In accounts of the development and progression of psychophysical disorders such as Hereditary Spastic Paraplegia (HSP) and Facioscapulohumeral Muscular Dystrophy (FSHD), the role of beliefs, perceptions, and behaviora...In accounts of the development and progression of psychophysical disorders such as Hereditary Spastic Paraplegia (HSP) and Facioscapulohumeral Muscular Dystrophy (FSHD), the role of beliefs, perceptions, and behavioral patterns has often been overlooked in favor of a genetically determinist paradigm. This paper explores the impact of NeuroPhysics Treatment (NPT) on patients with HSP and FSHD. Through a series of clinical case reports, I demonstrate how intensive four-day NPT sessions can lead to rapid restoration of lost functions, challenging the conventional view of these disorders. I hypothesize that, by modulating the patient’s perceptual and behavioral frameworks, NPT facilitates the emergence of healthier patterns, suggesting that environmental and psychological factors significantly influence the manifestation and management of these conditions. These findings indicate that the role of genetic inheritance may be overstated and that beliefs and perceptions could play a crucial role in the evolution of psychophysical disorders. The implications of this research extend beyond the traditional treatment paradigms, advocating for a more holistic approach that integrates the psychophysical dimensions of health and challenges the deterministic perspective of genetic inheritance.展开更多
The brain is a unique organization in nature, having the psychic activity, which is expressed in subjective states: thoughts, feelings, emotions. Knowledge of the nature of mental activity of the brain is the most urg...The brain is a unique organization in nature, having the psychic activity, which is expressed in subjective states: thoughts, feelings, emotions. Knowledge of the nature of mental activity of the brain is the most urgent and the most challenging task of physiology. Historically the neurophysiology developed on the basis of physical and chemical laws discovered in an inanimate nature. Our investigation is devoted towards the origin of a human subjective state, and presents a new methodology for studying of the nature psychic brain activity. We have established the existence of physical phenomena unique for the living brain so-called “psychogenic field”, which reflects the expressed psychic state of human brain. The subjective state of a human being was shown to affect remotely the physicochemical properties of the blood. An original schematic diagram is presented to describe the formation of the brain psychic activity. This approach is based on the feedback influence of a psychogenic field on neuronal molecular processes (self-induction in the brain). We propose a paradigm for the origin of psychic state and possible existence of the fields, which are unique for the brain. The presented scheme and paradigm of systemic organization of psychic activity of the brain are a prerequisite for the subsequent development of the theory consciousness.展开更多
Leakage currents, tiny currents flowing from an everyday-life appliance through the body to the ground, can cause a non-adequate perception （called electrocutaneous sensation, ECS） or even pain and should be avoided...Leakage currents, tiny currents flowing from an everyday-life appliance through the body to the ground, can cause a non-adequate perception （called electrocutaneous sensation, ECS） or even pain and should be avoided. Safety standards for low-frequency range are based on experimental results of current thresholds of electrocutaneous sensations, which however show a wide range between about 50 pA （rms） and 1000 μA （rms）. In order to be able to explain these differences, the perception threshold was measured repeatedly in experiments with test persons under identical experimental setup, but by means of different methods （measuring strategies）, namely： direct adjustment, classical threshold as amperage of 50% perception probability, and confidence rating procedure of signal detection theory. The current is injected using a I cm2 electrode at the highly touch sensitive part of the index fingertip. These investigations show for the first time that the threshold of electrocutaneous sensations is influenced both by adaptation to the non-adequate stimulus and individual, emotional factors. Theretbre, classical methods, on which the majority of the safety investigations are based, cannot be used to determine a leakage current threshold. The confidence rating procedure of the modem signal detection theory yields a value of 179.5 μA （rms） at 50 Hz power supply net frequency as the lower end of the 95% confidence range considering the variance in the investigated group. This value is expected to be free of adaptation influences, and is distinctly lower than the European limits and supports the stricter regulations of Canada and USA.展开更多
This research implements a random dot kinematogram(RDK)using virtual reality(VR)and analyzes the results based on normal subjects.Visual motion perception is one of visual functions localized to a specific cortical ar...This research implements a random dot kinematogram(RDK)using virtual reality(VR)and analyzes the results based on normal subjects.Visual motion perception is one of visual functions localized to a specific cortical area,the human motion perception area(human analogue for the middle temporal/middle superior temporal area)located in the parieto–occipito–temporal junction of the human brain.The RDK measures visual motion perception capabilities.The stimuli in conventional RDK methods are presented using a monitor screen,so these devices require a spacious dark room for installation and use.Recently,VR technology has been implemented in different medical domains.The test method proposed in this study include a VR-based RDK that can independently measure human motion perception abilities without any spatial constraints via a VR head-mounted display.Subsequently,the VR-based RDK was implemented,and the visual perception abilities of the normal subjects were measured based on varying coherences.In both screen-and VR-based RDK tests,the easier the stimulus is,the higher the correct answer rate and the shorter the reaction time.No significant differences in coherence thresholds were observed between the two test methods.The VRbased RDK proposed in this study can be used as a diagnosis tool for visual motion perception and neurodegenerative disorders affecting the posterior region of the brain.展开更多
To produce a smoother and more natural interpolated image, and to preserve and enhance original image details, we defined three perception-based local statistic parameters, namely contrast, noise visibility, and edge ...To produce a smoother and more natural interpolated image, and to preserve and enhance original image details, we defined three perception-based local statistic parameters, namely contrast, noise visibility, and edge strength based on three psychophysical principles, including Weber’s Law, Fechner’s Law, and Stevens’ Power Law, and integrated these parameters into a fuzzy logic system to set up an advanced image interpolation algorithm. Application of this algorithm to detect edge behaviors and local statistical information of images demonstrated better noise removal ability and obtained sharper edges than traditional image interpolation algorithems such as nearest neighbor, bilinear and bicubic interpolation methods.展开更多
Anomalies in decision over time (e.g., “hyperbolic time discounting”) and under risk (e.g., Allais paradox and hyperbolic probability discounting) have been attracting attention in behavioral and neuroeconomics. We ...Anomalies in decision over time (e.g., “hyperbolic time discounting”) and under risk (e.g., Allais paradox and hyperbolic probability discounting) have been attracting attention in behavioral and neuroeconomics. We have proposed that psychophysical time commonly explains anomalies in both decisions (Takahashi, 2011, Physica A;Takahashi et al., 2012, J Behav Econ & Finance). By adopting the q-exponential time and probability discounting models, our psychophysical and behavioral economic experiment confirmed that nonlinear distortion of psychophysical time is a common cause of the anomalies in decision both over time and under risk (i.e., intertemporal choice and decision under risk). Implications for psychophysical neuroeconomics and econophysics are discussed.展开更多
Mathematical frameworks of quantum theory have recently been adopted in cognitive and behavioral sciences, to explain the violations of normative decision theory and anomalies in cognition. However, to date, no study ...Mathematical frameworks of quantum theory have recently been adopted in cognitive and behavioral sciences, to explain the violations of normative decision theory and anomalies in cognition. However, to date, no study has attempted to explore neural implementations of such “quantum-like” information processing in the brain. This study demonstrates that neural population coding of information with nonlinear neural response functions can account for such “quantum” information processing in decision-making and cognition. It is also shown that quantum decision theory is a special case of more general population vector cording theory. Future applications of the present theory in the rapidly evolving field of “psychophysical neuroeconomics” are also discussed.展开更多
We developed a psychophysical paradigm for the clinical assessment of the contrast sensitivity (CS) mediated by the ON- and OFF-systems of the Magnocellular and Parvocellular pathways. We designed a stimulus consideri...We developed a psychophysical paradigm for the clinical assessment of the contrast sensitivity (CS) mediated by the ON- and OFF-systems of the Magnocellular and Parvocellular pathways. We designed a stimulus considering two dimensions: two spatial frequencies (0.5 and 4.5 cpd) and two temporal rates of flicker (33 ms and 1500 ms). To evidence the ON- and OFF responses, the CS was measured for two polarities of light with luminance changes of 0.6 dB steps above and below the medium luminance grey background. We tested 38 healthy volunteers. The results shows that Magnocellular contrast sensitivity was higher than Parvocellular for the 33 ms flickering stimulus and the Parvocellular contrast sensitivity was higher than Magnocellular for 1500 ms stimuli. The reliability of the test was checked and confirmed. We concluded that the test performs a rapid measurement of the CS mediated by the ON and OFF systems of Magnocellular and Parvocellular pathways. It is useful in clinical protocols due to its high sensitivity and good reliability.展开更多
Nowadays, there is a great need to investigate the effects of fatigue on physical as well as mental performance. The issues that are generally associated with extreme fatigue are that one can easily lose one’s focus ...Nowadays, there is a great need to investigate the effects of fatigue on physical as well as mental performance. The issues that are generally associated with extreme fatigue are that one can easily lose one’s focus while performing any particular activity whether it is physical or mental and this decreases one’s motivation to complete the task at hand efficiently and successfully. In the same line of thought, myriads of research studies posited the negative effects of fatigue on mental performance, and most techniques to induce fatigue to require normally long-time and repetitive visual search tasks. In this study, a visual search algorithm task was devised and customized using performance measures such as <em>d</em>’ (<strong>d-prime</strong>) and Speed Accuracy Trade-Off (<strong>SATF</strong>) as well as <strong>ROC</strong> analysis for classifier performance. The visual search algorithm consisted of distractors (<strong>L</strong>) and a target (<strong>T</strong>) whereby human participants had to press the appropriate keyboard button as fast as possible if they notice a target or not upon presentation of a visual stimulus. It was administered to human participants under laboratory conditions, and the reaction times, as well as accuracy of the participants, were monitored. It was found that the test image Size35Int255 was the best image to be used in terms of sensitivity and AUC (Area under Curve). Therefore, ongoing researches can use these findings to create their visual stimuli in such a way that the target and distractor images follow the size and intensity characteristics as found in this research.展开更多
Background:Stereoscopic Vision uses the disparity between the two images received by the two eyes in order to create a tridimensional representation.With this study,we aimed at providing an estimate of binocular visio...Background:Stereoscopic Vision uses the disparity between the two images received by the two eyes in order to create a tridimensional representation.With this study,we aimed at providing an estimate of binocular vision at a level prior to disparity processing.In particular,we wanted to assess the spatial properties of the visual system for detecting interocular correlations(IOC).Methods:We developed dichoptic stimuli,made of textures which IOC is sinusoidally modulated at various correlation spatial frequencies.Then,we compared the sensitivity to these stimuli to the sensitivity to analogous stimuli with disparity modulation.Results:We observed that IOC sensitivity presents a low-pass/band-pass profile and increases as a function of presentation duration and contrast,in a similar way as disparity sensitivity.Conclusions:IOC sensitivity is weakly-though significantly-correlated with disparity sensitivity in the general population,which suggests that it could provide a marker for binocular vision,prior to disparity processing.展开更多
Background:The human visual system can use binocular disparity to make depth judgements.Previous studies looking at the normal population have found a wide range in ability to perform depth-polarity tasks.We explored ...Background:The human visual system can use binocular disparity to make depth judgements.Previous studies looking at the normal population have found a wide range in ability to perform depth-polarity tasks.We explored if these large individual differences are also present when using a depth increment paradigm,and if they depend on the sign of disparity.Methods:Stereoacuity for detecting a wedge-shaped surface in a field of dots was measured in 53 adults(28 males)with normal vision.To better understand the variance in stereoacuity in the sample,for 18 subjects we measured stereo cuity with disparity noise added to the stimulus.Stereoacuity was unaffected at low levels of stimulus noise but beyond a critical value,it increased with the standard deviation of the noise.At this point the stimulus noise is equivalent to the internal noise of the subject.Stereoacuity measured at high stimulus noise levels reflects the efficiency with which a noisy input is processed by the visual system.We derived both parameters by fitting the linear amplifier model.Results:Stereoacuity ranged from 24 to 275 arc seconds.We found population differences in stereoacuity were explained by variation in both processing efficiency and internal noise levels.There was a tendency for higher task performance for crossed disparities compared to uncrossed disparities.Within subject sensitivity differences between crossed and uncrossed disparity were due to a higher efficiency when processing one direction.There was a trend for subjects with equal acuity for the two directions to have an increase in processing efficiency compensating for higher internal noise levels for that direction.Conclusions:Overall,our results show that the individual differences in stereoacuity for depth increment tasks can be attributed to variances in both the quality of the received input and the efficiency of processing of disparity-processing mechanisms.展开更多
The polar surface area of a molecule is currently defined as the surface sum over all polar atoms, primarily oxygen and nitrogen, also including their attached hydrogens (named PSA1 in the present study). Some authors...The polar surface area of a molecule is currently defined as the surface sum over all polar atoms, primarily oxygen and nitrogen, also including their attached hydrogens (named PSA1 in the present study). Some authors also include sulfur and phosphor (PSA3). The slight modification suggested here is based on the fact that it is difficult to consider, on a theoretical point of view, hexavalent S and pentavalents N and P as polar atoms. Indeed, in these cases, all their peripheral electrons are involved in bondings. We propose to define PSA2 using the initial definition extended to O, S, N, P, with the exception of hexavalent S and pentavalents N and P. In order to test this hypothesis, the three expressions PSA1, PSA2 and PSA3 have been applied in a QSAR to a physiological phenomenon called comfort olfactory perceived intensity, for the human responses to 186 odorants (QSAR stands for Quantitative Structure Activity Relationship). The PSA2 expression has been selected as the more suitable, associated with two other molecular properties (molar refraction and Van der Waals molecular volume).展开更多
Stochastic resonance phenomenon in the biological sensory systems has been studied through the signal detection theories and the psychophysical experiments. In this paper, sensory systems are considered as a threshold...Stochastic resonance phenomenon in the biological sensory systems has been studied through the signal detection theories and the psychophysical experiments. In this paper, sensory systems are considered as a threshold detector including the receiver part and the classifier part. Compared with conventional models regarding the receiver part of sensory system as a linear or single non-linear system, a summing network was constructed by MacCulloch-Pitts neurons to simulate the receiver part. The simulation results show that the relevant index of the detectability of signal exhibit the stochastic resonance behaviours. The psychophysical experiments were carried out through the 2IFC (two interval two alternative forced choice) method. The experimental results qualitatively verify the conclusion in accordance with the theoretical model. These works give a proof that stochastic resonance is not only epiphenonmenon in sensory systems.展开更多
Lack of temperature sensation of myoelectric prosthetic hand limits the daily activities of amputees.To this end,a noninvasive temperature sensation method is proposed to train amputees to sense temperature with psych...Lack of temperature sensation of myoelectric prosthetic hand limits the daily activities of amputees.To this end,a noninvasive temperature sensation method is proposed to train amputees to sense temperature with psychophysical sensory substitution.In this study,22 healthy participants took part besides 5 amputee participants.The duration time of the study was 31 days with five test steps according to the Leitner technique.An adjustable temperature mug and a Peltier were used to change the temperature of the water/phantom digits to induce temperature to participants.Also,to isolate the surroundings and show colors,a Virtual Reality(VR)glass was employed.The statistical results conducted are based on the response of participants with questionnaire method.Using Chi-square tests,it is concluded that participants answer the experiment significantly correctly using the Leitner technique(P value<0.05).Also,by applying the“Repeated Measures ANOVA”,it is noticed that the time of numbness felt by participants had significant(P value<0.001)difference.Participants could remember lowest and highest temperatures significantly better than other temperatures(P value<0.001);furthermore,the well-trained amputee participant practically using the prosthesis with 72.58%could identify object’s temperature with only once time experimenting the color temperature.展开更多
The study aims to highlight the contribution of sport as a tool for preventing early school leaving and developing psychophysical well-being.School,territory and sports association can,with appropriate institutional p...The study aims to highlight the contribution of sport as a tool for preventing early school leaving and developing psychophysical well-being.School,territory and sports association can,with appropriate institutional partnership actions,implement training interventions in this sense.Through an analysis of the scientific literature we want to highlight the important value of sports practice especially in school age.Organized sports activities contribute to the development of skills related to socio-relational well-being.Full awareness of one’s own cognitive and social skills allows improving self-perception.Sport,therefore,becomes a tool for preventing and contrasting early school leaving,a real protective factor that limits the decrease in motivation to school attendance and favors school performance.展开更多
<strong>Background:</strong> Nurses are very important frontline health care professionals as they spend more time with patients than other professionals. This is even more so at this critical time of the ...<strong>Background:</strong> Nurses are very important frontline health care professionals as they spend more time with patients than other professionals. This is even more so at this critical time of the COVID-19 pandemic. The nursing profession is facing great challenges in coping with the pandemic as they are more vulnerable to exposure and infection with the disease. Kuwait is not spared from the global pandemic which has put the health sector under immense pressure. Because COVID-19 is highly transmissible and deadly, it poses a huge health risk to nurses and has a huge impact on their cognitive, emotional, behavioural and physical dimensions. <strong>Aim:</strong> The study aims to explore the positive and negative emotions and feelings of staff nurses while giving care to COVID-19 patients. <strong>Materials and Methods:</strong> A descriptive cross-sectional study was carried out. 300 nurses from different general hospitals, field hospitals, and quarantine facilities in Kuwait participated in the study. A questionnaire was used to collect the data. <strong>Results:</strong> The findings show that for the cognitive evaluation, 72% were moderately affected, for the emotional evaluation 51.3% and 44% were moderately and mildly affected respectively, for the behavioural evaluation, 66.7% were severely affected, and for the physical evaluation, 43.3% and 31.7% were moderately and severely affected respectively. Prolonged working hours has a highly significant negative correlation to emotional (<em>r</em> <span style="white-space:nowrap;">−</span>0.165), behavioral (<em>r</em> <span style="white-space:nowrap;">−</span>0.177) and physical (<em>r</em> <span style="white-space:nowrap;">−</span>0.155) dimension of the nurses at 0.01 level using Spearman’s correlation. <strong>Conclusion:</strong> The study concluded that the COVID-19 pandemic has affected the psychophysical dimensions of staff nurses.展开更多
We consider the psychophysical experiments in which the test subject’s binary reaction is determined by the prescribed exposure duration to a stimulus and a random variable subjective threshold. For example, when a s...We consider the psychophysical experiments in which the test subject’s binary reaction is determined by the prescribed exposure duration to a stimulus and a random variable subjective threshold. For example, when a subject is exposed to a millimeter wave beam for a prescribed duration, the occurrence of flight action is binary (yes or no). In experiments, in addition to the binary outcome, the actuation time of flight action is also recorded if it occurs;the delay from the initiation time to the actuation time of flight action is the human reaction time, which is not measurable. In this study, we model the random subjective threshold as a Weibull distribution and formulate an inference method for estimating the human reaction time, from data of prescribed exposure durations, binary outcomes and actuation times of flight action collected in a sequence of tests. Numerical simulations demonstrate that the inference of human reaction time based on the Weibull distribution converges to the correct value even when the underlying true model deviates from the inference model. This robustness of the inference method makes it applicable to real experimental data where the underlying true model is unknown.展开更多
The visual system continuously adapts to the statistical properties of the environment. Existing evidence shows a close resemblance between deep convolutional neural networks(CNNs) and primate visual stream in neural ...The visual system continuously adapts to the statistical properties of the environment. Existing evidence shows a close resemblance between deep convolutional neural networks(CNNs) and primate visual stream in neural selectivity to naturalistic textures above the primary visual processing stage. This study delves into the mechanisms of perceptual learning in CNNs,focusing on how they assimilate the high-order statistics of natural textures. Our results show that a CNN model achieves a similar performance improvement as humans, as manifested in the learning pattern across different types of high-order image statistics. While L2 was the first stage exhibiting texture selectivity, we found that stages beyond L2 were critically involved in learning. The significant contribution of L4 to learning was manifested both in the modulations of texture-selective responses and in the consequences of training with frozen connection weights. Our findings highlight learning-dependent plasticity in the mid-to-high-level areas of the visual hierarchy. This research introduces an AI-inspired approach for studying learning-induced cortical plasticity, utilizing DCNNs as an experimental framework to formulate testable predictions for empirical brain studies.展开更多
In the information processing procedure of stereo vision, theuniqueness constraint has been used as one of the constraints to solve the "correspondence problem". While the uniqueness constraint is valid in m...In the information processing procedure of stereo vision, theuniqueness constraint has been used as one of the constraints to solve the "correspondence problem". While the uniqueness constraint is valid in most cases, whether it is still valid in some particular stimulus configuration (such as Panum's limiting case) has been a problem of widespread debate for a long time. To investigate the problem, we adopted the Panum's limiting case as its basic stimulus configuration, and delved into the phenomenon of binocular fusion from two distinct aspects: visual direction and orientation disparity. The results show that in Panum's limiting case binocular fusion does not comply with the rules governing regular binocular fusion as far as visual direction and orientation disparity are concerned. This indicates that double fusion does not happen in Panum's limiting case and that the uniqueness constraint is still valid.展开更多
Although hundreds of thousands of patients seek medical help annually for disor-ders of taste and smell, relatively few medical practitioners quantitatively test their patients' chemosensory function, taking their...Although hundreds of thousands of patients seek medical help annually for disor-ders of taste and smell, relatively few medical practitioners quantitatively test their patients' chemosensory function, taking their complaints at face value. This is clearly not the approach paid to patients complaining of visual, hearing, or balance problems. Accurate chemosensory testing is essential to establish the nature, degree, and veracity of a patient's complaint, as well as to aid in counseling and in monitoring the effectiveness of treatment strategies and de-cisions. In many cases, patients perseverate on chemosensory loss that objective assessment demonstrates has resolved. In other cases, patients are malingering. Olfactory testing is crit-ical for not only establishing the validity and degree of the chemosensory dysfunction, but for helping patients place their dysfunction into perspective relative to the function of their peer group. It is well established, for example, that olfactory dysfunction is the rule, rather than the exception, in members of the older population. Moreover, it is now apparent that such dysfunction can be an early sign of neurodegenerative diseases such as Alzheimer's and Parkin-son's. Importantly, older anosmics are three times more likely to die over the course of an ensuring five-year period than their normosmic peers, a situation that may be averted in some cases by appropriate nutritional and safety counseling. This review provides the clinician, as well as the academic and industrial researcher, with an overview of the available means for accurately assessing smell and taste function, including up-to-date information and normative data for advances in this field.展开更多
文摘In accounts of the development and progression of psychophysical disorders such as Hereditary Spastic Paraplegia (HSP) and Facioscapulohumeral Muscular Dystrophy (FSHD), the role of beliefs, perceptions, and behavioral patterns has often been overlooked in favor of a genetically determinist paradigm. This paper explores the impact of NeuroPhysics Treatment (NPT) on patients with HSP and FSHD. Through a series of clinical case reports, I demonstrate how intensive four-day NPT sessions can lead to rapid restoration of lost functions, challenging the conventional view of these disorders. I hypothesize that, by modulating the patient’s perceptual and behavioral frameworks, NPT facilitates the emergence of healthier patterns, suggesting that environmental and psychological factors significantly influence the manifestation and management of these conditions. These findings indicate that the role of genetic inheritance may be overstated and that beliefs and perceptions could play a crucial role in the evolution of psychophysical disorders. The implications of this research extend beyond the traditional treatment paradigms, advocating for a more holistic approach that integrates the psychophysical dimensions of health and challenges the deterministic perspective of genetic inheritance.
文摘The brain is a unique organization in nature, having the psychic activity, which is expressed in subjective states: thoughts, feelings, emotions. Knowledge of the nature of mental activity of the brain is the most urgent and the most challenging task of physiology. Historically the neurophysiology developed on the basis of physical and chemical laws discovered in an inanimate nature. Our investigation is devoted towards the origin of a human subjective state, and presents a new methodology for studying of the nature psychic brain activity. We have established the existence of physical phenomena unique for the living brain so-called “psychogenic field”, which reflects the expressed psychic state of human brain. The subjective state of a human being was shown to affect remotely the physicochemical properties of the blood. An original schematic diagram is presented to describe the formation of the brain psychic activity. This approach is based on the feedback influence of a psychogenic field on neuronal molecular processes (self-induction in the brain). We propose a paradigm for the origin of psychic state and possible existence of the fields, which are unique for the brain. The presented scheme and paradigm of systemic organization of psychic activity of the brain are a prerequisite for the subsequent development of the theory consciousness.
文摘Leakage currents, tiny currents flowing from an everyday-life appliance through the body to the ground, can cause a non-adequate perception （called electrocutaneous sensation, ECS） or even pain and should be avoided. Safety standards for low-frequency range are based on experimental results of current thresholds of electrocutaneous sensations, which however show a wide range between about 50 pA （rms） and 1000 μA （rms）. In order to be able to explain these differences, the perception threshold was measured repeatedly in experiments with test persons under identical experimental setup, but by means of different methods （measuring strategies）, namely： direct adjustment, classical threshold as amperage of 50% perception probability, and confidence rating procedure of signal detection theory. The current is injected using a I cm2 electrode at the highly touch sensitive part of the index fingertip. These investigations show for the first time that the threshold of electrocutaneous sensations is influenced both by adaptation to the non-adequate stimulus and individual, emotional factors. Theretbre, classical methods, on which the majority of the safety investigations are based, cannot be used to determine a leakage current threshold. The confidence rating procedure of the modem signal detection theory yields a value of 179.5 μA （rms） at 50 Hz power supply net frequency as the lower end of the 95% confidence range considering the variance in the investigated group. This value is expected to be free of adaptation influences, and is distinctly lower than the European limits and supports the stricter regulations of Canada and USA.
基金This work was supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(Nos.2019R1F1A1062752 and 2019R1C1C1006539)and was supported by the Soonchunhyang University Research Fund.
文摘This research implements a random dot kinematogram(RDK)using virtual reality(VR)and analyzes the results based on normal subjects.Visual motion perception is one of visual functions localized to a specific cortical area,the human motion perception area(human analogue for the middle temporal/middle superior temporal area)located in the parieto–occipito–temporal junction of the human brain.The RDK measures visual motion perception capabilities.The stimuli in conventional RDK methods are presented using a monitor screen,so these devices require a spacious dark room for installation and use.Recently,VR technology has been implemented in different medical domains.The test method proposed in this study include a VR-based RDK that can independently measure human motion perception abilities without any spatial constraints via a VR head-mounted display.Subsequently,the VR-based RDK was implemented,and the visual perception abilities of the normal subjects were measured based on varying coherences.In both screen-and VR-based RDK tests,the easier the stimulus is,the higher the correct answer rate and the shorter the reaction time.No significant differences in coherence thresholds were observed between the two test methods.The VRbased RDK proposed in this study can be used as a diagnosis tool for visual motion perception and neurodegenerative disorders affecting the posterior region of the brain.
基金Funded by Key Research Project of Liaoning Province Bureau of Science and Technology under the grant No. 2008217004China's Post-Doctoral Science Fund under the grant No. 200704111071
文摘To produce a smoother and more natural interpolated image, and to preserve and enhance original image details, we defined three perception-based local statistic parameters, namely contrast, noise visibility, and edge strength based on three psychophysical principles, including Weber’s Law, Fechner’s Law, and Stevens’ Power Law, and integrated these parameters into a fuzzy logic system to set up an advanced image interpolation algorithm. Application of this algorithm to detect edge behaviors and local statistical information of images demonstrated better noise removal ability and obtained sharper edges than traditional image interpolation algorithems such as nearest neighbor, bilinear and bicubic interpolation methods.
文摘Anomalies in decision over time (e.g., “hyperbolic time discounting”) and under risk (e.g., Allais paradox and hyperbolic probability discounting) have been attracting attention in behavioral and neuroeconomics. We have proposed that psychophysical time commonly explains anomalies in both decisions (Takahashi, 2011, Physica A;Takahashi et al., 2012, J Behav Econ & Finance). By adopting the q-exponential time and probability discounting models, our psychophysical and behavioral economic experiment confirmed that nonlinear distortion of psychophysical time is a common cause of the anomalies in decision both over time and under risk (i.e., intertemporal choice and decision under risk). Implications for psychophysical neuroeconomics and econophysics are discussed.
文摘Mathematical frameworks of quantum theory have recently been adopted in cognitive and behavioral sciences, to explain the violations of normative decision theory and anomalies in cognition. However, to date, no study has attempted to explore neural implementations of such “quantum-like” information processing in the brain. This study demonstrates that neural population coding of information with nonlinear neural response functions can account for such “quantum” information processing in decision-making and cognition. It is also shown that quantum decision theory is a special case of more general population vector cording theory. Future applications of the present theory in the rapidly evolving field of “psychophysical neuroeconomics” are also discussed.
文摘We developed a psychophysical paradigm for the clinical assessment of the contrast sensitivity (CS) mediated by the ON- and OFF-systems of the Magnocellular and Parvocellular pathways. We designed a stimulus considering two dimensions: two spatial frequencies (0.5 and 4.5 cpd) and two temporal rates of flicker (33 ms and 1500 ms). To evidence the ON- and OFF responses, the CS was measured for two polarities of light with luminance changes of 0.6 dB steps above and below the medium luminance grey background. We tested 38 healthy volunteers. The results shows that Magnocellular contrast sensitivity was higher than Parvocellular for the 33 ms flickering stimulus and the Parvocellular contrast sensitivity was higher than Magnocellular for 1500 ms stimuli. The reliability of the test was checked and confirmed. We concluded that the test performs a rapid measurement of the CS mediated by the ON and OFF systems of Magnocellular and Parvocellular pathways. It is useful in clinical protocols due to its high sensitivity and good reliability.
文摘Nowadays, there is a great need to investigate the effects of fatigue on physical as well as mental performance. The issues that are generally associated with extreme fatigue are that one can easily lose one’s focus while performing any particular activity whether it is physical or mental and this decreases one’s motivation to complete the task at hand efficiently and successfully. In the same line of thought, myriads of research studies posited the negative effects of fatigue on mental performance, and most techniques to induce fatigue to require normally long-time and repetitive visual search tasks. In this study, a visual search algorithm task was devised and customized using performance measures such as <em>d</em>’ (<strong>d-prime</strong>) and Speed Accuracy Trade-Off (<strong>SATF</strong>) as well as <strong>ROC</strong> analysis for classifier performance. The visual search algorithm consisted of distractors (<strong>L</strong>) and a target (<strong>T</strong>) whereby human participants had to press the appropriate keyboard button as fast as possible if they notice a target or not upon presentation of a visual stimulus. It was administered to human participants under laboratory conditions, and the reaction times, as well as accuracy of the participants, were monitored. It was found that the test image Size35Int255 was the best image to be used in terms of sensitivity and AUC (Area under Curve). Therefore, ongoing researches can use these findings to create their visual stimuli in such a way that the target and distractor images follow the size and intensity characteristics as found in this research.
文摘Background:Stereoscopic Vision uses the disparity between the two images received by the two eyes in order to create a tridimensional representation.With this study,we aimed at providing an estimate of binocular vision at a level prior to disparity processing.In particular,we wanted to assess the spatial properties of the visual system for detecting interocular correlations(IOC).Methods:We developed dichoptic stimuli,made of textures which IOC is sinusoidally modulated at various correlation spatial frequencies.Then,we compared the sensitivity to these stimuli to the sensitivity to analogous stimuli with disparity modulation.Results:We observed that IOC sensitivity presents a low-pass/band-pass profile and increases as a function of presentation duration and contrast,in a similar way as disparity sensitivity.Conclusions:IOC sensitivity is weakly-though significantly-correlated with disparity sensitivity in the general population,which suggests that it could provide a marker for binocular vision,prior to disparity processing.
文摘Background:The human visual system can use binocular disparity to make depth judgements.Previous studies looking at the normal population have found a wide range in ability to perform depth-polarity tasks.We explored if these large individual differences are also present when using a depth increment paradigm,and if they depend on the sign of disparity.Methods:Stereoacuity for detecting a wedge-shaped surface in a field of dots was measured in 53 adults(28 males)with normal vision.To better understand the variance in stereoacuity in the sample,for 18 subjects we measured stereo cuity with disparity noise added to the stimulus.Stereoacuity was unaffected at low levels of stimulus noise but beyond a critical value,it increased with the standard deviation of the noise.At this point the stimulus noise is equivalent to the internal noise of the subject.Stereoacuity measured at high stimulus noise levels reflects the efficiency with which a noisy input is processed by the visual system.We derived both parameters by fitting the linear amplifier model.Results:Stereoacuity ranged from 24 to 275 arc seconds.We found population differences in stereoacuity were explained by variation in both processing efficiency and internal noise levels.There was a tendency for higher task performance for crossed disparities compared to uncrossed disparities.Within subject sensitivity differences between crossed and uncrossed disparity were due to a higher efficiency when processing one direction.There was a trend for subjects with equal acuity for the two directions to have an increase in processing efficiency compensating for higher internal noise levels for that direction.Conclusions:Overall,our results show that the individual differences in stereoacuity for depth increment tasks can be attributed to variances in both the quality of the received input and the efficiency of processing of disparity-processing mechanisms.
文摘The polar surface area of a molecule is currently defined as the surface sum over all polar atoms, primarily oxygen and nitrogen, also including their attached hydrogens (named PSA1 in the present study). Some authors also include sulfur and phosphor (PSA3). The slight modification suggested here is based on the fact that it is difficult to consider, on a theoretical point of view, hexavalent S and pentavalents N and P as polar atoms. Indeed, in these cases, all their peripheral electrons are involved in bondings. We propose to define PSA2 using the initial definition extended to O, S, N, P, with the exception of hexavalent S and pentavalents N and P. In order to test this hypothesis, the three expressions PSA1, PSA2 and PSA3 have been applied in a QSAR to a physiological phenomenon called comfort olfactory perceived intensity, for the human responses to 186 odorants (QSAR stands for Quantitative Structure Activity Relationship). The PSA2 expression has been selected as the more suitable, associated with two other molecular properties (molar refraction and Van der Waals molecular volume).
文摘Stochastic resonance phenomenon in the biological sensory systems has been studied through the signal detection theories and the psychophysical experiments. In this paper, sensory systems are considered as a threshold detector including the receiver part and the classifier part. Compared with conventional models regarding the receiver part of sensory system as a linear or single non-linear system, a summing network was constructed by MacCulloch-Pitts neurons to simulate the receiver part. The simulation results show that the relevant index of the detectability of signal exhibit the stochastic resonance behaviours. The psychophysical experiments were carried out through the 2IFC (two interval two alternative forced choice) method. The experimental results qualitatively verify the conclusion in accordance with the theoretical model. These works give a proof that stochastic resonance is not only epiphenonmenon in sensory systems.
基金supported by National Key Research and Development Program of China(2017YFC0822204)National Natural Science Foundation of China(NSFC)(51935010)+1 种基金Beijing Municipal Natural Science Foundation(LI92001)Tsing-hua University Initiative Scientific Research Program(20197010009).
文摘Lack of temperature sensation of myoelectric prosthetic hand limits the daily activities of amputees.To this end,a noninvasive temperature sensation method is proposed to train amputees to sense temperature with psychophysical sensory substitution.In this study,22 healthy participants took part besides 5 amputee participants.The duration time of the study was 31 days with five test steps according to the Leitner technique.An adjustable temperature mug and a Peltier were used to change the temperature of the water/phantom digits to induce temperature to participants.Also,to isolate the surroundings and show colors,a Virtual Reality(VR)glass was employed.The statistical results conducted are based on the response of participants with questionnaire method.Using Chi-square tests,it is concluded that participants answer the experiment significantly correctly using the Leitner technique(P value<0.05).Also,by applying the“Repeated Measures ANOVA”,it is noticed that the time of numbness felt by participants had significant(P value<0.001)difference.Participants could remember lowest and highest temperatures significantly better than other temperatures(P value<0.001);furthermore,the well-trained amputee participant practically using the prosthesis with 72.58%could identify object’s temperature with only once time experimenting the color temperature.
文摘The study aims to highlight the contribution of sport as a tool for preventing early school leaving and developing psychophysical well-being.School,territory and sports association can,with appropriate institutional partnership actions,implement training interventions in this sense.Through an analysis of the scientific literature we want to highlight the important value of sports practice especially in school age.Organized sports activities contribute to the development of skills related to socio-relational well-being.Full awareness of one’s own cognitive and social skills allows improving self-perception.Sport,therefore,becomes a tool for preventing and contrasting early school leaving,a real protective factor that limits the decrease in motivation to school attendance and favors school performance.
文摘<strong>Background:</strong> Nurses are very important frontline health care professionals as they spend more time with patients than other professionals. This is even more so at this critical time of the COVID-19 pandemic. The nursing profession is facing great challenges in coping with the pandemic as they are more vulnerable to exposure and infection with the disease. Kuwait is not spared from the global pandemic which has put the health sector under immense pressure. Because COVID-19 is highly transmissible and deadly, it poses a huge health risk to nurses and has a huge impact on their cognitive, emotional, behavioural and physical dimensions. <strong>Aim:</strong> The study aims to explore the positive and negative emotions and feelings of staff nurses while giving care to COVID-19 patients. <strong>Materials and Methods:</strong> A descriptive cross-sectional study was carried out. 300 nurses from different general hospitals, field hospitals, and quarantine facilities in Kuwait participated in the study. A questionnaire was used to collect the data. <strong>Results:</strong> The findings show that for the cognitive evaluation, 72% were moderately affected, for the emotional evaluation 51.3% and 44% were moderately and mildly affected respectively, for the behavioural evaluation, 66.7% were severely affected, and for the physical evaluation, 43.3% and 31.7% were moderately and severely affected respectively. Prolonged working hours has a highly significant negative correlation to emotional (<em>r</em> <span style="white-space:nowrap;">−</span>0.165), behavioral (<em>r</em> <span style="white-space:nowrap;">−</span>0.177) and physical (<em>r</em> <span style="white-space:nowrap;">−</span>0.155) dimension of the nurses at 0.01 level using Spearman’s correlation. <strong>Conclusion:</strong> The study concluded that the COVID-19 pandemic has affected the psychophysical dimensions of staff nurses.
文摘We consider the psychophysical experiments in which the test subject’s binary reaction is determined by the prescribed exposure duration to a stimulus and a random variable subjective threshold. For example, when a subject is exposed to a millimeter wave beam for a prescribed duration, the occurrence of flight action is binary (yes or no). In experiments, in addition to the binary outcome, the actuation time of flight action is also recorded if it occurs;the delay from the initiation time to the actuation time of flight action is the human reaction time, which is not measurable. In this study, we model the random subjective threshold as a Weibull distribution and formulate an inference method for estimating the human reaction time, from data of prescribed exposure durations, binary outcomes and actuation times of flight action collected in a sequence of tests. Numerical simulations demonstrate that the inference of human reaction time based on the Weibull distribution converges to the correct value even when the underlying true model deviates from the inference model. This robustness of the inference method makes it applicable to real experimental data where the underlying true model is unknown.
基金supported by the National Natural Science Foundation of China (Grant Nos. 31971031, 31930053, and 32171039)the STI2030Major Projects (Grant Nos. 2021ZD0203600, 2022ZD0204802, and 2022ZD0204804)。
文摘The visual system continuously adapts to the statistical properties of the environment. Existing evidence shows a close resemblance between deep convolutional neural networks(CNNs) and primate visual stream in neural selectivity to naturalistic textures above the primary visual processing stage. This study delves into the mechanisms of perceptual learning in CNNs,focusing on how they assimilate the high-order statistics of natural textures. Our results show that a CNN model achieves a similar performance improvement as humans, as manifested in the learning pattern across different types of high-order image statistics. While L2 was the first stage exhibiting texture selectivity, we found that stages beyond L2 were critically involved in learning. The significant contribution of L4 to learning was manifested both in the modulations of texture-selective responses and in the consequences of training with frozen connection weights. Our findings highlight learning-dependent plasticity in the mid-to-high-level areas of the visual hierarchy. This research introduces an AI-inspired approach for studying learning-induced cortical plasticity, utilizing DCNNs as an experimental framework to formulate testable predictions for empirical brain studies.
基金the National Natural Science Foundation of China (Grant Nos. 39893340-06, 69835020 & 39670186).
文摘In the information processing procedure of stereo vision, theuniqueness constraint has been used as one of the constraints to solve the "correspondence problem". While the uniqueness constraint is valid in most cases, whether it is still valid in some particular stimulus configuration (such as Panum's limiting case) has been a problem of widespread debate for a long time. To investigate the problem, we adopted the Panum's limiting case as its basic stimulus configuration, and delved into the phenomenon of binocular fusion from two distinct aspects: visual direction and orientation disparity. The results show that in Panum's limiting case binocular fusion does not comply with the rules governing regular binocular fusion as far as visual direction and orientation disparity are concerned. This indicates that double fusion does not happen in Panum's limiting case and that the uniqueness constraint is still valid.
文摘Although hundreds of thousands of patients seek medical help annually for disor-ders of taste and smell, relatively few medical practitioners quantitatively test their patients' chemosensory function, taking their complaints at face value. This is clearly not the approach paid to patients complaining of visual, hearing, or balance problems. Accurate chemosensory testing is essential to establish the nature, degree, and veracity of a patient's complaint, as well as to aid in counseling and in monitoring the effectiveness of treatment strategies and de-cisions. In many cases, patients perseverate on chemosensory loss that objective assessment demonstrates has resolved. In other cases, patients are malingering. Olfactory testing is crit-ical for not only establishing the validity and degree of the chemosensory dysfunction, but for helping patients place their dysfunction into perspective relative to the function of their peer group. It is well established, for example, that olfactory dysfunction is the rule, rather than the exception, in members of the older population. Moreover, it is now apparent that such dysfunction can be an early sign of neurodegenerative diseases such as Alzheimer's and Parkin-son's. Importantly, older anosmics are three times more likely to die over the course of an ensuring five-year period than their normosmic peers, a situation that may be averted in some cases by appropriate nutritional and safety counseling. This review provides the clinician, as well as the academic and industrial researcher, with an overview of the available means for accurately assessing smell and taste function, including up-to-date information and normative data for advances in this field.
