Non-incremental parsing strategies: the role of short-term working memory

Thesis (M.S.)--Boston UniversityThis study sought to investigate further the findings of Caplan et al. (2011) that heightened self-paced reading [SPR] times may cmrelate positively with comprehension measures at points of significantly increased processing load, indicating use of atypical non-incremental parsing methods. Reading comprehension tasks were presented in SPR and eye-tracking paradigms, and three measures of short-term working memory [ST- WM] were administered. Experimental stimuli consisted of early-closure and late-closure sentences, as the former require the reader to revise his or her initial parse of the sentence at a disambiguating word (creating a point of significantly increased processing load) while the latter do not. Independent variables included WM capacity and sentence type, and dependent variables included self-paced reading time [RT], comprehension accuracy, and five measures of eye fixations: first fixation duration, go past time, dwell time, regression out, and regression in. It was hypothesized that participants would show heightened RT correlating positively with comprehension accuracy at the disambiguating point of the early-closure sentences. It was further predicted that this would correspond with a heightened probability of regression out of the area at this same point. Finally, it was predicted that participants with higher ST-WM capacity would be more likely to show these effects, as they were more likely to use them successfully. No correlation between RT and accuracy was found in the SPR paradigm, and while participants did show heightened probability of regression out of the critical phrase in the early-closure than in the late closure sentences, this phenomenon was also present at nearly all other points in the sentence. A significant interaction between ST-WM capacity and sentence type on RT, such that participants with higher WM capacity showed supra-additively high RT at the critical point in early-closure sentences, was observed. This finding indicates that readers with higher ST-WM capacity may persist in processing sentences longer than their lower ST-WM capacity peers, as argued by Stine-Morrow, Ryan, and Leonard (2000)

The Inner Workings of Working Memory:The Effects of Aging and Language Impairment on Tasks Examining Verbal Working Memory

Wright et al. (2007) tested Persons with Aphasia (PWA) using three N-Back tasks featuring different types of linguistic information - phonological, semantic, and syntactic -- to determine whether Verbal Working Memory (VWM) is a single, united resource. The current study tested three PWA with the same tasks, as well as an additional vision-focused task, to expand on this previous research; two groups of cognitively normal individuals were tested using the same protocol to provide a baseline for comparison. Results from the unimpaired groups indicated no effects of aging, and significant differences in performance across all types of information except phonological and visual cues. Results from PWA were inconclusive. The N-Back task, however, was found to cause misleading patterns in accuracy scores for some tests; sensitivity scores are suggested as a better measure of performance on this testing paradigm

Not enough, or maybe too much: Associative deficit vs. hyper-binding models of aging in implicit learning

Background. This project investigated the effects of cognitive aging on implicit learning [IL] by testing the competing predictions of two models. One model, the Associative Deficit Hypothesis [ADH], suggests that older adults [OAs] have a specific deficit in their ability to form new relationships in memory, whereas the Hyper-Binding Hypothesis [HBH] suggests that age differences in IL stem from attentional changes in later life. Aims. We contrasted the predictions of these models by addressing the following aims: 1. Determine whether OAs show more context dependence in IL tasks than younger adults. 2. Determine whether OAs show greater interference from unattended stimuli during IL tasks than younger adults. Method. We tested context dependence using a novel protocol that manipulated the informativity of objects and their contexts during a word-learning task, and we adapted an established protocol to examine interference from unattended linguistic stimuli. Results. Neither protocol revealed reliable main effects of age on the learning measure, counter to the predictions of both the ADH and the HBH, although this may be a result of relatively small sample sizes and a wide age range in the older age group. Both experiments provided tentative support of the HBH in their higher-order interactions, but some interactions in the interference protocol contradicted elements of the HBH’s predictions. Post-experimental interviews suggested that participants completed the contextual dependence protocol implicitly but may have been explicitly aware of the patterns present in the interference protocol. Future studies should focus on narrowing the age range of older participants and increasing sample sizes, and in the case of the interference protocol, separating effects of different sources of interference (i.e. interference from attended stimuli versus interference from unattended stimuli.

“Posts are my own”: effects of social media disclaimers on perceptions of employees and their organizations from tweets and retweets

PURPOSE – This study empirically assesses the perceptions the public has of employees and their organization following a [re]tweet, and the additional potential ameliorating effect of a disclaimer distancing the organization from the individual employee’s social media presence. DESIGN/METHOD/APPROACH – A fully-crossed 2 (disclaimer v. no disclaimer) × 2 (positive v. negative valence post) × 2 (post v. retweet) experiment exposed participants (N = 173) to an employee’s personal tweet. Resultant perceptions of both the poster (i.e., goodwill) and the poster’s organization (i.e., organizational reputation) were analyzed using planned contrast analyses. FINDINGS – Findings reveal audiences form impressions of individuals based on both tweeted and retweeted content. Perceptions of both the poster’s goodwill and the poster’s organization were commensurate with the valence of the poster’s tweets, stronger when posts were original tweets rather than retweets, and there was a significant interaction effect between valence and [re]tweet. Disclaimers did not significantly affect perceptions, suggesting employers may be better-served by asking employees to omit reference to their employer on their personal social media accounts. ORIGINALITY/VALUE – This research contributes to understanding how employee and organizational reputations are affected by employees’ personal social media content. Results suggest even when a disclaimer explicitly seeks to distance the employee from the organization, audiences still see the employee as informal brand ambassadors of their organization

Psychological distress and unsatisfied need for psychosocial support in adolescent and young adult cancer patients during the first year following diagnosis

Purpose Identifying at‐risk adolescent and young adult (AYA) cancer patients and referring them to age‐appropriate psychosocial support services may be instrumental in reducing psychological distress and promoting psychosocial adaptation. The purpose of this study is to identify trajectories of clinically significant levels of distress throughout the first year following diagnosis and to distinguish factors, including supportive care service use, that predict the extent to which AYAs report distress. Methods In this prospective multisite study, 215 AYAs aged 15–39 years were assessed for psychological distress and psychosocial support service use within the first 4 months of diagnosis and again 6 and 12 months later. On the basis of distress scores, respondents were assigned to one of four distress trajectory groups (Resilient, Recovery, Delayed, and Chronic). Multiple logistic regression analyses examined whether demographics, clinical variables, and reports of unsatisfied need for psychosocial support were associated with distress trajectories over 1 year. Results Twelve percent of AYAs reported clinically significant chronic distress throughout the first 12 months following diagnosis. An additional 15% reported delayed distress. Substantial proportions of AYAs reported that needs for information (57%), counseling (41%), and practical support (39%) remained unsatisfied at 12 months following diagnosis. Not getting counseling needs met, particularly with regard to professional mental health services, was observed to be significantly associated with distress over time. Conclusions Substantial proportions of AYAs are not utilizing psychosocial support services. Findings suggest the importance of identifying psychologically distressed AYAs and addressing their needs for mental health counseling throughout a continuum of care. Copyright © 2014 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109318/1/pon3533.pd

Prevalence and predictors of post‐traumatic stress symptoms in adolescent and young adult cancer survivors: a 1‐year follow‐up study

Objectives Post‐traumatic stress symptoms (PTSS) have been identified as a meaningful indicator of distress in cancer survivors. Distinct from young adult survivors of childhood cancer, young people diagnosed with cancer as adolescents and young adults (AYAs) face unique psychosocial issues; however, there is little published research of PTSS in the AYA population. This study examines prevalence and predictors of PTSS among AYAs with cancer. Methods As part of a longitudinal study of AYAs with cancer, 151 patients aged 15–39 years completed mailed surveys at 6 and 12 months post‐diagnosis. Severity of PTSS was estimated at 6 and 12 months post‐diagnosis. Multiple regression analyses were conducted to investigate the predictive effects of socio‐demographic and clinical characteristics on changes in PTSS over time. Results At 6 and 12 months, respectively, 39% and 44% of participants reported moderate to severe levels of PTSS; 29% had PTSS levels suggestive of post‐traumatic stress disorder. No significant differences in severity of PTSS between 6 and 12 months were observed. Regression analyses suggested that a greater number of side effects were associated with higher levels of PTSS at 6 months. Currently receiving treatment, having surgical treatment, diagnosis of a cancer type with a 90–100% survival rate, remaining unemployed/not in school, and greater PTSS at 6 months were associated with higher levels of PTSS at 12 months. Conclusions Post‐traumatic stress symptoms were observed as early as 6 months following diagnosis and remained stable at 12‐month follow‐up. The development of early interventions for reducing distress among AYA patients in treatment is recommended. Copyright © 2012 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99033/1/pon3217.pd

Adverse birth outcomes in United Republic of Tanzania--impact and prevention of maternal risk factors.

OBJECTIVE: To determine risk factors for poor birth outcome and their population attributable fractions. METHODS: 1688 women who attended for antenatal care were recruited into a prospective study of the effectiveness of syphilis screening and treatment. All women were screened and treated for syphilis and other reproductive tract infections (RTIs) during pregnancy and followed to delivery to measure the incidence of stillbirth, intrauterine growth retardation (IUGR), low birth weight (LBW) and preterm live birth. FINDINGS: At delivery, 2.7% of 1536 women experienced a stillbirth, 12% of live births were preterm and 8% were LBW. Stillbirth was independently associated with a past history of stillbirth, short maternal stature and anaemia. LBW was associated with short maternal stature, ethnicity, occupation, gravidity and maternal malaria whereas preterm birth was associated with occupation, age of sexual debut, untreated bacterial vaginosis and maternal malaria. IUGR was associated with gravidity, maternal malaria, short stature, and delivering a female infant. In the women who had been screened and treated for syphilis, in between 20 and 34% of women with each outcome was estimated to be attributable to malaria, and 63% of stillbirths were estimated as being attributable to maternal anaemia. Screening and treatment of RTIs was effective and no association was seen between treated RTIs and adverse pregnancy outcomes. CONCLUSION: Maternal malaria and anaemia continue to be significant causes of adverse pregnancy outcome in sub-Saharan Africa. Providing reproductive health services that include treatment of RTIs and prevention of malaria and maternal anaemia to reduce adverse birth outcomes remains a priority

A Video-based End-to-end Pipeline for Non-nutritive Sucking Action Recognition and Segmentation in Young Infants

We present an end-to-end computer vision pipeline to detect non-nutritive sucking (NNS) -- an infant sucking pattern with no nutrition delivered -- as a potential biomarker for developmental delays, using off-the-shelf baby monitor video footage. One barrier to clinical (or algorithmic) assessment of NNS stems from its sparsity, requiring experts to wade through hours of footage to find minutes of relevant activity. Our NNS activity segmentation algorithm solves this problem by identifying periods of NNS with high certainty -- up to 94.0\% average precision and 84.9\% average recall across 30 heterogeneous 60 s clips, drawn from our manually annotated NNS clinical in-crib dataset of 183 hours of overnight baby monitor footage from 19 infants. Our method is based on an underlying NNS action recognition algorithm, which uses spatiotemporal deep learning networks and infant-specific pose estimation, achieving 94.9\% accuracy in binary classification of 960 2.5 s balanced NNS vs. non-NNS clips. Tested on our second, independent, and public NNS in-the-wild dataset, NNS recognition classification reaches 92.3\% accuracy, and NNS segmentation achieves 90.8\% precision and 84.2\% recall

Comparison of Patient- and Practitioner-Reported Toxic Effects Associated With Chemoradiotherapy for Head and Neck Cancer

Agreement between patient- and practitioner-reported toxic effects during chemoradiotherapy for head and neck cancer is unknown. To compare patient-reported symptom severity and practitioner-reported toxic effects among patients receiving chemoradiotherapy for head and neck cancer. Forty-four patients participating in a phase 2 trial of deintensified chemoradiotherapy for oropharyngeal carcinoma were included in the present study (conducted from February 8, 2012, to March 2, 2015). Most treatment (radiotherapy, 60 Gy, with concurrent weekly administration of cisplatin, 30 mg/m2) was administered at academic medical centers. Included patients had no prior head and neck cancers, were 18 years or older, and had a smoking history of 10 pack-years or less or more than 10 pack-years but 30 pack-years or less and abstinent for the past 5 years. Cancer status was untreated human papillomavirus or p16-positive squamous cell carcinoma of the oropharynx or unknown head and neck primary site; and cancer staging was category T0 to T3, category N0 to N2c, M0, and Eastern Cooperative Oncology Group performance status 0 to 1. Baseline, weekly, and posttreatment toxic effects were assessed by physicians or nurse practitioners using National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE), version 4.0. Patient-reported symptom severity was measured using the Patient-Reported Outcomes version of the CTCAE (PRO-CTCAE). Descriptive statistics were used to characterize raw agreement between CTCAE grades and PRO-CTCAE severity ratings. Baseline, weekly, and posttreatment toxic effects assessed using CTCAE, version 4.0, and PRO-CTCAE. Raw agreement indices between patient-reported toxic effects, including symptom frequency, severity, and interference with daily activities (score range, 0 [none] to 4 [very severe]), and practitioner-measured toxic effects, including swallowing, oral pain, and hoarseness (score range, 1 [mild] to 5 [death]). Of the 44 patients included in the analysis (39 men, 5 women; mean [SD] age, 61 [8.4] years), there were 327 analyzable pairs of CTCAE and PRO-CTCAE symptom surveys and no treatment delays due to toxic effects. Patient-reported and practitioner-reported symptom severity agreement was high at baseline when most symptoms were absent but declined throughout treatment as toxic effects increased. Most disagreement was due to lower severity of toxic effects reported by practitioners (eg, from 45% agreement at baseline to 27% at the final week of treatment for pain). This was particularly noted for domains that are not easily evaluated by physical examination, such as anxiety and fatigue (eg, severity of fatigue decreased from 43% at baseline to 12% in the final week of treatment). Practitioner-reported toxic effects are lower than patient self-reports during head and neck chemoradiotherapy. The inclusion of patient-reported symptomatic toxic effects provides information that can potentially enhance clinical management and improve data quality in clinical trials