Early Time Window Research Articles

The neural dynamics of familiarity-dependent face identity representation.

Recognizing a face as belonging to a given identity is essential in our everyday life. Clearly, the correct identification of a face is only possible for familiar people, but 'familiarity' covers a wide range-from people we see every day to those we barely know. Although several studies have shown that the processing of familiar and unfamiliar faces is substantially different, little is known about how the degree of familiarity affects the neural dynamics of face identity processing. Here, we report the results of a multivariate EEG analysis, examining the representational dynamics of face identity across several familiarity levels. Participants viewed highly variable face images of 20 identities, including the participants' own face, personally familiar (PF), celebrity and unfamiliar faces. Linear discriminant classifiers were trained and tested on EEG patterns to discriminate pairs of identities of the same familiarity level. Time-resolved classification revealed that the neural representations of identity discrimination emerge around 100 ms post-stimulus onset, relatively independently of familiarity level. In contrast, identity decoding between 200 and 400 ms is determined to a large extent by familiarity: it can be recovered with higher accuracy and for a longer duration in the case of more familiar faces. In addition, we found no increased discriminability for faces of PF persons compared to those of highly familiar celebrities. One's own face benefits from processing advantages only in a relatively late time-window. Our findings provide new insights into how the brain represents face identity with various degrees of familiarity and show that the degree of familiarity modulates the available identity-specific information at a relatively early time window.

The effects of visual working memory load on detection and neural processing of task-unrelated auditory stimuli

While perceptual load has been proposed to reduce the processing of task-unrelated stimuli, theoretical arguments and empirical findings for other forms of task load are inconclusive. Here, we systematically investigated the detection and neural processing of auditory stimuli varying in stimulus intensity during a stimuli-unrelated visual working memory task alternating between low and high load. We found, depending on stimulus strength, decreased stimulus detection and reduced P3, but unaffected N1 amplitudes of the event-related potential to auditory stimuli under high as compared to low load. In contrast, load independent awareness effects were observed during both early (N1) and late (P3) time windows. Findings suggest a late neural effect of visual working memory load on auditory stimuli leading to lower probability of reported awareness of these stimuli.

Neuroimaging in Patient Selection for Thrombectomy, From the AJR Special Series on Emergency Radiology.

Endovascular thrombectomy has become the standard-of-care treatment for carefully selected patients with acute ischemic stroke due to a large-vessel occlusion of the anterior circulation. Neuroimaging plays a vital role in determining patient eligibility for thrombectomy, both in the early (0-6 hours from symptom onset) and late (> 6 to 24 hours from symptom onset) time windows. Various neuroimaging algorithms are used to determine thrombectomy eligibility, and each algorithm must be optimized for institutional workflow. In this review, we describe common imaging modalities and recommended algorithms for the evaluation of patients for endovascular thrombectomy. We also discuss emerging patient populations who might qualify for thrombectomy in the coming years.

A static paradigm based on illusion-induced VEP for brain-computer interfaces

Objective. Visual evoked potentials (VEPs) have been commonly applied in brain-computer interfaces (BCIs) due to their satisfactory classification performance recently. However, most existing methods with flickering or oscillating stimuli will induce visual fatigue under long-term training, thus restricting the implementation of VEP-based BCIs. To address this issue, a novel paradigm adopting static motion illusion based on illusion-induced visual evoked potential is proposed for BCIs to enhance visual experience and practicality. Approach. This study explored the responses to baseline and illusion tasks including the rotating-tilted-lines illusion and rotating-snakes illusion. The distinguishable features were examined between different illusions by analyzing the event-related potentials and amplitude modulation of evoked oscillatory responses. Main results. The illusion stimuli elicited VEPs in an early time window encompassing a negative component (N1) from 110 to 200 ms and a positive component (P2) between 210 and 300 ms. Based on the feature analysis, a filter bank was designed to extract discriminative signals. The task-related component analysis was used to evaluate the binary classification task performance of the proposed method. Then the highest accuracy of 86.67% was achieved with a data length of 0.6 s. Significance. The results of this study demonstrate that the static motion illusion paradigm has the feasibility of implementation and is promising for VEP-based BCI applications.

Impact of Time to Treatment on Endovascular Thrombectomy Outcomes in the Early Versus Late Treatment Time Windows.

The impact of time to treatment on outcomes of endovascular thrombectomy (EVT) especially in patients presenting after 6 hours from symptom onset is not well characterized. We studied the differences in characteristics and treatment timelines of EVT-treated patients participating in the Florida Stroke Registry and aimed to characterize the extent to which time impacts EVT outcomes in the early and late time windows. Prospectively collected data from Get With the Guidelines-Stroke hospitals participating in the Florida Stroke Registry from January 2010 to April 2020 were reviewed. Participants were EVT patients with onset-to-puncture time (OTP) of ≤24 hours and categorized into early window treated (OTP ≤6 hours) and late window treated (OTP >6 and ≤24 hours). Association between OTP and favorable discharge outcomes (independent ambulation, discharge home and to acute rehabilitation facility) as well as symptomatic intracerebral hemorrhage and in-hospital mortality were examined using multilevel-multivariable analysis with generalized estimating equations. Among 8002 EVT patients (50.9% women; median age [±SD], 71.5 [±14.5] years; 61.7% White, 17.5% Black, and 21% Hispanic), 34.2% were treated in the late time window. Among all EVT patients, 32.4% were discharged home, 23.5% to rehabilitation facility, 33.7% ambulated independently at discharge, 5.1% had symptomatic intracerebral hemorrhage, and 9.2% died. As compared with the early window, treatment in the late window was associated with lower odds of independent ambulation (odds ratio [OR], 0.78 [0.67-0.90]) and discharge home (OR, 0.71 [0.63-0.80]). For every 60-minute increase in OTP, the odds of independent ambulation reduced by 8% (OR, 0.92 [0.87-0.97]; P<0.001) and 1% (OR, 0.99 [0.97-1.02]; P=0.5) and the odds of discharged home reduced by 10% (OR, 0.90 [0.87-0.93]; P<0.001) and 2% (OR, 0.98 [0.97-1.00]; P=0.11) in the early and late windows, respectively. In routine practice, just over one-third of EVT-treated patients independently ambulate at discharge and only half are discharged to home/rehabilitation facility. Increased time from symptom onset to treatment is significantly associated with lower chance of independent ambulation and ability to be discharged home after EVT in the early time window.

Smaller baseline subcortical infarct volume predicts good outcomes in patients with a large core in early acute ischemic stroke after endovascular treatment.

Patients with acute ischemic stroke (AIS) and a large core may benefit from endovascular treatment (EVT) in the early time window. To examine the prognostic factors for good outcomes in patients with a large core (70-130 ml) after EVT. We retrospectively reviewed 40 patients who met the criteria from October 2019 to April 2021. Based on the modified Rankin Score (mRS) at 90 days, the patients were divided into a good outcome group (mRS 0-2) and a poor outcome group (mRS 3-6). Baseline and procedural characteristics were collected for unilateral and multivariate regression analyses to explore the factors that influence good outcomes. In particular, the infarct territories were quantified as subcortical infarct volume (SIV) and cortical infarct volume (CIV). Of the 40 patients included, good outcomes were observed in 11 (27.5%) patients. Younger age, smaller SIV and larger mismatch volume were noted in the good outcome group than in the poor outcome group (all P < 0.05). Multivariate logistic regression analysis showed that only a smaller SIV [odds ratio (OR) 0.801; 95% CI 0.644-0.996; P = 0.046] was an independent predictor for good outcomes. The receiver operating characteristic curve indicated a moderate value of SIV for predicting good outcomes, with an area under the receiver operating characteristic curve of 0.735 (95% CI 0.572-0.862; P = 0.007). Subcortical infarct volume was a potential useful predictor of good outcomes in patients with a large core after EVT in the early time window.

Impaired proactive control in individuals with methamphetamine use disorder: Evidence from ERPs

BackgroundResearch suggests that methamphetamine use is associated with impaired cognitive control, which may contribute to impulsive drug use. Cognitive control is dynamically mediated by proactive and reactive control (reflecting various processing stages of cognitive control with different properties), and it is crucial to determine whether methamphetamine use impairs proactive and/or reactive control. To address this issue, we conducted an event-related potential (ERP) study to examine proactive and reactive control in individuals with methamphetamine use disorder (MUD). MethodsAbstinent individuals with MUD (n = 25) and healthy controls (HC, n = 27) completed a cued task-switching task while brain electrical activity was recorded. Cue- and target-locked ERP components modulated by task switching were linked to proactive and reactive control, respectively. ResultsNo behavioral differences between the groups were found. However, the HC group showed cue-locked switch-positivity (i.e., more positive amplitudes for switch than repeat trials) in both the early and late time windows, although the MUD group only showed late switch-positivity, which was smaller than the HC group. Independent of switch or congruent condition, the MUD group had smaller target-locked positivity than the HC group. ConclusionsThese findings suggest that individuals with MUD exhibit reduced proactive control and mobilize extra reactive control efforts to compensate. Our study contributes to a better understanding of cognitive control impairment in individuals with MUD and has implications for potential interventions.

Abstract WMP92: Presentation Blood Glucose Is Associated With CTP Core Volume Overestimations In Acute Ischemic Stroke Patients With Large Vessel Occlusion

Background: CT Perfusion (CTP) predictions of infarct core play a large role in determination of treatment eligibility in large vessel occlusion (LVO) acute ischemic stroke (AIS). Prior studies have demonstrated that glucose can affect cerebral blood flow (CBF). Here we evaluate the influence of acute and chronic glucose levels on CTP over-estimation (OE) of infract core, leading to potential undertreatment. Methods: From our prospectively collected multicenter observational cohort, we identified AIS LVO patients evaluated with non-contrast CT, CTA and concurrent CTP who underwent endovascular therapy with substantial reperfusion (TICI2b-3), and also had MRI 48-72 hours post-treatment. OE was defined as a difference of at least 20 mL between CTP-RAPID (IschemaView, Stanford CA) predicted infarct core and DWI final infarct volume (FIV). The primary outcome was the association of glucose and HgbA1c on OE and was measured using multivariable logistic regression to control for other patient level factors. Results: Among 256 patients meeting inclusion criteria, median age was 67 [IQR 57-77] and 51.6% were female. Median CTP-predicted core was 6 mL [IQR 0-30], median DWI FIV was 14 mL [IQR 6-43] with median difference of 12 mL [IQR 5-35]. 28 patients (10.9%) had OE, with median difference in infarct size of 40 mL [24-56]. In univariable analysis, early time window (&lt;6 hours from last known well), absence of diabetes, normal HgbA1c, and normal admission glucose were associated with OE. In multivariate analysis, early time window (aOR 2.87, p=0.025) and lower/normal glucose (aOR 3.01, p=0.02) were independent predictors of OE. Among 65 patients with higher HgbA1c and blood glucose levels (&gt;6.5, &gt;126), 27 patients (42%) had CTP core under-estimation (UE). Conclusions: Acute and chronic changes in glycemic state affect automated CTP interpretations. These findings may be related to previously described effects on cerebral blood flow.

Abstract TP98: Deep Learning-based Automatic Ischemic Core Estimation Based On Non-contrastenhanced Computed Tomography

Background/Purpose: With the spread of thrombus retrieval procedures, the demand for immediate diagnosis and severity assessment of ischemic stroke is increasing, but current standard method using ASPECTS is semi-quantitative, and has low consistency among physicians. We develop and validate the fully automatic machine learning-based ischemic core segmentation model based only on non-contrast-enhanced computed tomography (NCCT). Materials and Methods: This multicenter retrospective study included patients with anterior circulation acute ischemic stroke who received both CT and MRI before thrombolysis or recanalization treatment between 2013 to 2019. The ischemic core on CT was manually delineated referencing the DWI and ADC map. A deep learning-based ischemic core segmentation model was developed using the derivation cohort data from 3 institutions (n=313), and the model performance was validated on the external validation cohort data from 3 institutions (n=106). Results: On the validation cohort, the median time between CT and MRI was 18 min. The ischemic core volume calculated by the DL model was significantly correlated with the reference standard (Pearson r=0.91, p&lt;.001). The correlation was significant both in early time window (&lt;4.5hr from onset; Pearson r=0.91, p&lt;.0.01) and the late time window (&gt;4.5hr from onset; Pearson r=0.93, p&lt;0.01). The median difference between model and reference standard was 4.7 mL (IQR, 0.8-12.4 mL). The DL model displayed high accuracy on discriminating large ischemic core (&gt;70mL) with a sensitivity of 84.2%, specificity of 97.7%, and AUC of 0.91. Conclusions: A segmentation model of cerebral ischemic core volume of the anterior circulation based on NCCT using deep learning showed good correlation with the correct labels generated with reference to MRI.

Abstract 69: Blood-brain Barrier Profile Influences Outcome After Mechanical Thrombectomy In The Frame Study.

Background and Purpose: The FRAME study demonstrated that even in the early time window (&lt;6hrs) perfusion imaging profiles can influence response to mechanical thrombectomy. Perfusion imaging (PWI) can also be used to measure damage to the blood-brain barrier (BBB) which has been shown to be associated with increased risk of hemorrhagic complications (HC) with treatment. We aimed to determine if BBB profiles in the FRAME study would influence outcome after mechanical thrombectomy (MT). Methods: This was a post-hoc analysis of the FRAME study which enrolled stroke patients with large vessel occlusion who received MT within 6 hours of stroke onset. Patients with successful pre-treatment MRI PWI were included. We tested the hypothesis that more severe pre-treatment BBB disruption is associated with higher frequency of HC after MT. BBB disruption was measured as the percent of signal change due to gadolinium leakage on the PWI source images. Mean permeability derangement (MPD) was defined as the average of all voxels in the stroke core that are two standard deviations above normal. The outcome of HC was defined as any type of parenchymal hematoma (PH1 or PH2); poor functional outcome was defined as mRS &gt;2 at 90 days. MPD was compared with HC and functional outcome using the Wilcoxon signed-rank test and logistic regression. A prespecified MPD threshold of 20% was tested as a predictor of HC based on prior studies. Results: There were 164 patients included in the analysis, median age 74 and 48% female. HC occurred in 57 patients. The average MPD was 15.1% for patients with HC and 8.7% for patients without HC. Elevated MPD was significantly associated with HC (p&lt;0.0001) with a 25% increased risk of HC for each 5% increase in MPD (OR 1.25; CI 1.09:1.45; p=0.0018). Increased MPD was also associated with poor functional outcome (p=0.0002). ROC analysis confirmed the prespecified MPD threshold, identifying 19.7% as the optimal cut point for classification. MPD greater than 20% more than tripled the risk of HC (OR 3.37; CI 1.49:7.85; p=0.004). Conclusions: Increased pre-treatment BBB disruption has a substantial influence on the risk of HC after MT. Integration of BBB imaging into patient selection algorithms to improve MT outcomes should be tested further.

Abstract WP115: DWI/FLAIR Mismatch Is Common In Late Window Patients With Target Perfusion Mismatch

Introduction: The presence of a DWI/FLAIR mismatch has been suggested as a method to identify patients within 4.5 hours from stroke symptom onset. We studied patients from DEFUSE 2 and 3 with the target perfusion mismatch profile to evaluate the rates of DWI/FLAIR mismatch in patients with who have favorable collaterals in early and late time windows. We hypothesize that the persistence of DWI/FLAIR mismatch in late window patients may reflect good collateral circulation. Methods: We identified 58 eligible patients in D2 and 30 patients from D3. Imaging was reviewed by two neuroradiologists and one neurologist who rated the presence of DWI-FLAIR mismatch. Results: The inter-rater agreement for the presence of DWI/FLAIR mismatch was 88.3%. There were 32 patients who were &lt; 6 hours from last known well (LKW) or symptom onset, 17 patients who were ≥ 6 hours from symptom onset, and 26 patients who were ≥ 6 hours from LKW with an unknown time of symptom onset. These are categorized as early, late, and suspected late window, respectively. The rate of DWI/FLAIR mismatch was 56% in the early window group, 41% in the late window group, and 35% in the suspected late window group. The overall rate of DWI/FLAIR mismatch did not differ significantly between these three groups (56% vs. 41% vs. 35%, p=0.239). Of the early window patients, the rate of DWI-FLAIR mismatch was higher in those with the target perfusion mismatch profile (67%) compared to those without (36%). All but one the known onset late window patients had the target perfusion mismatch profile, and the rate of DWI-FLAIR mismatch in this group was 35%. Forthcoming analyses will include predictors of DWI-FLAIR mismatch such as hypoperfusion intensity ratio, time from symptom onset, and NIHSS score. Conclusions: More than one-third of patients presenting &gt;6 hours from symptom onset with a target perfusion mismatch profile have DWI/FLAIR mismatch. This could reflect the presence of good collateral circulation that may delay the appearance of a FLAIR lesion. The rate of DWI/FLAIR mismatch did not differ among early, late, and expected late window patients. This suggests that, among patients with favorable collaterals, DWI/FLAIR mismatch does not reliably identify early window patients.

Predictive value of computed tomography perfusion for acute ischemic stroke patients with ASPECTS < 6 in an early time window

ObjectiveThe standard for computed tomography perfusion (CTP) assessment has not been well established in early acute ischemic stroke (AIS). We aimed to examine the prognostic factors for good outcomes in patients who received CTP, with an Alberta Stroke Program Early CT Score (ASPECTS) < 6 after endovascular thrombectomy (EVT) in the early time window (0–6 h). MethodsWe retrospectively reviewed 59 patients who met the criteria from October 2019 to April 2021. Based on the modified Rankin Score (mRS) at 90 days, the patients were divided into a good outcome group (mRS 0–2) and a poor outcome group (mRS 3–6). Baseline and procedural characteristics were collected for unilateral and multivariate regression analyses to explore the influencing factors for good outcomes. ResultsOf the 59 patients included, good outcomes were observed in 21 (35.6%). Multivariate logistic regression analysis showed that smaller ischemic core volume (odds ratio [OR]: 0.950; 95% CI: 0.908–0.994; P = 0.026), lower National Institutes of Health Stroke Scale (NIHSS) score (OR: 0.750; 95% CI: 0.593–0.949; P = 0.017) and shorter stroke onset to reperfusion time (ORT) (OR: 0.981; 95% CI: 0.966–0.996; P = 0.016) were independent predictors for good outcomes at 90 days. ConclusionSmaller ischemic core volume based on CTP, lower NIHSS score and shorter ORT were significant independent predictors of good outcomes in patients with ASPECTS < 6 in the early time window after EVT.

Plasticity Changes in Central Auditory Systems of School-Age Children Following a Brief Training With a Remote Microphone System.

The objective of this study was to investigate whether a brief speech-in-noise training with a remote microphone (RM) system (favorable listening condition) would contribute to enhanced post-training plasticity changes in the auditory system of school-age children. Before training, event-related potentials (ERPs) were recorded from 49 typically developing children, who actively identified two syllables in quiet and in noise (+5 dB signal-to-noise ratio [SNR]). During training, children completed the same syllable identification task as in the pre-training noise condition, but received feedback on their performance. Following random assignment, half of the sample used an RM system during training (experimental group), while the other half did not (control group). That is, during training' children in the experimental group listened to a more favorable speech signal (+15 dB SNR) than children from the control group (+5 dB SNR). ERPs were collected after training at +5 dB SNR to evaluate the effects of training with and without the RM system. Electrical neuroimaging analyses quantified the effects of training in each group on ERP global field power (GFP) and topography, indexing response strength and network changes, respectively. Behavioral speech-perception-in-noise skills of children were also evaluated and compared before and after training. We hypothesized that training with the RM system (experimental group) would lead to greater enhancement of GFP and greater topographical changes post-training than training without the RM system (control group). We also expected greater behavioral improvement on the speech-perception-in-noise task when training with than without the RM system. GFP was enhanced after training only in the experimental group. These effects were observed on early time-windows corresponding to traditional P1-N1 (100 to 200 msec) and P2-N2 (200 to 400 msec) ERP components. No training effects were observed on response topography. Finally, both groups increased their speech-perception-in-noise skills post-training. Enhanced GFP after training with the RM system indicates plasticity changes in the neural representation of sound resulting from listening to an enriched auditory signal. Further investigation of longer training or auditory experiences with favorable listening conditions is needed to determine if that results in long-term speech-perception-in-noise benefits.

Frequency of Thrombectomy in Early and Late Postonset Time Windows Among Emergency Medical Services Patients With Acute Ischemic Stroke

Background With recent trials demonstrating benefit of endovascular thrombectomy (EVT) up to 24 hours from last known well time (LKWT), emergency medical services systems must consider stroke center routing for patients with LKWT ≤24 hours. We sought to determine the frequency of thrombectomy by prehospital‐determined LKWT using retrospective data from a tiered regional stroke care system. Methods During the July 2018 to March 2019 study period, patients with potential large‐vessel occlusion, based on a Los Angeles Motor Scale of 4 or 5, were routed directly to a designated EVT center if within 30 minutes. We determined the frequency of thrombectomy by time intervals from prehospital‐determined LKWT to first medical contact. Results Emergency medical services transported 830 patients with acute ischemic stroke with documented prehospital‐determined LKWT ≤24 hours to EVT centers. The ≤6 hours, &gt;6 to ≤16 hours, and &gt;16 to ≤24 hours epochs accounted for 75%, 20%, and 5% of transports to EVT centers, respectively. Men accounted for 47% of the study population, with a median age of 77 years (interquartile range, 64–86 years) and National Institutes of Health Stroke Scale median of 11 (interquartile range, 4–20). Overall, 28.2% (234/830) received EVT. Time window–specific EVT frequencies were: ≤6 hours (29.8% of patients [187/627]); &gt;6 to ≤16 hours (24.1% of patients [39/162]); and &gt;16 to ≤24 hours (19.5% of [8/41]). Conclusion In this regional stroke system with 2‐tiered routing, patients in the &gt;6‐ to 24‐hour postonset window accounted for nearly one fourth of transports to EVT centers and 23% received thrombectomy.

Mechanical thrombectomy for large vessel occlusion strokes beyond 24 hours

BackgroundRecent clinical trials have shown that mechanical thrombectomy is superior to medical management for large vessel occlusion for up to 24 hours from onset. Our objective is to examine the...

The default-interventionist model underlies premise typicality weakening the premise diversity effect during category-based induction: Event-related potentials evidence.

The diversity effect during category-based induction (CBI) means that the more diverse the evidence, the higher will be the conclusion's inductive strength. However, it is influenced by the premise typicality. Three competitive cognitive processing models account for this influence: (1) The pre-emptive conflict resolution model assumes that only premise typicality activates; (2) the parallel-competitive model assumes that premise typicality and diversity activate in parallel; and (3) the default-interventionist model assumes that a default response of premise diversity first activates and is subsequently followed by premise typicality, or premise typicality activates first, followed by premise diversity. The timing of premise typicality affecting the diversity effect during CBI was measured using event-related potentials to determine which cognitive model best explains this influence. Similar to previous studies, non-diverse premise inductive tasks involving two typical premise categories were compared with diverse premise inductive tasks involving a typical and an atypical category. The results showed that non-diverse conditions had higher "correct" response proportions, greater inductive strength, higher "definitely" response proportions, and shorter reaction times than diverse conditions, showing that premise typicality weakens the diversity effect. Moreover, the diverse premises elicited larger P2, smaller FN400, and greater frontal post-N400-positivity amplitudes than non-diverse premises, suggesting that premise diversity was facilitated during a relatively early time window and revised by premise typicality in a later window. These results support the default-interventionist in nature during thinking and reasoning.

Neurocognitive Dynamics of Prosodic Salience over Semantics during Explicit and Implicit Processing of Basic Emotions in Spoken Words.

How language mediates emotional perception and experience is poorly understood. The present event-related potential (ERP) study examined the explicit and implicit processing of emotional speech to differentiate the relative influences of communication channel, emotion category and task type in the prosodic salience effect. Thirty participants (15 women) were presented with spoken words denoting happiness, sadness and neutrality in either the prosodic or semantic channel. They were asked to judge the emotional content (explicit task) and speakers' gender (implicit task) of the stimuli. Results indicated that emotional prosody (relative to semantics) triggered larger N100, P200 and N400 amplitudes with greater delta, theta and alpha inter-trial phase coherence (ITPC) and event-related spectral perturbation (ERSP) values in the corresponding early time windows, and continued to produce larger LPC amplitudes and faster responses during late stages of higher-order cognitive processing. The relative salience of prosodic and semantics was modulated by emotion and task, though such modulatory effects varied across different processing stages. The prosodic salience effect was reduced for sadness processing and in the implicit task during early auditory processing and decision-making but reduced for happiness processing in the explicit task during conscious emotion processing. Additionally, across-trial synchronization of delta, theta and alpha bands predicted the ERP components with higher ITPC and ERSP values significantly associated with stronger N100, P200, N400 and LPC enhancement. These findings reveal the neurocognitive dynamics of emotional speech processing with prosodic salience tied to stage-dependent emotion- and task-specific effects, which can reveal insights into understanding language and emotion processing from cross-linguistic/cultural and clinical perspectives.

Offline rTMS inhibition of the right dorsolateral prefrontal cortex impairs reappraisal efficacy.

In this study we verified the causal role of the bilateral dorsolateral prefrontal cortex (DLPFC) in emotional regulation using a strategy of reappraisal, which involves intentionally changing the meaning of an affective event to reduce its emotional impact. Healthy participants (n = 26; mean age = 25.4) underwent three sessions of inhibitory continuous theta burst stimulation (cTBS) applied on three different days over the left or right DLPFC, or the vertex. After applying the stimulation protocol participants were presented with neutral and negative pictorial stimuli that had to be either passively watched or reappraised. The efficacy of emotional control was quantified using the Late Positive Potential (LPP), the neural marker of motivated attention and elaborated stimulus processing. The results showed that reappraisal was compromised after inhibitory stimulation of the right DLPFC compared to the vertex. This impairment of affective modulation was reflected in both early (350-750ms) and late (750-1500ms) time windows. As no session differences during the passive watching conditions were found, the decrease in reappraisal efficacy due to non-specific changes in basic perceptual processing was considered unlikely. Instead, we suggest that inhibition of the right DLPFC primarily affects the top-down mechanism of attentional deployment. This results in disturbances of attentional processes that are necessary to thoroughly elaborate the content of affective stimuli to enable their new, less negative interpretation.

Impact of collateral flow on cost-effectiveness of endovascular thrombectomy.

Acute ischemic stroke patients with large-vessel occlusion and good collateral blood flow have significantly better outcomes than patients with poor collateral circulation. The purpose of this study was to evaluate the cost-effectiveness of endovascular thrombectomy (EVT) based on collateral status and, in particular, to analyze its effectiveness in ischemic stroke patients with poor collaterals. A decision analysis study was performed with Markov modeling to estimate the lifetime quality-adjusted life-years (QALYs) and associated costs of EVT based on collateral status. The study was performed over a lifetime horizon with a societal perspective in the US setting. Base-case analysis was done for good, intermediate, and poor collateral status. One-way, two-way, and probabilistic sensitivity analyses were performed. EVT resulted in greater effectiveness of treatment compared to no EVT/medical therapy (2.56 QALYs in patients with good collaterals, 1.88 QALYs in those with intermediate collaterals, and 1.79 QALYs in patients with poor collaterals), which was equivalent to 1050, 771, and 734 days, respectively, in a health state characterized by a modified Rankin Scale (mRS) score of 0-2. EVT also resulted in lower costs in patients with good and intermediate collaterals. For patients with poor collateral status, the EVT strategy had higher effectiveness and higher costs, with an incremental cost-effectiveness ratio (ICER) of $44,326/QALY. EVT was more cost-effective as long as it had better outcomes in absolute numbers in at least 4%-8% more patients than medical management. EVT treatment in the early time window for good outcome after ischemic stroke is cost-effective irrespective of the quality of collateral circulation, and patients should not be excluded from thrombectomy solely on the basis of collateral status. Despite relatively lower benefits of EVT in patients with poor collaterals, even smaller differences in better outcomes have significant long-term financial implications that make EVT cost-effective.

Crop type mapping using time-series Sentinel-2 imagery and U-Net in early growth periods in the Hetao irrigation district in China

The information on spatial distribution pattern and area of different crops is particularly useful for monitoring and managing the sustainability of agricultural resources. However, there are still challenges in timely mapping of crop types and planting areas to support production during the present growing season. Here, we proposed to use time-series Sentinel-2 imagery and a deep learning method for major crop mapping (wheat, maize, sunflower, and squash) in the agricultural production areas in the Hetao Irrigation District (HID), Inner Mongolia Autonomous Region, China. A feature selection method that combines the global separability index and feature recursive elimination was proposed to optimize the band features of Sentinel-2 imagery. The Random Forest, Extreme Gradient Boosting, U-Net and deeplabv3+ algorithms were then used for image classification with all spectral bands and the selected band features, respectively. The selected bands and best method were used to determine the key time window for the early identification of four major crops. Integrate all image datasets in the early window period, and build mapping models suitable for images at different times in the window period by combining the selected bands and best method. The results showed that the proposed feature selection method effectively removed redundant features and improved the classification efficiency. The U-Net algorithm was more suitable for the classification of major crops in HID with a higher accuracy whether using all band features or the selected features. The key periods for early recognition of wheat, maize, sunflower, and squash in HID were mid-May, late June, early July, and late June, respectively. The constructed models for crop type mapping in the early period were tested in 2020 and 2021 in the HID, and the F1-score, the mean intersection-over-union and overall accuracy were 86.71 %, 84.66 %, and 98.89 %, respectively. The proposed feature selection method, U-Net classification algorithm, and screening of the early mapping window period in this study provide an efficient, accurate and timely crop mapping tool in HID. Future research can further verify the applicability of the early identification time window proposed in this study to support other agricultural management activities in the areas.