Previous functional imaging studies that compared activity patterns in older and younger adults during non-linguistic tasks found evidence for two phenomena: older participants usually show more pronounced task-related positive activity in the brain hemisphere that is not dominant for the task and less pronounced negative task-related activity in temporo-parietal and midline brain regions. The combined effects of these phenomena and the impact on word-retrieval, however, have not yet been assessed. We used functional magnetic resonance imaging to explore task-related positive (active task > baseline) and negative activity (baseline > active task) during semantic and phonemic verbal fluency tasks. Increased right-frontal positive activity during the semantic task and reduced negative activity in the right hemisphere during both tasks was associated with reduced performance in older subjects. No substantial relationship between changes in positive and negative activity was observed in the older participants, pointing towards two partially independent but potentially co-occurring processes. Underlying causes of the observed functional network inefficiency during word-retrieval in older adults need to be determined in the future.

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In recent years, diseases of corals caused by opportunistic pathogens have become widespread. How opportunistic pathogens establish on coral surfaces, interact with native microbiota, and cause disease is not yet clear. This study compared the utilization of coral mucus by coral-associated commensal bacteria ("Photobacterium mandapamensis" and Halomonas meridiana) and by opportunistic Serratia marcescens pathogens. S. marcescens PDL100 (a pathogen associated with white pox disease of Acroporid corals) grew to higher population densities on components of mucus from the host coral. In an in vitro coculture on mucus from Acropora palmata, S. marcescens PDL100 isolates outgrew coral isolates. The white pox pathogen did not differ from other bacteria in growth on mucus from a nonhost coral, Montastraea faveolata. The ability of S. marcescens to cause disease in acroporid corals may be due, at least in part, to the ability of strain PDL100 to build to higher population numbers within the mucus surface layer of its acroporid host. During growth on mucus from A. palmata, similar glycosidase activities were present in coral commensal bacteria, in S. marcescens PDL100, and in environmental and human isolates of S. marcescens. The temporal regulation of these activities during growth on mucus, however, was distinct in the isolates. During early stages of growth on mucus, enzymatic activities in S. marcescens PDL100 were most similar to those in coral commensals. After overnight incubation on mucus, enzymatic activities in a white pox pathogen were most similar to those in pathogenic Serratia strains isolated from human mucosal surfaces.

Purpose The patient's perspective of their health is a core component of evidence-based practice (EBP) and person-centered care. Patient-reported outcomes (PROs), captured with PRO measures (PROMs), are the main way of formally soliciting and measuring the patient's perspective. Currently, however, PROs play a relatively small role in mainstream speech-language pathology practice. The purpose of this article is to raise important questions about how PROs could be applied to EBP in speech-language pathology for individuals with communication disorders and to propose preliminary approaches to address some of these questions. Method Based on a narrative review of the literature, this article introduces relevant terminology and broadly describes PRO applications in other health care fields. The article also raises questions related to PRO-informed clinical practice in speech-language pathology. To address some of these questions, the article explores previous research to provide suggestions for clinical administration, interpretation, and future research. Conclusion More routine measurement of subjective health constructs via PROMs—for example, constructs such as effort, participation, self-efficacy, and psychosocial functioning—may improve EBP. More routine use of PROMs could significantly expand the information that is available to clinicians about individual clients and add to the evidence base for the profession of speech-language pathology. However, careful consideration and more research are needed on how to capture and interpret PROs from individuals with cognitive and language disorders.

Axonal outgrowth is generally thought to be controlled by direct interaction of the lead growth cone with guidance cues, and, in trailing axons, by fasciculation with pioneer fibers. Responses of axons and growth cones were examined as cultured retinal ganglion cell (RGC) axons encountered repellent cues. Either contact with cells expressing ephrins or mechanical probing increased the probability of lead growth cone retraction. Lateral extension of filopodia and lamellipodia hundreds of microns behind the lead growth cone was correlated with its collapse. Transmission electron microscopy showed that some of the lateral extensions originate from the pioneer axon, whereas others represent growth cones of defasciculating trailing axons.

Background There is significant variability in poststroke locomotor learning that is poorly understood and affects individual responses to rehabilitation interventions. Cognitive abilities relate to upper extremity motor learning in neurologically intact adults, but have not been studied in poststroke locomotor learning. Objective To understand the relationship between locomotor learning and retention and cognition after stroke. Methods Participants with chronic (>6 months) stroke participated in 3 testing sessions. During the first session, participants walked on a treadmill and learned a new walking pattern through visual feedback about their step length. During the second session, participants walked on a treadmill and 24-hour retention was assessed. Physical and cognitive tests, including the Fugl-Meyer-Lower Extremity (FM-LE), Fluid Cognition Composite Score (FCCS) from the NIH Toolbox -Cognition Battery, and Spatial Addition from the Wechsler Memory Scale-IV, were completed in the third session. Two sequential regression models were completed: one with learning and one with retention as the dependent variables. Age, physical impairment (ie, FM-LE), and cognitive measures (ie, FCCS and Spatial Addition) were the independent variables. Results Forty-nine and 34 participants were included in the learning and retention models, respectively. After accounting for age and FM-LE, cognitive measures explained a significant portion of variability in learning ( R2 = 0.17, P = .008; overall model R2 = 0.31, P = .002) and retention (Δ R2 = 0.17, P = .023; overall model R2 = 0.44, P = .002). Conclusions Cognitive abilities appear to be an important factor for understanding locomotor learning and retention after stroke. This has significant implications for incorporating locomotor learning principles into the development of personalized rehabilitation interventions after stroke.

During communication, conversational partners should offer as much information as is required and relevant. For instance, the statement "Some Xs Y" is infelicitous if one knows that all Xs Y. Do children understand the link between speaker knowledge and utterance strength? In Experiment 1, 5-year-olds (N = 32) but not 4-year-olds (N = 32) reliably connected statements of different logical strength (e.g., "The girl colored all/some of the star") to observers who were fully or partially informed. Four-year-olds' performance improved when observer knowledge could be assessed more easily (Experiment 2a, N = 25) but remained the same in a nonlinguistic version of Experiment 1 that preserved the epistemic requirements of the original study (Experiment 2b, N = 26). These findings have implications for the development of early communicative abilities.