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1.
J Vis ; 24(5): 12, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38787569

ABSTRACT

Materials exhibit an extraordinary range of visual appearances. Characterizing and quantifying appearance is important not only for basic research on perceptual mechanisms but also for computer graphics and a wide range of industrial applications. Although methods exist for capturing and representing the optical properties of materials and how they vary across surfaces (Haindl & Filip, 2013), the representations are typically very high-dimensional, and how these representations relate to subjective perceptual impressions of material appearance remains poorly understood. Here, we used a data-driven approach to characterizing the perceived appearance characteristics of 30 samples of wood veneer using a "visual fingerprint" that describes each sample as a multidimensional feature vector, with each dimension capturing a different aspect of the appearance. Fifty-six crowd-sourced participants viewed triplets of movies depicting different wood samples as the sample rotated. Their task was to report which of the two match samples was subjectively most similar to the test sample. In another online experiment, 45 participants rated 10 wood-related appearance characteristics for each of the samples. The results reveal a consistent embedding of the samples across both experiments and a set of nine perceptual dimensions capturing aspects including the roughness, directionality, and spatial scale of the surface patterns. We also showed that a weighted linear combination of 11 image statistics, inspired by the rating characteristics, predicts perceptual dimensions well.


Subject(s)
Wood , Humans , Female , Adult , Male , Young Adult , Surface Properties , Photic Stimulation/methods , Form Perception/physiology , Pattern Recognition, Visual/physiology
2.
Article in English | MEDLINE | ID: mdl-38445394

ABSTRACT

BACKGROUND AND AIMS: A significant source of man-made radiation is now linked to medical devices especially X-ray imaging based ones like CT scans which expose the body to cumulative ionizing radiation and thus attendant cancer risks. The aim of this study was to determine whether using a combination of Automatic Tube Current Modulation (ATCM) and Automatic Tube Voltage Selection (ATVS) during two-phase whole-body CT (2PWBCT) examinations would reduce the radiation dose while preserving the image quality. PATIENTS AND METHODS: This was a prospective, observational, single-centre study of 127 adult patients who had undergone the 2PWBCT polytraumatic protocol. All were examined on a Somatom Drive scanner (Siemens). The patients were divided into two groups: ATCM only (42 patients) and ATCM +ATVS (85 patients). Patients' arm positions during examination and the examination dose length product (DLP) values were recorded, as well the standard deviations (SD) of the density in reference areas on CT scans for the image quality assessment. The DLP values and image quality in the groups were compared using ANOVA. RESULTS: Mean Total DLP (in mGy*cm): ATCM only: 3337 +/-797, ATCM+ATVS: 3402 +/-830; P=0.674. No effect of arm position (P=0.586). Mean density SD values in reference areas (in HU) in ATCM only: 49 +/-45, 15 +/-6, 9 +/-2, 12 +/-4, 10 +/-3, in ATCM+ATVS: 48 +/-45, 17 +/-6, 11 +/-3, 15 +/-6, 12 +/-4. SD values was higher in ATCM+ATVS group (P<0.001). CONCLUSION: Combination of ATVS and ATCM in polytraumatic 2PWBCT leads to no significant radiation load reduction compared with ATCM only but does lead to a slight degradation of image quality. The radiation load is significantly reduced if the patient has their arms behind the head when scanning, regardless of the activation of ATVS.

3.
Psychon Bull Rev ; 2023 Nov 08.
Article in English | MEDLINE | ID: mdl-37940799

ABSTRACT

In dynamic environments, a central task of the attentional system is to keep track of objects changing their spatial location over time. In some instances, it is sufficient to track only the spatial locations of moving objects (i.e., multiple object tracking; MOT). In other instances, however, it is also important to maintain distinct identities of moving objects (i.e., multiple identity tracking; MIT). Despite previous research, it is not clear whether MOT and MIT performance emerge from the same tracking mechanism. In the present report, we study gaze coherence (i.e., the extent to which participants repeat their gaze behaviour when tracking the same object locations twice) across repeated MOT and MIT trials. We observed more substantial gaze coherence in repeated MOT trials compared to the repeated MIT trials or mixed MOT-MIT trial pairs. A subsequent simulation study suggests that MOT is based more on a grouping mechanism than MIT, whereas MIT is based more on a target-jumping mechanism than MOT. It thus appears unlikely that MOT and MIT emerge from the same basic tracking mechanism.

4.
Quant Imaging Med Surg ; 13(9): 5770-5782, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37711771

ABSTRACT

Background: The prospective study assessed infarct growth rate (IGR) in acute ischemic stroke (AIS) with large vessel occlusion (LVO) after recanalization in early time window. Early IGR (EIGR) and late IGR (LIGR) were correlated with imaging and clinical data; we searched for outcome predictors. Methods: We included 71 consecutive patients. Subjects underwent computed tomography perfusion (CTP) for ischemic core volume assessment at 99.0 minutes (median) from stroke onset, recanalization was performed at 78.0 minutes (median) from CTP. Final infarct volume (FIV) was measured on 24±2 hours imaging follow-up. EIGR was calculated as the core volume/time between stroke onset and CTP; LIGR was calculated as FIV/time between CTP and imaging follow-up. Twenty-two subjects were assessed as poor outcome, 49 as good outcome. Group differences were tested by Mann-Whitney test and χ2 test. Bayesian logistic regression models were used to predict clinical outcome, Pearson correlations for the log-transformed predictors. Results: Subjects with poor outcome were older, median age 78.0 [interquartile range (IQR): 71.8, 83.8] versus 68.0 (IQR: 57.0, 73.0) years; 95% confidence interval (CI): 6.00 to 16.00; P<0.001. Their stroke severity scale was higher, median 19.0 (IQR: 16.0, 20.0) versus 15.5 (IQR: 10.8, 18.0); 95% CI: 1.00 to 6.00; P<0.001. They had higher EIGR, median 23.9 (IQR: 6.4, 104.0) versus 6.7 (IQR: 1.7, 13.0) mL/h; 95% CI: 3.26 to 53.68; P=0.002; and larger core, median 52.5 (IQR: 13.1, 148.5) versus 10.0 (IQR: 1.4, 20.0) mL; 95% CI: 11.00 to 81.00; P<0.001. In subjects with poor outcome, infarct growth continued after thrombectomy with LIGR 2.0 (IQR: 1.2, 9.7) versus 0.3 (IQR: 0.0, 0.7) mL/h; 95% CI: 1.10 to 6.10; P<0.001; resulting in larger FIV, median 186.5 (IQR: 49.3, 280.8) versus 18.5 (IQR: 8.0, 34.0) mL; 95% CI: 55.30 to 214.00; P<0.001. Strong correlations among predictors were found e.g., core and EIGR (r=0.942), LIGR and FIV (r=0.779), core and FIV (r=0.761). Clinical outcome was best predicted using data from later measurements as FIV and LIGR. Conclusions: Data from later measurements were more predictive, there was no major benefit to use growth over volume data.

5.
Q J Exp Psychol (Hove) ; 76(9): 2094-2106, 2023 Sep.
Article in English | MEDLINE | ID: mdl-36398964

ABSTRACT

In everyday life, we often view objects through a limited aperture (e.g., soccer players on TV or cars slipping into our blind spot on a busy road), where objects often move out of view and reappear in a different place later. We modelled this situation in a series of multiple object tracking (MOT) experiments, in which we introduced a cover on the edges of the observed area and manipulated its width. This method introduced systematic occlusions, which were longer than those used in previous MOT studies. Experiment 1 (N = 50) showed that tracking under such conditions is possible, although difficult. An item-level analysis confirmed that people made more errors in targets that were covered longer and more often. In Experiment 2 (N = 50), we manipulated the tracking workload and found that the participants were less affected by the cover when the tracking load was low. In Experiment 3 (N = 50), we asked the participants to keep track of the objects' identities (multiple identity tracking [MIT]). Although MIT is subjectively more demanding, memorising identities improved performance in the most difficult cover conditions. Contrary to previous reports, we also found that even partial occlusions negatively affected tracking.


Subject(s)
Attention , Motion Perception , Humans
6.
Graefes Arch Clin Exp Ophthalmol ; 261(1): 263-272, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35982247

ABSTRACT

INTRODUCTION: The objective of this prospective study was to evaluate the effects of intraocular macular lens implantation and visual rehabilitation on the quality of life of patients with geographic atrophy (GA) secondary to age-related macular degeneration (AMD). METHODS: Patients with bilaterally decreased near vision (not better than 0.3 logMAR with the best correction), pseudophakia, were included in the project. The Scharioth macula lens (SML) was implanted into the patients' better-seeing eye. Intensive visual rehabilitation of the ability to perform nearby activities was performed for 20 consecutive postoperative days. All subjects were examined before and after SML implantation ophthalmologically. The National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ-25) was administered before and 6 months after surgery. RESULTS: Twenty eligible patients with mean age 81 years (63 to 92 years) were included in the project: 7 males and 13 females. Nineteen of them completed the 6-month follow-up. Near uncorrected visual acuity was 1.321 ± 0.208 logMAR before SML implantation and improved to 0.547 ± 0.210 logMAR after 6 months (dz = - 2.846, p < 0.001, BF10 = 3.29E + 07). In the composite score of the NEI VFQ-25, there was an improvement in the general score and the specific domains related to the implantation. Participants reported fewer difficulties in performing near activities (dz = 0.91, p = 0.001, BF10 = 39.718) and upturns in mental health symptoms related to vision (dz = 0.62, p = .014, BF10 = 3.937). CONCLUSION: SML implantation, followed by appropriate rehabilitation, improved near vision and increased the quality of life of visually handicapped patients with AMD in our project.


Subject(s)
Geographic Atrophy , Lenses, Intraocular , Macular Degeneration , Male , Female , Humans , Aged , Aged, 80 and over , Quality of Life , Geographic Atrophy/diagnosis , Geographic Atrophy/etiology , Prospective Studies , Macular Degeneration/complications , Macular Degeneration/diagnosis , Surveys and Questionnaires
7.
Diagnostics (Basel) ; 12(10)2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36291979

ABSTRACT

CT perfusion (CTP) is used for the evaluation of brain tissue viability in patients with acute ischemic stroke (AIS). We studied the accuracy of three different syngo.via software (SW) settings for acute ischemic core estimation in predicting the final infarct volume (FIV). The ischemic core was defined as follows: Setting A: an area with cerebral blood flow (CBF) < 30% compared to the contralateral healthy hemisphere. Setting B: CBF < 20% compared to contralateral hemisphere. Setting C: area of cerebral blood volume (CBV) < 1.2 mL/100 mL. We studied 47 AIS patients (aged 68 ± 11.2 years) with large vessel occlusion in the anterior circulation, treated in the early time window (up to 6 h), who underwent technically successful endovascular thrombectomy (EVT). FIV was measured on MRI performed 24 ± 2 h after EVT. In general, all three settings correlated with each other; however, the absolute agreement between acute ischemic core volume on CTP and FIV on MRI was poor; intraclass correlation for all three settings was between 0.64 and 0.69, root mean square error of the individual observations was between 58.9 and 66.0. Our results suggest that using CTP syngo.via SW for prediction of FIV in AIS patients in the early time window is not appropriate.

8.
Addict Behav ; 135: 107423, 2022 12.
Article in English | MEDLINE | ID: mdl-35933287

ABSTRACT

Problematic internet use (PIU) has adverse effects on adolescent health. Parenting may play an important role in the prevention of this condition, but the associations between PIU and parental behavior are unknown. This meta-analysis examined the associations between adolescent PIU and general and media-specific parenting. Studies were obtained using searches in scientific databases and using references identified from bibliographies. Searches covered English written journal articles, master's theses, and doctoral dissertations from the year each database started until April 2022. Studies were included if they (a) measured PIU, (b) measured parenting, (c) used data obtained from children or adolescents, and (d) reported a valid analysis. Two coders decided whether each study met the required criteria. Data were pooled using a random effects model. We found weak negative associations between PIU and general parenting, namely, warmth (r = -0.17, [-0.13, -0.20], k = 24; N = 58401), control (r = -0.10, [-0.01, -0.18], k = 10, N = 12199), and authoritative parenting (r = -0.12, [-0.02, -0.21], k = 8, N = 5431), but the associations between PIU and media-specific parenting, namely, active mediation (r = -0.02, [-0.07, 0.02], k = 11, N = 30545) and restrictive mediation (r = 0.01, [-0.10, 0.11], k = 16, N = 36997), were non-significant. In older adolescents, the association between restrictive mediation and PIU was significant but positive. Media parenting has only weak association with PIU and thus restrictions should be used cautiously, especially in older adolescents. Additional prospective studies on parenting and specific PIU activities are needed.


Subject(s)
Adolescent Behavior , Behavior, Addictive , Adolescent , Behavior, Addictive/epidemiology , Child , Humans , Internet , Internet Use , Parenting , Prospective Studies
9.
Front Psychol ; 13: 856623, 2022.
Article in English | MEDLINE | ID: mdl-35496196

ABSTRACT

Learning grammar requires practice and practicing grammar can be boring. We examined whether an instructional game with intrinsically integrated game mechanics promotes this practice: compared to rote learning through a quiz. We did so "in the field." Tens of thousands children visited, in their leisure time, a public website with tens of attractive online games for children during a 6-week-long period. Of these children, 11,949 picked voluntarily our grammar training intervention. Thereafter, unbeknown to them, they were assigned either to the game or the quiz condition. By means of learning analytics, we examined variables related to participants' persistence and performance. The results showed large participant drop-out before completing the first level in both conditions (42.2%), confirming the boringness of the topic. More children completed at least one level in the game compared to the quiz (61.8 vs. 53.6%). However, more children completed the intervention (all six levels) with the quiz (6.0 vs. 4.3%). In the game, children answered fewer questions correctly (36.3 vs. 47.4) and made more errors compared to the quiz (16.1 vs. 13.1). These findings suggest that even if a game initially catches user attention, it may not hold it. Plus, even if it is a minimalistic game with intrinsic integration of learning and playing, it may be distractive. We conclude that persistence in practicing grammar may be driven by other means than by a game's shooting mechanics; for instance, by a desire to learn the topic and a feeling of achievement or by quizzing mechanics.

10.
Psychophysiology ; 59(10): e14075, 2022 10.
Article in English | MEDLINE | ID: mdl-35460523

ABSTRACT

Functional connectivity analysis is a common approach to the characterization of brain function. While studies of functional connectivity have predominantly focused on resting-state fMRI, naturalistic paradigms, such as movie watching, are increasingly being used. This ecologically valid, yet relatively unconstrained acquisition state has been shown to improve subject compliance and, potentially, enhance individual differences. However, unlike the reliability of resting-state functional connectivity, the reliability of functional connectivity during naturalistic viewing has not yet been fully established. The current study investigates the intra-session reliability of functional connectivity during naturalistic viewing sessions to extend its understanding. Using fMRI data of 24 subjects measured at rest as well as during six naturalistic viewing conditions, we quantified the split-half reliability of each condition, as well as cross-condition reliabilities. We find that intra-session reliability is relatively high for all conditions. While cross-condition reliabilities are higher for pairings of two naturalistic viewing conditions, split-half reliability is highest for the resting state. Potential sources of variability across the conditions, as well as the strengths and limitations of using intra-session reliability as a measure in naturalistic viewing, are discussed.


Subject(s)
Brain , Magnetic Resonance Imaging , Brain/diagnostic imaging , Brain Mapping , Humans , Individuality , Motion Pictures , Reproducibility of Results
11.
PeerJ ; 10: e13187, 2022.
Article in English | MEDLINE | ID: mdl-35411252

ABSTRACT

Humans can memorize and later recognize many objects and complex scenes. In this study, we prepared large photographs and presented participants with only partial views to test the fidelity of their memories. The unpresented parts of the photographs were used as a source of distractors with similar semantic and perceptual information. Additionally, we presented overlapping views to determine whether the second presentation provided a memory advantage for later recognition tests. Experiment 1 (N = 28) showed that while people were good at recognizing presented content and identifying new foils, they showed a remarkable level of uncertainty about foils selected from the unseen parts of presented photographs (false alarm, 59%). The recognition accuracy was higher for the parts that were shown twice, irrespective of whether the same identical photograph was viewed twice or whether two photographs with overlapping content were observed. In Experiment 2 (N = 28), the memorability of the large image was estimated by a pre-trained deep neural network. Neither the recognition accuracy for an image part nor the tendency for false alarms correlated with the memorability. Finally, in Experiment 3 (N = 21), we repeated the experiment while measuring eye movements. Fixations were biased toward the center of the original large photograph in the first presentation, and this bias was repeated during the second presentation in both identical and overlapping views. Altogether, our experiments show that people recognize parts of remembered photographs, but they find it difficult to reject foils from unseen parts, suggesting that their memory representation is not sufficiently detailed to rule them out as distractors.


Subject(s)
Memory , Recognition, Psychology , Humans , Mental Recall , Eye Movements , Semantics
12.
PeerJ ; 10: e13031, 2022.
Article in English | MEDLINE | ID: mdl-35261822

ABSTRACT

Although the Multiple Object Tracking (MOT) task is a widely used experimental method for studying divided attention, tracking objects in the real world usually looks different. For example, in the real world, objects are usually clearly distinguishable from each other and also possess different movement patterns. One such case is tracking groups of creatures, such as tracking fish in an aquarium. We used movies of fish in an aquarium and measured general tracking performance in this task (Experiment 1). In Experiment 2, we compared tracking accuracy within-subjects in fish tracking, tracking typical MOT stimuli, and in a third condition using standard MOT uniform objects which possessed movement patterns similar to the real fish. This third condition was added to further examine the impact of different motion characteristics on tracking performance. Results within a Bayesian framework showed that tracking real fish shares similarities with tracking simple objects in a typical laboratory MOT task. Furthermore, we observed a close relationship between performance in both laboratory MOT tasks (typical and fish-like) and real fish tracking, suggesting that the commonly used laboratory MOT task possesses a good level of ecological validity.


Subject(s)
Motion Perception , Rubella , Humans , Bayes Theorem , Attention , Research Design
13.
Front Psychol ; 12: 678380, 2021.
Article in English | MEDLINE | ID: mdl-34489794

ABSTRACT

Instructional quizzes are frequently used in educational games. When they present correct answers after learners have responded, these quizzes can be used on their own for teaching new factual and conceptual knowledge (no additional learning materials are needed). In games, these quizzes are often unrelated to gameplay: gameplay can be viewed as a reward for answering quiz questions. This has been criticized in game-based learning literature as a "chocolate-covered-broccoli" approach. However, is it really a bad approach? Theories offer conflicting predictions concerning the instructional efficiency of in-game quizzes relative to bare quizzes (i.e., not embedded in games) and empirical literature is lacking. Here, we present a within-subject design study (N = 69), in which 10-12-year-olds learn from both an in-game quiz and a bare quiz and undergo immediate and 2-3 weeks delayed post-test on the quiz questions. A modest difference in learning outcomes favoring the bare quiz was found in the immediate post-tests (d = 0.46), but not in the 2-3 weeks delayed post-tests (d = 0.09). Children enjoyed the game more than the bare quiz (d z = 0.65) and 59 preferred the game in the free-choice period. The findings suggest that both a bare quiz and a quiz within a game have their place at the table for useful educational interventions: the bare quiz should be preferred in schooling contexts; whereas, the game in leisure time situations as a voluntary activity. In the latter case, it should be considered how the game and the quiz are integrated.

14.
Article in English | MEDLINE | ID: mdl-34444307

ABSTRACT

The COVID-19 outbreak and related restrictions meant a higher incidence of screen-related risk behaviors in both children and adolescents. Our goal was to assess the perceived importance and extent of school-based preventions related to these risks during the long-term, nation-wide distant schooling period in the Czech Republic. The online survey was responded to by the school-based prevention specialists (N = 1698). For the analysis, within-subject analysis of variance (ANOVA) and binominal logistic regression were used. At-risk internet use and cyber-bullying were perceived as pressing, but other risks, for example, excessive internet use or the use of cyberpornography, received substantially less priority. The differences in all grades were significant and moderate to large (η2G between 0.156 and 0.288). The proportion of schools which conducted prevention interventions of screen-related risks was low (between 0.7% and 27.8%, depending on the grade and the type of the risk). The probability of delivering prevention intervention was in all grades significantly predicted by the presence of screen-related problems in pupils (OR 3.76-4.88) and the perceived importance of the screen-related risks (OR 1.55-1.97). The limited capacity of schools to deliver prevention interventions during distant schooling as well as the low awareness and impaired ability to recognize the importance of some screen-related risks should be addressed.


Subject(s)
COVID-19 , Adolescent , Child , Cross-Sectional Studies , Disease Outbreaks , Humans , Risk-Taking , SARS-CoV-2 , Schools , Surveys and Questionnaires
15.
Quant Imaging Med Surg ; 11(7): 3219-3233, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34249648

ABSTRACT

BACKGROUND: Invasive treatments for atrial fibrillation (AF) pose a risk of ischemic stroke due to periprocedural brain embolization, which may be manifest or silent. The primary aim of our study was to compare the rate of silent strokes after percutaneous catheter-based and thoracoscopic epicardial ablation for AF. The secondary aim was to evaluate the development of silent strokes over time. METHODS: We included 39 subjects (aged 64.1±8.9 years) treated for persistent symptomatic AF with thoracoscopic ablation and 30 subjects (aged 64.1±10.5 years) treated for paroxysmal or persistent symptomatic AF with catheter ablation. Subjects underwent brain MRI before and early after the ablation, moreover, the surgical group underwent late MRI 6 months after therapy. On early MRI, the presence of silent strokes and their number and size were evaluated. On late MRI, transformation of previously-detected acute ischemic lesions into chronic infarction or their reversibility were assessed. RESULTS: Initially, different chronic ischemic findings were found in 64% of patients from the surgical group and in 70% from catheter group. Early MRI results: acute ischemic lesions were detected in 2 (6.7%) subjects (overall 3 lesions sized <5 mm) in the catheter group and in 17 (43.6%) subjects in surgical group. Most subjects in the surgical group showed multiple lesions (88%); 195 lesions were detected, a median 6 (IQR 8) lesions per case. Eighty-two percent of lesions were <5 mm, 12% 5-10 mm, 5% 10-30 mm, and 2% were large territorial ischemia. Only 1 case was symptomatic, the rest were silent strokes. On late MRI, 53.5% of all acute lesions were reversible. Lesions <5 mm were reversible in 63.1% of cases, lesions 5-10 mm were reversible in 21.7% and all lesions larger than 10 mm persisted. In 29.4% of patients all acute ischemic lesions were fully reversible. CONCLUSIONS: Periprocedural silent strokes were significantly more common after thoracoscopic epicardial ablation compared to catheter ablation considering both the number of affected patients and number of lesions. The majority of acute ischemic brain lesions were small, up to 5 mm in diameter, roughly half of which were reversible. Reversibility of acute ischemic lesions decreased with size. However, in 29.4% of affected patients, all lesions were fully reversible.

16.
Vision Res ; 178: 48-59, 2021 01.
Article in English | MEDLINE | ID: mdl-33113436

ABSTRACT

People are remarkably good at remembering photographs. To further investigate the nature of the stored representations and the fidelity of human memories, it would be useful to evaluate the visual similarity of stimuli presented in experiments. Here, we explored the possible use of convolutional neural networks (CNN) as a measure of perceptual or representational similarity of visual scenes with respect to visual memory research. In Experiment 1, we presented participants with sets of nine images from the same scene category and tested whether they were able to detect the most distant scene in the image space defined by CNN. Experiment 2 was a visual variant of the Deese-Roediger-McDermott paradigm. We asked participants to remember a set of photographs from the same scene category. The photographs were preselected based on their distance to a particular visual prototype (defined as centroid of the image space). In the recognition test, we observed higher false alarm rates for scenes closer to this visual prototype. Our findings show that the similarity measured by CNN is reflected in human behavior: people can detect odd-one-out scenes or be lured to false alarms with similar stimuli. This method can be used for further studies regarding visual memory for complex scenes.


Subject(s)
Memory , Mental Recall , Humans , Neural Networks, Computer
17.
Quant Imaging Med Surg ; 10(10): 1908-1916, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33014724

ABSTRACT

BACKGROUND: The initial core infarct volume predicts treatment outcome in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). According to the literature, CT perfusion (CTP) is able to evaluate cerebral parenchymal viability and assess the initial core in AIS. We prospectively studied whether limited-coverage CTP with automated core calculation correlates with the final infarct volume on follow-up non-enhanced CT (NECT) in patients successfully treated by mechanical thrombectomy. METHODS: We enrolled 31 stroke patients (20 women aged 74.4±12.9 years and 11 men aged 66±15.4 years; median initial NIHSS score 15.5) with occlusion of the medial cerebral artery and/or the internal carotid artery that were treated by successful mechanical thrombectomy. CTP performed in a 38.6 mm slab at the level of basal ganglia was included in the CT stroke protocol, but was not used to determine indication for mechanical thrombectomy. The infarction core volume based on CTP was automatically calculated using dedicated software with a threshold defined as cerebral blood flow <30% of the value in the contralateral healthy hemisphere. The final infarction volume was measured on 24-hour follow-up NECT in the same slab with respect to CTP. Pearson and Spearman correlation coefficients and robust linear regression were used for comparison of both volumes, P values <0.05 were considered as statistically significant. RESULTS: The median time from stroke onset to CT was 77 minutes (range, 31-284 minutes), and the median time from CT to vessel recanalization was 95 minutes (range, 55-215 minutes). The mean CTP-calculated core infarct volume was 24.3±19.2 mL (median 19 mL, range 1-79 mL), while the mean final infarct volume was 21.5±39.5 mL (median 8 mL; range 0-210 mL). Only a weak relationship was found between the CTP-calculated core and final infarct volume [Pr(29) =0.32, P=0.078; rho =0.40, P=0.028]. Regression analysis showed CTP significantly overestimated lower volumes. CONCLUSIONS: In our prospective study, the infarction core calculated using limited-coverage CTP only weakly correlated with the final infarction volume measured on 24-hour follow-up NECT; moreover, CTP significantly overestimated lower volumes. Our results do not support the use of limited-coverage CTP for guiding treatment recommendations in patients with AIS.

18.
PLoS One ; 15(6): e0232570, 2020.
Article in English | MEDLINE | ID: mdl-32484832

ABSTRACT

In the last years, there has been a considerable increase of research into the neuroimaging correlates of inter-individual temperament and character variability-an endeavour for which the term 'personality neuroscience' was coined. Among other neuroimaging modalities and approaches, substantial work focuses on functional connectivity in resting state (rs-FC) functional magnetic resonance imaging data. In the current paper, we set out to independently query the questions asked in a highly cited study that reported a range of functional connectivity correlates of personality dimensions assessed by the widely used 'Big Five' Personality Inventory. Using a larger sample (84 subjects) and an equivalent data analysis pipeline, we obtained widely disagreeing results compared to the original study. Overall, the results were in line with the hypotheses of no relation between functional connectivity and personality, when more precise permutation-based multiple testing procedures were applied. The results demonstrate that as with other neuroimaging studies, great caution should be applied when interpreting the findings, among other reasons due to multiple testing problem involved at several levels in many neuroimaging studies. Of course, the current study results can not ultimately disprove the existence of some link between personality and brain's intrinsic functional architecture, but clearly shows that its form is very likely different and much more subtle and elusive than was previously reported.


Subject(s)
Brain/physiology , Personality/physiology , Adult , Brain/diagnostic imaging , Brain Mapping , Female , Humans , Magnetic Resonance Imaging , Male , Neural Pathways/diagnostic imaging , Neural Pathways/physiology , Personality Tests , Rest
19.
Percept Mot Skills ; 127(1): 75-97, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31547784

ABSTRACT

The present research was motivated by the routine digital media practice of producing page layouts as composite images that include several unrelated pictures. We investigated whether or how visually highlighting affective and positional components of pictures in a viewer's field of vision might influence viewer perception and evaluation of the composite image. We examined combinations of visual, spatial, and affective features of cues in composite images to learn whether they affected the viewer's attentional capture of other affective information in the composite image and viewer's affective evaluations. The manipulation check of the feature combinations (positive/negative affect, presence/absence of highlighted color, central/peripheral position) showed significant effects of these features and their interactions on viewers' eye movements. On the other hand, we observed only a small effect on viewers' affective evaluations. Our results suggested that media page layout designers might manipulate the viewer's attention by visual and positional adjustments of affective components in composite images. Future researchers might use this study's design to better understand the human perception of real media images.


Subject(s)
Affect/physiology , Attention/physiology , Cues , Eye Movements/physiology , Visual Perception/physiology , Adult , Arousal/physiology , Female , Humans , Learning/physiology , Male , Middle Aged , Photic Stimulation , Young Adult
20.
Front Psychol ; 10: 1224, 2019.
Article in English | MEDLINE | ID: mdl-31191412

ABSTRACT

Cognitive performance is dynamic and shaped by individual biological and environmental factors throughout life. In psychology, besides the effects of age, education, and other often studied factors, the complexity of the lived-in environment and urbanicity in that context are yet to be elucidated. In this observational cross-sectional study, we compare cognitive performance in standard neuropsychological tests in healthy older persons from three different types of settlements in the Czechia: the capital city of Prague, towns, and villages. The groups were equal in terms of the age-band (60-74 years), the distribution of gender, education, past and current leisure activities, and cognitive health status (MMSE score). The results showed that Prague citizens had consistently better performance in all verbal tests (for memory and verbal control, i.e., executive function) and attention than persons from other areas. The groups did not differ in timed visuo-graphomotor performance. The conclusion is that the complex environment of a city may promote, in the long-term, certain cognitive abilities, distinguishable even in a developed, culturally homogenous country. The implications are: (a) the description of samples used in normative studies should include information on the lived-in environment for the reference of researchers and clinicians; and (b) individual clinical assessment should reflect the role of the patient's environment where appropriate. The exact mechanisms and causes of the differences need further investigation.

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