out the direction of further research.
Brain Mapping/methods*
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Magnetic Resonance Imaging
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Pattern Recognition, Visual
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Photic Stimulation
;
Visual Cortex
;
Visual Pathways
3.Progresses and prospects on frequency recognition methods for steady-state visual evoked potential.
Yangsong ZHANG ; Min XIA ; Ke CHEN ; Peng XU ; Dezhong YAO
Journal of Biomedical Engineering 2022;39(1):192-197
Steady-state visual evoked potential (SSVEP) is one of the commonly used control signals in brain-computer interface (BCI) systems. The SSVEP-based BCI has the advantages of high information transmission rate and short training time, which has become an important branch of BCI research field. In this review paper, the main progress on frequency recognition algorithm for SSVEP in past five years are summarized from three aspects, i.e., unsupervised learning algorithms, supervised learning algorithms and deep learning algorithms. Finally, some frontier topics and potential directions are explored.
Algorithms
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Brain-Computer Interfaces
;
Electroencephalography/methods*
;
Evoked Potentials, Visual
;
Photic Stimulation
4.A discussion about key issues in retinal prosthesis.
Chenglin PENG ; Lu XIA ; Xing WANG ; Erxin ZHENG
Journal of Biomedical Engineering 2009;26(3):671-675
Retinitis pigmentosa (RP) and age-related macular degeneration (AMD) are two predominant causes of visual deterioration. Retinal prosthesis embeds a micro-electric chip or a micro-photoelectric diode array in the sub-retina or epi-retina, which is used to stimulate the remainder of inner retina, so as to restore some degree of sight. Retinal prosthesis has attracted most attention in the field of artificial visual function recovery, and along with deep-going research, many issues need to be resolved. In this paper, the theory of retinal prosthesis and the status quo of research in many countries are introduced, the key issues which influence the application of the retinal prosthesis are discussed in detail, and some notions and advices are presented.
Electric Stimulation Therapy
;
instrumentation
;
methods
;
Humans
;
Macular Degeneration
;
surgery
;
Photic Stimulation
;
instrumentation
;
methods
;
Prosthesis Design
;
Retinitis Pigmentosa
;
surgery
;
Visual Prosthesis
;
standards
;
trends
5.Study of Blue and Red Flash in Dark-Adapted Electroretinogram.
Sang Hyun LIM ; Young Hoon OHN
Korean Journal of Ophthalmology 2005;19(2):106-111
PURPOSE: To investigate the characteristics of the waveform generated by blue and red light stimulations in a dark-adapted electroretinogram (ERG) and those of cone responses in the dark-adapted condition. METHODS: The study subjects were 52 persons (88 eyes) with no previous medical history. The author recorded b-waves (rod response) with red light stimulation and the x-waves (dark-adapted cone response) that appeared before the b-waves. The author also recorded b-waves with blue light stimulation, which had the same amplitude as the b-waves from the red light stimulation. The differences with respect to age and gender were studied. Waveforms of the dark-adapted cone ERGs were recorded by using a digital subtraction technique. RESULTS: The x-wave always appeared before the b-wave with 0 dB (2.4 cd.s/m2) red stimulation. With blue stimulation, a b-wave equivalent to the b-wave stimulated with the red light of 0 dB intensity appeared at an average of -14.57 dB. The implicit time for the b-wave was delayed significantly for the male group. There were no significant differences between different age groups. The dark-adapted cone ERG demonstrated the waveform of a negative response followed by a series of oscillatory potentials (OPs) and a positive response. CONCLUSIONS: The cone responses were followed by the rod responses with red light stimulation of 0 dB in the dark-adapted ERG. The waveforms of the cone ERGs were obtained in dark adaptation with red and blue light stimulation.
Adolescent
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Adult
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Child
;
Dark Adaptation/*physiology
;
*Electroretinography
;
Female
;
Humans
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Male
;
Middle Aged
;
Photic Stimulation/*methods
;
Retina/*physiology
6.The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat.
Korean Journal of Ophthalmology 2011;25(1):48-53
PURPOSE: The purpose of this study was to investigate the effects of contrast display exposure on neuronal directional and spatial frequency tuning. Neuronal responses were recorded from ninety-four neurons in cortical areas 17 and 18 in two adult cats. METHODS: A multi-channel microelectrode was implanted in cortical areas 17 and 18 of two paralyzed and anaesthetized cats. Various drifting sinusoidal grating contrast displays were presented to one of the cats' eyes in the visual field. Contour plots based on the neuronal responses to the drifting sinusoidal grating displays using various contrasts (i.e., 0.4, 0.7, and 1.0) and velocities (i.e., 4.6, 13.9, 23.1, 32.3, 41.5, 50.8, and 60.0 deg/sec) were plotted as a function of the spatial frequency and the direction associated with each velocity and contrast used. RESULTS: Five parameters were extracted from these contour plots: 1) optimum response, 2) preferred direction, 3) optimum spatial frequency, 4) directional tuning width, and 5) spatial frequency bandwidth. To determine the optimal velocity, each parameter was plotted against each of the specific display contrasts used, and a 'best fit' line was established. Response amplitudes were dependent on the type of contrast utilized; however, the spatial frequency and directional tuning properties were stable for the cortical neurons assessed. CONCLUSIONS: The results of the presentation of different contrasts on neuronal directional and spatial frequency tuning are consistent with behavioral results when medium and high contrast displays are used.
Animals
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Cats
;
Contrast Sensitivity/*physiology
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Electrophysiological Phenomena
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Orientation/physiology
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Photic Stimulation/methods
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Sen
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Space Perception/physiology
;
Visual Cortex/cytology/*physiology
7.Monitoring depth of anesthesia and effect analysis in primary visual cortex of rats based on complexity of local field potential.
Xiaoyuan LI ; Li SHI ; Hong WAN ; Yuxia HU
Journal of Biomedical Engineering 2014;31(2):245-250
In the present study carried out in our laboratory, we recorded local field potential (LFP) signals in primary visual cortex (V1 area) of rats during the anesthesia process in the electrophysiological experiments of invasive microelectrode array implant, and obtained time evolutions of complexity measure Lempel-ziv complexity (LZC) by nonlinear dynamic analysis method. Combined with judgment criterion of tail flick latency to thermal stimulus and heart rate, the visual stimulation experiments are carried out to verify the reliability of anesthetized states by complexity analysis. The experimental results demonstrated that the time varying complexity measures LZC of LFP signals of different channels were similar to each other in the anesthesia process. In the same anesthesia state, the difference of complexity measure LZC between neuronal responses before and after visual stimulation was not significant. However, the complexity LZC in different anesthesia depths had statistical significances. Furthermore, complexity threshold value represented the depth of anesthesia was determined using optimization method. The reliability and accuracy of monitoring the depth of anesthesia using complexity measure LZC of LFP were all high. It provided an effective method of realtime monitoring depth of anesthesia for craniotomy patients in clinical operation.
Anesthesia
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methods
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Animals
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Evoked Potentials, Visual
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Microelectrodes
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Monitoring, Physiologic
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Nonlinear Dynamics
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Photic Stimulation
;
Rats
;
Reproducibility of Results
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Visual Cortex
;
drug effects
8.ERP spatio-temporal analysis for perception of motion-in-depth: the effect of size factor on cognition.
Journal of Biomedical Engineering 2009;26(2):394-399
By means of continuous visual stimulation to simulate the motion-in-depth course where object was approaching to observer gradually, we studied the event-related potentials (ERP) response in that course. This article was directed to the effect of object size factor on the ERP of motion-in-depth perception. The subjects recruited were 9 health men, aged 22-29 years. The results illustrated that, in motion-in-depth course, the main components were P80, N100, P140, N220, P300, N350, and P400. They mainly appeared in the frontal area, occipital area and occipital-parietal area; some of them showed near by the parietal-temporal or occipital-temporal area. Among these components, N220 was most closely related to the perception of motion-in-depth. From the data analysis in 500 ms, bigger object led to earlier and stronger response.
Adult
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Cognition
;
physiology
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Depth Perception
;
physiology
;
Electroencephalography
;
Evoked Potentials
;
physiology
;
Humans
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Male
;
Motion Perception
;
physiology
;
Photic Stimulation
;
methods
;
Young Adult
9.Effects of temporal frequency on the sweep pattern visual evoked response acuity.
Rui-Jue LIU ; Jie-Min CHEN ; Wen-Tao XIA ; Li-Hua FAN ; Guang-You ZHU
Journal of Forensic Medicine 2009;25(6):409-411
OBJECTIVE:
To investigate the changes of sweep pattern visual evoked response (SPVER) acuity in different temporal frequency.
METHODS:
The persons were collected and divided into the low visual acuity group (71 eyes) and the high visual acuity group (92 eyes). The eyes were stimulated with different temporal frequency (8.5 Hz, 10 Hz, 15 Hz and 20 Hz, respectively) and the same series of spatial frequency. The accuracy of SPVER acuity in different temporal frequency was evaluated by compare the SPVER acuity with the subjective vision.
RESULTS:
In the low visual acuity group, there was a good correlation between the SPVER acuity and the subjective vision applying the spatial frequency of the group. In the high visual acuity group, the SPVER acuity was lower than the subjective vision. SPVER acuity showed a good correlation with the subjective vision at the temporal frequency of 10 Hz in two groups.
CONCLUSION
The temporal frequency can influence SPVER accuracy, so it is necessary to select the suitable stimulation condition in forensic practice.
Adult
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Evoked Potentials, Visual/physiology*
;
Female
;
Forensic Medicine/methods*
;
Humans
;
Male
;
Photic Stimulation/methods*
;
Time Factors
;
Vision Disorders/physiopathology*
;
Vision Tests/methods*
;
Visual Acuity/physiology*
;
Young Adult
10.Brain Activation in Response to Visually Evoked Sexual Arousal in Male-to-Female Transsexuals: 3.0 Tesla Functional Magnetic Resonance Imaging.
Seok Kyun OH ; Gwang Won KIM ; Jong Chul YANG ; Seok Kwun KIM ; Heoung Keun KANG ; Gwang Woo JEONG
Korean Journal of Radiology 2012;13(3):257-264
OBJECTIVE: This study used functional magnetic resonance imaging (fMRI) to contrast the differential brain activation patterns in response to visual stimulation with both male and female erotic nude pictures in male-to-female (MTF) transsexuals who underwent a sex reassignment surgery. MATERIALS AND METHODS: A total of nine healthy MTF transsexuals after a sex reassignment surgery underwent fMRI on a 3.0 Tesla MR Scanner. The brain activation patterns were induced by visual stimulation with both male and female erotic nude pictures. RESULTS: The sex hormone levels of the postoperative MTF transsexuals were in the normal range of healthy heterosexual females. The brain areas, which were activated by viewing male nude pictures when compared with viewing female nude pictures, included predominantly the cerebellum, hippocampus, putamen, anterior cingulate gyrus, head of caudate nucleus, amygdala, midbrain, thalamus, insula, and body of caudate nucleus. On the other hand, brain activation induced by viewing female nude pictures was predominantly observed in the hypothalamus and the septal area. CONCLUSION: Our findings suggest that distinct brain activation patterns associated with visual sexual arousal in postoperative MTF transsexuals reflect their sexual orientation to males.
Adult
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Arousal/physiology
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Brain Mapping/*methods
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Erotica
;
Female
;
Gonadal Steroid Hormones/blood
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Humans
;
Image Processing, Computer-Assisted
;
Magnetic Resonance Imaging/*methods
;
Male
;
Middle Aged
;
Photic Stimulation
;
Transsexualism/*psychology