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A common finding across numerous response time (RT) paradigms is that the mean RT in one trial depends strongly on the characteristics of the immediately preceding trial. Although such sequential effects have usually only been considered within each single paradigm in isolation from the others, there are important similarities across paradigms between the theoretical accounts of these effects. However, so far there has been no systematic comparison of sequential effects across paradigms. To investigate the possible relationships between sequential effects in different paradigms, we conducted an experiment examining sequential effects in visual search, two-choice RT, interference, and task-switching paradigms, using methods designed to maximize the similarity of stimuli and responses across paradigms. Detailed analyses of the observed RT distributions were carried out using both descriptive (e.g., ex-Gaussian) and process-oriented (e.g., diffusion models) methods. The results reveal significant empirical similarities and differences between the sequential effects observed across different paradigms, and in some cases even across different conditions within a single paradigm. Furthermore, the sequential effects are more similar to one another for some pairs of paradigms than for others. These results imply that some cognitive processes eliciting sequential effects are shared across paradigms while others seem to be paradigm-specific.

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We provide an alternative psychometric perspective on the empirical statistical dependencies observed between response accuracy residuals (RARs) and response time residuals (RTRs) in the context of the van der Linden model. This perspective emphasizes the RAR (or parts of the RAR) as being exogenous and having a directional influence on response time. Our simple and theoretically justifiable perspective adds to previous joint response time/accuracy models and comports with recent generalizations of the D-diffusion IRT model incorporating person-by-item interactions, and thus similarly reproduces many of the recently highlighted empirical findings concerning the associations between RARs and RTRs. Using both empirical and simulation-based results, we show how our psychometric perspective has both applied and interpretational implications. Specifically, it would suggest that (1) studies of item parameter estimate heterogeneity in relation to response times may reflect more of a psychometric artifact (due to the exogenous effects of the RARs) as opposed to providing insights about the response process (e.g., the application of different response strategies) and that (2) efforts to use RTRs as indicators of latent proficiency should attend to the anticipated interactions between the latent proficiency and RAR on response times. The validity of our psychometric perspective against alternatives likely relies on appeals to theory; the best perspective to take may vary depending on the test setting.

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Introduction: This study investigates the log data and response behavior from invigilated in-person electronic timed exams at the University of Veterinary Medicine Hannover, Foundation, Germany. The primary focus is on understanding how various factors influence the time needed per exam item, including item format, item difficulty, item discrimination and character count. The aim was to use these results to derive recommendations for designing timed online distance examinations, an examination format that has become increasingly important in recent years. Methods: Data from 216,625 log entries of five electronic exams, taken by a total of 1,241 veterinary medicine students in 2021 and 2022, were analyzed. Various statistical methods were employed to assess the correlations between the recorded parameters. Results: The analysis revealed that different item formats require varying amounts of time. For instance, image-based question formats and Kprim necessitated more than 60 s per item, whereas one-best-answer multiple-choice questions (MCQs) and individual Key Feature items were effectively completed in less than 60 s. Furthermore, there was a positive correlation between character count and response time, suggesting that longer items require more time. A negative correlation could be verified for the parameters "difficulty" and "discrimination index" towards response time, indicating that more challenging items and those that are less able to differentiate between high- and low-performing students take longer to answer. Conclusion: The findings highlight the need for careful consideration of the ratio of item formats when defining time limits for exams. Regarding exam design, the literature mentions that time pressure is a critical factor, since it can negatively impact students' exam performance and some students, such as those with disabilities, are particularly disadvantaged. Therefore, this study emphasizes finding the right time limits to provide sufficient time for answering questions and reducing time pressure. In the context of unsupervised online exams, the findings of this study support previous recommendations that implementation of a stringent time limit might be a useful strategy to reduce cheating.

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This study reports the performance of 7 types of consumer grade passive Electronic Radon Integrating Monitors, ERIM (AlphaE, AER Plus, Canary, Corentium Pro, Radon Scout Home, Ramon and Wave) and passive etched track radon detectors. All monitors and passive radon detectors were exposed side by side for 2 periods of 3 months under controlled conditions in the UKHSA radon chamber and in a stainless steel container to an average radon concentration of 4781 Bq m-3and 166 Bq m-3, respectively. The performance of each individual monitor was compared with Atmos 12DPX and AlphaGUARD P30 reference instruments. The performance of the monitors was evaluated by estimating the biased, precision and measurement errors of each type. It was found that UKHSA passive radon detectors showed excellent performance (measurement error < 10%) at both higher and lower exposures. The AlphaE, Canary and Ramon showed excellent performance, with measurement error <10%, when they were exposed to radon concentrations between 4000 Bq m-3and 6000 Bq m-3in the UKHSA radon chamber. However, when the monitors were exposed to radon levels below the UK radon Action Level of 200 Bq m-3, the only ERIM which had a measurement error <10% was the Radon Scout Home. All other monitors showed a significant decrease in their performance with measurement errors ranging between 20% and 50%. The calibration factor, which is the ratio between the measured value (background is subtracted) and the reference value, was also studied. It was found that the calibration factors of individual monitors changed significantly. Calibration measurements in 2019 and in 2023 found that the percentage change varied between -46% and +63%. This shows the importance of initial and regular calibration, and maintenance of the monitors.

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BACKGROUND: Emotional clarity has often been assessed with self-report measures, but efforts have also been made to measure it passively, which has advantages such as avoiding potential inaccuracy in responses stemming from social desirability bias or poor insight into emotional clarity. Response times (RTs) to emotion items administered in ecological momentary assessments (EMAs) may be an indirect indicator of emotional clarity. Another proposed indicator is the drift rate parameter, which assumes that, aside from how fast a person responds to emotion items, the measurement of emotional clarity also requires the consideration of how careful participants were in providing responses. OBJECTIVE: This paper aims to examine the reliability and validity of RTs and drift rate parameters from EMA emotion items as indicators of individual differences in emotional clarity. METHODS: Secondary data analysis was conducted on data from 196 adults with type 1 diabetes who completed a 2-week EMA study involving the completion of 5 to 6 surveys daily. If lower RTs and higher drift rates (from EMA emotion items) were indicators of emotional clarity, we hypothesized that greater levels (ie, higher clarity) should be associated with greater life satisfaction; lower levels of neuroticism, depression, anxiety, and diabetes distress; and fewer difficulties with emotion regulation. Because prior literature suggested emotional clarity could be valence specific, EMA items for negative affect (NA) and positive affect were examined separately. RESULTS: Reliability of the proposed indicators of emotional clarity was acceptable with a small number of EMA prompts (ie, 4 to 7 prompts in total or 1 to 2 days of EMA surveys). Consistent with expectations, the average drift rate of NA items across multiple EMAs had expected associations with other measures, such as correlations of r=-0.27 (P<.001) with depression symptoms, r=-0.27 (P=.001) with anxiety symptoms, r=-0.15 (P=.03) with emotion regulation difficulties, and r=0.63 (P<.001) with RTs to NA items. People with a higher NA drift rate responded faster to NA emotion items, had greater subjective well-being (eg, fewer depression symptoms), and had fewer difficulties with overall emotion regulation, which are all aligned with the expectation for an emotional clarity measure. Contrary to expectations, the validities of average RTs to NA items, the drift rate of positive affect items, and RTs to positive affect items were not strongly supported by our results. CONCLUSIONS: Study findings provided initial support for the validity of NA drift rate as an indicator of emotional clarity but not for that of other RT-based clarity measures. Evidence was preliminary because the sample size was not sufficient to detect small but potentially meaningful correlations, as the sample size of the diabetes EMA study was chosen for other more primary research questions. Further research on passive emotional clarity measures is needed.

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Contextual cueing is a phenomenon in which repeatedly encountered arrays of items can enhance the visual search for a target item. This is widely attributed to attentional guidance driven by contextual memory acquired during visual search. Some studies suggest that children may have an immature ability to use contextual cues compared to adults, while others argue that contextual learning capacity is similar across ages. To test the development of context-guided attention, this study compared contextual cueing effects among three age groups: adults (aged 18-33 years, N = 32), teenagers (aged 15-17 years, N = 41), and younger children (aged 8-9 years, N = 43). Moreover, this study introduced a measure of response time variability that tracks fluctuations in response time throughout the experiment, in addition to the conventional analysis of response times. The results showed that all age groups demonstrated significantly faster responses in repeated than non-repeated search contexts. Notably, adults and teenagers exhibited smaller response time variability in repeated contexts than in non-repeated ones, while younger children did not. This implies that children are less efficient at consolidating contextual information into a stable memory representation, which may lead to less stable attentional guidance during visual search.

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Aim: The relationship between post-concussion kinesiophobia and clinical and functional reaction time (RT) beyond clinical recovery remains to be elucidated. Methods: College-aged participants with (n = 20) and without (n = 20) a concussion history completed patient-reported outcomes, and RT tasks. Kinesiophobia, symptoms and RTs were compared using t-tests. Linear regressions were performed to determine if kinesiophobia predicted RT measures and dual-task cost. Results: The concussion history group reported higher scores (p < 0.01) for all patient-reported outcomes. We observed significant single-task RT differences between groups (p = 0.013) such that those without a concussion history (m = 0.51s ± 0.08) were faster (m = 0.59s ± 0.12). There were no clinical or dual-task RT differences between groups (p > 0.05). Kinesiophobia significantly predicted single-task RT (R2 = 0.22). Discussion: Kinesiophobia should be considered when measuring RT.

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Shortening the prehospital emergency medical service (EMS) response time is crucial for saving lives and lowering mortality and disability rates in patients with sudden illnesses. Descriptive analyses of prehospital EMS response time and each component were conducted separately using ambulance trip data from the 120 Dispatch Command Centre in the main urban area of Chongqing in 2021, and then, logistic regression analyses were used to explore the influencing factors. The median prehospital EMS response time in the main urban area of Chongqing was 14.52 min and the mean was 16.14 min. A 44.89% of prehospital EMS response time exceeded 15 min. Response time was more likely to surpass this threshold during peak hours and in high population density areas. Conversely, lower probabilities exceeding 15 min were observed during the night shift, summer, and autumn seasons, and areas with a high density of emergency station. 33.28% of preparation time was >3 min, with the night shift and high population density areas more likely to be >3 min, while for the summer and autumn seasons, high Gross National Product (GDP) per capita areas had a lower likelihood of having preparation time >3 min. 45.52% of travel time was >11 min, with peak hours, summer and autumn, and high GDP per capita areas more likely to have had a travel time >11 min, while night shift and high emergency station density areas had a lower likelihood of travel time >11 min. The primary factors influencing prehospital EMS response time were shifts, traffic scenarios, seasons, GDP per capita, emergency station density, and population density. Relevant departments can devise effective interventions to reduce response time through resource allocation and department coordination, staff training and work arrangement optimisation, as well as public participation and education, thereby enhancing the efficiency of prehospital emergency medical services.

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Out-of-hospital cardiac arrest (OHCA) is a time-sensitive medical emergency that needs immediate interventions. COVID-19 affected the performance of the emergency medical service (EMS) system in pre-hospital care, including the management of cardiac arrest. This study aimed to identify the impact of the COVID-19 pandemic on pre-hospital management of out-of-hospital cardiac arrest and its outcome in Qom City, Iran. In this descriptive-analytical study, the data were collected from the electronic registration system of the EMS center in Qom, Iran. All OHCA patients who received resuscitation during COVID-19 and before COVID-19 were enrolled in the study. Data consisted of the characteristics of OHCA patients, EMS interventions and response times, and the outcome of OHCA. A P-value of <0.05 was deemed statistically significant. 630 OHCA patients in the COVID-19 period and 524 OHCA patients in the pre-COVID-19 period were included in the study. Endotracheal intubation and defibrillation were done more in the COVID-19 period than in the pre-COVID-19 period (50.2 % vs. 17 %, p<0.001 %, and 40.1 % vs. 22.5 %, p < 0.001, respectively). The EMS response time was longer during the COVID-19 pandemic (9.1 ± 3.9 min vs. 7.6 ± 1.4 min, p < 0.001). The rate of pre-hospital return of spontaneous circulation (ROSC) was lower in the COVID-19 period (15.6 % vs. 8.4 %, p < 0.001). According to univariate analysis, ROSC was predicted by COVID-19 (p < 0.001). However, COVID-19 was not the statistically significant independent predictor after multivariate analysis (p < 0.67). The COVID-19 pandemic period influenced OHCA and ROSC. Also, it affected pre-hospital management in the OHCA situation. The negative impact of COVID-19 on the EMS response reflected the need to know and remove barriers to managing crises such as COVID-19.

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Utilizing computer-based scales for cognitive and psychological evaluations allows for the collection of objective data, such as response time. This cross-sectional study investigates the significance of response time data in cognitive and psychological measures, with a specific focus on its role in evaluating sleep quality through the Insomnia Severity Index (ISI) scale. A mobile application was designed to administer scale tests and collect response time data from 2729 participants. We explored the relationship between symptom severity and response time. A machine learning model was developed to predict the presence of insomnia symptoms in participants using response time data. The result revealed a statistically significant difference (p < 0.01) in the total response time between participants with or without insomnia symptom. Furthermore, a strong correlation was observed between the severity of specific insomnia aspects and the response times at the individual questions level. The machine learning model demonstrated a high predictive Area Under the ROC Curve (AUROC) of 0.824 in predicting insomnia symptoms based on response time data. These findings highlight the potential utility of response time data to evaluate cognitive and psychological measures.

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The latest progress (the year 2021-2024) on multifunctional sensors based on silicone rubber is reported. These multifunctional sensors are useful for real-time monitoring through relative resistance, relative current change, and relative capacitance types. The present review contains a brief overview and literature survey on the sensors and their multifunctionalities. This contains an introduction to the different functionalities of these sensors. Following the introduction, the survey on the types of filler or rubber and their fabrication are briefly described. The coming section deals with the fabrication methodology of these composites where the sensors are integrated. The special focus on mechanical and electro-mechanical properties is discussed. Electro-mechanical properties with a special focus on response time, linearity, and gauge factor are reported. The next section of this review reports the filler dispersion and its role in influencing the properties and applications of these sensors. Finally, various types of sensors are briefly reported. These sensors are useful for monitoring human body motions, breathing activity, environment or breathing humidity, organic gas sensing, and, finally, smart textiles. Ultimately, the study summarizes the key takeaway from this review article. These conclusions are focused on the merits and demerits of the sensors and are followed by their future prospects.

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Every individual experiences negative emotions, such as fear and anger, significantly influencing how external information is perceived and processed. With the gradual rise in brain-behavior relationship studies, analyses investigating individual differences in negative emotion processing and a more objective measure such as the response time (RT) remain unexplored. This study aims to address this gap by establishing that the individual differences in the speed of negative facial emotion discrimination can be predicted from whole-brain functional connectivity when participants were performing a face discrimination task. Employing the connectome predictive modeling (CPM) framework, we demonstrated this in the young healthy adult group from the Human Connectome Project-Young Adults (HCP-YA) dataset and the healthy group of the Boston Adolescent Neuroimaging of Depression and Anxiety (BANDA) dataset. We identified distinct network contributions in the adult and adolescent predictive models. The highest represented brain networks involved in the adult model predictions included representations from the motor, visual association, salience, and medial frontal networks. Conversely, the adolescent predictive models showed substantial contributions from the cerebellum-frontoparietal network interactions. Finally, we observed that despite the successful within-dataset prediction in healthy adults and adolescents, the predictive models failed in the cross-dataset generalization. In conclusion, our study shows that individual differences in the speed of emotional facial discrimination can be predicted in healthy adults and adolescent samples using their functional connectivity during negative facial emotion processing. Future research is needed in the derivation of more generalizable models.

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Higher intraindividual variability (IIV) of response times is consistently noted in children with attention-deficit/hyperactivity disorder (ADHD). The current study investigated whether an ex-Gaussian estimate of IIV in children ages 6-13 years-old could differentiate between children with and without ADHD. Children completed a computerized go/no-go task to estimate trial-by-trial IIV and a continuous performance test (CPT) to estimate inattention and hyperactivity/impulsivity. Parents completed questionnaires assessing inattention and hyperactive/impulsive behaviors. IIV, commission errors, and attention problems as rated by parents were significantly greater in the ADHD group. Groups did not differ on errors of omission, but IIV was predictive of omission errors and parent ratings of inattention and hyperactivity/impulsivity. IIV predicted group membership (ADHD vs Control) whereas errors of omission did not. However, IIV did not improve diagnostic accuracy when parent ratings were used, such that parent ratings were superior at determining diagnosis. Current results support the use of IIV, based on the ex-Gaussian approach, as an objective measure of attention problems over omission errors on sustained attention CPT-type tasks. Additionally, while parent ratings of attention impairment remain the best predictor of ADHD diagnostic status, IIV may be helpful in determining when further assessment is required in the absence of those ratings.

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Out-of-hospital cardiac arrest (OHCA) is a major health issue throughout Europe. Due to limited knowledge about the epidemiology of OHCA in Europe, in 2011, the European Registry of Cardiac Arrest (EuReCa) project was established. Initially based on existing resuscitation registries in a few countries, the network expanded and in October 2014 the EuReCa ONE study was launched, bringing together 27 countries and showing that appropriate data acquisition (10,682 cases submitted) is feasible within Europe. EuReCa TWO was conducted from October to December 2017 and included 37,054 cases. EuReCa THREE data collection was carried out from September to November 2022 and data analysis is currently being conducted. EuReCa TWO and THREE studies generated more robust data, with both studies covering 3-month periods in 28 countries, respectively. While EuReCa TWO focused on the bystander, EuReCa THREE investigated the impact of time-related aspects (time from call to scene, time at scene, transport times and other) on resuscitation outcomes. EuReCa is a network supporting countries in their ambition to establishing continuously running registries as quality management tools and for scientific work.

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This study investigated whether a heavy-intensity priming exercise precisely prescribed within the heavy-intensity domain would lead to a greater peak-power output (POpeak) and a longer maximal oxygen uptake (V̇o2max) plateau. Twelve recreationally active adults participated in this study. Two visits were required: 1) a step-ramp-step test [ramp-incremental (RI) control], and 2) an RI test preceded by a priming exercise within the heavy-intensity domain (RI primed). A piecewise equation was used to quantify the V̇o2 plateau duration (V̇o2plateau-time). The mean response time (MRT) was computed during the RI control condition. The delta (Δ) V̇o2 slope (S; mL·min-1·W-1) and V̇o2-Y intercept (Y; mL·min-1) within the moderate-intensity domain between conditions (RI primed minus RI control) were also assessed using a novel graphical analysis. V̇o2plateau-time (P = 0.001; d = 1.27) and POpeak (P = 0.003; d = 1.08) were all greater in the RI primed. MRT (P < 0.001; d = 2.45) was shorter in the RI primed compared with the RI control. A larger ΔV̇o2plateau-time was correlated with a larger ΔMRT between conditions (r = -0.79; P = 0.002). This study demonstrated that heavy-intensity priming exercise lengthened the V̇o2plateau-time and increased POpeak. The overall faster RI-V̇o2 responses seem to be responsible for the longer V̇o2plateau-time. Specifically, a shorter MRT, but not changes in RI-V̇o2-slopes, was associated with a longer V̇o2plateau-time following priming exercise.NEW & NOTEWORTHY It remains unclear whether priming exercise extends the maximal oxygen uptake (V̇o2max) plateau and increases peak-power output (POpeak) during ramp-incremental (RI) tests. This study demonstrates that a priming exercise, precisely prescribed within the heavy-intensity domain, extends the plateau at V̇o2max and leads to a greater POpeak. Specifically, the extended V̇o2max plateau was associated with accelerated RI-V̇o2 responses.

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Reported perception of a new stimulus is either attracted toward or repelled away from task-irrelevant prior stimuli. While prevailing theories propose that the opposing serial biases may stem from distinct stages of information processing, the exact role of working memory (WM) in the serial bias remains unclear despite its consistent involvement in nearly all pertinent studies. Additionally, it is not well understood whether this bias is primarily driven by the biased representation itself or by the decision-making process for the new stimulus. In the present study, we used an orientation delayed estimation paradigm with an attention-demanding intervening task, designed to disrupt the maintenance of stimulus information to investigate the role of WM in serial bias. In the analysis, we scrutinized the trajectory of mouse reports and response time to investigate how the response unfolds over time. Our findings indicate that the serial bias went from repulsive to attractive when WM maintenance was interrupted by the intervening task, and that the associated response trajectories and response time exhibited patterns that cannot be explained by the biased representation alone. These results demonstrate that the task-irrelevant prior stimulus influences the decision for the new stimulus, with the direction of the bias being determined by attentional demand during WM maintenance, thereby placing significant constraints on existing theories on the serial bias effect.

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Valence (positive and negative) and content (embodied vs non-embodied) characteristics of visual stimuli have been shown to influence motor readiness, as tested with response time paradigms. Both embodiment and emotional processing are affected in Parkinson's disease (PD) due to basal ganglia dysfunction. Here we aimed to investigate, using a two-choice response time paradigm, motor readiness when processing embodied (emotional body language [EBL] and emotional facial expressions [FACS]) vs non-embodied (emotional scenes [IAPS]) stimuli with neutral, happy, and fearful content. We enrolled twenty-five patients with early-stage PD and twenty-five age matched healthy participants. Motor response during emotional processing was assessed by measuring response times (RTs) in a home-based, forced two-choice discrimination task where participants were asked to discriminate the emotional stimulus from the neutral one. Rating of valence and arousal was also performed. A clinical and neuropsychological evaluation was performed on PD patients. Results showed that RTs for PD patients were longer for all conditions compared to HC and that RTs were generally longer in both groups for EBL compared to FACS and IAPS, with the sole exception retrieved for PD, where in discriminating fearful stimuli, RTs for EBL were longer compared to FACS but not to IAPS. Furthermore, in PD only, when discriminating fearful respect to neutral stimuli, RTs were shorter when discriminating FACS compared to IAPS. This study shows that PD patients were faster in discriminating fearful embodied stimuli, allowing us to speculate on mechanisms involving an alternative, compensatory, emotional motor pathway for PD patients undergoing fear processing.

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Reacting and responding to an external stimulus is an important component of human performance, and they inform us about a participant's neurophysiological capabilities. Our purpose in this study was to determine whether reaction times (REACT), response times (RT), and countermovement jump (CMJ) performance differ when responding to an auditory (AUD) versus visual (VIS) stimulus. Participants were 17 college-aged volunteers (6 females and 11 males; M age = 23.0, SD = 3.4 years; M height = 174.57, SD = 10.37 cm; M body mass = 73.37, SD = 13.48 kg). Participants performed CMJs on force plates immediately upon receiving an AUD or a VIS stimulus. The AUD stimulus was a beep noise, while the VIS stimulus was a light on a screen in front of the participants. We determined REACT for the tibialis anterior (TA), medial gastrocnemius (GM), vastus lateralis (VL), and biceps femoris (BF) muscles to be the amount of time between stimulus onset and the initiation of the muscle's electromyographic (EMG) signal. We determined RT to be the amount of time between stimulus onset and the beginning of the participant's force production. We assessed CMJ performance via ground reaction forces during the unweighting, braking, and propulsive phases of the jump. We quantified EMG amplitude and frequency during each CMJ phase. We found RT to be faster to the AUD versus the VIS stimulus (p = .007). VL and BF muscles had faster REACT than TA and GM muscles (p ≤ .007). The AUD stimulus was associated with faster CMJ unweighting phase metrics (p ≤ .005). Thus, individuals may react and respond faster to an AUD versus VIS stimulus, with limited improvements in their subsequent physical performance.

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Current theories of decision-making propose that decisions arise through competition between choice options. Computational models of the decision process estimate how quickly information about choice options is integrated and how much information is needed to trigger a choice. Experiments using this approach typically report data from well-trained participants. As such, we do not know how the decision process evolves as a decision-making task is learned for the first time. To address this gap, we used a behavioral design separating learning the value of choice options from learning to make choices. We trained male rats to respond to single visual stimuli with different reward values. Then, we trained them to make choices between pairs of stimuli. Initially, the rats responded more slowly when presented with choices. However, as they gained experience in making choices, this slowing reduced. Response slowing on choice trials persisted throughout the testing period. We found that it was specifically associated with increased exponential variability when the rats chose the higher value stimulus. Additionally, our analysis using drift diffusion modeling revealed that the rats required less information to make choices over time. These reductions in the decision threshold occurred after just a single session of choice learning. These findings provide new insights into the learning process of decision-making tasks. They suggest that the value of choice options and the ability to make choices are learned separately and that experience plays a crucial role in improving decision-making performance.

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Recent advancements in marine technology have highlighted the urgent need for enhanced underwater acoustic applications, from sonar detection to communication and noise cancellation, driving the pursuit of innovative transducer technologies. In this paper, a new underwater thermoacoustic (TA) transducer made from carbon nanotube (CNT) sponge is designed to achieve wide bandwidth, high energy conversion efficiency, simple structure, good transient response, and stable sound response, utilizing the TA effect through electro-thermal modulation. The transducer has potential application in underwater acoustic communication. An electro-thermal-acoustic coupled simulation for the open model, sandwich model, and encapsulated model is presented to analyze the transient behaviors of CNT sponge TA transducers in liquid environments. The effects of key design parameters on the acoustic performances of both systems are revealed. The results demonstrate that a short pulse excitation with a low duty cycle could greatly improve the heat dissipation of the encapsulated transducer, especially when the thermoacoustic response time becomes comparable to thermal relaxation time.