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Purpose: To evaluate the feasibility of spatio-temporal encoding (SPEN) readout for pseudo-continuous ASL (pCASL) in brain, and its robustness to susceptibility artifacts as introduced by aneurysm clips. Methods: A 2D self-refocused T-2*-compensated hybrid SPEN scheme, with super-resolution reconstruction was implemented on a 1.5T Philips system. Q (=BWchirp*T-chirp) was varied and, the aneurysm clip-induced artifact was evaluated in phantom (label-images) as well as in vivo (perfusion-weighted signal (PWS)-maps and temporal SNR (tSNR)). In vivo results were compared to gradient-echo EPI (GE-EPI) and spin-echo EPI (SE-EPI). The dependence of tSNR on TR was evaluated separately for SPEN and SE-EPI. SPEN with Q similar to 75 encodes with the same off-resonance robustness as EPI. Results: The clip-induced artifact with SPEN decreased with increase in Q, and was smaller compared to SE-EPI and GE-EPI in vivo. tSNR decreased with Q and the tSNR of GE-EPI and SE-EPI corresponded to SPEN with a Q-value of approximately similar to 85 and similar to 108, respectively. In addition, SPEN perfusion images showed a higher tSNR (p < 0.05) for TR = 4000 ms compared to TR = 2100 ms, while SE-EPI did not. tSNR remained relatively stable when the time between SPEN-excitation and start of the next labeling-module was more than similar to 1000 ms. Conclusion: Feasibility of combining SPEN with pCASL imaging was demonstrated, enabling cerebral perfusion measurements with a higher robustness to field inhomogeneity (Q > 75) compared to SE-EPI and GE-EPI. However, the SPEN chirp-pulse saturates incoming blood, thereby reducing pCASL labeling efficiency of the next acquisition for short TRs. Future developments are needed to enable 3D scanning.

The present project investigates differences in recognition memory for lists of words that are either studied silently, read aloud, or signed in American Sign Language (ASL). The research question of interest is how producing a word by speech or through signing impacts a person's memory during study. Additionally, we investigated the role of language fluency in ASL by including participants who were currently enrolled in a first- or third-year ASL course.

This study investigated the relationship between ASL fingerspelling and letter representations

Mathematical learning constitutes a critical part of academic development for students across grades. It has been suggested that math ability is tightly associated with multiple general cognitive factors including language (Fuchs et al., 2005; 2010), working memory (Purpura & Ganley, 2014; Bull et al., 2008) and visual-spatial (Mix et al., 2016) capabilities. However, to what extent could these cognitive components impact different arithmetic operations? For instance, different arithmetic operations may rely on visual-spatial and verbal resources to varied degrees. Specifically, it has been proposed that additions and subtractions may engage visual-spatial processes while multiplications tend to rely on phonological components involved in rote memorization (Lee & Kang, 2002; Mathieu et al., 2018; Crollen et al., 2019; Li et al., 2018; Guez et al., 2022). Nevertheless, previous findings are far from consistent and causal relationships have been rarely established (e.g., Simmons et al., 2012; Cavdaroglu & Knops, 2016; Chen et al., 2022). One way to examine the causal impact of cognitive factors on arithmetic performance is through the use of dual-task paradigms. In the dual-task, math performance is measured while a secondary task is undertaken simultaneously (e.g., performing addition trials while generating random letter strings in between; Hubber et al., 2014; Imbo & Vandierendonck, 2007). In these paradigms, the degree to which math performance (the primary task) is interfered with by the secondary task is thought to indicate the degree to which cognitive components are shared between the two tasks. However, secondary task properties such as task requirements and stimulus parameters were not fully controlled in most previous studies. For instance, secondary task presentation (visual/auditory; McKenzie et al., 2003) or response modality (oral repetition/keypress; Imbo & Vandierendonck, 2007; Lee & Kang, 2002) were not held constant. Consequently, it is difficult to discern whether differences in the interference between the primary and secondary tasks arises from differences in the degree of cognitive overlap or from differences in experimental design parameters unrelated to core cognitive components (e.g., input/response modalities) across conditions. To overcome this limitation, we propose a dual-task paradigm in which bimodal bilinguals (i.e., children of deaf adults [CODAs] and sign language interpreters of varied proficiency) will be asked to perform mathematical computations while performing rhyme judgements in either verbal or sign language with pictorial stimuli. In this way, the secondary tasks can share same stimulus parameters, and impose the same task requirements, with linguistic modality being the only aspect that differs across tasks. The relationship between arithmetic performance and underlying cognitive factors can also be largely influenced by arithmetic strategies. Individuals may adopt various strategies to solve arithmetic problems, and thus engage different types of cognitive resources. For instance, mathematical fluent individuals tend to use the direct fact retrieval strategy when solving easy/highly familiar operations (e.g., 2 x 3, 4 + 5) and as a result, do not rely to a great extent on the visual-spatial sketchpad or phonological loop (Seitz & Schumann-Hengsteler, 2000; Imbo & Vandierendonck, 2007). Also, the postulated association between visual-spatial processes and additions/subtractions is most prominent for children in lower grades, when they are still trying to establish the mapping between magnitude manipulations and arithmetic operations (van der Ven et al., 2013). In contrast, as students enter higher grades, they appear to increasingly rely on phonological and visual-spatial resources to solve addition problems (McKenzie et al., 2003). Moreover, estimation and exact calculation of additions/subtractions may be associated with spatial representations to differential degrees. For example, the canonical operation-momentum effect describes the spatial-induced behavioral bias to overestimate addition answers and underestimate subtraction answers (McCrink et al., 2007; Knops et al., 2009). Conversely, the operation-momentum effect has not been found for exact symbolic calculations in any operation type (e.g., Katz & Knops, 2014). Given all the discussions above, the present study attempts to rule out the confound introduced by arithmetic strategies. Firstly, instead of exact calculation of additions/subtractions, we use an approximate numerical distance comparisons (e.g., estimating and comparing distance of 2335 with 3559) to facilitate spatial strategies. Secondly, only more difficult multiplication problems (e.g., 6 x 17) will be presented to avoid use of the direct fact retrieval strategy. The first goal of the present study is to examine how phonological and visual-spatial processes involved in verbal and sign language respectively may differentially impact arithmetic operations. Sign language, by nature, involves visual-spatial components including hand shape, location, orientation and movement (Brentari 2011). Accordingly, sign language processing activates brain regions such as the superior and inferior parietal lobe, which are commonly recruited by visual-spatial tasks more generally (Buchsbaum et al., 2005; MacSweeney et al., 2008). Thus, sign language processing would be expected to interfere to a greater extent with approximate numerical distance comparisons than with multiplications, which place fewer demands on visual processing. The second goal of the present study is to explore the influence of sign language proficiency on different types of arithmetic performance. Studying native hearing signers has the potential to inform future studies into math learning in deaf signers. Indeed, children with profound deafness have been consistently found to lag behind their hearing peers in overall math performance (Bull et al., 2005; Kritzer, 2009), and this trend persists into adulthood (Kelly et al., 2003). Researchers have attributed these math learning difficulties to the fact that a large proportion of the deaf population contends with varying degrees of language deprivation, especially in their early life (Santos & Cordes, 2021). Ninety percent of deaf children are born into hearing families, who often are not given the resources and tools to appropriately support the timely acquisition of language. However, deaf children who learn a signed language from birth demonstrate both higher sign language proficiency and greater math achievements compared with those with poorer sign language proficiency (Hrastinski & Wilbur, 2016). This suggests that it is the quality of language exposure and proficiency that contributes to academic achievement. Thus, our hypothesis is that greater proficiency in sign language leaves more visual-spatial resources available for other tasks that draw on this same pool of cognitive resources. We would thus predict that individuals with high sign language proficiency would also show better performance in approximate numerical distance comparisons than those with poorer proficiency. Specifically, we expect less pronounced interference from the secondary sign language task for CODAs than interpreters, who typically acquire sign language later in life. The inclusion of CODAs in addition to non-native interpreters may provide stronger inferences for deaf signers who also tend to learn signing early in life.

This portfolio is a collection of essays tying together perspectives and major themes in second language teaching of importance to the writer. It begins with an introduction piece, followed by a description of professional environment and a teaching philosophy statement focused on teacher-student relationships, varied assessments, and culture-focused teaching. This section is followed by a classroom observation. The main section of the portfolio is a reflection paper presenting perspectives on the importance of providing interaction opportunities in asynchronous online language learning classrooms. The portfolio concludes with a statement of future goals.

Concussion is associated with acute disturbances in brain function and behavior, with potential long‐term effects on brain health. However, it is presently unclear whether there are sex differences in acute and long‐term brain recovery. In this study, magnetic resonance imaging (MRI) was used to scan 61 participants with sport‐related concussion (30 male, 31 female) longitudinally at acute injury, medical clearance to return to play (RTP), and 1‐year post‐RTP. A large cohort of 167 controls (80 male, 87 female) was also imaged. Each MRI session assessed cerebral blood flow (CBF), along with white matter fractional anisotropy (FA) and mean diffusivity (MD). For concussed athletes, the parameters were converted to difference scores relative to matched control subgroups, and partial least squares modeled the main and sex‐specific effects of concussion. Although male and female athletes did not differ in acute symptoms or time to RTP , all MRI measures showed significant sex differences during recovery. Males had greater reductions in occipital‐parietal CBF (mean difference and 95%CI: 9.97 ml/100 g/min, [4.84, 15.12] ml/100 g/min, z = 3.73) and increases in callosal MD (9.07 × 10−5, [−14.14, −3.60] × 10−5, z = −3.46), with greatest effects at 1‐year post‐RTP. In contrast, females had greater reductions in FA of the corona radiata (16.50 × 10−3, [−22.38, −11.08] × 10−3, z = −5.60), with greatest effects at RTP. These findings provide new insights into how the brain recovers after a concussion, showing sex differences in both the acute and chronic phases of injury., This study examined whether there are sex differences in acute and long‐term brain changes after concussion. Male athletes showed greater declines in cerebral blood flow, whereas both sexes showed unique alterations in white matter microstructure. These sex differences were present at acute injury and remained up to 1 year after medical clearance.

Mild traumatic brain injury (mTBI), frequently referred to as concussion, is one of the most common neurological disorders. The underlying neural mechanisms of functional disturbances in the brains of concussed individuals remain elusive. Novel forms of brain imaging have been developed to assess patients postconcussion, including functional magnetic resonance imaging (fMRI), susceptibility‐weighted imaging (SWI), diffusion MRI (dMRI), and perfusion MRI [arterial spin labeling (ASL)], but results have been mixed with a more common utilization in the research environment and a slower integration into the clinical setting. In this review, the benefits and drawbacks of the methods are described: fMRI is an effective method in the diagnosis of concussion but it is expensive and time‐consuming making it difficult for regular use in everyday practice; SWI allows detection of microhemorrhages in acute and chronic phases of concussion; dMRI is primarily used for the detection of white matter abnormalities, especially axonal injury, specific for mTBI; and ASL is an alternative to the BOLD method with its ability to track cerebral blood flow alterations. Thus, the absence of a universal diagnostic neuroimaging method suggests a need for the adoption of a multimodal approach to the neuroimaging of mTBI. Taken together, these methods, with their underlying functional and structural features, can contribute from different angles to a deeper understanding of mTBI mechanisms such that a comprehensive diagnosis of mTBI becomes feasible for the clinician., Mild traumatic brain injury (mTBI), frequently referred to as concussion, is one of the most common neurological disorders. The underlying neural mechanisms of functional disturbances in the brains of concussed individuals remain elusive. Novel forms of brain imaging have been developed to assess patients postconcussion, including fMRI, SWI, diffusion MRI (dMRI), and perfusion MRI [arterial spin labeling (ASL)], but results have been mixed with a more common utilization in the research environment and a slower integration into the clinical setting. In this review, the benefits and drawbacks of the methods are described.

Poster presentation for HDLS14 with poster PDF, videorecorded presentation, subtitles and image descriptions

The present experiment builds on a design from Chan and Kelly (2021) (https://osf.io/8bd3n/). Quoting from their description: “Previous studies on cross-linguistic differences of agency perception have noted that various languages have different ways of marking between accidental and intentional events. Agentive languages like English prefer to describe both types of events in an active voice and non-agentive languages like Japanese distinguish between the two types of events with the use of distinct verb forms. These linguistic differences in speech have been shown to affect how speakers perceive and remember agency, though whether similar effects can be seen when agency is depicted in other modalities have yet to be explored. In our project, we will present visual portrayals of agency through two types of co-speech gestures - character-viewpoint gestures that mimic an agent performing an action and object-viewpoint gestures that represent the motion trajectory of an object without any reference to an agent. We will pair active and passive sentences with character-viewpoint and object-viewpoint gestures to determine if gestures interact with speech to disrupt the way listeners assign responsibility to the speaker and remember events during a surprise memory task.” (Kelly & Chan, 2021) End Quote Building off of this previous work, the present study explores this phenomenon from the lens of American Sign Language. We broadly ask the question: “Does knowledge of sign language have an effect on the way people interpret agency through speech and co-speech gesture?”

Poster presentation for HDLS14 with poster PDF, videorecorded presentation, subtitles and image descriptions

Background: Major depressive disorder (MDD) is a serious health problem, affecting over 300 million people worldwide. MDD is the leading cause of disability, measured in Years Lived with Disability, and it globally leads to suicide of 800k people each year (World Health Organization, 2020). Numerous treatments, including antidepressant (AD) drug treatment, are available. The selection of AD treatment in a given patient presently approximates ‘a trial-and-error approach’. Only one third of the patients show significant symptom relief in response to the initial treatment (Rush et al., 2009) and 50% have not found an efficacious antidepressant (AD) after 1 year (Keitner et al., 1992; Rush, 2007). Concurrently, patients are exposed to possible side effects of AD drugs, including dry mouth, weight gain, sexual adverse effects and/or insomnia. These side effects occur shortly after treatment has started, while the effect of treatment can currently only be assessed after 6 weeks. Patients are thus exposed to a longer period of exposure to possible side effects, with a potentially insufficient effect of treatment. Clearly, this raises a need for faster assessment of the effect of treatment. In order to advance fast and successful treatment of patients with MDD, we aim to develop a model for prediction of AD treatment response using baseline and first week follow-up data. MDD treatment response has been associated with several grey matter, white matter, and functional (blood flow and resting state functional) biomarkers in several regions of interests (ROIs) as prior neuroimaging research has already pointed out (Schrantee, Ruhe and Reneman, 2020). Whereas previous research typically studied biomarkers in a single Magnetic Resonance Imaging (MRI) modality (e.g., structural MRI), this work has a multimodal approach, combining structural MRI (sMRI), diffusion tensor (DTI), resting state functional MRI (rs-fMRI), and arterial spin labeling (ASL). Despite promising results shown in task-based fMRI, this modality was excluded from this work due concerns about reproducibility and complexity of a potential clinical application (Klomp et al., 2013). Additionally, we will add relevant demographic data specified and motivated later on in this document. The Hamilton Rating Scale for Depression (HRSD, also known as HRSD and HAM-D) at week eight is the primary end point in our model. This algorithm will be developed using the EMBARC dataset (Trivedi, McGrath, et al., 2016), part of the publicly available National Data Archive (NDA) of the National Institute of Mental Health (NIMH). This study was explicitly designed allow discovery of multimodal neuroimaging biomarkers and overcomes previous sample sizes limitations. A complete overview of the study design and data collected can be found at the NDA website (Trivedi, Weissman, et al., 2016). Treatment in EMBARC consists of two phases: in phase I patients were randomly allocated to 8 weeks of sertraline or placebo. In Phase II the placebo non-responders were treated with sertraline in second instance and sertraline non-responders with bupropion for 8 weeks. The EMBARC dataset consists of MRI neuroimaging in Phase I (before and after 1 week (early) treatment) and clinical and demographic characteristics. Patients were scanned before (baseline), and after the first week of treatment (early-treatment). Research Questions (RQ): 1. Are we able to predict AD response (≥50% decrease in HRSD) and remission (HRSD≤7) based on baseline and/or early-treatment MR imaging modalities and patient information? 2. If successful, does this algorithm show specificity for sertraline treatment response when its performance is compared to performance in placebo treated subjects to predict response? 3. Can we replicate the predictive accuracy for response and remission in the (selected) placebo non-responders who have been treated with sertraline in 2nd instance thereafter? 4. If successful, how much does each MRI modality contribute to the prediction made?

Background Arterial spin labeling (ASL) is a noninvasive brain perfusion magnetic resonance imaging (MRI) technique that has not been assessed in clinical veterinary medicine. Hypothesis/Objectives To test the feasibility of ASL using a 1.5 Tesla scanner and provide recommendations for optimal quantification of cerebral blood flow (CBF) in dogs and cats. Animals Three hundred fourteen prospectively selected client‐owned dogs and cats. Methods Each animal underwent brain MRI including morphological sequences and ≥1 ASL sequences using different sites of blood labeling and postlabeling delays (PLD). Calculated ASL success rates were compared. The CBF was quantified in animals that had morphologically normal brain MRI results and parameters of ASL optimization were investigated. Results Arterial spin labeling was easily implemented with an overall success rate of 95% in animals with normal brain MRI. Technical recommendations included (a) positioning of the imaging slab at the foramen magnum and (b) selected PLD of 1025 ms in cats and dogs 38 kg. In 37 dogs, median optimal CBF in the cortex and thalamic nuclei were 114 and 95 mL/100 g/min, respectively. In 28 cats, median CBF in the cortex and thalamic nuclei were 113 and 114 mL/100 g/min, respectively. Conclusions and Clinical Importance Our survey of brain perfusion ASL‐MRI demonstrated the feasibility of ASL at 1.5 Tesla, suggested technical recommendations and provided CBF values that should be helpful in the characterization of various brain diseases in dogs and cats.

Background Dynamic contrast-enhanced (DCE) MRI is the most sensitive method for detection of breast cancer. However, due to high costs and retention of intravenously injected gadolinium-based contrast agent, screening with DCE-MRI is only recommended for patients who are at high risk for developing breast cancer. Thus, a noncontrast-enhanced alternative to DCE is desirable. Purpose To investigate whether velocity selective arterial spin labeling (VS-ASL) can be used to identify increased perfusion and vascularity within breast lesions compared to surrounding tissue. Study type Prospective. Population Eight breast cancer patients. Field strength/sequence A 3 T; VS-ASL with multislice single-shot gradient-echo echo-planar-imaging readout. Assessment VS-ASL scans were independently assessed by three radiologists, with 3-25 years of experience in breast radiology. Scans were scored on lesion visibility and artifacts, based on a 3-point Likert scale. A score of 1 corresponded to "lesions being distinguishable from background" (lesion visibility), and "no or few artifacts visible, artifacts can be distinguished from blood signal" (artifact score). A distinction was made between mass and nonmass lesions (based on BI-RADS lexicon), as assessed in the standard clinical exam. Statistical tests Intra-class correlation coefficient (ICC) for interobserver agreement. Results The ICC was 0.77 for lesion visibility and 0.84 for the artifact score. Overall, mass lesions had a mean score of 1.27 on lesion visibility and 1.53 on the artifact score. Nonmass lesions had a mean score of 2.11 on lesion visibility and 2.11 on the artifact score. Data conclusion We have demonstrated the technical feasibility of bilateral whole-breast perfusion imaging using VS-ASL in breast cancer patients. Evidence level 1 TECHNICAL EFFICACY: Stage 1.

Yuki Motomura,1– 3 Shingo Kitamura,1 Kyoko Nakazaki,1 Kentaro Oba,1,4 Ruri Katsunuma,1,3 Yuri Terasawa,1,5 Akiko Hida,1 Yoshiya Moriguchi,1,3 Kazuo Mishima1,6,7 1Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8553, Japan; 2Faculty of Design, Kyushu University, Fukuoka, 815-8540, Japan; 3Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, 187-8553, Japan; 4Department of Human Brain Science, Institute of Development, Aging and Cancer, Tohoku University, Sendai, 980-8575, Japan; 5Department of Psychology, Keio University, Kanagawa, 223-8521, Japan; 6Department of Neuropsychiatry, Akita University Graduate School of Medicine, Akita, 010-8543, Japan; 7International Institute for Integrative Sleep Medicine, University of Tsukuba, Ibaraki, JapanCorrespondence: Kazuo MishimaDepartment of Neuropsychiatry, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita, 010-8543, JapanTel +81 18 884 6122Fax +81 18 884 6445Email mishima@med.akita-u.ac.jpYuki MotomuraFaculty of Design, Kyushu University, 4-9-1 Shiobaru, Minami-ku, Fukuoka, 815-8540, JapanTel +81 92 533 9493Email motomura@design.kyushu-u.ac.jpPurpose: The thalamus, the region that forms the attentional network and transmits external sensory signals to the entire brain, is important for sleepiness. Herein, we examined the relationship between activity in the thalamus-seed brain network and subjective sleepiness.Materials and Methods: Fifteen healthy male participants underwent an experiment comprising a baseline evaluation and two successive interventions, a 9-day sleep extension followed by 1-night total sleep deprivation. Pre- and post-intervention tests included the Karolinska sleepiness scale and neuroimaging for arterial spin labeling and functional connectivity. We examined the association between subjective sleepiness and the functional magnetic resonance imaging indices.Results: The functional connectivity between the left or right thalamus and various brain regions displayed a significant negative association with subjective sleepiness, and the functional connectivity between the left and right thalamus displayed a significant positive association with subjective sleepiness. The graph theory analysis indicated that the number of positive functional connectivity related to the thalamus showed a strong negative association with subjective sleepiness, and conversely, the number of negative functional connectivity showed a positive association with subjective sleepiness. Arterial spin labeling analysis indicated that the blood flow in both the left and right thalami was significantly negatively associated with subjective sleepiness. Functional connectivity between the anterior cingulate cortex and salience network areas of the left insular cortex, and that between the anterior and posterior cingulate cortices showed a strong positive and negative association with subjective sleepiness, respectively.Conclusion: Subjective sleepiness and the thalamic-cortical network dynamics are strongly related, indicating the application of graph theory to study sleepiness and consciousness. These results also demonstrate that resting functional connectivity largely reflects the “state” of the subject, suggesting that the control of sleep and conscious states is essential when using functional magnetic resonance imaging indices as biomarkers.Keywords: sleep, subjective sleepiness, consciousness, functional connectivity, graph theory, rCBF, ASL

Self-directed learning views learning as an individual, powerful tool to learn at one’s own pace and on one’s own time. Adult self-learning aims at conjugating adult learning and self-directed learning. Hence, Chapter 1, Adult Self-Learning Methods and Techniques In Simulated Environments focuses on the most popular adult learning theories and methods, which include andragogy, transformative learning, experiential learning, self-directed learning, project-based learning, and action learning. The chapter presents the main assumptions of these theories, how they view adult learners, and what the ways of how to enhance adult learning through these methods, The European Commission support for the production of this publication does not constitute endorsement of the contents which reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein

Despite the fact that Talmy proposed a classification of languages according to their lexicalization patterns and the fact that a considerable amount of time has passed, there are still no didactic tools that facilitate the language students' acquisition of necessary mechanisms for descriptions of movements in second languages. Starting from previous researches of diverse authors where the difficulty and the absence of knowledge on the part of the student at the time of codifying the movement is verified, this work highlights the activities that use pedagogical translation as a facilitating vehicle for the learning of movement of English-speaking students of Spanish, with the purpose of avoiding the repetition of errors and being applicable to any language. Desde que Talmy propusiese por primera vez una clasificación de las lenguas en función de sus patrones de lexicalización hasta nuestros días, la descripción del movimiento sigue sin contar con herramientas didácticas que faciliten al estudiante de lenguas extranjeras la adquisición de los mecanismos necesarios para poder describir movimientos en la L2. Partiendo de investigaciones previas de diversos autores donde se comprueba la dificultad y la ausencia de conocimiento por parte del estudiante a la hora de codificar el movimiento, este trabajo expondrá actividades que hacen uso de la traducción pedagógica como vehículo facilitador para el aprendizaje del movimiento de estudiantes anglófonos de español con el fin de evitar la fosilización de errores y siendo estas aplicables a cualquier lengua.

Background:Cannabidiol (CBD) is being investigated as a potential treatment for several medical indications, many of which are characterised by altered memory processing. However, the mechanisms underlying these effects are unclear.Aims:Our primary aim was to investigate how CBD influences cerebral blood flow (CBF) in regions involved in memory processing. Our secondary aim was to determine if the effects of CBD on CBF were associated with differences in working and episodic memory task performance.Methods:We used a randomised, crossover, double-blind design in which 15 healthy participants were administered 600 mg oral CBD or placebo on separate days. We measured regional CBF at rest using arterial spin labelling 3 h after drug ingestion. We assessed working memory with the digit span (forward, backward) and n-back (0-back, 1-back, 2-back) tasks, and we used a prose recall task (immediate and delayed) to assess episodic memory.Results:CBD increased CBF in the hippocampus (mean (95% confidence intervals) = 15.00 (5.78–24.21) mL/100 g/min, t14= 3.489, Cohen’s d = 0.75, p = 0.004). There were no differences in memory task performance, but there was a significant correlation whereby greater CBD-induced increases in orbitofrontal CBF were associated with reduced reaction time on the 2-back working memory task ( r= −0.73, p = 0.005).Conclusions:These findings suggest that CBD increases CBF to key regions involved in memory processing, particularly the hippocampus. These results identify potential mechanisms of CBD for a range of conditions associated with altered memory processing, including Alzheimer’s disease, schizophrenia, post-traumatic stress disorder and cannabis-use disorders.

"Motivated Look at Indicating Verbs in ASL" (MoLo) is a corpus-based project at Gallaudet University, PIs - Julie A. Hochgesang, Paul Dudis, Ryan Lepic, Emily Shaw, and Miako Villanueva.

Attitudes to sign languages, or language policies, are often not overtly discussed or recorded but they influence deaf young people’s educational opportunities and outcomes. Two qualitative studies from Scotland investigate the provision of British Sign Language (BSL) as an accommodation in public examinations. The first explores the views of deaf pupils and staff about the official system for face-to-face interpretation of exam papers. The second investigates a centrally translated digital paper with embedded video questions. Discussion focuses on contrasts between the USA and UK approaches to accommodations, raising issues of standardised technical terms in signed languages, the right to respond in sign, and candidate choice.

The Deaf community’s relationship with language provides a new angle from which to study the role of phonemic elements in the interaction between lexemes and memory. Departing from a hearing canon and exploring a broader spectrum of language perception and production, we are able to revise questions on and develop insight into cognitive processes that influence memory. This paper will not attempt to ascertain whether the Deaf or the hearing have better memories; neurocognitive discrepancies between the groups prevent certain abilities from being compared under the same criteria. But there is no comprehensive “better,” only the space afforded by these discrepancies that allows for deeper understanding of neurolinguistic processes in conjunction with memory. To investigate the processes that influence Deaf memory, I compare studies on American Sign Language (ASL) and Japanese Sign Language (JSL). This comparison finds that when research on memory in the Deaf compared to the hearing is limited to English, the Deaf’s supposed deficit is the fault of the English language rather than a lack of phonological information. Linguistic models allow for a detailed understanding of information retrieval and the role of memory within language production. They also can narrow down variables of language-specific stimulus and when and where in cognition they come into play. The current standardized models of language production do not account for an inability to perceive audition. Thus, this paper will conclude by proposing a new Deaf language production model.

Peer reviewed: True, We sought to systematically review and meta-analy the role of cerebral blood flow (CBF) in the medial temporal lobe (MTL) using arterial spin labeling magnetic resonance imaging (ASL-MRI) and compare this in patients with Alzheimer's disease (AD), individuals with mild cognitive impairment (MCI), and cognitively normal adults (CN). The prevalence of AD is increasing and leading to high healthcare costs. A potential biomarker that can identify people at risk of developing AD, whilst cognition is normal or only mildly affected, will enable risk-stratification and potential therapeutic interventions in the future. All studies investigated the role of CBF in the MTL and compared this among AD, MCI, and CN participants. A total of 26 studies were included in the systematic review and 11 in the meta-analysis. Three separate meta-analyses were conducted. Four studies compared CBF in the hippocampus of AD compared with the CN group and showed that AD participants had 2.8 mL/min/100 g lower perfusion compared with the CN group. Eight studies compared perfusion in the hippocampus of MCI vs. CN group, which showed no difference. Three studies compared perfusion in the MTL of MCI vs. CN participants and showed no statistically significant differences. CBF measured via ASL-MRI showed impairment in AD compared with the CN group in subregions of the MTL. CBF difference was significant in hippocampus between the AD and CN groups. However, MCI and CN group showed no significant difference in subregions of MTL.

More than four million people worldwide suffer from hearing loss. Recently, new CNNs and deep ensemble-learning technologies have brought promising opportunities to the image-recognition field, so many studies aiming to recognize American Sign Language (ASL) have been conducted to help these people express their thoughts. This paper proposes an ASL Recognition System using Multiple deep CNNs and accuracy-based weighted voting (ARS-MA) composed of three parts: data preprocessing, feature extraction, and classification. Ensemble learning using multiple deep CNNs based on LeNet, AlexNet, VGGNet, GoogleNet, and ResNet were set up for the feature extraction and their results were used to create three new datasets for classification. The proposed accuracy-based weighted voting (AWV) algorithm and four existing machine algorithms were compared for the classification. Two parameters, α and λ, are introduced to increase the accuracy and reduce the testing time in AWV. The experimental results show that the proposed ARS-MA achieved 98.83% and 98.79% accuracy on the ASL Alphabet and ASLA datasets, respectively.

Optimal criteria for diagnosing and monitoring response to treatment for infectious and inflammatory medium–large vessel intracranial vasculitis presenting with stroke are lacking. We integrated intracranial vessel wall MRI with arterial spin labelling into our routine clinical stroke pathway to detect presumed inflammatory intracranial arterial vasculopathy, and monitor disease activity, in patients with clinical stroke syndromes. We used predefined standardized radiological criteria to define vessel wall enhancement, and all imaging findings were rated blinded to clinical details. Between 2017 and 2018, stroke or transient ischaemic attack patients were first screened in our vascular radiology meeting and followed up in a dedicated specialist stroke clinic if a diagnosis of medium–large inflammatory intracranial arterial vasculopathy was radiologically confirmed. Treatment was determined and monitored by a multi-disciplinary team. In this case series, 11 patients were managed in this period from the cohort of young stroke presenters (4 weeks compared with those not receiving therapy [6 (100%) versus 2 (40%) P = 0.026]. Our findings demonstrate the potential utility of vessel wall magnetic resonance with arterial spin labelling imaging in detecting and monitoring medium–large inflammatory intracranial arterial vasculopathy activity for patients presenting with stroke symptoms, limiting the need to progress to brain biopsy. Further systematic studies in unselected populations of stroke patients are needed to confirm our findings and establish the prevalence of medium–large artery wall inflammation.

Better understanding of cerebral blood flow (CBF) perfusion in stroke recovery can help inform decisions about optimal timing and targets of restorative treatments. In this study, we examined the relationship between cerebral perfusion and recovery from stroke‐induced reading deficits. Left stroke patients were tested with a noninvasive CBF measure (arterial spin labeling) 3 months post‐stroke. We measured blood flow perfusion within the left and right sides of the brain, in areas surrounding the lesion, and areas belonging to the reading network. Two hypotheses were tested. The first was that recovery of reading function depends on increased perfusion around the stroke lesion. This hypothesis was not supported by our findings. The second hypothesis was that increased perfusion of intact areas within the reading circuit is tightly coupled with recovery. Our findings are consistent with this hypothesis. Specifically, higher perfusion in the left reading network measured during the subacute stroke period predicted better reading ability and phonology competence in the chronic period. In contrast, higher perfusion of the right homologous regions was associated with decreased reading accuracy and phonology competence in the subacute and chronic periods. These findings suggest that recovery of reading and language competence may rely on improved blood flow in the reading network of the language‐dominant hemisphere.

BACKGROUND: Infiltrative gliomas show cerebral edema and tumor infiltration as areas of hyperintensity in FLAIR image. Amide proton transfer (APT) and cerebral blood flow (CBF) are useful for evaluating the tumor invasion. In this study, arterial spin-labeling (ASL)-CBF and APT were compared to determine which method was superior for predicting tumor infiltration in gliomas, pathologically. METHODS: Fifteen specimens from 5 glioma patients with confirmed selective sampling were obtained. Based on APT signal intensity (SI), regions of interests (ROIs) were selected for biopsy. Same regions of these ROIs were marked on the same slice of ASL imaging. Samples were pathologically assessed for cell density and vessel density. APT SI and ASL-CBF were analyzed for each specimen. RESULTS: APT signal intensity (SI) showed a strong correlation with cell density (R = 0.887, P < 0.0001). ASL-CBF showed no correlation with cell density (R = 0.240; P = 0.3836) but a correlation with vessel density (R = 0.697; P = 0.0038). In linear regression analysis, APT SI showed a positive relationship with cell density (R2 = 0.787, P < 0.0001, linear regression; y = 30.70 + 6.24E-3*x). CONCLUSIONS: APT imaging was superior in predicting cellular proliferation than ASL-CBF and a powerful predictor of cell density. APT imaging allowed revelation of novel clues reflecting tumor proliferation in brain tumor; to date, this is the first known report to assess cell density among various brain tumors and conditions after treatment.

Cerebral blood flow (CBF) measurements are of high clinical value and can be acquired non-invasively with no radiation exposure using pseudo-continuous arterial spin labeling (ASL). The aim of this study was to evaluate accordance in resting state CBF between ASL (CBFASL) and 15O-water positron emission tomography (PET) (CBFPET) acquired simultaneously on an integrated 3T PET/MR system. The data comprised ASL and dynamic 15O-water PET data with arterial blood sampling of eighteen subjects (eight patients with focal epilepsy and ten healthy controls, age 21 to 61 years). 15O-water PET parametric CBF images were generated using a basis function implementation of the single tissue compartment model. Cortical and subcortical regions were automatically segmented using Freesurfer. Average CBFASL and CBFPET in grey matter were 60 ± 20 and 75 ± 22 mL/100 g/min respectively, with a relatively high correlation (r = 0.78, p < 0.001). Bland-Altman analysis revealed poor agreement (bias = −15 mL/100 g/min, lower and upper limits of agreements = −16 and 45 mL/100 g/min, respectively) with a negative relationship. Accounting for the negative relationship, the width of the limits of agreement could be narrowed from 61 mL/100 g/min to 35 mL/100 g/min using regression-based limits of agreements. Although a high correlation between CBFASL and CBFPET was found, the agreement in absolute CBF values was not sufficient for ASL to be used interchangeably with 15O-water PET.

Arterial spin-labeled magnetic resonance imaging can provide quantitative perfusion measurements in the brain and can be potentially used to evaluate therapy response assessment in glioblastoma (GBM). The reliability and reproducibility of this method to measure noncontrast perfusion in GBM, however, are lacking. We evaluated the intrasession reliability of brain and tumor perfusion in both healthy volunteers and patients with GBM at 3 T using pseudocontinuous labeling (pCASL) and 3D turbo spin echo (TSE) using Cartesian acquisition with spiral profile reordering (CASPR). Two healthy volunteers at a single time point and 6 newly diagnosed patients with GBM at multiple time points (before, during, and after chemoradiation) underwent scanning (total, 14 sessions). Compared with 3D GraSE, 3D TSE-CASPR generated cerebral blood flow maps with better tumor-to-normal background tissue contrast and reduced image distortions. The intraclass correlation coefficient between the 2 runs of 3D pCASL with TSE-CASPR was consistently high (≥0.90) across all normal-appearing gray matter (NAGM) regions of interest (ROIs), and was particularly high in tumors (0.98 with 95% confidence interval [CI]: 0.97–0.99). The within-subject coefficients of variation were relatively low in all normal-appearing gray matter regions of interest (3.40%–7.12%), and in tumors (4.91%). Noncontrast perfusion measured using 3D pCASL with TSE-CASPR provided robust cerebral blood flow maps in both healthy volunteers and patients with GBM with high intrasession repeatability at 3 T. This approach can be an appropriate noncontrast and noninvasive quantitative perfusion imaging method for longitudinal assessment of therapy response and management of patients with GBM.

Work in literacy education over the past two decades has radically shifted the notion of literacy, broadening it to include the ability to engage with compositions in various media (e.g., not only traditional texts like books and articles but also vlogs, blogs, graphic novels etc.). The notion that literacy can apply to non-written compositions has led some to wonder about the development of “reading comprehension” of texts in languages like American Sign Language (ASL) that do not have a written form. However, there are no existing assessments of ASL text comprehension. In this paper, we introduce the ASL-CMP, a new assessment tool to measure American Sign Language (ASL) text comprehension ability in deaf children. We first administered the task to a group of deaf children with deaf parents (n = 105, ages 8-18 years) in order to evaluate the reliability and validity of the task, and to develop norms. We found that the ASL-CMP has acceptable levels of internal consistency, difficulty, and discriminability. Next, we administered the task to an additional group of deaf children with hearing parents (n = 198, ages 8-18 years), and found that the ASL-CMP is sensitive to expected patterns: older children have better ASL text comprehension skills, literal questions are generally easier to answer than inferential questions, and children with early exposure to ASL generally outperform those with delayed exposure. We conclude that the ASL-text comprehension task is reliable and valid and can be used to characterize comprehension skills in ASL in deaf children ages 8-12.

We propose a novel brain imaging method for objectively quantifying disease severity in Parkinson disease (PD). Levodopa pharmacological fMRI (phMRI) hysteresis mapping is based on the clinical observation that the benefit from a dose of levodopa wears off more quickly as PD progresses. Biologically this has been thought to represent decreased buffering capacity for dopamine as nigrostriatal cells die. Buffering capacity has been modeled previously based on clinical effects, but clinical measurements are influenced by confounding factors such as patient fatigue. The new method proposes to measure the effect directly and objectively based on the timing of the known metabolic and blood flow response of several brain regions to exogenous levodopa. Such responses are robust and can be quantified without ionizing radiation using perfusion MRI.Here we present simulation studies based on published clinical dose-response data and an intravenous levodopa infusion. Standard pharmacokinetic-pharmacodynamic methods were used to model the response. Then the effect site rate constant ke was estimated from simulated response data plus Gaussian noise.Predicted time:effect curves sampled at times consistent with phMRI differ substantially based on clinical severity. Estimated ke from noisy input data was recovered with good accuracy.These simulation results support the feasibility of levodopa phMRI hysteresis mapping to measure the severity of dopamine denervation objectively and simultaneously in several brain regions.

Hand gesture recognition is one of the most effective modes of interaction between humans and computers due to being highly flexible and user-friendly. A real-time hand gesture recognition system should aim to develop a user-independent interface with high recognition performance. Nowadays, convolutional neural networks (CNNs) show high recognition rates in image classification problems. Due to the unavailability of large labeled image samples in static hand gesture images, it is a challenging task to train deep CNN networks such as AlexNet, VGG-16 and ResNet from scratch. Therefore, inspired by CNN performance, an end-to-end fine-tuning method of a pre-trained CNN model with score-level fusion technique is proposed here to recognize hand gestures in a dataset with a low number of gesture images. The effectiveness of the proposed technique is evaluated using leave-one-subject-out cross-validation (LOO CV) and regular CV tests on two benchmark datasets. A real-time American sign language (ASL) recognition system is developed and tested using the proposed technique.

Background and purposeThe pathophysiologic basis of posterior reversible encephalopathy syndrome (PRES) remains controversial. Hypertension (HTN)-induced autoregulatory failure with subsequent hyperperfusion is the leading hypothesis, whereas alternative theories suggest vasoconstriction-induced hypoperfusion as the underlying mechanism. Studies using contrast-based CT and MR perfusion imaging have yielded contradictory results supporting both ideas. This work represents one of the first applications of arterial spin labeling (ASL) to evaluate cerebral blood flow (CBF) changes in PRES.Materials and methodsAfter obtaining Institutional Review Board approval, MRI reports at our institution from 07/2015 to 09/2020 were retrospectively searched and reviewed for mention of "PRES" and "posterior reversible encephalopathy syndrome." Of the resulting 103 MRIs (performed on GE 1.5 Tesla or 3 Tesla scanners), 20 MRIs in 18 patients who met the inclusion criteria of clinical and imaging diagnosis of PRES and had diagnostic-quality pseudocontinuous ASL scans were included. Patients with a more likely alternative diagnosis, technically non-diagnostic ASL, or other intracranial abnormalities limiting assessment of underlying PRES features were excluded. Perfusion in FLAIR-affected brain regions was qualitatively assessed using ASL and characterized as hyperperfusion, normal, or hypoperfusion. Additional quantitative analysis was performed by measuring average gray matter CBF in abnormal versus normal brain regions.ResultsHTN was the most common PRES etiology (65%). ASL showed hyperperfusion in 13 cases and normal perfusion in 7 cases. A hypoperfusion pattern was not identified. Quantitative analysis of gray matter CBF among patients with visually apparent hyperperfusion showed statistically higher perfusion in affected versus normal appearing brain regions (median CBF 100.4ml/100g-min vs. 61.0ml/ 100g-min, p&nbsp

Dans cet article, nous montrons que l’utilisation de la représentation corporelle est influencée par des facteurs externes et notamment des facteurs discursifs, comme le type de discours et l’intention pragmatique du locuteur. Cette démonstration prend source dans l’analyse de 18 discours narratifs et 18 discours descriptifs, produits en langue de signes québécoise (LSQ) par trois groupes de signeurs sourds : des signeurs natifs de la langue des signes québécoise (LSQ-L1), des signeurs non natifs de la LSQ ayant la langue des signes américaine comme L1 (LSQ-L2), et des signeurs natifs de la langue des signes américaine (ASL-L1). Nous décrivons l’utilisation de la représentation corporelle dans le discours LSQ, en regard de trois caractéristiques propres à ce phénomène (forme de la représentation corporelle, type de marqueurs, fonction discursive), et de facteurs de variation propres au contexte (types de discours, langue de production et langue du signeur). Les résultats suggèrent que la variable langue de production n’a pas d’incidence sur l’utilisation des structures de représentation corporelle (forme et type de marqueur) et que la variation dans la présence de structures de représentation corporelle dans le discours, est plutôt explicable par la motivation pragmatique. En effet, une analyse croisée des variables fonction discursive et type de discours montre que la représentation corporelle est davantage utilisée pour l’adhésion dans les discours narratifs et pour la distanciation dans les discours descriptifs. In this article, we demonstrate that the use of embodied action is influenced by external factors and notably by discursive factors, such as types of discourse and the pragmatic intentions of the signers. Our analysis is based on 18 narrative and 18 descriptive discourses, all produced in Langue des signes québécoise (LSQ), produced by three groups of Deaf signers: native signers of LSQ (LSQ-L1), non-native signers of LSQ with ASL as first language (LSQ-L2), native signers of ASL (ASL-L1). The variables considered for this analysis are: 1) discursive types (narrative/descriptive), 2) language produced (LSQ/ASL), 3) signers’ language (L1/L2), 4) frequency of embodied action, 5) forms of embodied action (complete, partial dominant and partial non dominant), 6) embodied action markers (head/body position change, breaks in eye contact with the audience, and uses of facial expressions), and 7) pragmatic functions of perspective shifts (adherence, detachment). The results suggest that the language variable does not have any effect on the frequency, form or type of markers in the use of embodied action and that the frequency is explained by pragmatic motivation. Therefore, the variables of pragmatic functions and discursive types analyzed show that embodied action is used more frequently for adherence in narrative discourses and detachment for the descriptive discourses.

Objectives We investigated the feasibility and reproducibility of free-breathing motion-corrected multiple inversion time (multi-TI) pulsed renal arterial spin labelling (PASL), with general kinetic model parametric mapping, to simultaneously quantify renal perfusion (RBF), bolus arrival time (BAT) and tissue T1. Methods In a study approved by the Health Research Authority, 12 healthy volunteers (mean age, 27.6 ± 18.5 years; 5 male) gave informed consent for renal imaging at 3 T using multi-TI ASL and conventional single-TI ASL. Glyceryl trinitrate (GTN) was used as a vasodilator challenge in six subjects. Flow-sensitive alternating inversion recovery (FAIR) preparation was used with background suppression and 3D-GRASE (gradient and spin echo) read-out, and images were motion-corrected. Parametric maps of RBF, BAT and T1 were derived for both kidneys. Agreement was assessed using Pearson correlation and Bland-Altman plots. Results Inter-study correlation of whole-kidney RBF was good for both single-TI (r2 = 0.90), and multi-TI ASL (r2 = 0.92). Single-TI ASL gave a higher estimate of whole-kidney RBF compared to multi-TI ASL (mean bias, 29.3 ml/min/100 g; p

Arterial spin labeling (ASL) provides absolute quantification of resting tissue cerebral blood flow (CBF) as an entirely noninvasive approach with good reproducibility. As a result of neurovascular coupling, ASL provides a useful marker of resting neuronal activity. Recent ASL studies in individuals at clinical high risk of psychosis (CHR) have reported increased resting hippocampal perfusion compared with healthy controls. Schizotypy refers to the presence of subclinical psychotic-like experiences in healthy individuals and represents a robust framework to study neurobiological mechanisms involved in the extended psychosis phenotype while avoiding potentially confounding effects of antipsychotic medications or disease comorbidity. Here we applied pseudo-continuous ASL to examine differences in resting CBF in 21 subjects with high positive schizotypy (HS) relative to 22 subjects with low positive schizotypy (LS), as determined by the Oxford and Liverpool Inventory of Feelings and Experiences. Based on preclinical evidence that hippocampal hyperactivity leads to increased activity in mesostriatal dopamine projections, CBF in hippocampus, midbrain, and striatum was assessed. Participants with HS showed higher CBF of the right hippocampus compared to those with LS (p 5 .031, family-wise error corrected). No differences were detected in the striatum or midbrain. The association between increased hippocampal CBF and HS supports the notion that hippocampal hyperactivity might be a central characteristic of the extended psychosis phenotype, while hyperactivity in subcortical dopamine pathways may only emerge at a higher intensity of psychotic experiences. Wellcome Trust and the Royal Society

Intracranial chondrosarcoma is a very rare malignant tumor of the central nervous system, and is difficult to preoperatively distinguish from other tumors using conventional imaging techniques. Here, we report the case of a 24-year-old woman who presented with mild headache due to chondrosarcoma in the frontal lobe. Preoperative conventional images showed findings typical of an oligodendroglial tumor. However, high apparent diffusion coefficient (ADC) value and extreme hypoperfusion on arterial spin labeling (ASL) were inconsistent with oligodendroglial tumor characteristics. The tumor was completely removed using a standard surgical procedure. Histologic diagnosis was a conventional (classic) chondrosarcoma. High ADC and hypoperfusion on ASL represented low cellularity and low vascularity within conventional chondrosarcoma, respectively. We discuss the utility of ADC and ASL for the preoperative diagnosis of conventional chondrosarcoma.

While the arbitrariness of the sign has occupied a central space in linguistic theory for a century, counter-evidence to this basic tenet has been mounting. Recent findings from cross-linguistic studies on spoken languages have suggested that, contrary to purely arbitrary distributions of phonological content, languages often exhibit systematic and regular phonological and sub-phonological patterns of form-meaning mappings. To date, studies of distributional tendencies of this kind have not been conducted for signed languages. In an investigation of phoneme distribution in American Sign Language (ASL) and Língua Brasileira de Sinais (Libras), tokens of the claw-5 handshape were extracted and analyzed for whether the handshape contributed to the overall meaning of the sign. The data suggests that distribution of the claw-5 handshape is not randomly distributed across the lexicon, but clusters around six form-meaning patterns: convex-concave, Unitary-elements, non-compact matter, hand-as-hand, touch, and interlocking. Interestingly, feature-level motivations were uncovered as the source of the mappings These findings are considered within a new cognitive framework to better understand how and why sub-morphemic units develop and maintain motivated form-meaning mappings. The model proposed here, Embodied Cognitive Phonology, builds on cognitive and usage-based approaches but incorporates theories of embodiment to address the source of the claw-5 mappings. Embodied Cognitive Phonology provides a unifying framework for understanding the perceived differences in phonological patterning and organization across the modalities. Both language-internal and language-external sources of motivation contribute to the emergence of form-meaning mappings. Arbitrariness is argued to be but one possible outcome from the process of emergence and schematization of phonological content, and exists alongside motivation as a legitimate state of linguistic units of all sizes of complexity. Importantly, because language is dynamic, these states are not fixed, but are in continuous flux, as language users reinvent and reinterpret form and meaning over time. Aunque la arbitrariedad del signo lingüístico ha ocupado un lugar destacado en la teoría lingüística del último siglo, evidencias contrarias a este principio lingüístico no han parado de crecer. Los hallazgos recientes de estudios interlingüísticos sobre lenguas orales sugieren que, al contrario que las distribuciones de contenido fonológico puramente arbitrarias, las lenguas normalmente muestran patrones sistemáticos y regulares de relaciones de forma-significado fonológicos y subfonológicos. Sin embargo, hasta la fecha de hoy no existen estudios de estas tendencias distribucionales para las lenguas de señas. Para investigar la distribución de los fonemas en la lengua de señas americana (ASL por sus siglas en inglés) y en la lengua de señas brasileña (LIBRAS por sus siglas en portugués), se extrajeron y analizaron ejemplos de mano en forma de garra para determinar si la forma de la mano contribuía al significado general del signo. Los datos sugieren que la distribución de la mano en forma de garra no se distribuye de manera aleatoria en el lexicón, sino que se agrupa en torno a seis patrones de forma-significado: convexo-cóncavo, elementos unitarios, materia no compacta, mano como mano, contacto y entrelazamiento. Curiosamente, se descubrió que las motivaciones a nivel de función son la fuente de las relaciones de forma-significado. Estos hallazgos deben ser considerados dentro de un nuevo marco cognitivo para comprender mejor cómo y por qué las unidades submorfémicas desarrollan y mantienen relaciones motivadas de forma-significado. El modelo propuesto aquí, la fonología cognitiva corpórea, se fundamenta en enfoques cognitivos y de lingüística basada en el uso, aunque también incorpora elementos de la teoría corpórea para abordar el origen de las proyecciones semánticas de la mano en forma de garra. La fonología cognitiva corpórea proporciona un marco unificador para comprender las diferencias percibidas en la organización y patrones fonológicos en todas las modalidades. Tanto las fuentes de motivación internas como externas al lenguaje contribuyen al surgimiento de relaciones de forma-significado. Se sostiene que la arbitrariedad no es más que un posible resultado del proceso de emergencia y esquematización del contenido fonológico y existe, junto con la motivación, como un estado legítimo de las unidades lingüísticas de todo tipo de complejidad. Cabe destacar que, ya que el lenguaje es dinámico, estos estados no son fijos, sino que cambian continuamente, ya que los usuarios del lenguaje reinventan y reinterpretan la forma y el significado a lo largo del tiempo.

Cerebral blood flow (CBF) measurements are of high clinical value and can be acquired non-invasively with no radiation exposure using pseudo-continuous arterial spin labeling (ASL). The aim of this study was to evaluate accordance in resting state CBF between ASL (CBFASL) and 15O-water positron emission tomography (PET) (CBFPET) acquired simultaneously on an integrated 3T PET/MR system. The data comprised ASL and dynamic 15O-water PET data with arterial blood sampling of eighteen subjects (eight patients with focal epilepsy and ten healthy controls, age 21 to 61 years). 15O-water PET parametric CBF images were generated using a basis function implementation of the single tissue compartment model. Cortical and subcortical regions were automatically segmented using Freesurfer. Average CBFASL and CBFPET in grey matter were 60 ± 20 and 75 ± 22 mL/100 g/min respectively, with a relatively high correlation (r = 0.78, p < 0.001). Bland-Altman analysis revealed poor agreement (bias = −15 mL/100 g/min, lower and upper limits of agreements = −16 and 45 mL/100 g/min, respectively) with a negative relationship. Accounting for the negative relationship, the width of the limits of agreement could be narrowed from 61 mL/100 g/min to 35 mL/100 g/min using regression-based limits of agreements. Although a high correlation between CBFASL and CBFPET was found, the agreement in absolute CBF values was not sufficient for ASL to be used interchangeably with 15O-water PET. Authors and title in thesis list of papers: Fahlström, M., Appel, L., Danfors, T., Engström, M., Antoni, G., Kumlien, E., Wikström, J., Larsson, E-M., Lubberink, M. Evaluation of pseudo-continuous arterial spin labeling MRI – agreement with 15O-water PET with arterial input function and use of integrated PET/MR

Effective connectivity is commonly assessed using blood oxygenation level-dependent (BOLD) signals. In (Havlicek et al., 2015), we presented a novel, physiologically informed dynamic causal model (P-DCM) that extends current generative models. We demonstrated the improvements afforded by P-DCM in terms of the ability to model commonly observed neuronal and vascular transients in single regions. Here, we assess the ability of the novel and previous DCM variants to estimate effective connectivity among a network of five ROIs driven by a visuo-motor task. We demonstrate that connectivity estimates depend sensitively on the DCM used, due to differences in the modeling of hemodynamic response transients; such as the post-stimulus undershoot or adaptation during stimulation. In addition, using a novel DCM for arterial spin labeling (ASL) fMRI that measures BOLD and CBF signals simultaneously, we confirmed our findings (by using the BOLD data alone and in conjunction with CBF). We show that P-DCM provides better estimates of effective connectivity, regardless of whether it is applied to BOLD data alone or to ASL time-series, and that all new aspects of P-DCM (i.e. neuronal, neurovascular, hemodynamic components) constitute an improvement compared to those in the previous DCM variants. In summary, (i) accurate modeling of fMRI response transients is crucial to obtain valid effective connectivity estimates and (ii) any additional hemodynamic data, such as provided by ASL, increases the ability to disambiguate neuronal and vascular effects present in the BOLD signal.

Objectives Intraoperative magnetic resonance imaging is a unique tool for visualizing structures during resection and/or for updating any kind of neuronavigation that might be hampered as a result of brain shift during surgery. Advanced MRI techniques such as perfusion-weighted imaging have already proven to be important in the initial diagnosis preoperatively, but can also help to differentiate between tumor and surgically induced changes intraoperatively. Commonly used methods to visualize brain perfusion include contrast agent administration and are therefore somewhat limited. One method that uses blood as an internal contrast medium is arterial spin labeling (ASL), which might represent an attractive alternative. Materials and methods Ten healthy volunteers were examined using three different scanners and coils within 1 h (3T Achieva MRI using 32-channel head coil, 1.5T Achieva MRI using a 6-channel head coil, 1.5 Intera Scanner using 2 surface coils, Philips, Best, The Netherlands) and quantitative CBF values were calculated and compared between the different setups. Additionally, in eight patients with glioblastoma multiforme, ASL was used pre-, intra-, and postoperatively to define tumor tissue and the extent of resection in comparison to structural imaging. Results A high correlation (r = 0.91–0.96) was found between MRI scanners and coils used. ASL was as reliable as conventional MR imaging if complete resection was already achieved, but additionally provided valuable information regarding residual tumor tissue in one patient. Conclusions Intraoperative arterial spin-labeling is a feasible, reproducible, and reliable tool to map CBF in brain tumors and seems to give beneficial information compared to conventional intraoperative MR imaging in partial resection., Highlights • The use of arterial spin labeling intraoperatively during neurosurgical interventions is presented. • Reproducibility and comparability using various field strengths were successfully proven in a volunteer cohort. • Detection of residual tumor in patients was compared to contrast-enhanced imaging. • Residual tumor could be identified with a high accuracy.

Objective Cerebral blood flow (CBF) plays a critical role in the maintenance of neuronal integrity, and CBF alterations have been linked to deleterious white matter changes. Although both CBF and white matter microstructural alterations have been observed within the context of traumatic brain injury (TBI), the degree to which these pathological changes relate to one another and whether this association is altered by time since injury have not been examined. The current study therefore sought to clarify associations between resting CBF and white matter microstructure post-TBI. Methods 37 veterans with history of mild or moderate TBI (mmTBI) underwent neuroimaging and completed health and psychiatric symptom questionnaires. Resting CBF was measured with multiphase pseudocontinuous arterial spin labeling (MPPCASL), and white matter microstructural integrity was measured with diffusion tensor imaging (DTI). The cingulate cortex and cingulum bundle were selected as a priori regions of interest for the ASL and DTI data, respectively, given the known vulnerability of these regions to TBI. Results Regression analyses controlling for age, sex, and posttraumatic stress disorder (PTSD) symptoms revealed a significant time since injury × resting CBF interaction for the left cingulum (p, Highlights • Oftentimes unconsidered are (1) the dynamic relationship between brain variables of interest and (2) how time since injury may factor into brain changes. • Cerebral blood flow (CBF) plays a critical role in the maintenance of neuronal integrity, and CBF alterations have been linked to deleterious white matter (WM) changes. • Although both CBF and WM alterations have been observed within the context of TBI, the degree to which these pathological changes relate to one another has not been examined. • This is especially critical given CBF reductions could serve to exacerbate or contribute to any trauma-induced WM alterations well beyond the time of initial injury. • The current study explored the association between CBF and WM, and the potential influence of time since injury on this relationship in Veterans with history of TBI. • Results showed an interaction between time since injury and CBF of the left cingulate cortex on WM integrity of the left cingulum bundle. • These findings may assist in clarifying mechanisms underlying the poor long-term outcomes observed in those with history of TBI.

Purpose: To assess the impact of the different post‐processing options in the calibration of arterial spin labeling (ASL) data on perfusion quantification and its reproducibility.Theory and Methods: Absolute quantification of perfusion measurements is one of the promises of ASL techniques. However, it is highly dependent on a calibration procedure that involves a complex processing pipeline for which no standardized procedure has been fully established. In this work, we systematically compare the main ASL calibration methods as well as various post‐processing calibration options, using 2 data sets acquired with the most common sequences, pulsed ASL and pseudo‐continuous ASL.Results: Significant and sometimes large discrepancies in ASL perfusion quantification were obtained when using different post‐processing calibration options. Nevertheless, when using a set of theoretically based and carefully chosen options, only small differences were observed for both reference tissue and voxelwise methods. The voxelwise and white matter reference tissue methods were less sensitive to post‐processing options than the cerebrospinal fluid reference tissue method. However, white matter reference tissue calibration also produced poorer reproducibility results. Moreover, it may also not be an appropriate reference in case of white matter pathology.Conclusion: Poor post‐processing calibration options can lead to large errors in perfusion quantification, and a complete description of the calibration procedure should therefore be reported in ASL studies. Overall, our results further support the voxelwise calibration method proposed by the ASL white paper, particularly given the advantage of being relatively simple to implement and intrinsically correcting for the coil sensitivity profile.

Introduction Preclinical studies support investigation of focused ultrasound for breakdown of cerebral pathologies in neurodegenerative conditions including Alzheimer's disease (AD) and Parkinson's disease (PD). Methods A focused transcranial Doppler device with probes (2 MHz, 520 mW/cm2) affixed bilaterally was used to target the hippocampus (AD) or substantia nigra (PD) with functional magnetic resonance imaging navigation for enhanced plaque removal. A total of 22 patients (n = 11 AD, n = 11 PD) underwent 8 consecutive, weekly, 1-hour treatments wherein sleep was encouraged naturally or pharmacologically. Cognitive and motor functioning assessment was carried out using standardized evaluations at baseline and conclusion. Results Of all, 62.5% of patients had one or more improved cognitive scores without data incongruence, 87% had stable or improved fine motor scores, and 87.5% had stable or improved gross motor scores. No adverse events were reported. Discussion The safety of focused transcranial Doppler and possible enhancement in patient functioning were suggested by outcome data.

Summary Patients with germline mutations in the urea-cycle enzyme argininosuccinate lyase (ASL) are at risk for developing neurobehavioral and cognitive deficits. We find that ASL is prominently expressed in the nucleus locus coeruleus (LC), the central source of norepinephrine. Using natural history data, we show that individuals with ASL deficiency are at risk for developing attention deficits. By generating LC-ASL-conditional knockout (cKO) mice, we further demonstrate altered response to stressful stimuli with increased seizure reactivity in LC-ASL-cKO mice. Depletion of ASL in LC neurons leads to reduced amount and activity of tyrosine hydroxylase (TH) and to decreased catecholamines synthesis, due to decreased nitric oxide (NO) signaling. NO donors normalize catecholamine levels in the LC, seizure sensitivity, and the stress response in LC-ASL-cKO mice. Our data emphasize ASL importance for the metabolic regulation of LC function with translational relevance for ASL deficiency (ASLD) patients as well as for LC-related pathologies., Graphical Abstract, Highlights • ASL is expressed in the locus coeruleus (LC) and regulates catecholamine synthesis • LC-ASL deficiency in mice promotes abnormal stress response and seizure sensitivity • LC-ASL deficiency decreases nitric-oxide levels and tyrosine hydroxylase activity • NO donors normalize catecholamine production and rescue LC-ASL deficiency phenotype, Lerner et al. show that ASL is expressed greatly in the nucleus locus coeruleus (LC), where it regulates NO levels. ASL deficiency in the LC of mice results in abnormal response to stress and in increased seizure sensitivity due to decreased TH activity and catecholamine synthesis. NO donors rescue the phenotype in LC-ASL-deficient mice.

Diffusion tensor imaging (DTI) is a sensitive tool for detecting brain tissue microstructural alterations in Parkinson’s disease (PD). Abnormal cerebral perfusion patterns have also been reported in PD patients using arterial spin labeling (ASL) MRI. In this study we aimed to perform a combined DTI and ASL assessment in PD patients within the basal ganglia, in order to test the relationship between microstructural and perfusion alterations. Fifty-two subjects participated in this study. Specifically, 26 PD patients [mean age (SD) = 66.7 (8.9) years, 21 males, median (IQR) Modified Hoehn and Yahr = 1.5 (1–1.6)] and twenty-six healthy controls [HC, mean age (SD) = 65.2 (7.5), 15 males] were scanned with 1.5T MRI. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD) maps were derived from diffusion-weighted images, while cerebral blood flow (CBF) maps were computed from ASL data. After registration to Montreal Neurological Institute standard space, FA, MD, AD, RD and CBF median values were extracted within specific regions of interest: substantia nigra, caudate, putamen, globus pallidus, thalamus, red nucleus and subthalamic nucleus. DTI measures and CBF were compared between the two groups. The relationship between diffusion parameters and CBF was tested with Spearman’s correlations. False discovery rate (FDR)-corrected p-values lower than 0.05 were considered significant, while uncorrected p-values

Background: We first introduced this meta-analysis was to assess the accuracy of arterial spin labeling (ASL) in the differentiating high-grade gliomas (HGG) from brain solitary metastases (BSM). Methods: The PubMed, Web of Knowledge, and Cochrane Libraries and China National Knowledge Infrastructure databases were searched up to August 31, 2018. The pooled weighted sensitivity and specificity, summary receiver operating characteristic curve (SROC), sensitivity analysis, and threshold effect analysis were performed on Stata version 12.0 and Meta-Disc version 1.4. Deeks’ funnel plot asymmetry test was performed to assess publication bias. Results: Of 5 eligible articles, of the 346 lesions from 346 patients, 274 were HGG, and 72 were BSM. The forest pooled sensitivity of 0.88 (95% confidence interval [CI]: 0.65, 0.96) and specificity of 0.85 (95% CI: 0.74, 0.92) of ASL were reported in this meta-analysis. The pooled area under the curve of SROC was 0.92 (95% CI: 0.89, 0.94). Sensitivity analysis demonstrated that the pooled estimates were reliable. No evident publication bias was obtained (P = .38). Conclusion: The parameters derived from ASL with high accuracy in differentiating HGG from BSM. However, results must be interpreted with caution due to the small sample size considered. Large sample prospective studies were necessary to assess and confirm its clinical value.

Although small airways account for the largest fraction of the total conducting airway surfaces, the epithelial fluid and electrolyte transport in small, native airway epithelia has not been well characterized. Investigations have been limited, no doubt, by the complex tissue architecture as well as by its inaccessibility, small dimensions, and lack of applicable assays, especially in human tissues. To better understand how the critically thin layer of airway surface liquid (ASL) is maintained, we applied a "capillary"-Ussing chamber (area ≈1 mm2) to measure ion transport properties of bronchioles with diameters of ~2 mm isolated from resected specimens of excised human lungs. We found that the small human airway, constitutively and concurrently, secretes and absorbs fluid as observed in porcine small airways (50). We found that the human bronchiolar epithelium is also highly anion selective and constitutively secretes bicarbonate ( HCO3- ), which can be enhanced pharmacologically by cAMP as well as Ca2+-mediated agonists. Concurrent secretion and absorption of surface liquid along with HCO3- secretion help explain how the delicate volume of the fluid lining the human small airway is physiologically buffered and maintained in a steady state that avoids desiccating or flooding the small airway with ASL.

The Sign Language Translator is a glove that translates sign language to text and speech in real time. The glove is outfitted with an Arduino Lilypad, an Accelerometer, Flex Sensors and Contact Sensors. Values from these sensors are sent via bluetooth to an iPhone application which predicts and displays the translated gesture. Through the application, users are able to calibrate the glove and view the translation.Team Advisor: Professor Pooria M. YaghiniDepartment of Electrical Engineering and Computer ScienceWebsite:http://projects.eng.uci.edu/projects/asl-communications-device

Aim Disturbances of renal medullary perfusion and metabolism have been implicated in the pathogenesis of kidney disease and hypertension. Furosemide, a loop diuretic, is widely used to prevent renal medullary hypoxia in acute kidney disease by uncoupling sodium metabolism, but its effects on medullary perfusion in humans are unknown. We performed quantitative imaging of both renal perfusion and oxygenation using Magnetic Resonance Imaging (MRI) before and during furosemide. Based on the literature, we hypothesized that furosemide would increase medullary oxygenation, decrease medullary perfusion, but cause minor changes (

Referencias bibliográficas: p. 179-181. Este estudio cuantitativo investigó las posibles ganancias en la adquisición del vocabulario regional como resultado del aprendizaje incidental tras estudiar en el extranjero durante un semestre. Cinco estudiantes universitarios tomaron cursos en un instituto de idiomas en Madrid (España) viviendo con una familia anfitriona durante un semestre, mientras que un grupo de control de cinco participantes continuó sus estudios en XXXX, en los Estados Unidos. Realizaron una encuesta en línea que contenía cuarenta elementos de vocabulario exclusivos para España (majo, mola, guay y similares) tres veces: al principio y al final del programa y después de tres años. Los resultados mostraron que el grupo que viajó a España mejoró de un 21% a un 54.5% de precisión en el vocabulario regional. Esta adquisición se mantuvo bastante estable después de varios años, disminuyendo a un 45%, pero siempre manteniendo alrededor del doble de los resultados obtenidos en la prueba inicial. Abstract: This quantitative study measured the gains in the acquisition of regional vocabulary as a result of incidental learning after studying abroad for one semester. Five college students took courses at a language institute in Madrid (Spain) while living with a host family during a semester, while a control group with five participants continued their studies at Butler University, in the US. They took a survey online that contained forty vocabulary items exclusive to Spain (majo, mola, guayand similar) three times: at the beginning and at the end of the program and after three years. Results indicated that the group who traveled to Spain improved from a 21% to a 54.5% accuracy rate in the regional vocabulary items. This acquisition remained quite stable after a few years, lowering to 45%, but always maintaining around twice the scores obtained in the initial test. Disponible en formato .pdf Sitio web de la revista (Consulta: 02-12-2020)