A perceptual glitch in serial perception generates temporal distortions

Precisely estimating event timing is essential for survival, yet temporal distortions are ubiquitous in our daily sensory experience. Here, we tested whether the relative position, duration, and distance in time of two sequentially-organized events—standard S, with constant duration, and comparison C, with duration varying trial-by-trial—are causal factors in generating temporal distortions. We found that temporal distortions emerge when the first event is shorter than the second event. Importantly, a significant interaction suggests that a longer inter-stimulus interval (ISI) helps to counteract such serial distortion effect only when the constant S is in the first position, but not if the unpredictable C is in the first position. These results imply the existence of a perceptual bias in perceiving ordered event durations, mechanistically contributing to distortion in time perception. We simulated our behavioral results with a Bayesian model and replicated the finding that participants disproportionately expand first-position dynamic (unpredictable) short events. Our results clarify the mechanisms generating time distortions by identifying a hitherto unknown duration-dependent encoding inefficiency in human serial temporal perception, something akin to a strong prior that can be overridden for highly predictable sensory events but unfolds for unpredictable ones

Assessment of Clinical Outcome Based on Womac Score Between Intra-Articular Injection of Platelet Rich Plasma and Long Acting Corticosteriod in Stage Ii-Iii Kelgren-Lawrence Osteoarthritis of Knee

Introduction: Osteoarthritis is chronic degenerative condition of joint characterized by progressive deterioration of cartilage and inflammation, causing pain and limiting functional of joints. Intra-articular corticosteroid injections are most commonly used to reduce the symptoms in Osteoarthritis, but their effects are often last for short-term and may come with risks factors. Platelet-rich plasma (PRP), an autologous treatment, has evolved into a potential alternative method to improve the limitation of joint function that may provide more sustainable relief. Objective: This study is to determine clinical outcomes of intra-articular injections of platelet-rich plasma and steroids for the treatment of knee osteoarthritis over a period of 6 months follow-up. The focus of this study is to measuring the extent of pain relief and functional improvement. Methods: A prospective randomized control study was conducted in 50 patients diagnosed with Grade II and III knee OA. Patients  allocated randomly into two groups: Group A (corticosteroid injection) and Group B (PRP injection). All the patients had undergone a  Clinical examination and then outcome were assessed using Visual Analogue Scale (VAS) for pain and Western Ontario and McMaster Universities Arthritis Index (WOMAC) for function at baseline, 1, 3, and 6 months. Results: Both modality of treatment showed improvements in pain and function, with PRP showed a better reduction of VAS and WOMAC scores. At end of 6 months, VAS score in Group A decreased by 2.5 points, while Group B showed reduction of only 4.2-point. WOMAC total scores in Group B improved more significantly reduction in  pain, stiffness, and function improvement compared to Group A. Conclusion: In our study both corticosteroid and platelet rich plasma showed significant reduction in pain and improving function of  KL grade II & III osteoarthritis knee. Intra-articular PRP injection showed significant short-term similar reduction of pain but knee function with no significant difference when compared to corticosteroids therapy at end of follow-up. However, PRP treatment resulted in a longer sustained effect. Intra-articular PRP injection is safe, it can reduce pain, and it can improve knee function of patients with mild/moderate knee OA for longer period. DOI: https://doi.org/10.52783/jchr.v14.i6.687

The fundamental frequencies of our own voice

Own actions send a corollary discharge (CD) signal, that is a copy of the planned motor programme, to sensory-specific brain areas to suppress the anticipated sensory response, providing a neural basis for the sense of self. When we speak, the sensory consequences of the fundamental frequency (f0) of our own voice, generated by vocal fold vibrations, are suppressed. However, due to bone/air conduction filtering effects, the f0 we self-generate is measurably different from the f0 we subjectively perceive as defining our own voice. Using an auditory change deafness paradigm, we parametrically tested the sensitivity to auditory change in the frequency neighbourhoods of objective and subjective own voice pitches and found that participants experience change deafness for both to a similar extent, relative to a control pitch condition. We conclude that when we listen attentively, we are likely to filter out small pitch changes in the vicinity of our own objective and subjective voice f0, possibly as a long-term consequence of speaking-induced suppression mechanisms integrated with individual, perceptual bodily priors

Gesture's body orientation modulates the N400 for visual sentences primed by gestures

Body orientation of gesture entails social‐communicative intention, and may thus influence how gestures are perceived and comprehended together with auditory speech during face‐to‐face communication. To date, despite the emergence of neuroscientific literature on the role of body orientation on hand action perception, limited studies have directly investigated the role of body orientation in the interaction between gesture and language. To address this research question, we carried out an electroencephalography (EEG) experiment presenting to participants (n = 21) videos of frontal and lateral communicative hand gestures of 5 s (e.g., raising a hand), followed by visually presented sentences that are either congruent or incongruent with the gesture (e.g., “the mountain is high/low…”). Participants underwent a semantic probe task, judging whether a target word is related or unrelated to the gesture‐sentence event. EEG results suggest that, during the perception phase of handgestures, while both frontal and lateral gestures elicited a power decrease in both the alpha (8–12 Hz) and the beta (16–24 Hz) bands, lateral versus frontal gestures elicited reduced power decrease in the beta band, source‐located to the medial prefrontal cortex. For sentence comprehension, at the critical word whose meaning is congruent/incongruent with the gesture prime, frontal gestures elicited an N400 effect for gesture‐sentence incongruency. More importantly, this incongruency effect was significantly reduced for lateral gestures. These findings suggest that body orientation plays an important role in gesture perception, and that its inferred social‐communicative intention may influence gesture‐language interaction at semantic level

Full throttle:Demonstrating the speed, accuracy, and validity of a new method for continuous two-dimensional self-report and annotation

Research on fine-grained dynamic psychological processes has increasingly come to rely on continuous self-report measures. Recent studies have extended continuous self-report methods to simultaneously collecting ratings on two dimensions of an experience. For all the variety of approaches, several limitations are inherent to most of them. First, current methods are primarily suited for bipolar, as opposed to unipolar, constructs. Second, respondents report on two dimensions using one hand, which may produce method driven error, including spurious relationships between the two dimensions. Third, two-dimensional reports have primarily been validated for consistency between reporters, rather than the predictive validity of idiosyncratic responses. In a series of tasks, the study reported here addressed these limitations by comparing a previously used method to a newly developed two-handed method, and by explicitly testing the validity of continuous two-dimensional responses. Results show that our new method is easier to use, faster, more accurate, with reduced method-driven dependence between the two dimensions, and preferred by participants. The validity of two-dimensional responding was also demonstrated in comparison to one-dimensional reporting, and in relation to post hoc ratings. Together, these findings suggest that our two-handed method for two-dimensional continuous ratings is a powerful and reliable tool for future research

A perceptual glitch in serial perception generates temporal distortions

Precisely estimating event timing is essential for survival, yet temporal distortions are ubiquitous in our daily sensory experience. Here, we tested whether the relative position, duration, and distance in time of two sequentially-organized events—standard S, with constant duration, and comparison C, with duration varying trial-by-trial—are causal factors in generating temporal distortions. We found that temporal distortions emerge when the first event is shorter than the second event. Importantly, a significant interaction suggests that a longer inter-stimulus interval (ISI) helps to counteract such serial distortion effect only when the constant S is in the first position, but not if the unpredictable C is in the first position. These results imply the existence of a perceptual bias in perceiving ordered event durations, mechanistically contributing to distortion in time perception. We simulated our behavioral results with a Bayesian model and replicated the finding that participants disproportionately expand first-position dynamic (unpredictable) short events. Our results clarify the mechanisms generating time distortions by identifying a hitherto unknown duration-dependent encoding inefficiency in human serial temporal perception, something akin to a strong prior that can be overridden for highly predictable sensory events but unfolds for unpredictable ones