Reaction Time Data Research Articles

Olympics: Improving the Competition Strategy in Each Skill Technique of Elite Swimmers for the 400 meters Freestyle

Background. In swimming championships, strategy setting is considered to be the main factor, especially in the middle and long-distance events. Implementing a strategic change can indirectly affect the final results. Objectives. The study aimed to find out whether there were any significant differences in reaction time (RT), final time (FT), and strategy for each split time (ST) in the men’s and women’s 400 meters freestyle events at the Olympic Games held in Tokyo (2021), Rio de Janeiro (2016), and London (2012). Materials and methods. This study used quantitative methods with a sample size of 48 athletes. The data source included using the secondary data. Descriptive statistics are presented in the form of means and standard deviations. The Shapiro–Wilk test was used to test the normality of the data. To compare RT, FT, and ST data, the one-way ANOVA test was conducted. The linear regression test was used to determine the effect of RT on the first ST. Results. The findings of this study indicate that there were differences in the RT of male athletes during the 3 Olympics. The study also revealed variations in average speed. In general, swimmers accelerated their speed at ST1 and ST8. This occurred at the Tokyo 2021 and Rio de Janeiro 2016 Olympics, while at the London 2012 Olympics, swimmers accelerated their speed only at ST1. Additionally, the results demonstrated that RT had an influence of 0.381 (14 %) on the first ST in male athletes, whereas the influence in female athletes was less marked — 0.066 (4 %). Conclusions. This study concludes that ST1 and ST8 are the most crucial components in the 400 meters freestyle swimming for both male and female athletes. Coaches and athletes must be very careful in carrying out special training at the tapering stage so that athletes can achieve the right time to produce the best performance.

Implicit Black identification among White non-Hispanic respondents and support for Black reparations

Abstract Theories of self-interest and ingroup-favouritism dominate Western thought. They give Black reparations in the US little chance of electoral success while African Americans remain a minority. Could Black reparations become feasible despite this limitation? I propose ‘relational identity theory’, a combination of Simon’s (1993) utility theory as well as Aron and Aron’s (1986) self-expansion theory, as an alternative to theories of self-interest and ingroup-favouritism. The theory allows for the inclusion of an outgroup in the self-concept. An online reaction-time procedure (n = 1,341) suggests that among White non-Hispanic respondents, implicit Black identification is the strongest predictor of support for Black reparations. Pooled reaction-time data from three studies involving 1,594 White non-Hispanic respondents suggests that implicit Black identification is based on feelings of closeness, warmth, and empathic concern for African Americans resembling Black group attachment. Significant implicit Black identifiers among White non-Hispanic respondents fall between Black non-Hispanic and other White non-Hispanic respondents in their race-related political opinions. ‘Relational identity theory’ can help economists, political scientists, and psychologists explain how majority domination (e.g. slavery and Jim Crow in the United States) could be overcome despite the democratic principle of majority rule. The theory suggests that Black reparations might become politically feasible one day.

Differences in biological motion perception associated with hearing status and age of signed language exposure.

This study investigates how American Sign Language (ASL) fluency and hearing status influence the perception of biological motion, using three point-light display (PLD) tasks. Prior research indicates that early exposure to ASL among deaf signers results in more rapid and effortless recognition of biological motion than hearing nonsigners, potentially due to the expertise in deciphering complex human movements or possibly due to neuroplasticity in deaf brains. However, it remains uncertain whether this advantage stems from signed language proficiency or the experience of being deaf. To explore this, we designed three PLD tasks involving viewing randomly moving dots, identifying a person from biological motion PLDs, and determining whether right-side up and inverted PLDs depict actions involving a ball. A diverse cohort of participants (N = 224) with varying ASL fluencies and hearing statuses completed the tasks online, providing us with reaction time and accuracy data. Our results demonstrate that earlier ASL exposure is associated with accuracy, especially on complex action identification tasks. Furthermore, we discovered robust evidence for a speed-accuracy trade-off in deaf participants, in which they performed more quickly but less accurately. The speed-accuracy trade-off was evident in the most difficult task, the action identification task. Further analysis of this deaf group revealed that earlier signed language acquisition led to higher accuracy in action identification task. We conclude that age of ASL exposure and hearing status both significantly contribute to variations in biological motion perception, with implications for understanding visual expertise and cognitive processing in both deaf and signing populations. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The Role of Gender in Cognitive Processing of Affective Linguistic Stimuli in Bilinguals

This study aims to compare the emotional reactions of bilingual men and women to affective valence by manipulating positive and negative linguistic stimuli. To achieve this aim, the semantic decision task was used. 56 Persian-English bilinguals, who were divided into two equal groups considering their gender (28 female and 28 male), were asked to decide whether the adjectives loaded with positive or negative valence (i.e., target words) were related in meaning to the preceding nouns (i.e., prime words). In order to find out whether there is any potential interaction between the valence of primes and targets, mixed factorial repeated measure ANOVA was run on reaction time and error rate data. The results of the present study on cognitive gender differences show that males and females, despite some few differences, generally follow a similar pattern in processing affective meaning of words in their second language.

B - 93 The Role of ex-Gaussian Parameters and Apathy in Reward Sensitivity Using a Modified Probabilistic Learning Task

Abstract Objective The current study examined the associations of apathy with attentional processes, indicated by ex-Gaussian (Ex-G) parameters of sensorimotor response speed and reward learning. Methods One hundred college-aged participants (M age = 20.32; SD = 3.69; 69 female) completed self-report measures of depression, apathy, and attentional control. Laboratory tasks included a choice reaction time (RT) task and a modified probabilistic learning task to assess sensorimotor processing and reward sensitivity. In the probabilistic learning task, participants selected the symbol associated with a high probability of gaining a monetary reward. Choice RT data were fit with Ex-G models, from which the parameter τ (bootstrapped sampling, 1000 iterations) was derived and used as the index of attentional lapses. Results A non-linear relationship was found between apathy and reward learning. Hierarchical regression was used to examine linear and higher-order relationships between apathy and behavioral indices (Ex-G τ and reward sensitivity). Results show that apathy explained none of the variance in reward learning (β = −0.005, p = 0.792, [bootstrapCI = −0.037, 0.026]). Incorporating apathy2 into the model led to significant R2 change (0.086), F(2, 89) = 0.4.142, p = 0.019, suggesting that as apathy increases, reward learning increases (β =0.006, p = 0.002, bootstrapCI = 0.002, 0.010]). Moreover, when controlling for depression, τ significantly contributes to the model, F(3, 89) = 4.142, p = 0.019, R2 = 0.17. Interactive effects revealed that at higher levels of apathy, higher Ex-G τ significantly decreases reward sensitivity (β = −0.003, p = 0.037, 95% bootstrapCI = [−0.006, −002]). Conclusions Higher levels of apathy and attentional lapses jointly reduced reward sensitivity, highlighting the role of task disengagement in apathy.

Executive functioning in posttraumatic stress disorder: Understanding how inhibition, switching, and test modality affect reaction times.

Posttraumatic stress disorder (PTSD) has been linked to deficits in executive functioning, but the literature suggests these associations are inconsistent. Results vary depending on the task used, test modality, and the specific subdomain being measured, such as inhibitory control (interference resolution, response inhibition) or set shifting (task switching, rule switching). Notably, deficits are more consistently observed in computerized tasks that measure precise reaction times (RTs) than in classic paper-and-pencil measures, but few studies have parsed specific executive functioning deficits in PTSD using detailed analyses of RT data. The present study used a cued-switching Stroop Task to examine both interference resolution and task switching in 28 veterans with PTSD and 28 age-matched controls. Each trial required attending to a randomly presented cue and responding to the specified target while ignoring irrelevant or opposing information. Analyses of RT distributions estimated both Gaussian (normal) and ex-Gaussian (exponential) parameters. Veterans with PTSD had slower and more variable RTs than the controls on trials that required ignoring conflicting information (interference resolution, d' = .68). These effects were confined to the normal distribution, not to excessively slow responses (as estimated by ex-Gaussian parameters). Veterans with PTSD also showed modestly slower RTs on trials that required switching between cues, but Bayesian evidence for this was weak, and measures by ex-Gaussian parameters were not significant. These results highlight the importance of examining executive functioning in PTSD with a more nuanced approach, as clarity around these deficits may have important implications for future intervention and rehabilitation strategies. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Value-based decision-making in regular alcohol consumers following experimental manipulation of alcohol value

BackgroundDevaluation of alcohol leads to reductions in alcohol choice and consumption; however, the cognitive mechanisms that underpin this relationship are not well-understood. In this study we applied a computational model of value-based decision-making (VBDM) to decisions made about alcohol and alcohol-unrelated cues following experimental manipulation of alcohol value. Method: Using a pre-registered within-subject design, thirty-six regular alcohol consumers (≥14 UK units per week) completed a two-alternative forced choice task where they chose between two alcohol images (in one block) or two soft drink images (in a different block) after watching videos that emphasised the positive (alcohol value), and separately, the negative (alcohol devalue) consequences of alcohol. On each block, participants pressed a key to select the image depicting the drink they would rather consume. A drift–diffusion model (DDM) was fitted to reaction time and choice data to estimate evidence accumulation (EA) processes and response thresholds during the different blocks in each experimental condition. Findings: In the alcohol devalue condition, soft drink EA rates were significantly higher compared to alcohol EA rates (p = 0.04, d = 0.31), and compared to soft drink EA rates in the alcohol value condition (p = 0.01, d = 0.38). However, EA rates for alcoholic drinks and response thresholds (for either drink type) were unaffected by the experimental manipulation. Conclusions: In line with behavioural economic models of addiction that emphasise the important role of alternative reinforcement, experimentally manipulating alcohol value is associated with changes in the internal cognitive processes that precede soft drink choice.

Perceived Audio-Visual Simultaneity Is Recalibrated by the Visual Intensity of the Preceding Trial.

A vital heuristic used when making judgements on whether audio-visual signals arise from the same event, is the temporal coincidence of the respective signals. Previous research has highlighted a process, whereby the perception of simultaneity rapidly recalibrates to account for differences in the physical temporal offsets of stimuli. The current paper investigated whether rapid recalibration also occurs in response to differences in central arrival latencies, driven by visual-intensity-dependent processing times. In a behavioural experiment, observers completed a temporal-order judgement (TOJ), simultaneity judgement (SJ) and simple reaction-time (RT) task and responded to audio-visual trials that were preceded by other audio-visual trials with either a bright or dim visual stimulus. It was found that the point of subjective simultaneity shifted, due to the visual intensity of the preceding stimulus, in the TOJ, but not SJ task, while the RT data revealed no effect of preceding intensity. Our data therefore provide some evidence that the perception of simultaneity rapidly recalibrates based on stimulus intensity.

Gradient boosted decision trees reveal nuances of auditory discrimination behavior.

Animal psychophysics can generate rich behavioral datasets, often comprised of many 1000s of trials for an individual subject. Gradient-boosted models are a promising machine learning approach for analyzing such data, partly due to the tools that allow users to gain insight into how the model makes predictions. We trained ferrets to report a target word's presence, timing, and lateralization within a stream of consecutively presented non-target words. To assess the animals' ability to generalize across pitch, we manipulated the fundamental frequency (F0) of the speech stimuli across trials, and to assess the contribution of pitch to streaming, we roved the F0 from word token to token. We then implemented gradient-boosted regression and decision trees on the trial outcome and reaction time data to understand the behavioral factors behind the ferrets' decision-making. We visualized model contributions by implementing SHAPs feature importance and partial dependency plots. While ferrets could accurately perform the task across all pitch-shifted conditions, our models reveal subtle effects of shifting F0 on performance, with within-trial pitch shifting elevating false alarms and extending reaction times. Our models identified a subset of non-target words that animals commonly false alarmed to. Follow-up analysis demonstrated that the spectrotemporal similarity of target and non-target words rather than similarity in duration or amplitude waveform was the strongest predictor of the likelihood of false alarming. Finally, we compared the results with those obtained with traditional mixed effects models, revealing equivalent or better performance for the gradient-boosted models over these approaches.

Dependency distance reflects L2 processing difficulty: Evidence from the relationship between dependency distance, L2 processing speed, and L2 proficiency

Aims and objectives: This study aims to investigate whether dependency distance (DD) can reflect L2 processing difficulty by exploring the relationship between DD, L2 processing speed, and L2 proficiency. Methodology: The sentences in a maze task were annotated based on dependency syntax to indicate L2 processing difficulty. The maze task then was used to capture the word-level and sentence-level processing speed. The task was successfully performed by 62 Chinese learners of English, who were assigned into an intermediate-level group and an advanced-level group according to their scores on an elicited imitation task (EIT) and a vocabulary and grammar test. Data and analysis: Reaction time (RT) data of processing word-level and sentence-level items were collected from the maze task. The DD-based estimates of word-level and sentence-level processing difficulty were calculated. Generalized linear regression models (GLMs) were employed to inspect the relationship between the DD-based estimate of processing difficulty, L2 processing speed, and L2 proficiency. Findings: Our results showed that DD significantly predicted L2 processing speed at both word and sentence levels, irrespective of participants’ L2 proficiency. As DD increased, advanced learners’ word-level processing time grew significantly slower than that of intermediate learners. Originality: Using psycholinguistic experiments, the study is one of the first attempts to empirically validate the effectiveness of DD in capturing L2 processing difficulty. Significance: Our findings suggest that DD is useful in predicting L2 processing difficulty, and the extent to which learners are able to efficiently process dependencies with increasing distance can differentiate their L2 proficiency levels.

Attentional Bias to Angry Faces: Contrasting Responses in Typically Developing Children and Children with Autism Spectrum Disorder

IntroductionHuman faces generally attract immediate attention. However, it has been found that children with autism spectrum disorder (ASD) tend to allocate relatively less attention to faces. Previous research showed that typically developing children (TD) exhibited an attentional bias to angry faces, regardless of their anxiety levels, but it’s unclear if this applies to children with ASD. Therefore, the present study aims to investigate attentional bias induced by angry and/or happy faces in children with ASD.ObjectivesWe explored attentional bias toward angry faces in both TD children and children with ASD. We hypothesize that while TD children will show attentional capture effects in response to angry faces, children with ASD will not exhibit such attentional bias to facial stimuli, irrespective of their emotional content.MethodsBy now, five ASD participants (all male) and 34 TD participants (17 male), aged 6-12, have completed a continuous performance task. In this task, irrelevant distractors (angry or happy faces) appeared and disappeared abruptly, while the orientation of the target changed every 1,250 ms. Participants were asked to respond as quickly and accurately as possible to the orientaiton of the target. We designated the time when the distractor first appeared as T1, and subsequent time intervals at 1,250 ms increments were labeled as T2, T3, and T4. The time intervals when no distractor was present were labeled as TB (baseline). If the reaction time (RT) at T1 was significantly slower compared to TB, it indicated attentional bias by the distractor.ResultsFor the RT data, separate repeated measures ANOVAs with 2 (emotion) * 5 (time) factors were conducted for each group. The results revealed a significant main effect of time (F(4, 132) = 17.59, p < .01) and a significant interaction between emotion and time (F(3.27, 107.74) = 4.92, p < .01) only in TD. Post hoc t-tests indicated that TD children exhibited significantly slower RT at T1 compared to TB, but this difference was observed only for angry faces (t(33) = 4.84, p < .01). In contrast, no significant effect was found in children with ASD. In other words, TD demonstrated attentional bias only when exposed to angry faces, while ASD children did not exhibit attentional bias to either emotion.ConclusionsThis study aimed to investigate attentional bias to angry faces in both TD and ASD children. The results indicate that TD children exhibited an attentional bias when exposed to angry faces, whereas ASD children did not display such bias. These findings are consistent with previous research suggesting that TD children tend to show attentional bias towards angry faces, regardless of their anxiety levels. Furthermore, the absence of attentional bias to angry faces in ASD suggests that their characteristic of reduced attention to faces may contribute to the lack of attentional bias towards angry faces.Disclosure of InterestNone Declared

Mental workload modulates the effects of baroreceptor afferents on sensorimotor processing

The heart–brain interaction is the main mechanism for maintaining normative physiological processes, and its dysregulation underlies the somatic symptoms of various mental disorders. Cortical inhibition, triggered by afferent signals from baroreceptor activation, induces systematic variations in sensorimotor responses within a cardiac cycle, with reaction times (RTs) slower at cardiac systole compared to diastole (known as cardiac cycle time effects). However, recent data suggest that baroreceptor afferents not only inhibit simple responses but also facilitate complex sensorimotor responses during cardiac systole. The mental workload that is implicated in complex responses may modulate the cardiac cycle time effects. The current study aimed to examine whether concurrent mental workloads influenced cardiac cycle time effects on sensorimotor processing. Using a dual-task paradigm, 47 participants (32 female; age = 21.9 ± 2.1 years) performed a choice RT task and a working memory (WM) task. Stimuli were presented during either cardiac systole or diastole. RT data were fitted using the ex-Gaussian distribution, and the parameters, mu and tau, were derived to indicate response speed and high-order attentional processes, respectively. The behavioral data were submitted to 2 (WM load) × 2 (cardiac timing) repeated measures analyses of variances. The results indicated that RT metrics were longer during cardiac systole than diastole under the no-load condition. However, WM load reversed the cardiac timing effects on response speed while inducing more attentional lapses. These findings suggest that concurrent WM load influences cardiac cycle time effects on sensorimotor processing via top-down resources.

Serial processing of proximity groups and similarity groups.

Proximity and feature similarity are two important determinants of perceptual grouping in vision. When viewing visual scenes conveying both grouping options simultaneously, people most usually detect proximity groups faster than similarity groups. This article demonstrates that perceptual judgments of grouping orientation guided by either proximity or contrast similarity are indicative of a sequential organization of grouping operations in the visual pathway, which lends a temporal processing advantage to proximity grouping (Experiment 1). Invoking the double-factorial paradigm, latent cognitive architecture for perceptual grouping is also investigated in a task with redundant signals (Experiment 2). Reaction time data from this task is assessed in terms of the race model inequality, workload capacity analysis, and interaction contrasts of means and survivor functions. Again, empirical benchmarks indicate serial processing of proximity groups and similarity groups, with a self-terminating stopping rule for processing. A subset of participants exhibit atypical performance metrics, hinting at possible individual differences in configural visual processing.

Distracted by Previous Experience: Integrating Selection History, Current Task Demands and Saliency in an Algorithmic Model

AbstractAttention can be biased by previous learning and experience. We present an algorithmic-level model of this selection history bias in visual attention that predicts quantitatively how stimulus-driven processes, goal-driven control and selection history compete to control attention. In the model, the output of saliency maps as stimulus-driven guidance interacts with a history map that encodes learning effects and a goal-driven task control to prioritize visual features. The model works on coded features rather than image pixels which is common in many traditional saliency models. We test the model on a reaction time (RT) data from a psychophysical experiment. The model accurately predicts parameters of reaction time distributions from an integrated priority map that is comprised of an optimal, weighted combination of separate maps. Analysis of the weights confirms selection history effects on attention guidance. The model is able to capture individual differences between participants’ RTs and response probabilities per group. Moreover, we demonstrate that a model with a reduced set of maps performs worse, indicating that integrating history, saliency and task information are required for a quantitative description of human attention. Besides, we show that adding intertrial effect to the model (as another lingering bias) improves the model’s predictive performance.

Clarifying Cognitive Control Deficits in Psychosis via Drift Diffusion Modeling and Attractor Dynamics.

Cognitive control deficits are prominent in individuals with psychotic psychopathology. Studies providing evidence for deficits in proactive control generally examine average performance and not variation across trials for individuals-potentially obscuring detection of essential contributors to cognitive control. Here, we leverage intertrial variability through drift-diffusion models (DDMs) aiming to identify key contributors to cognitive control deficits in psychosis. People with psychosis (PwP; N = 122), their first-degree biological relatives (N = 78), and controls (N = 50) each completed 120 trials of the dot pattern expectancy (DPX) cognitive control task. We fit full hierarchical DDMs to response and reaction time (RT) data for individual trials and then used classification models to compare the DDM parameters with conventional measures of proactive and reactive control. PwP demonstrated slower drift rates on proactive control trials suggesting less efficient use of cue information. Both PwP and relatives showed protracted nondecision times to infrequent trial sequences suggesting slowed perceptual processing. Classification analyses indicated that DDM parameters differentiated between the groups better than conventional measures and identified drift rates during proactive control, nondecision time during reactive control, and cue bias as most important. DDM parameters were associated with real-world functioning and schizotypal traits. Modeling of trial-level data revealed that slow evidence accumulation and longer preparatory periods are the strongest contributors to cognitive control deficits in psychotic psychopathology. This pattern of atypical responding during the DPX is consistent with shallow basins in attractor dynamic models that reflect difficulties in maintaining state representations, possibly mediated by excess neural excitation or poor connectivity.

An attention-based approach for assessing the effectiveness of emotion-evoking in immersive environment

Visual stimuli within an immersive virtual environment impact human perception and behavior in notably different ways compared to the real world. Previous studies have presented evidence indicating that individuals in various emotional states exhibit an unconscious attentional bias toward either positive or negative stimuli. However, whether these findings can be replicated within an immersive virtual environment remains uncertain. In this study, we devised an attention-based experiment to explore whether the correlation between participants' emotional states and the valence of visual stimuli influences their attentional bias. Participants (n=28) viewed 360-degree videos with varying valence levels (positive and negative) to evoke emotions. Subsequently, we utilized standard emotional human faces as stimuli to assess how the consistency in video valence and emotional faces affects reaction time (RT) in Go tasks and error rates in No-go tasks. We employed the Ex-Gaussian approach to analyze the RT data. The parameters—mu (μ), sigma (σ), and tau (τ)—were computed to denote response speed and attentional lapses, respectively. Our findings revealed a significant increase in tau (τ) when the valence of the video and emotional faces aligned. This suggests that the Go/No-go paradigm is effective in evaluating the impact of emotion-evoking stimuli within an immersive environment.

Isolating objective and subjective filling-in using the drift diffusion model.

Spatial context is known to influence the behavioral sensitivity (d') and the decision criterion (c) when detecting low-contrast targets. Of interest here is the effect on the decision criterion. Polat and Sagi (2007) demonstrated that, for a Gabor target positioned between two similar co-aligned high-contrast flankers, the observers' reports of seeing the target (Hit and False Alarm) decreased with increasing target-flanker distance. This effect was more pronounced when the distance was randomized within testing blocks compared to when it was fixed. According to signal detection theory (SDT), the latter result suggests that the decision criterion is adjusted to a specific distance-dependent combination of signal (S) and noise (N) when the S and N statistics are fixed, but not when they vary across trials. However, SDT cannot differentiate between changes in the decision bias (the criterion shift) and changes introduced by variations in S and N (the signal and noise shift). To circumvent this limitation of SDT, we analyzed the reaction time (RT) data within the framework of the drift diffusion model (DDM). We performed an RT analysis of the target-flanker interactions using data from Polat and Sagi (2007) and Zomet et al. (2008; 2016). The analysis revealed a stronger dependence on flankers for faster RTs and a weaker dependence for slower RTs. The results can be explained by DDM, where an evidence accumulation process depends on the flankers via a change in the rate of the evidence (signal and noise shift) and on observers' prior knowledge via a change in the starting point (criterion shift), leading to RT-independent and RT-dependent effects, respectively. The RT-independent distance-dependent response bias is attributed to the observers' inability to learn multiple internal distributions required to accommodate the distance-dependent effects of the flankers on both the signal and noise.

We don't know what you did last summer. On the importance of transparent reporting of reaction time data pre-processing

In behavioral, cognitive, and social sciences, reaction time measures are an important source of information. However, analyses on reaction time data are affected by researchers' analytical choices and the order in which these choices are applied. The results of a systematic literature review, presented in this paper, revealed that the justification for and order in which analytical choices are conducted are rarely reported, leading to difficulty in reproducing results and interpreting mixed findings. To address this methodological shortcoming, we created a checklist on reporting reaction time pre-processing to make these decisions more explicit, improve transparency, and thus, promote best practices within the field. The importance of the pre-processing checklist was additionally supported by an expert consensus survey and a multiverse analysis. Consequently, we appeal for maximal transparency on all methods applied and offer a checklist to improve replicability and reproducibility of studies that use reaction time measures.

Comparing intra‐individual variability on executive functioning tasks in individuals with Mild Cognitive Impairment and Dementia of the Alzheimer Type: Results from the ARMADA Study

AbstractBackgroundCognitive decline is most often assessed mean group differences on static measures of cognitive abilities (MacDonald et al., 2009). Another, perhaps more dynamic, method to understanding cognitive functioning is to evaluate variability in performance within an individual, termed intraindividual variability (IIV), which has been associated with reduction in gray matter and less efficient cognitive processing. Using results from a multi‐site, longitudinal ARMADA study that validated NIH Toolbox across the cognitive aging spectrum, we investigated whether IIV in reaction time processing can differentiate between older adults with normal cognition, mild cognitive impairment (MCI), or dementia of the Alzheimer type (DAT), as well as the relative magnitude of differences between groups.MethodAs part of the Advancing Reliable Measurement in Alzheimer’s Disease and cognitive Aging study (ARMADA; Weintraub et al 2020), participants completed the NIH Toolbox Cognition Battery, including two measures of executive functioning, Dimensional Change Card Sort and Flanker Inhibitory Control, which include granular reaction time data in milliseconds. We analyzed standard deviation and mean absolute deviation of item‐level data of all trials, correct trials only, and incorrect trials only for three groups: normal controls, those with amnestic MCI, and those with mild DAT.ResultWe observe large effect sizes of reaction time by clinical group, with the mild DAT group demonstrating mean standard error across trials of approximately .5 seconds throughout, compared with .25 seconds for MCI and .10 seconds for the control group (Figure 1). This translates to an approximate 5‐fold increase in processing speed in the most severe clinical group. Examining time trends, we see that while the NC and MCI group were faster as the test progressed; there is no similar learning effect for the mild DAT group. Similar effect sizes were observed for the Flanker test.ConclusionThis study represents one of the first studies to examine clinical performance using process data from two executive functioning measures on the NIH Toolbox across the cognitive aging spectrum. Future work will explore more definitions of IIV to determine which measure will maximally differentiate between established clinical groups and examine longitudinal differences.

Clinical Manifestations.

Cognitive decline is most often assessed mean group differences on static measures of cognitive abilities (MacDonald et al., 2009). Another, perhaps more dynamic, method to understanding cognitive functioning is to evaluate variability in performance within an individual, termed intraindividual variability (IIV), which has been associated with reduction in gray matter and less efficient cognitive processing. Using results from a multi-site, longitudinal ARMADA study that validated NIH Toolbox across the cognitive aging spectrum, we investigated whether IIV in reaction time processing can differentiate between older adults with normal cognition, mild cognitive impairment (MCI), or dementia of the Alzheimer type (DAT), as well as the relative magnitude of differences between groups. As part of the Advancing Reliable Measurement in Alzheimer's Disease and cognitive Aging study (ARMADA; Weintraub et al 2020), participants completed the NIH Toolbox Cognition Battery, including two measures of executive functioning, Dimensional Change Card Sort and Flanker Inhibitory Control, which include granular reaction time data in milliseconds. We analyzed standard deviation and mean absolute deviation of item-level data of all trials, correct trials only, and incorrect trials only for three groups: normal controls, those with amnestic MCI, and those with mild DAT. We observe large effect sizes of reaction time by clinical group, with the mild DAT group demonstrating mean standard error across trials of approximately .5 seconds throughout, compared with .25 seconds for MCI and .10 seconds for the control group (Figure 1). This translates to an approximate 5-fold increase in processing speed in the most severe clinical group. Examining time trends, we see that while the NC and MCI group were faster as the test progressed; there is no similar learning effect for the mild DAT group. Similar effect sizes were observed for the Flanker test. This study represents one of the first studies to examine clinical performance using process data from two executive functioning measures on the NIH Toolbox across the cognitive aging spectrum. Future work will explore more definitions of IIV to determine which measure will maximally differentiate between established clinical groups and examine longitudinal differences.