abstract: Although there are many forms of organization on the Web, one of the most prominent ways to organize web content and websites are tags. Tags are keywords or terms that are assigned to a specific piece of content in order to help users understand the common relationships between pieces of content. Tags can either be assigned by an algorithm, the author, or the community. These tags can also be organized into tag clouds, which are visual representations of the structure and organization contained implicitly within these tags. Importantly, little is known on how we use these different tagging structures to understand the content and structure of a given site. This project examines 2 different characteristics of tagging structures: font size and spatial orientation. In order to examine how these different characteristics might interact with individual differences in attentional control, a measure of working memory capacity (WMC) was included. The results showed that spatial relationships affect how well users understand the structure of a website. WMC was not shown to have any significant effect; neither was varying the font size. These results should better inform how tags and tag clouds are used on the Web, and also provide an estimation of what properties to include when designing and implementing a tag cloud on a website. / Dissertation/Thesis / M.S. Applied Psychology 2011

No description available.

Few studies have researched writing difficulties in individuals with Autism Spectrum Disorder (ASD) and the factors responsible for such difficulties. The current study sought to examine writing difficulties in individuals with ASD and the contribution of working memory (WM) difficulties. The investigation consisted of five youth formally diagnosed with ASD (under DSM-IV-TR, higher functioning Autistic Disorder or Asperger’s Disorder), and five youth with no formal diagnosis. Participants completed a counterbalanced battery of tests that assessed their written expression and WM abilities. Due to challenges in recruiting enough participants for purposes of quantitative research, the study mainly used a case-study analysis. The study showed that participants with ASD (group with ASD) had more difficulty with writing and WM tasks than participates without ASD (traditionally developing [TD] group). Nonparametric analyses revealed that writing and WM were not related; however, these findings are cautionary due to very low participation numbers in the investigation. Case-study analysis showed that the group with ASD had underdeveloped writing skills notably in the areas of word count, vocabulary, spelling and grammar. Regarding WM abilities, the group with ASD showed variable patterns of difficulty; some had strengths in verbal WM while others did not. Unfortunately, the study could not determine if writing difficulties were specific due to WM or other causes, although it does provide useful information for further investigation. Additional studies investigating the relationship between writing and WM, particularly in individuals with ASD, are encouraged. / Graduate

Cannabis has been used medicinally for millennia, but the cannabinoid (CB) field exploded with the identification of its endogenous receptors and endocannabinoids (eCBs). In vitro experimentation established that eCBs alter synaptic plasticity at presynaptic nerve terminals; however, the characterization of the eCB system (ECS) in vivo remains incomplete. This study aimed to determine the mechanism of in vivo eCB-mediated hippocampal synaptic plasticity and to analyze the effects this plasticity had on spatial working memory (SWM). With in vivo recordings of field excitatory postsynaptic potentials (fEPSPs) in anesthetized mice and rats as well as pharmacological manipulation of the ECS and glutamate receptor antagonism, it was found that eCBs, both anandamide (AEA) and 2-arachnidonyl glycerol (2-AG), caused LTD at hippocampal CA3-CA1 synapses. Induction of eCB-LTD occurs via a sequential activation of cannabinoid type-1 receptor (CB1R) and NR2B-containing NMDA receptor (NR2BR) and is expressed through the endocytosis of AMPA receptors (AMPARs). Increased eCB tone also caused an impairment of SWM for over 24 hours in the Delayed Non-Match-To-Sample (DNMTS) T-maze. This study provides the first evidence that an acute administration of eCB degradative enzyme inhibitors not only produces an in vivo LTD at hippocampal CA3-CA1 synapses that requires CB1R, NR2BR, and AMPAR, but also impairs SWM, a phenomenon also caused by an acute injection of exogenous CBs.

Indiana University-Purdue University Indianapolis (IUPUI) / There is a well-documented bidirectional relationship between pain and cognitive dysfunction, especially working memory. Despite this extensive body of research, the pain–working memory relationship is poorly understood. Pain catastrophizing – exaggerated negative cognitive and emotional responses towards pain – may contribute to working memory deficits by occupying finite, shared cognitive resources, but this has yet to be investigated. The present study sought to clarify the role of pain catastrophizing (assessed as both a trait-level disposition and state-level process) in working memory dysfunction. Healthy undergraduate participants were randomized to an ischemic pain or control task, during which they completed verbal and non-verbal working memory tests. They also completed measures of state- and trait-level pain catastrophizing. Mediation analyses indicated that state-level pain catastrophizing mediated the relationships of pain group to both verbal and non-verbal working memory, such that participants in the pain group (vs. the control group) catastrophized more about their pain, which then resulted in worse verbal and non-verbal working memory performance. In moderated mediation analyses, trait-level pain catastrophizing moderated this mediation effect for both verbal and non-verbal working memory. Those participants in the pain group who reported greater tendency to catastrophize about pain in general exhibited greater catastrophizing in-the-moment during the pain task, thereby leading to worse verbal and non-verbal working memory performance. These results provide evidence for pain catastrophizing as a putative mechanism and moderating factor of working memory dysfunction in pain. Future research should replicate these results in chronic pain samples, investigate other potential mechanisms (e.g., sleep), and develop interventions to ameliorate cognitive dysfunction by targeting pain catastrophizing.

No description available.

In the past decade, the COVIS model (Ashby, Alfonso-Reese, Turken, & Waldron, 1998) has emerged as the only neuropsychological theory for the existence of multiple brain systems for category learning. COVIS postulates that there are two systems, explicit and implicit, which compete against one another. These two systems reply on two discrete networks: explicit, or rule based categorization relies on executive function and working memory while implicit, or information integration categorization is mediated by dopaminergic pathways. The purpose of this pilot study was to further provide evidence for the existence of multiple systems of category learning. In all three experiments, we interrupted feedback processing using a modified Sternberg task. In Experiment 1 and 2, participants were separated into four conditions, rule based (RB) categorization with a short delay between feedback and the modified Sternberg task, RB categorization with a long delay, information integration (II) categorization with a short delay, and II categorization with a long delay. Participants in the RB conditions performed worse than those in the II conditions in Experiment 1 and 2. After determining there was no significant difference between the short and long delay manipulations, only the short delay was used for Experiment 3. Consistent with Experiment 1 and 2, participants in the RB condition performed worse than those in the II condition. Functional near-infrared spectroscopy (fNIRS) technology was also used in Experiment 3 to determine the difference in prefrontal activation between RB and II conditions. Although statistically not significant, across blocks, the difference in prefrontal activation increased.

Anxiety disorders are among the most commonly diagnosed class of mental illness in the United States, and often involve abnormally high levels of stress and social fear. Despite high lifetime prevalence rates, social anxiety disorder (SAD) has remarkably low diagnosis and treatment rates. Furthermore, while individuals with other specific psychiatric disorders tend to exhibit significant neuropsychological deficits, neuropsychological functioning in individuals with SAD remains largely untested. A majority of the few existing studies concerning neuropsychological performance in SAD samples focus on specific functions, and their limited results are highly mixed. The primary objective of this investigation was to provide a more thorough, broad assessment of both auditory and visual working memory as related to psychometrically-defined social anxiety disorder. In addition, this study aimed to help clarify as to whether such deficits are related to the construct of social anxiety, or whether any potential deficits are better explained by generalized state and/or trait (in-the-moment) anxiety. The implications of a deficit in the visual and/or auditory working memory domains are multifaceted. For example, such a deficit may lead to the inability to detect visual cues in social situations. The inability to process these social cues has the potential to exacerbate some SAD- related symptoms, such as fear of humiliation and judgment. Twenty-nine college students completed both phases of this study, including an assessment of state and trait anxiety as well as social phobia and a four-part working memory battery. An analysis of the Phase II data indicates that individual scores on the four measures of both visual and auditory working memory did not relate to trait and/or state anxiety or psychometrically-defined social anxiety.; Thus, it appears that social, generalized trait, and generalized state anxiety do not relate to a neuropsychological deficit in either type of working memory in this sample population. However, we did find a statistical trend suggesting that as social anxiety increased, there was a relative decrease in visual vs. auditory working memory. This statistical trend remained after covarying for state and trait anxiety respectively. Therefore, future research in this area should examine the discrepancy in performance between the auditory and visual working memory domains as it relates to both diagnosed social phobia and psychometrically-defined social anxiety.

The current study dissociated and examined the two primary components of the phonological working memory subsystem – the short-term store and articulatory rehearsal mechanism – in boys with ADHD (n = 18) relative to typically developing boys (n = 15). Word lists of increasing length (2, 4, and 6 words per trial) were presented to and recalled by children following a brief (3 s) interval to assess their phonological short-term storage capacity. Children’s ability to utilize the articulatory rehearsal mechanism to actively maintain information in the phonological short-term store was assessed using word lists at their established memory span but with extended rehearsal times (12 s and 21 s delays). Results indicate that both phonological short-term storage capacity and articulatory rehearsal are impaired or underdeveloped to a significant extent in boys with ADHD relative to typically developing boys, even after controlling for age, SES, IQ, reading ability, and reading speed. Larger magnitude deficits, however, were apparent in short-term storage capacity (ES = 1.15 to 1.98) relative to articulatory rehearsal (ES = 0.47 to 1.02). These findings are consistent with previous reports of deficient phonological short-term memory in boys with ADHD, and suggest that future attempts to develop remedial cognitive interventions for children with ADHD will need to include active components that require children to hold increasingly more information over longer time intervals

The WMC-gF relationship has been attributed to attentional control by some, and to a learning-based account by others. The current study explores inconsistencies in solving structurally-identical problems and how such factors may explain the WMC-gF relationship. Participants completed multiple versions of the same visual-analogies problems, with some problems sharing surface features and others looking vastly different, to test the ability to generalize a rule. In addition, subsequent iterations were shown either immediately after the first presentation, after two intervening items (second presentation), or after at least 10 intervening items (third presentation). Performance on second-presentation items supported both attention and learning-based accounts and performance on third-presentation items supported only a learning-based account. Furthermore, surface similarities interacted with third-presentation item accuracy and WMC, with a stronger relationship for dissimilar looking items. These findings suggest that the ability to learn and generalize rules throughout a task may largely contribute to the WMC-gF relationship.