Differences In Reaction Time Research Articles

Selective stimulation of nociceptive small fibers during intraepidermal electrical stimulation: Experiment and computational analysis.

Electrical stimulation of skin nociceptors is gaining attention in pain research and peripheral neuropathy diagnosis. However, the optimal parameters for selective stimulation are still difficult to determine because they require simultaneous characterization of the electrical response of small fibers (Aδ- and C-fibers). In this study, we measured the in vivo electrical threshold responses of small fibers to train-pulse stimulation in humans for the first time. We also examined selective stimulation via a computational model, which combines electrical analysis, and terminal fiber and synaptic models, including the first cutaneous pain C-fiber model. Selective stimulation of small fibers is performed by injecting train-pulse stimulation via coaxial electrodes with an intraepidermal needle tip at varying pulse counts and frequencies. The activation Aδ- or C-fibers was discriminated from the differences in reaction time. Aδ-fiber elicited a pinpricking sensation with a mean reaction time of 0.522 s, and C-fiber elicited a tingling sensation or slight burning itch with a mean reaction time of 1.243 s. The implemented multiscale electrical model investigates synaptic effects while considering stimulation waveform characteristics. Experimental results showed that perception thresholds decreased with the number of consecutive pulses and frequency up to convergence (five pulses or 70 Hz) during the selective stimulation of Aδ- and C-fibers. Considering the synaptic properties, the optimal stimulus conditions for selective stimulation of Aδ- vs. C-fibers were train of at least four pulses and a frequency of 40-70 Hz at a pulse width of 1 ms. The experimental results were modeled with high fidelity by incorporating temporal synaptic effects into the computational model. Numerical analysis revealed terminal axon thickness to be the most important biophysical factor affecting threshold variability. The computational model can be used to estimate perception thresholds while understanding the mechanisms underlying the selective stimulation of small fibers. The parameters derived here are important in exploring selective stimulation between Aδ- and C-fibers for diagnosing neuropathies.

Staggered Onsets of Processing Relevant and Irrelevant Stimulus Features Produce Different Dynamics of Congruency Effects.

The dynamics of congruency effects in conflict tasks can be analyzed by means of delta plots which depict the reaction-time differences between incongruent and congruent conditions across the quantiles of the reaction-time distributions. Delta plots exhibit a variety of different shapes. Here we test the hypothesis that staggered onsets of processing task-relevant and task-irrelevant features for response selection (together with a declining influence of the irrelevant feature) produce such variety. For this purpose, staggered onsets were implemented in two extensions of the Leaky, Competing Accumulator model. We show the cardinal capability of these models to produce different shapes of delta plots with different assumptions about temporal offsets between processing relevant and irrelevant stimulus features. Applying the models to experimental data, we first show that they can reproduce the delta plots observed with a conflict task with stimulus size as the irrelevant feature. For this task congruency effects are delayed and appear only at longer reaction times. Second, we fit the models to the results of two new Simon-task experiments with an experimentally controlled temporal offset in addition to the internal one. The experimentally induced variations of the shape of delta plots for this task could be reasonably well fitted by one of the two models that assumed an early start of response selection as soon as either the relevant or the irrelevant stimulus feature becomes available. We conclude that delta plots are crucially shaped by staggered onsets of processing relevant and irrelevant features for response selection.

Validation of a surgical drill with a haptic interface in spine surgery

Real haptics is a technology that reproduces the sense of force and touch by transmitting contact information with real objects by converting human movements and the feel of the objects into data. In recent years, real haptics technology has been installed in several surgical devices. A custom-made surgical drill was used to drill into the posterior lamina to verify the time required for penetration detection and the distance the drill advanced after penetration. A surgeon operated with the drill and the same aspects were measured and verified. All experiments were performed on female miniature pigs at 9 months of age with a mean body weight of 23.6 kg (range 9–10 months and 22.5–25.8 kg, n = 12). There were statistically significant differences in the average reaction time and the distance travelled after penetration between a handheld drill and the drill with the penetration detection function (p < 0.001). The reaction time to detect penetration and the distance after penetration were both significantly improved when compared with those of the handheld surgical drill without the penetration detection function, with mean differences of 0.049 ± 0.019 s [95% CI 0.012, 0.086 s] and 2.511 ± 0.537 mm [95% CI 1.505, 3.516 mm]. In this study, we successfully conducted a performance evaluation test of a custom-made haptic interface surgical drill. A prototype high-speed drill with a haptic interface accurately detected the penetration of the porcine posterior lamina.

Reliability of attention bias and attention bias variability to climate change images in the dot-probe task.

Climate change is one of the most pressing issues of the 21st century, which is perhaps why information about climate change has been found to capture observers' attention. One of the most common ways of assessing individual differences in attentional processing of climate change information is through the use of reaction time difference scores. However, reaction time-based difference scores have come under scrutiny for their low reliability. Given that a primary goal of the field is to link individual differences in attention processing to participant variables (e.g., environmental attitudes), we assessed the reliability of reaction time-based measures of attention processing of climate change information utilizing an existing dataset with three variations of the dot-probe task. Across all three samples, difference score-based measures of attentional bias were generally uncorrelated across task blocks (r = -0.25 to 0.31). We also assessed the reliability of newer attention bias variability measures that are thought to capture dynamic shifts in attention toward and away from salient information. Although these measures were initially found to be correlated across task blocks (r = 0.17-0.67), they also tended to be highly correlated with general reaction time variability (r = 0.49-0.83). When controlling for general reaction time variability, the correlations across task blocks for attention bias variability were much weaker and generally nonsignificant (r = -0.25 to 0.33). Furthermore, these measures were unrelated to pro-environmental disposition indicating poor predictive validity. In short, reaction time-based measures of attentional processing (including difference score and variability-based approaches) have unacceptably low levels of reliability and are therefore unsuitable for capturing individual differences in attentional bias to climate change information.

Examining long-term repetition priming effects in spoken word recognition using computer mouse tracking.

Language researchers in a variety of disciplines have used priming as a tool to investigate theoretical questions. In spoken word recognition, long-term repetition priming effects have been obtained across a number of behavioral tasks (e.g., lexical decision, shadowing). Repeated - primed - words are responded to more efficiently than new - unprimed - words. However, to our knowledge, long-term repetition priming effects have not been examined using computer mouse tracking, which would provide data regarding the time course of long-term repetition priming effects. Consequently, we compared participants' lexical decision responses using a computer mouse to primed and unprimed words. We predicted that participants would respond more efficiently to primed words compared to unprimed words. Indeed, across all of the dependent variables investigated (accuracy, reaction time, mouse trajectories) and across environments (in person, online), participants responded more efficiently to primed words than to unprimed words. We also performed additional exploratory analyses examining long-term repetition priming effects for nonwords. Across environments (in person, online), participants had more errors to primed nonwords than to unprimed nonwords, but there were no differences in reaction times and mouse trajectories. The current data demonstrating long-term repetition priming effects in mouse tracking are expected to motivate future investigations examining the time course of various long-term repetition priming effects for both words and nonwords.

Experimental Study on the Influence of Cognition and Emotion on Moral Judgment of College Students in Dilemma Situation

Objective: To study the influence of cognition and emotion on moral judgment of college students under the circumstance of whether the cognitive resources are occupied and whether the emotion is induced. Methods: This experiment uses a multi-factor mixed experiment method to divide experiments and groups. Experiment 1 uses a two-factor mixed experimental design of 2 (cognitive resource occupancy group, cognitive resource non-occupied group) × 3 (difficult situation type). Experiment 2 uses a two-factor mixed experimental design of 2 (emotion induction group, emotion induction and cognitive resource occupation group) × 3 (three types of dilemma situation types) is adopted. The dependent variable of this experiment (including Experiment 1 and Experiment 2) is the judgment response time and the judgment result is “Yes” (F) or “No” (J). Results: (1) The reaction time of the cognitive resource occupancy group was significantly higher than that of the cognitive resource non-occupied group, and the cognitive resource occupancy group in the three types of dilemma situations of high personal involvement, low personal involvement, and non-personal participation. There is no significant difference between the results of moral judgments and the cognitive resource non-occupied group. (2) In the three dilemmas of high personal involvement, low personal involvement, and non-personal participation, the emotion-induced group and the emotion-induced and cognitive resource occupation group have no significant differences in reaction time and moral judgment results. (3) In the three dilemmas of high personal involvement, low personal involvement, and non-personal participation, the reaction time difference between the cognitive resource occupation group and the emotionally induced and cognitive resource occupation is not significant, while In the dilemma of low personal involvement, the number of people in the cognitive resource occupation group whose moral judgment is “Yes” was significantly higher than that in the emotionally induced and cognitive resource occupation group. (4) In the three dilemmas of high personal involvement, low personal involvement, and non-personal participation, the reaction time of the emotionally induced group was significantly higher than that of the cognitive resource non-occupied group, and the moral judgment results of the two groups were both There is no significant difference. Conclusion: When the occupation of cognitive resources and the induction of emotions will signifi- cantly affect the response of individual moral judgments, different types of dilemmas will significantly affect the results of individual moral judgments.

Distinct Effects of Anxiety and Depression on Updating Emotional Information in Working Memory

Anxiety and depression have been shown to negatively influence the processing of emotional information in working memory. However, most studies have examined anxiety-related or depression-related working memory deficits independently, without considering their high co-morbidity. We tested the effects of emotional valence on working memory performance among healthy young adults with varying levels of anxiety and depressive symptoms. Ninety young adults aged between 18-24 (51 female) completed an emotional 2-back task in which positive, negative, and neutral images were presented. Multi-level modeling was used to examine anxiety and depressive symptoms as predictors of response accuracy and latency across the three emotional valence conditions. The results showed that participants responded to negative images with the highest accuracy and to positive images with the lowest accuracy. Both negative and positive images elicited slower responses than neutral images. Importantly, we found that more severe anxiety symptoms predicted a smaller difference in response accuracy between negative and neutral stimuli, whereas more severe depressive symptoms predicted a larger updating reaction time difference between positive and neutral stimuli. These findings demonstrated the uniquely anxiety-related deficits in processing negative contents and the uniquely depression-related deficits in updating positive contents in working memory, thus highlighting the necessity of novel cognitive bias modification interventions targeting the anxiety-specific and depression-specific deficits in working memory.

Effect of Premenstrual Stress on Reaction Time among Medical and Dental Students of a Medical College in Kathmandu, Nepal

The cyclical variation of ovarian hormones during the menstrual cycle has been implicated as the causative factor for many psychological and physical symptoms referred as premenstrual syndrome (PMS) causing varying degree of stress in females. This study is aimed to find out whether premenstrual stress might cause any alteration in the visual reaction time (VRT) in pre-menstrual and post-menstrual phase. Reaction time is an efficient non-invasive tool to evaluate the sensorimotor efficacy of a person. A cross sectional observational study was carried out in consenting and regularly menstruating 86 undergraduate medical and dental students of age ranging from 18-22 years, for a study period of April 2022 to June 2022. PMS was screened by using the PSST (premenstrual symptoms screening tool) to evaluate the incidence of PMS and the degree of premenstrual stress among the participants. All the participants showed some degree of PMS with 53.4% showing mild and 46.5% showing moderate to severe symptoms while none showed premenstrual dysphoric disorder (PMDD). A significant difference in body weight and visual reaction time (P&lt;0.0001) was observed between the premenstrual phase and postmenstrual phase (54.6 ± 7.23 kg Vs 54.2 ± 7.24 kg and 0.959 ± 0.271ms vs 0.811 ± 0.138ms, respectively) irrespective of the PMS degree. The results indicate that premenstrual stress do affect the sensorimotor efficacy in females having PMS.

The Angiotensin Antagonist Losartan Modulates Social Reward Motivation and Punishment Sensitivity via Modulating Midbrain-Striato-Frontal Circuits.

Social deficits and dysregulations in dopaminergic midbrain-striato-frontal circuits represent transdiagnostic symptoms across psychiatric disorders. Animal models suggest that interactions between the dopamine (DA) and renin-angiotensin system (RAS) may modulate learning and reward-related processes. The present study therefore examined the behavioral and neural effects of the Angiotensin II type 1 receptor (AT1R) antagonist losartan on social reward and punishment processing in humans. A preregistered randomized double-blind placebo-controlled between-subject pharmacological design was combined with a social incentive delay (SID) functional MRI (fMRI) paradigm during which subjects could avoid social punishment or gain social reward. Healthy volunteers received a single-dose of losartan (50 mg, n = 43, female = 17) or placebo (n = 44, female = 20). We evaluated reaction times (RTs) and emotional ratings as behavioral and activation and functional connectivity as neural outcomes. Relative to placebo, losartan modulated the reaction time and arousal differences between social punishment and social reward. On the neural level the losartan-enhanced motivational salience of social rewards was accompanied by stronger ventral striatum-prefrontal connectivity during reward anticipation. Losartan increased the reward-neutral difference in the ventral tegmental area (VTA) and attenuated VTA associated connectivity with the bilateral insula in response to punishment during the outcome phase. Thus, losartan modulated approach-avoidance motivation and emotional salience during social punishment versus social reward via modulating distinct core nodes of the midbrain-striato-frontal circuits. The findings document a modulatory role of the renin-angiotensin system in these circuits and associated social processes, suggesting a promising treatment target to alleviate social dysregulations.SIGNIFICANCE STATEMENT Social deficits and anhedonia characterize several mental disorders and have been linked to the midbrain-striato-frontal circuits of the brain. Based on initial findings from animal models we here combine the pharmacological blockade of the Angiotensin II type 1 receptor (AT1R) via losartan with functional MRI (fMRI) to demonstrate that AT1R blockade enhances the motivational salience of social rewards and attenuates the negative impact of social punishment via modulating the communication in the midbrain-striato-frontal circuits in humans. The findings demonstrate for the first time an important role of the AT1R in social reward processing in humans and render the AT1R as promising novel treatment target for social and motivational deficits in mental disorders.

Analysis of plantar impact characteristics of walking in patients with flatfoot according to basic mechanical features and continuous wavelet transform

Flatfoot is a common foot deformity, and the collapse of the arch structure affects the foot cushioning during walking. A growing number of scholars have found that the analysis of the impact force should be combined with both the magnitude and the frequency of the impact force. Therefore, the aim of this study is to investigate the plantar impact characteristics of flatfoot patients and normal foot people at different load-bearing buffer stage from the time and frequency domains. Sixteen males with flatfoot and sixteen males with normal foot were recruited to walk on the plantar pressure test system at the same step speed, and the vertical ground reaction force data were collected from the heel contact stage and the arch support stage. The differences in the frequency domain of the ground reaction force between the flatfoot and the normal foot in the two stages were analyzed according to the basic mechanical characteristics and the continuous wavelet transform. Independent sample t-test was used to compare the baseline data of subjects, and the differences in foot impact force characteristics at different stages of foot type and weight-bearing cushion phase were compared by two-factor repeated measures Analysis of Variance. 1) In terms of basic mechanical characteristics, In both groups for flatfoot patients and normal foot people, the peak ground reaction force was higher in the arch support stage compared to the heel contact stage (Pflatfoot&amp;lt;0.001, Pnormal foot&amp;lt;0.001), and the load rate of force change was smaller in this stage (Pflatfoot&amp;lt;0.001, Pnormal foot&amp;lt;0.001). However, no differences in peak ground reaction force and time of occurrence were found between flatfoot and normal foot in the two stages (p &amp;gt; 0.05), in the arch support stage, the force change load rate of patients with flatfoot was lower than that of normal foot people (p = 0.021). 2) The results of time and frequency domain characteristics showed that during the heel contact and the arch support stage, no significant differences in the maximum signal power as well as the corresponding time and the frequency of the main impact force between the normal foot and the flatfoot were found. In both flatfoot and normal foot types, compared with the foot heel contact stage, the maximum signal power in the arch support stage was higher (Pflatfoot &amp;lt; 0.001, Pnormal foot&amp;lt;0.001), and the corresponding impact frequency was smaller (Pflatfoot = 0.002, Pnormal foot = 0.004). Once the step speed was controlled, the flatfoot patients only showed a smaller impact force load rate in the arch support stage, which may be related to their lower arch rigidity. The characteristics of the impact force in different stages of walking support period were different in time and frequency domain, suggesting that there may be differences in the function of various parts of the foot.

The Account of the Effect of Switch Probability on Switch and Mixing Costs: An ERP Study in a Cued Task-switching Paradigm.

Whether the effect of switch probability on switch and mixing costs is explained by an activation or preparation account is unclear. To investigate the account of the effect of switch probability on switch and mixing costs. We used a cued task-switching paradigm with three switch probabilities (high, 75%; medium, 50%; and low, 25%) with 19 healthy young adults and recorded the cue- and target-locked event-related potentials (ERPs) and behavioral performance. The task included switch and stay trials under high, medium, and low switch conditions, as well as pure trials. There was no significant difference in reaction time (RT) in switch and mixing costs between the high and medium switch conditions. The RT in switch and mixing costs in the high and medium switch conditions was significantly less and more than in the low switch condition, respectively. The cue-locked ERPs revealed significant effects on mixing costs (stay - pure) that were cue early frontal positivity (260-300 ms) in the high and medium switch conditions, and on switch costs (switch - stay) that were cue early central positivity (240-260 ms) in the low switch condition. Moreover, the target-locked ERPs of the mixing costs revealed significant effects on mixing costs that were target P3b (440-540 ms) in all three switch conditions, and on switch costs that were target P3b in the medium and low switch conditions. The effect of switch probability on switch and mixing costs is explained by the activation account.

Pandemic publishing: A bibliometric review of COVID‐19 research in the crisis and disaster literature

Iconic events have traditionally instigated progression in the fields of crisis and disaster science. In the wake of the COVID-19 pandemic, the pressing question is how this global health emergency impacted the research agendas of our field. We reviewed contributions in ten important crisis and disaster journals in the two and a half years following the COVID-19 outbreak from 1 January 2020 to 30 June 2022. Specifically, we conducted a bibliometric review using thematic mapping analysis to distill the major themes covered by the emerging COVID-19 literature within crisis and disaster science (N = 239 articles). Our results indicate that several well-known topics are applied to the COVID-19 pandemic, such as risk, crisis communication, governance, resilience and vulnerability. The pandemic also gave rise to new topics, such as citizen behavior, state power, and the business and mental health impact of crisis measures. Several studies are already looking ahead by identifying lessons for preparedness and mitigation of future pandemics. By taking stock of the surge of COVID-19 studies while this academic literature is still taking shape, this review sets the stage for future contributions to the crisis and disaster literatures. It provides valuable lessons for what topics are studied and what themes need more attention. The COVID-19 pandemic is destined to become an iconic event for our literature that not only strengthens and deepens existing debates, but also clearly offers the opportunity to draw in new perspectives and broaden the horizon of crisis and disaster science.

Spatial biases in inhibition of return

ABSTRACT Inhibition of return (IOR) describes the phenomenon that reaction times (RT) to a target which appears at a previously cued location are slowed down. Spalek and Hammad ([2004]. Supporting the attentional momentum view of IOR: Is attention biased to go right? Perception & Psychophysics, 66(2), 219–233. https://doi.org/10.3758/BF03194874) reported that IOR effects were smaller at a lower or right location, compared to an upper or left location. In contrast, Snyder and Schmidt ([2014]. No evidence for directional biases in inhibition of return. Psychonomic Bulletin & Review, 21(2), 432–435. https://doi.org/10.3758/s13423-013-0511-3) argued that IOR is unaffected by spatial biases and that any observed differences are better explained by general reaction time differences depending on the target’s location. In two experiments (both N = 31), we aimed to test both diverging predictions by presenting cue and target at four locations along the vertical and horizontal axis. Controlling for a main effect of RTs at different target locations, we still observed a spatial bias on IOR, in that the effect was smaller at the lower than the upper target location. We also found a comparable spatial bias on the IOR-related phenomenon of early facilitation (EF). The results suggest that the magnitude and occurrence of both IOR and EF are affected by spatial configurations. Similarities with spatial biases on other visual phenomena as well as theoretical implications are discussed.

The effect of different types of physical activity on cognitive reaction time in older adults in China.

Aging is not only reflected in the degeneration of physiological functions but is also embodied in the decline of psychological and cognitive functions. The decline of cognitive function can reduce the quality of life in older adults, and even potentially cause Alzheimer's disease, which may lead to a heavy burden on patients, families, and society. The purpose of this study was to investigate the effects of physical activity (PA) on cognitive reaction time in older adults. A cross-sectional survey design was used in this study. A total of 839 elderly subjects were recruited from Beijing and Shanghai. In total, 792 subjects met the inclusion criteria (age > 60 years, without disability, speech, and hearing impairment), including 384 men (age:67.7 ± 5.7 years) and 408 women (age: 68.2 ± 5.8 years). The PA was assessed by the Physical Activity Scale for the Elderly (PASE). All kinds of PA were divided into three levels: "Low" (< 50% average score), "Moderate" (50-150% average score), and "High" (>150% average score). The reaction time of subjects was measured by the selective reaction tester (Model: CSTF-XF, TFHT, Beijing, China). For leisure-time PA, the results showed that the cognitive reaction time of older adults in the "Low" group (1.11 ± 0.32 s) was significantly longer than that in the "Moderate" group (1.05 ± 0.30 s, p < 0.01) and the "High" group (0.99 ± 0.28 s, p < 0.01). For housework PA, there was no significant difference in the cognitive reaction time among the three groups ("Low": 1.09 ± 0.31 s; "Moderate": 1.07 ± 0.31 s; "High": 1.05 ± 0.28 s, p > 0.05). For work-related PA, the results showed that the cognitive reaction time of older adults in the "Low" group (1.09 ± 0.30 s) was significantly longer than that in the "High" group (0.99 ± 0.28 s) and the "Moderate" group (1.03 ± 0.32 s, p < 0.01). The PA has a positive effect on reducing cognitive reaction time in older adults. It is recommended that older adults maintain a moderate level of leisure PA and work-related PA to delay the decline in cognitive reaction time.

Exploring Brain Activation of Single-Digit and Double-digit in Familiar and Unfamiliar Numerals: A Functional MRI Study

The ability to symbolise numbers using numerals is unique to humans and the acquisition of this ability needs to be done via learning [1]. Repeated exposure to sensory input can result in learning-induced alterations to the brain, forming memory engrams that are crucial for memory storage and retrieval [2]. Familiarity is an important factor that affects memory performance because familiar stimuli tend to have stronger memory strength with pre-existing knowledge representation stored in long-term memory, while unfamiliar or novel stimuli do not [1,3]. Past studies have suggested a few putative Number Form Area (NFA), located in the ventral occipitotemporal gyrus, are involved in processing visual number symbols [4 – 6]. It has been put forward that the acquisition of the semantic information of the numerical symbols might be a prerequisite for the activation of the NFA. However, much of its semantic information remains unknown. Figure 1 presented the conceptual framework of the present study.&#x0D; &#x0D; The present study aims to explore the brain activation associated with familiar and unfamiliar numerals of single-digit and double-digit. The targeted population of the present study will be Malaysian young adults between the age ranges of 18 to 30 years old. The present study will employ a quantitative cross-sectional observational research design. In particular, a within-subjects experimental study design with two factors: type of familiarity (familiar vs. unfamiliar) and the number of digits (single-digit vs. double-digit), will be used to measure the dependent variables including reaction time, accuracy, and brain activations of each participant in all experimental conditions: (1) familiar single-digit, (2) familiar double-digit, (3) unfamiliar single-digit, and (4) unfamiliar double-digit. An fMRI block design paradigm will be utilised, where the participants will be presented with single-digit and double-digit familiar (Chinese) numerals and unfamiliar (Arabic) numerals during the learning (encoding) phase and will be asked to complete the forced-choice memory task during the memory (retrieval) phase. In the experiment, participants’ structural and functional brain images will be collected using 3-Tesla Achieva MRI Scanner (Achieva, Philips, the Netherlands). Behavioural measurements such as reaction time and accuracy of the answer will be recorded based on the responses given by the participants during the fMRI task. Two-way repeated-measures ANOVA tests will be performed to compare the mean difference in reaction time, accuracy, and brain activation between the conditions. The brain activation will undergo pre- and post-processing using Matlab MATLAB software, Statistical Parametric Mapping 12, CONN toolbox and MarsBar toolbox.&#x0D; A significantly shorter reaction time and higher accuracy are expected to be observed in familiar as compared to unfamiliar conditions because familiar stimuli are being encountered relatively often in different contexts, which are likely to have broader retrieval contexts and stable mental representation stored in the long-term memory. Besides, it is predicted that brain areas such as the thalamus and the NFA will be highly engaged during the familiar conditions because thalamic nuclei have been reported to underpin familiarity memory [3] and the NFA has been put forward to hold a role in processing meaningful visual numerical symbols [4]. As for unfamiliar condition, the hippocampus and prefrontal cortex (PFC) is predicted to be highly engaged because unfamiliar numerals do not have pre-existing representation stored in the memory, thus it may trigger an active memory encoding process during the learning phase. The retrieval of memory of unfamiliar stimuli at a more recent time point after learning is thought to heavily rely on the hippocampus subregions and the PFC that are highly engaged during the memory encoding process.&#x0D; &#x0D; In conclusion, significantly better memory performances will be observed with familiar numerals as compared to unfamiliar numeral conditions. Differential neuronal activations will be observed between familiar and unfamiliar numeral conditions.

Predicting Time to Take-Off in a Countermovement Jump for Maximal Quickness From Upright and Squat Starting Positions

A countermovement jump (CMJ) is common in sport and often time-constrained. Little is known about contributors to quickness in jumps. This study examined effective predictors of time to take-off and effects of the starting position on reaction time and take-off time in a countermovement jump performed for quickness from upright and squat positions. Forty-nine collegiate athletes performed CMJs for quickness from upright and squatting starting positions to 75% of their maximal jump height. Several variables were calculated from the kinetic data related to jump performance. Correlation and multiple regression were used to determine variables related and predictive of time to take-off under both conditions. Paired t-tests evaluated differences in reaction and take-off times between conditions. In the upright condition, an increasing rate of force development and force, and decreasing time variables, impulses, and countermovement depth were associated with shorter time to take-off. The time to take-off prediction included rates of force development, force, time, and impulse. In the squat condition, shorter time to take-off was associated with lesser time variables, eccentric impulse, force at the end of the eccentric phase, and countermovement depth, and a greater rate of force development, concentric impulse, peak power, peak force, and reaction time. The time to take-off prediction equation included time to the bottom of the countermovement, time to peak force, and peak power. Reaction and take-off times were longer in the upright condition. Quick jump efficiency may be improved by strategies to increase maximum strength and the eccentric rate of force development while decreasing countermovement depth and time to bottom.

Exploring Brain Connectivity of Single-Digit and Double-Digit in Familiar and Unfamiliar Numerals: A Functional MRI Study

Learning and memory are closely related in a way that the ability to learn new information is done through working memory and the retrieval of the learned information is done through long-term memory [1]. Over the years, a keen interest in investigating the functional network and interaction in the brain regions during processing number magnitudes has increased among cognitive neuroscientists [2]. The majority of studies related to brain connectivity, especially on numeral cognition focus on children as these investigations could provide insight into neurodevelopmental performance [3].&#x0D; &#x0D; In the current study, we aim to explore brain connectivity associated with familiar and unfamiliar numerals of single-digit and double-digit among young adults. Figure 1 demonstrates the conceptual framework of the current study. This is a quantitative experimental design study that uses a combination of cognitive performance assessment and task-based fMRI block design to measure brain connectivity during learning and retrieval of the acquired information. Fifteen healthy young Malaysian adults in the age range of 18-30 years old who meet the inclusion criteria will be recruited via convenience sampling. Participants will be in one group performing two categories of tasks namely familiar (Chinese) and unfamiliar (Arabic) with two conditions each (single-digit and double-digit). A 3-Tesla MRI Philips Achieva (Philips Medical Systems, Best, Netherlands) scanner with a 32-channel SENSE head coil will be used for data acquisition.&#x0D; Descriptive statistics will be used to summarise the socio-demographic characteristics of subjects. The mean difference in reaction time and accuracy of answers for single and double-digit in familiar and unfamiliar numerals will be analysed using two-way repeated-measures ANOVA and reported. The pre-processing of the fMRI images will be carried out using MATLAB software, Statistical Parametric Mapping 12, and CONN toolbox. The identification and comparison of the brain's functional connectivity will be done using the GIFT toolbox and Statistical Parametric Mapping 12. Results will be reported in the form of figures and tables.&#x0D; &#x0D; Both familiar and unfamiliar numerals are expected to activate the fronto-parietal-occipital networks by extracting the network from the cognitive-control domain, sub-cortical domain, and visual domain but with different connectivity values. Unfamiliar numerals are anticipated to have higher connectivity values than familiar numerals. Similar findings are expected to double and single digits, whereby higher connectivity values in double digits than in the single digits. The limited studies on functional connectivity show the main regions involved in mathematic processing are the inferior frontal gyrus (IPG), intraparietal sulcus (IPS), and inferior temporal gyrus (ITG) [4]. The outcome of this study would be beneficial as it could provide baseline data to investigate abnormalities of brain connectivity in learning and memory-related to numerical cognition among the young adult population.&#x0D;

Effect of Sensory Modality on Reaction Time in Individuals with Auditory Neuropathy Spectrum Disorder

PurposeTo investigate and compare the reaction time of individuals with auditory neuropathy in three modalities, auditory, visual, and audio-visual. The reaction time of individuals with auditory neuropathy was also compared with those with normal hearing. The relationship between reaction time across modalities and the duration of hearing loss in auditory neuropathy was also investigated. Methods and MaterialsThe reaction time of adults with auditory neuropathy and those with normal hearing was measured in the three modalities using the Choice reaction time task. ResultsThe auditory neuropathy group significantly had a longer reaction time than the normal hearing in all modalities. The trend of the mean reaction time differed across groups. Further, a significant difference in reaction time of the auditory neuropathy group was noted between auditory and visual mode, auditory and audio-visual mode. However, no significant difference between visual and audio-visual modalities was noted in reaction time. ConclusionSignificantly longer reaction time in auditory neuropathy is presumed to have resulted from neural conduction delay and impaired processing. The auditory neuropathy group can utilize visual cues for faster processing, and the study recommends an audio-visual mode for their management. In addition, the duration of hearing loss in auditory neuropathy had no relationship with reaction time across all modalities.

Investigating sentence processing and working memory in patients with mild Alzheimer and elderly people.

Linguistic disorders are one of the common problems in Alzheimer's disease, which in recent years has been considered as one of the key parameters in the diagnosis of Alzheimer (AD). Given that changes in sentence processing and working memory and the relationship between these two activities may be a diagnostic parameter in the early and preclinical stages of AD, the present study examines the comprehension and production of sentences and working memory in AD patients and healthy aged people. Twenty-five people with mild Alzheimer's and 25 healthy elderly people participated in the study. In this study, we used the digit span to evaluate working memory. Syntactic priming and sentence completion tasks in canonical and non-canonical conditions were used for evaluating sentence production. We administered sentence picture matching and cross-modal naming tasks to assess sentence comprehension. The results of the present study revealed that healthy elderly people and patients with mild Alzheimer's disease have a significant difference in comprehension of relative clause sentences (P <0.05). There was no significant difference between the two groups in comprehension of simple active, simple active with noun phrase and passive sentences (P> 0.05). They had a significant difference in auditory and visual reaction time (P <0.05). Also there was a significant difference between the two groups in syntactic priming and sentence completion tasks. However, in non-canonical condition of sentence completion, the difference between the two groups was not significant (P> 0.05). The results of the present study showed that the mean scores related to comprehension, production and working memory in people with mild Alzheimer's were lower than healthy aged people, which indicate sentence processing problems at this level of the disease. People with Alzheimer have difficulty comprehending and producing complex syntactic structures and have poorer performance in tasks that required more memory demands. It seems that the processing problems of these people are due to both working memory and language problems, which are not separate from each other and both are involved in.

Abrupt vs. gradual visual onsets in go/no-go sustained attention tasks.

Two experiments compared both average performance and changes in performance across time in abrupt- and gradual-onset sustained attention tasks. Experiment1 compared abrupt- and gradual-onset digits. In conditions where the digits onset and offset abruptly and appeared only briefly, similar to typical conditions in the Sustained Attention to Response Task (SART), participants committed more errors on no-go trials and responded faster overall, indicative of a shift in the speed/accuracy tradeoff toward speed. When the digits abruptly onset but remained on-screen for a longer period of time, there were no differences in no-go error rates, hit rates, or reaction time (RT) variability, but participants still emitted faster RTs overall. Experiment2 compared abrupt- and gradual-onset images. Similar to Experiment1, abrupt-onset, short-duration images induced more no-go errors and faster RTs, but also more RT variability and reduced hit rates. In the abrupt-onset, long-duration condition, again the only performance difference was a decrease in average RTs. We discuss implications for using these two types of tasks in sustained attention research.