To extract the temporal structure of sensory inputs is of great significance to our adaptive functioning in the dynamic environment. Here we characterize three types of temporal structure information, and review behavioral and neural evidence bearing on the encoding and utilization of such information in visual and auditory perception. The evidence together supports a functional view that the brain not only tracks but also makes use of temporal structure from diverse sources for a broad range of cognitive processes, such as perception, attention, and unconscious information processing. These functions are implemented by brain mechanisms including neural entrainment, predictive coding, as well as more specific mechanisms that vary with the type of temporal regularity and sensory modality. This framework enriches our understanding of how the human brain promotes dynamic information processing by exploiting regularities in ubiquitous temporal structures.
Attention ; Auditory Perception ; Brain ; physiology ; Humans ; Time Perception ; Visual Perception

Time is an important element for cognitive processes. Timing and time perception have been investigated by neuroscientists and psychologists for many years. It is well accepted that emotions could alter our experience of time. Previous studies of the emotional modulation on temporal perception focus primarily on behavioral and psychological experiments. In recent years, studies about the neurophysiological mechanisms of time perception have made some progress. Therefore, researchers started to explore how emotions influence our sense of time on the aspects of neural networks, neurotransmitters and synaptic plasticity. In this paper, we tried to review current studies about the effects of emotional regulation on time perception and the relevant neurophysiological mechanisms. This review will help us to deeply understand the neural mechanisms of time perception.
Emotions ; Neuronal Plasticity ; Time Perception

The saccadic reaction times to the double-step stimuli were studied in three human subjects to ascertain the saccadic visual tracking characteristics. Responses to simple step and double-step target motions were measured where the target mode and stimulus durations were randomized. To measure the eye movement the Photo-electric Eye Monitor was constructed based on limbus tracking. The results indicate that observers represented two kind of responses (A-or B-type) depending upon the stimulus duration. The percentage of occurrances increased as the stimulus duration increased from 50 to 200 msec. When the subject responded to both target motions, the reaction time of the second saccade was shorter than that of the first. The successive visual information is to change continuously the reaction time or cancel the initial saccade. Our results revealed that parallel data processing characteristics of the visual tracking systems and the saccadic decision-makings are influenced by the temporal relationships.
Adult ; Eye Movements* ; Human ; Male ; Motion Perception* ; Reaction Time* ; Saccades* ; Visual Perception*

From neurophenomenological perspectives, schizophrenia has been conceptualized as "a disorder with heterogeneous manifestations that can be integrally understood to involve fundamental perturbations in consciousness". While these theoretical constructs based on consciousness facilitate understanding the 'gestalt' of schizophrenia, systematic research to unravel translational implications of these models is warranted. To address this, one needs to begin with exploration of plausible biological underpinnings of "perturbed consciousness" in schizophrenia. In this context, an attractive proposition to understand the biology of consciousness is "the orchestrated object reduction (Orch-OR) theory" which invokes quantum processes in the microtubules of neurons. The Orch-OR model is particularly important for understanding schizophrenia especially due to the shared 'scaffold' of microtubules. The initial sections of this review focus on the compelling evidence to support the view that "schizophrenia is a disorder of consciousness" through critical summary of the studies that have demonstrated self-abnormalities, aberrant time perception as well as dysfunctional intentional binding in this disorder. Subsequently, these findings are linked with 'Orch-OR theory' through the research evidence for aberrant neural oscillations as well as microtubule abnormalities observed in schizophrenia. Further sections emphasize the applicability and translational implications of Orch-OR theory in the context of schizophrenia and elucidate the relevance of quantum biology to understand the origins of this puzzling disorder as "fundamental disturbances in consciousness".
Biology ; Consciousness* ; Microtubules ; Neurons ; Quantum Theory* ; Schizophrenia* ; Time Perception

OBJECTIVES: Children with attention-deficit hyperactivity disorder (ADHD) may have deficits in time perception, as assessed by the time estimation task and the time reproduction task, however its age-related trajectory is not yet determined. Therefore we examined the correlation between accuracy of time perception tasks and age, and the association between accuracy of estimation tasks and reproduction tasks. METHODS: Sixty-three patients with ADHD, aged 8 to 18 years tested the tasks for five time durations (2, 4, 12, 45, and 60 seconds). Accuracy of tasks was assumed differences (absolute values) between raw results of tasks and original time durations. Spearman's correlation analysis was performed to determine correlation between accuracy of time perception tasks and age. Multivariate regression was used to determine the association of accuracy of estimation tasks with accuracy of reproduction tasks. RESULTS: Age showed correlation with accuracy of estimation tasks, but not with that of reproduction tasks. We observed that the higher the accuracy in 12, 45, and 60 seconds duration time reproduction, the higher the accuracy in longer seconds duration time estimation. CONCLUSION: Age was correlated with time estimation accuracy whereas there was no impact on time reproduction accuracy. Association of each of the two time perception tasks, particularly in longer time duration, suggested specific impairments in time perception.
Adolescent* ; Age Factors ; Child* ; Humans ; Reproduction ; Time Perception*

Objective. This study aims to determine time and motion in the operating room in emergent, urgent and scheduled cesarean section surgeries among pregnant COVID-19 patients. Methodology. A time and motion performance evaluation study was done by computing the following parameters: pre-induction time, pre-incision time, opening time, closing time, for both decision-to-delivery interval (DDI) and overall operative time. Results. During the study period, emergent DDI average was 2 hours and 38 minutes, emergent overall operative time was 1 hour and 31 minutes, urgent DDI average was 3 hours and 51 minutes, and urgent overall operative time of 1 hour and 57 minutes. However, in both urgent and emergent cases, the recommended DDI of 30 minutes, and the average duration of 44.3 minutes for CS were not feasible. Conclusion. The COVID-19 pandemic has negatively affected the provision of surgical obstetric care and OR utilization. Due to the new safety protocol for healthcare workers and patients, there was a significant delay in DDI and overall operative time. The causes were preparation, anesthesia factors or obstetrician factors. Identifying modifiable obstacles may improve the DDI, overall operative time, and the quality of maternal and child birth care during this pandemic.
Pregnancy ; Female ; Cesarean Section ; Time and Motion Studies ; COVID-19 ; Time Perception ; Motion

Many patients complain of near vision difficulty after PRK surgery. In the prospective study, we report the effect of PRK surgery for myopia on accommodation and binocular vision. 45 myopic eyes (39 patients, 9 males, 30 females) underwent PRK for myopia. Mean preoperative amplitude of accommodation in moderate degree myopia (group 1 < OR = -6.00D in shperical equivalent : range -2.45 ~ -6.00D) was 7.01+/-1.25D, mean preoperative amplitude of accommodation in high degree myopia (group 2 > -6.00D in spherical equivalent : range -6.10 ~ -10.75D) was 6.85+/-1.41D. Mean postoperative amplitude of accommodation of group 1 was 8.13+/-1.38D, mean postoperative amplitude of accommodation of group 2 was 7.80+/-1.33D, the difference of both groups were statistically significant(p>0.05). Mean preoperative amplitude of accommodation of all patients was 6.91+/-1.35D, mean postoperative amplitude of accommodation was 7.93+/-1.36D, the difference are statistically significant (p>0.01). 12 of 39 patients complained of near vision difficulty while reading after PRK surgery on their one eye, but 3 of them who underwent PRK surgery on their the other eye noticed the disappearance of near vision difficulty. Stereopsis was tested and 15 of 36 patient lost more than 50 sec/arc of streoacuity. Near vision difficulty was not related to the amount of myopia corrected, not related to the stereoacuity change but seemed to related to their adaptability or their reaction time of accommodation with their operated eyes.
Depth Perception ; Humans ; Lasers, Excimer* ; Male ; Myopia ; Photorefractive Keratectomy* ; Prospective Studies ; Reaction Time ; Telescopes* ; Vision, Binocular*

OBJECTIVE: To investigate the hemispheric contributions to prosody recognitions and interference effects of semantic processing on prosody for stroke patients by using the Korean language. METHODS: Ten right hemisphere damaged patients (RHD), nine left hemisphere damaged patients (LHD), and eleven healthy controls (HC) participated. In pure prosody recognition task, four semantically neutral sentences were selected and presented in both sad and happy prosodies. In interference task, participants listened to emotionally intoned sentences in which the semantic contents were congruent or incongruent with prosody. Participants were asked to rate the valence of prosody while ignoring the semantic contents, and thus, reaction time and accuracy were estimated. RESULTS: In pure prosody recognition task, RHD showed low accuracy as compared to HC (p=0.013), and the tendency of group response showed that RHD performed worse than HC and LHD with regards to accuracy and reaction time. In interference task, analysis of accuracy revealed a significant main effect of groups (p=0.04), and the tendency implied that RHD is less accurate as compared to LHD and HC. The RHD took longer reaction times than HC in congruent and incongruent items (p<0.001). CONCLUSION: Right hemispheric laterality to prosody processing of Korean language in stroke patients was observed. Interference effects of semantic contents to prosody processing were not observed, which suggested unique characteristics of prosody for Korean language. These results could be referred as preliminary data for future researches on Korean languages.
Functional Laterality ; Humans ; Reaction Time ; Semantics ; Speech Disorders ; Speech Perception ; Stroke*

PURPOSE: This study aimed to quantify the shift of colorimetric values in the Ishihara pseudoisochromatic test with aging of the plates. METHODS: Three sets of Ishihara pseudoisochromatic plates with different published dates (printed in 1971, 1983 and 2001) were tested. Positions matching 32 dots with 13 colors were chosen from each set and the colorimetric values with the CIELAB and HSB/HLS color systems were measured with a spectrophotometer. Lightness (L*), red-green (a*), blue-yellow (b*), chroma, red hue, yellow hue, and green hue values from each set were compared. RESULTS: L* and chroma values were significantly higher in the older versions. The a* values shifted to red (increased a*) and the b* values shifted to yellow (increased b*) with plate aging. CONCLUSIONS: Our results showed that the pseudoisochromatic plates had significant changes in color values and a directional shift with aging.
Color ; *Color Perception ; Color Vision Defects/*diagnosis ; *Colorimetry ; Humans ; Spectrophotometry ; Time Factors ; Vision Tests/*instrumentation

Human studies of brain stimulation have demonstrated modulatory effects on the perception of pain. However, whether the primary somatosensory cortical activity is associated with antinociceptive responses remains unknown. Therefore, we examined the antinociceptive effects of neuronal activity evoked by optogenetic stimulation of primary somatosensory cortex. Optogenetic transgenic mice were subjected to continuous or pulse-train optogenetic stimulation of the primary somatosensory cortex at frequencies of 15, 30, and 40 Hz, during a tail clip test. Reaction time was measured using a digital high-speed video camera. Pulse-train optogenetic stimulation of primary somatosensory cortex showed a delayed pain response with respect to a tail clip, whereas no significant change in reaction time was observed with continuous stimulation. In response to the pulse-train stimulation, video monitoring and local field potential recording revealed associated paw movement and sensorimotor rhythms, respectively. Our results show that optogenetic stimulation of primary somatosensory cortex at beta and gamma frequencies blocks transmission of pain signals in tail clip test.
Animals ; Brain ; Humans ; Mice ; Mice, Transgenic ; Neurons ; Optogenetics ; Pain Perception* ; Reaction Time ; Somatosensory Cortex* ; Tail*