Choice Reaction Time Task Research Articles

Neuroticism Mediates the Association between Autistic Traits and Choice Reaction Time among Young Adults.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that influences an individual's cognitive functions and social interaction. While most studies have focused on children and adolescents diagnosed with ASD, elevated levels of autistic traits in subclinical populations may also influence individuals' daily functioning. Autistic traits are also linked to the Big Five personality. In particular, neuroticism (emotion instability) has been shown to be positively associated with autistic traits, which may contribute to behavioral symptoms of autistic traits. The present study aimed to investigate the association between autistic symptoms and sensorimotor processing among a subclinical population. One hundred young adults (Mage = 20.32 years; SD = 3.69 years; 69 female) completed a choice reaction time (RT) task, and their behavioral performance was analyzed using the ex-Gaussian modeling. The Autism Quotient (AQ) and the Ten-Item Personality Inventory (TIPI) were used to assess autistic traits and neuroticism, respectively. The mediation analysis was conducted to examine the behavioral mechanism through which autistic traits influence sensorimotor processing. The results showed that the AQ score was negatively correlated with RT and positively correlated with neuroticism score. Importantly, the mediation analysis indicated an indirect effect, suggesting that neuroticism mediates the association between the AQ score and RT. The findings indicated a possible mechanism of the association between autistic traits and sensorimotor responses and suggested that neuroticism should be included as an intervention target for ASD. The present study contributes to the research on autistic traits and has practical implications for future intervention programs to improve daily functioning among individuals with ASD.

The Relationships Between Reaction Time Scores and False Start Penalties of Offensive Linemen in the National Football League (NFL).

Each year in the United States, many factors are considered in the National Football League's draft process, including scouting reports, interviews, medical tests, and measures of players' strength, speed, anthropometry, and personality. Recently, an increased emphasis has been placed on players' psychometrically measured cognitive abilities. Historically, offensive linemen have been excluded from NFL research, since they do not have individual performance statistics. In this study, we attempted to fill that research gap by investigating correlates of offensive linemen's measured vigilance/impulsivity. We obtained archival player data from 85 offensive linemen in the years from 2014-2021 prior to each of these players' NFL draft. We then used false start penalties per game (FSPG) as an index of their vigilance/impulsivity (and general success) on the field, and we related those values to Reaction Time tests through hierarchical multiple regression analyses. After controlling for draft placement, these players' higher accuracy on a Choice Reaction Time task accounted for a statistically significant percentage of the variance associated with their FSPG statistics. We discuss the practical utility for player development of these and other cognitive assessments now used in the NFL.

Classifying Learning Speed Using Brain Networks and Psychological States: Unraveling the Interdependence Between Learning Performance, Psychological States, and Brain Functions.

Introduction The progression of performance learning (PL) may have complex relationships beyond mere concurrent occurrences and may influence each other. This study aimed to classify the speed of PL using a random forest based on brain network and stress state information and to identify the factors necessary for PL. In addition, this study also aimed to clarify the complex interdependent relationships between PL, psychological state, and brain function through these factors, using covariance structure analysis. Methods A total of 20 healthy individuals participated in a choice reaction time task, and brain function was measured using near-infrared spectroscopy (NIRS). Participants were divided into high-PL and low-PL groups based on the median difference in correct responses. Results Random forest analysis identified the left orbitofrontal area, right premotor cortex, right frontal pole, left frontal pole, left dorsolateral prefrontal cortex, and depression and anxiety as key factors. Covariance structure analysis revealed that depression and anxiety affected PL through the frontal pole and prefrontal cortex, suggesting a complex interplay between psychological state, brain function, and learning. Conclusions These findings suggest that psychological states influence brain networks, thereby affecting learning performance. Tailoring rehabilitation programs to address psychological states and providing targeted feedback may improve learning outcomes. The study provides insights into the theoretical and practical applications of understanding the brain's role in PL, as well as the importance of addressing psychological factors to optimize learning and rehabilitation strategies.

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.

Corticospinal excitability at rest outside of a task does not differ from task intertrial intervals in healthy adults.

Human corticospinal excitability (CSE) modulates during movement, when muscles are active, but also at rest, when muscles are not active. These changes in resting motor system excitability can be transient or longer lasting. Evidence from transcranial magnetic stimulation (TMS) studies suggests even relatively short periods of motor learning on the order of minutes can have lasting effects on resting CSE. Whether individuals are able to return CSE to out-of-task resting levels during the intertrial intervals (ITI) of behavioral tasks that do not include an intended motor learning component is an important question. Here, in twenty-five healthy young adults, we used single-pulse TMS and electromyography (EMG) to measure motor evoked potentials (MEPs) during two different resting contexts: (1) prior to engaging in the response task during which participants were instructed only to rest (out-of-task), and (2) ITI of a choice-reaction time task (in-task). In both contexts, five TMS intensities were used to evaluate possible differences in recruitment of corticospinal (CS) output across a range of inputs. We hypothesized resting state CSE would be greater during ITI than out-of-task rest, reflected in larger MEP amplitudes. Contrary to our hypothesis, we observed no significant difference in MEP amplitudes between out-of-task rest and in-task ITI, and instead found evidence of equivalence, indicating that humans are able to return to a stable motor resting state within seconds after a response. These data support the interpretation that rest is a uniform motor state in the healthy nervous system. In the future, our data may be a useful reference for motor disorder populations with an impaired ability to return to rest.

Cognitive Speed in Neurodegenerative Disease: Comparing Mean Rate and Inconsistency Within and Across the Alzheimer's and Lewy Body Spectra in the COMPASS-ND Study.

Alzheimer's disease (AD) and Lewy body disease (LBD) are characterized by early and gradual worsening perturbations in speeded cognitive responses. Using simple and choice reaction time tasks, we compared two indicators of cognitive speed within and across the AD and LBD spectra: mean rate (average reaction time across trials) and inconsistency (within person variability). The AD spectrum cohorts included subjective cognitive impairment (SCI, n = 28), mild cognitive impairment (MCI, n = 121), and AD (n = 45) participants. The LBD spectrum included Parkinson's disease (PD, n = 32), mild cognitive impairment in PD (PD-MCI, n = 21), and LBD (n = 18) participants. A cognitively unimpaired (CU, n = 39) cohort served as common benchmark. We conducted multivariate analyses of variance and discrimination analyses. Within the AD spectrum, the AD cohort was slower and more inconsistent than the CU, SCI, and MCI cohorts. The MCI cohort was slower than the CU cohort. Within the LBD spectrum, the LBD cohort was slower and more inconsistent than the CU, PD, and PD-MCI cohorts. The PD-MCI cohort was slower than the CU and PD cohorts. In cross-spectra (corresponding cohort) comparisons, the LBD cohort was slower and more inconsistent than the AD cohort. The PD-MCI cohort was slower than the MCI cohort. Discrimination analyses clarified the group difference patterns. For both speed tasks, mean rate and inconsistency demonstrated similar sensitivity to spectra-related comparisons. Both dementia cohorts were slower and more inconsistent than each of their respective non-dementia cohorts.

Subthalamic DBS does not restore deficits in corticospinal suppression during movement preparation in Parkinson’s disease

ObjectiveParkinson’s disease (PD) patients exhibit changes in mechanisms underlying movement preparation, particularly the suppression of corticospinal excitability – termed “preparatory suppression” – which is thought to facilitate movement execution in healthy individuals. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) being an attractive treatment for advanced PD, we aimed to study the potential contribution of this nucleus to PD-related changes in such corticospinal dynamics. MethodsOn two consecutive days, we applied single-pulse transcranial magnetic stimulation to the primary motor cortex of 20 advanced PD patients treated with bilateral STN-DBS (ON vs. OFF), as well as 20 healthy control subjects. Motor-evoked potentials (MEPs) were elicited at rest or during movement preparation in an instructed-delay choice reaction time task including left- or right-hand responses. Preparatory suppression was assessed by expressing MEPs during movement preparation relative to rest. ResultsPD patients exhibited a deficit in preparatory suppression when it was probed on the responding hand side, particularly when this corresponded to their most-affected hand, regardless of their STN-DBS status. ConclusionsAdvanced PD patients displayed a reduction in preparatory suppression which was not restored by STN-DBS. SignificanceThe current findings confirm that PD patients lack preparatory suppression, as previously reported. Yet, the fact that this deficit was not responsive to STN-DBS calls for future studies on the neural source of this regulatory mechanism during movement preparation.

Acute and Repeated Ashwagandha Supplementation Improves Markers of Cognitive Function and Mood.

Ashwagandha has been reported to reduce stress and attenuate cognitive decline associated with inflammation and neurodegeneration in clinical populations. However, the effects as a potential nootropic nutrient in younger populations are unclear. This study examined the effects of liposomal ashwagandha supplementation on cognitive function, mood, and markers of health and safety in healthy young men and women. 59 men and women (22.7 ± 7 yrs., 74.9 ± 16 kg, 26.2 ± 5 BMI) fasted for 12 h, donated a fasting blood sample, and were administered the COMPASS cognitive function test battery (Word Recall, Word recognition, Choice Reaction Time Task, Picture Recognition, Digit Vigilance Task, Corsi Block test, Stroop test) and profile of mood states (POMS). In a randomized and double-blind manner, participants were administered 225 mg of a placebo (Gum Arabic) or ashwagandha (Withania somnifera) root and leaf extract coated with a liposomal covering. After 60-min, participants repeated cognitive assessments. Participants continued supplementation (225 mg/d) for 30 days and then returned to the lab to repeat the experiment. Data were analyzed using a general linear model (GLM) univariate analysis with repeated measures and pairwise comparisons of mean changes from baseline with 95% confidence intervals (CI). Ashwagandha supplementation improved acute and/or 30-day measures of Word Recall (correct and recalled attempts), Choice Reaction Time (targets identified), Picture Recognition ("yes" correct responses, correct and overall reaction time), Digit Vigilance (correct reaction time), Stroop Color-Word (congruent words identified, reaction time), and POMS (tension and fatigue) from baseline more consistently with several differences observed between groups. Results support contentions that ashwagandha supplementation (225 mg) may improve some measures of memory, attention, vigilance, attention, and executive function while decreasing perceptions of tension and fatigue in younger healthy individuals. Retrospectively registered clinical trial ISRCTN58680760.

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.

Nocturnal Smartphone Use Affects Sleep Quality and Cognitive and Physical Performance in Tunisian School-Age Children.

Nocturnal smartphone use emits blue light, which can adversely affect sleep, leading to a variety of negative effects, particularly in children. Therefore, the present study aimed to determine the effect of acute (AC) (one night) and repeated (RC) (five nights) nocturnal smartphone exposure on sleep, cortisol, and next-day performance in Tunisian children. Thirteen participants (seven girls and six boys, age 9 ± 0.6, height 1.32 ± 0.06, weight 34.47 ± 4.41) attended six experimental nights. The experiment started with a baseline night (BL) with no smartphone exposure, followed by repeated sessions of nocturnal smartphone exposure lasting 90 minutes (08:00 pm-09:30 pm). Actigraphy; salivary cortisol; the Stroop test (selective attention); choice reaction time (CRT); N-back (working memory); counter-movement jump (CMJ), composed of flight time (time spent in the CMJ flight phase) and jump height; and a 30 m sprint were assessed the morning after each condition. Both AC and RC shortened total sleep time (TST) (p < 0.01), with a greater decrease with RC (-46.7 min, ∆% = -9.46) than AC (-28.8 min, ∆% = -5.8) compared to BL. AC and RC significantly increased waking after sleep onset (3.5 min, ∆% = 15.05, to 9.9 min, ∆% = 43.11%) and number of errors made on the Stroop test (1.8 error, ∆% = 74.23, to 3.07 error, ∆% = 97.56%). Children made 0.15 and 0.8 more errors (∆% = 6.2 to 57.61%) and spent 46.9 s and 71.6 s more time on CRT tasks (∆% = 7.22 to 11.11%) with AC and RC, respectively, compared to BL. The high-interference index of the Stroop task, CMJ performance, and 30 m sprint speed were only altered (p < 0.01) following RC (0.36, Δ% = 41.52%; -34 s, Δ% = -9.29%, for flight time and -1.23 m, -8.72%, for jump height; 0.49 s, Δ% = 6.48, respectively) when compared to BL. In conclusion, one- or five-night exposure to smartphones disturbed the children's sleep quality and their performance, with more pronounced effects following RC.

Working memory load modulates anticipatory postural adjustments during step initiation.

Working memory (WM) can influence selective attention. However, the effect of WM load on postural standing tasks has been poorly understood, even though these tasks require attentional resources. The purpose of this study was to examine whether WM load would impact anticipatory postural adjustments (APAs) during step initiation. Sixteen healthy young adults performed stepping tasks alone or concurrently with a WM task in a dual-task design. The stepping tasks involved volitional stepping movements in response to visual stimuli and comprised of simple and choice reaction time tasks and the Flanker task which consisted of congruent and incongruent (INC) conditions. In the dual-task condition, subjects were required to memorize either one or six digits before each stepping trial. Incorrect weight transfer prior to foot-lift, termed APA errors, reaction time (RT), and foot-lift time were measured from the vertical force data. The results showed that APA error rate was significantly higher when memorizing six-digit than one-digit numerals in the INC condition. In addition, RT and foot-lift time were significantly longer in the INC condition compared to the other stepping conditions, while there was no significant effect of WM load on RT or foot-lift time. These findings suggest that high WM load reduces the cognitive resources needed for selective attention and decision making during step initiation.

P3b correlates of inspection time

Both P3b and the inspection time (IT) are related with intelligence, yet the P3b correlates of IT are not well understood. This event-related potential study addressed this question by asking participants (N = 28) to perform an IT task. There were three IT conditions with different levels of discriminative stimulus duration, i.e., 33 ms, 67 ms, and 100 ms, and a control condition with no target presentation (0 ms condition). We also measured participants' processing speed with four Elementary Cognitive Tests (ECTs), including a Simple Reaction Time task (SRT), two Choice Reaction Time tasks (CRTs), and a Pattern Discrimination task (PD). Results revealed that an increase in P3b latency with longer duration of the discriminative stimulus. Moreover, the P3b latency was negatively correlated with the accuracy of the IT task in the 33 ms condition, but not evident in the 67 and 100 ms conditions. Furthermore, the P3b latency of the 33 ms condition was positively correlated with the RT of the SRT, but not related with the RTs of CRTs or PD. A significant main effect of duration on the amplitude of P1 was also found. We conclude that the present study provides the neurophysiological correlates of the IT task, and those who are able to accurately perceive and process very briefly presented stimuli have a higher speed of information process, reflected by the P3b latency, yet this relationship is more obvious in the most difficult condition. Combined, our results suggest that P3b is related with the closure of a perceptual epoch to form the neural representation of a stimulus, in support of the “context closure” hypothesis.

Viewing angle, skill level and task representativeness affect response times in basketball defence

In basketball defence, it is impossible to keep track of all players without peripheral vision. This is the first study to investigate peripheral vision usage in an experimentally controlled setup, with sport-specific basketball stimuli from a first-person perspective, large viewing eccentricities (up to 90° to the left and right), and natural action responses. A CAVE and a motion-tracking system was used to project the scenarios and capture movement responses of high- and low-skilled basketball players, respectively. Four video conditions were created: (1) a simple reaction time task without crowding (only attackers), (2) a simple reaction time task with crowding (with attackers and defenders), (3) a choice-reaction time task where the player cutting to the basket eventually passed the ball to another player and (4) a game simulation. The results indicated eccentricity effects in all tests, a crowding effect in condition 2, and expertise differences in conditions 3 and 4 only. These findings suggest that viewing eccentricity has an impact on response times, that crowding is a limiting factor for peripheral perception in sports games, and that high-skilled but not low-skilled players can compensate for eccentricity effects in real game situations, indicating their superior positioning and perceptual strategies.

Effect of Quality of Sleep on Choice Reaction Time, Coordination and Fatigue Level in Football Players

Introduction: The relationship between sleep quality and athletic performance is an important but little-researched topic in the immense world of football. This study aims to provide insight into how sleep quality affect football players’ choice reaction time, coordination, and fatigue levels, providing important information for training optimisation and improving on-field performance. Aim: To examine the effects of sleep quality on the athletic performance of young football players. Materials and Methods: A total of 40, (U-17)-developmental stage male football players who were able to perform functional keys for choice reaction time task from Chandigarh Football Association were recruited using non-probability convenience sampling. Correlational design was employed to assess sleep quality and fatigue levels using Sleep Quality Scale-(SQS) and Fatigue Assessment Scale-(FAS). Choice reaction time and coordination was determined via Deary liewald reaction time task software and Hand-eye coordination test respectively. Quantitative analysis was conducted by Karl Pearson’s coefficient correlation. Results: Study found a non significant weak positive relationship between sleep quality and choice reaction time, [r (40)=0.025, p=0.881], significant moderate positive relationship between sleep quality and coordination, [r (40)=0.433, p=0.005], and significant moderate negative relationship between sleep quality and fatigue level, [r (40)=-0.517, p=0.001]. Increased sleep quality improved coordination and reduced fatigue levels, while choice reaction time showed no significant improvements. Conclusion: Sleep quality significantly impacts coordination and fatigue levels, but no effect was observed on choice reaction time. Future research should explore various sports with a larger sample size.

Moving in response to an unseen visual stimulus

ObjectiveWhether consciousness has a causal role in voluntary movements is not clear. Backward masking blocks a stimulus from becoming conscious, but it can trigger movement in a reaction time paradigm. We hypothesize that if backward masking is used in a choice reaction time paradigm, when the visible stimulus (S2) differs from the masked stimulus (S1), the movement will often differ from conscious intent. We did such a study employing electroencephalography (EEG) to explore the brain activity associated with this effect. MethodsTwenty healthy adults participated in a choice reaction time task with a backwardly masked stimulus and EEG. They moved right or left hand in response to the direction of an arrow. S2 was congruent or incongruent with S1. When incongruent, responses were frequently concordant with S1, with faster reaction time than when responding to S2 and thought to be a mistake. ResultsWe show that it is possible to trigger movements from the unperceived stimuli indicating consciousness is not causal since the movement was not in accord with intent. EEG showed information flow from occipital cortex to motor cortex. ConclusionsOccipital activity was the same despite response, but the parietal and frontal EEG differed. When responding to S1, the motor cortex responded as soon as information arrived, and when responding to S2, the motor cortex responded with a delay allowing for other brain processing prior to movement initiation. While the exact time of conscious recognition of S2 is not clear, when there is a response to S1, the frontal cortex signals an “error”, but this is apparently too late to veto the movement. SignificanceWhile consciousness does not initiate the movement, it monitors the concordance of intent and result.

Effect of transcranial static magnetic stimulation over unilateral or bilateral motor association cortex on performance of simple and choice reaction time tasks.

Transcranial static magnetic stimulation (tSMS) is a non-invasive brain stimulation technique that place a strong neodymium magnet on scalp to reduce cortical excitability. We have recently developed a new tSMS device with three magnets placed close to each other (triple tSMS) and confirmed that this new device can produce a stronger and broader static magnetic field than the conventional single tSMS. The aim of the present study was to investigate the effect of the conventional single tSMS as well as triple tSMS over the unilateral or bilateral motor association cortex (MAC) on simple and choice reaction time (SRT and CRT) task performance. There were two experiments: one involved the conventional tSMS, and the other involved the triple tSMS. In both experiments, right-handed healthy participants received each of the following stimulations for 20 min on different days: tSMS over the unilateral (left) MAC, tSMS over the bilateral MAC, and sham stimulation. The center of the stimulation device was set at the premotor cortex. The participants performed SRT and CRT tasks before, immediately after, and 15 min after the stimulation (Pre, Post 0, and Post 15). We evaluated RT, standard deviation (SD) of RT, and accuracy (error rate). Simulation was also performed to determine the spatial distribution of magnetic field induced by tSMS over the bilateral MAC. The spatial distribution of induced magnetic field was centered around the PMd for both tSMS systems, and the magnetic field reached multiple regions of the MAC as well as the sensorimotor cortices for triple tSMS. SD of CRT was significantly larger at Post 0 as compared to Pre when triple tSMS was applied to the bilateral MAC. No significant findings were noted for the other conditions or variables. We found that single tSMS over the unilateral or bilateral MAC did not affect performance of RT tasks, whereas triple tSMS over the bilateral MAC but not over the unilateral MAC increased variability of CRT. Our finding suggests that RT task performance can be modulated using triple tSMS.

Effects of goal-setting on sustained attention and attention lapses.

In three experiments, we examined the effects of goal-setting on sustained attention and attention lapses. We measured both behavioral task performance and subjective attentional states during a four -choice reaction time task (Experiments 1 and 2 administered online; Experiment 3 conducted in-person). Experiment 1 compared a vague goal versus a specific goal. The specific goal reduced lapses in the form of long response times (RTs) but did not impact task-unrelated thoughts. Experiment 2 expanded on E1 by making the specific goal progressively harder. Behavioral lapses (i.e., long RTs) were reduced in the harder-over-time goal condition compared to the control condition. Additionally, while RTs increased with time-on-task in the control condition, RTs in the harder-over-time goal condition remained stable with time-on-task. Experiment 3 aimed to replicate the results of E2 in-person and adjusted the difficulty of the harder-over-time goals to be slightly harder. The results largely replicated E2. Overall, setting specific and difficult task goals led to a reduction in lapses of attention and increased sustained attention performance.

Cognitive Dysfunction in Patients Treated with Androgen Deprivation Therapy: A Multimodality Functional Imaging Study to Evaluate Neuroinflammation.

Androgen deprivation therapy (ADT) for prostate cancer is implicated as a possible cause of cognitive impairment (CI). CI in dementia and Alzheimer's disease is associated with neuroinflammation. In this study, we investigated a potential role of neuroinflammation in ADT-related CI. Patients with prostate cancer on ADT for ≥3 months were categorized as having ADT-emergent CI or normal cognition (NC) based on self-report at interview. Neuroinflammation was evaluated using positron emission tomography (PET) with the translocator protein (TSPO) radioligand [11C]-PBR28. [11C]-PBR28 uptake in various brain regions was quantified as standardized uptake value (SUVR, normalized to cerebellum) and related to blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) choice-reaction time task (CRT) activation maps. Eleven patients underwent PET: four with reported CI (rCI), six with reported NC (rNC), and one status unrecorded. PET did not reveal any between-group differences in SUVR regionally or globally. There was no difference between groups on brain activation to the CRT. Regardless of the reported cognitive status, there was strong correlation between PET-TSPO signal and CRT activation in the hippocampus, amygdala, and medial cortex. We found no difference in neuroinflammation measured by PET-TSPO between patients with rCI and rNC. However, we speculate that the strong correlation between TSPO uptake and BOLD-fMRI activation in brain regions involved in memory and known to have high androgen-receptor expression mediating plasticity (hippocampus and amygdala) might reflect inflammatory effects of ADT with compensatory upregulated/increased synaptic functions. Further studies of this imaging readout are warranted to investigate ADT-related CI.

Mechanisms of Training-Related Change in Processing Speed: A Drift-Diffusion Model Approach.

Processing speed is a crucial ability that changes over the course of the lifespan. Training interventions on processing speed have shown promising effects and have been associated with improved cognitive functioning. While training-related changes in processing speed are often studied using reaction times (RTs) and error rates, these measures provide limited insight into the mechanisms underlying changes during training. The drift-diffusion model provides estimates of the cognitive processes underlying speeded decision tasks, such as the rate of evidence accumulation (drift rate), response strategies (boundary separation), as well as time for other processes such as stimulus encoding and motor response (non-decision time). In the current study, we analyzed existing data of an extensive multi-session training intervention (von Bastian & Oberauer, 2013) to disentangle changes in drift rate, boundary separation, and non-decision time during training of different speeded choice-RT tasks. During this training intervention, 30 participants performed 20 training sessions over the course of four weeks, completing three tasks each session: a face-matching, a pattern-matching, and a digit-matching task. Our results show that processing speed training increased drift rates throughout training. Boundary separation and non-decision time decreased mostly during the initial parts of training. This pattern of prolonged training-related changes in rate of evidence accumulation as well as early changes in response strategy and non-decision processes was observed across all three tasks. Future research should investigate how these training-related changes relate to improvements in cognitive functioning more broadly.

Neurophysiological signatures reflect differences in visual attention during absence seizures

ObjectiveAbsences affect visual attention and eye movements variably. Here, we explore whether the dissimilarity of these symptoms during absences is reflected in differences in electroencephalographic (EEG) features, functional connectivity, and activation of the frontal eye field. MethodsPediatric patients with absences performed a computerized choice reaction time task, with simultaneous recording of EEG and eye-tracking. We quantified visual attention and eye movements with reaction times, response correctness, and EEG features. Finally, we studied brain networks involved in the generation and propagation of seizures. ResultsTen pediatric patients had absences during the measurement. Five patients had preserved eye movements (preserved group) and five patients showed disrupted eye movements (unpreserved group) during seizures. Source reconstruction showed a stronger involvement of the right frontal eye field during absences in the unpreserved group than in the preserved group (dipole fraction 1.02% and 0.34%, respectively, p < 0.05). Graph analysis revealed different connection fractions of specific channels. ConclusionsThe impairment of visual attention varies among patients with absences and is associated with differences in EEG features, network activation, and involvement of the right frontal eye field. SignificanceAssessing the visual attention of patients with absences can be usefully employed in clinical practice for tailored advice to the individual patient.