A Dynamic Approach to Recognition Memory

Thesis (Ph.D.) - Indiana University,Psychological and Brain Sciences/Cognitive Science, 2015We argue that taking a dynamic approach to the understanding of memory will lead to advances that are not possible via other routes. To that end, we present a model of recognition memory that specifies how memory retrieval and recognition decisions jointly evolve over time and show that it is able to jointly predict accuracy, response time, and speed-accuracy trade-off functions. The model affords insights into the effects of study time, list length, and instructions. The model leads to a novel qualitative and quantitative test of the source of word frequency effects in recognition, showing that the relatively high distinctiveness of the features of low frequency words provide the best account. We also show how the dynamic model can be extended to account for paradigms like associative recognition and list discrimination, leading to another novel test of the presence of recall-like processes. Associative recognition, list discrimination, recognition of similar foils, and source exclusion are all better explained by the formation of a compound cue rather than recall, although source memory is found to be better modeled by a recall process

Vaginal Microbicide Preferences Among Midwestern Urban Adolescent Women

Purpose The purpose of this study was to assess adolescent women's preferences for specific microbicide characteristics including pregnancy prevention, timing of application, potential for side effects, and whether it targeted human immunodeficiency virus (HIV) or other sexually transmitted infections (STI). Potential differences in microbicide preferences by adolescent age group and behavioral patterns including engaging in sexual intercourse and use of hormonal contraception were examined, as it was hypothesized that as adolescents progress into adulthood and gain sexual experience their preferences in microbicide characteristics may shift. Method Adolescent and young women (N = 405, 56.0% African American; 24.0% Euro-American) between the ages of 14 and 20 (mean = 17.0, SD = 1.8) were recruited from urban community-based clinics. Video-Audio Computer-Assisted Self-Interviews were conducted with the young women, during which they were asked about their preferences regarding the characteristics of hypothetical vaginal microbicides. Conjoint analysis was utilized to determine adolescent women's relative preferences for each microbicide characteristic and intent-to-purchase microbicides based upon a combination of the selected properties. Results Overall, the results suggest adolescent and young women had an ordered preference for a microbicide with (1) no side effects, (2) pregnancy prevention, (3) postcoital application, and (4) protection against HIV. Age and behavioral group conjoint analyses resulted in the same pattern of preferences as those reported for the entire group. However, women having sex and not using hormonal contraception had a stronger preference for postcoital application. Conclusion The findings suggest that young women's ratings of microbicides were sensitive to characteristics such as side effects, pregnancy prevention, and timing of application and should be considered in microbicide development. The conjoint analysis approach is useful in understanding microbicide preferences, and should be utilized with other populations to assess preferences for specific microbicide characteristics

Development and preliminary testing of the psychosocial adjustment to hereditary diseases scale

Background: The presence of Lynch syndrome (LS) can bring a lifetime of uncertainty to an entire family as members adjust to living with a high lifetime cancer risk. The research base on how individuals and families adjust to genetic-linked diseases following predictive genetic testing has increased our understanding of short-term impacts but gaps continue to exist in knowledge of important factors that facilitate or impede long-term adjustment. The failure of existing scales to detect psychosocial adjustment challenges in this population has led researchers to question the adequate sensitivity of these instruments. Furthermore, we have limited insight into the role of the family in promoting adjustment. Methods: The purpose of this study was to develop and initially validate the Psychosocial Adjustment to Hereditary Diseases (PAHD) scale. This scale consists of two subscales, the Burden of Knowing (BK) and Family Connectedness (FC). Items for the two subscales were generated from a qualitative data base and tested in a sample of 243 participants from families with LS. Results: The Multitrait/Multi-Item Analysis Program-Revised (MAP-R) was used to evaluate the psychometric properties of the PAHD. The findings support the convergent and discriminant validity of the subscales. Construct validity was confirmed by factor analysis and Cronbach’s alpha supported a strong internal consistency for BK (0.83) and FC (0.84). Conclusion: Preliminary testing suggests that the PAHD is a psychometrically sound scale capable of assessing psychosocial adjustment. We conclude that the PAHD may be a valuable monitoring tool to identify individuals and families who may require therapeutic interventions

Translations: effects of viewpoint, feature, naming and context on identifying repeatedly copied drawings

We explored the tension between bottom – up and top – down contributions to object recognition in a collaboration between a visual artist and a cognitive psychologist. Initial pictorial renderings of objects and animals from various viewpoints were iteratively copied, and a series of drawings that changed from highly concrete images into highly abstract images was produced. In drawing identification in which sets were shown in reverse order, participants were more accurate, more confident, and quicker to correctly identify the evolving image when it was originally displayed from a canonical viewpoint with all salient features present. In drawing identification in which images were shown in random order, more abstract images could be resolved as a result of previously identifying a more concrete iteration of the same drawing. The results raise issues about the influence of viewpoint and feature on the preservation of pictorial images and about the role of labelling in the interpretation of ambiguous stimuli. In addition, the study highlights a procedure in which visual stimuli can degrade without necessitating a substantial loss of complexity

Vaginal microbicide preferences among midwestern urban adolescent women

Abstract: Purpose The purpose of this study was to assess adolescent women's preferences for specific microbicide characteristics including pregnancy prevention, timing of application, potential for side effects, and whether it targeted human immunodeficiency virus (HIV) or other sexually transmitted infections (STI). Potential differences in microbicide preferences by adolescent age group and behavioral patterns including engaging in sexual intercourse and use of hormonal contraception were examined, as it was hypothesized that as adolescents progress into adulthood and gain sexual experience their preferences in microbicide characteristics may shift. Method Adolescent and young women (N = 405, 56.0% African American; 24.0% Euro-American) between the ages of 14 and 20 (mean = 17.0, SD = 1.8) were recruited from urban communitybased clinics. Video-Audio Computer-Assisted Self-Interviews were conducted with the young women, during which they were asked about their preferences regarding the characteristics of hypothetical vaginal microbicides. Conjoint analysis was utilized to determine adolescent women's relative preferences for each microbicide characteristic and intent-to-purchase microbicides based upon a combination of the selected properties. Results Overall, the results suggest adolescent and young women had an ordered preference for a microbicide with (1) no side effects, (2) pregnancy prevention, (3) postcoital application, and (4) protection against HIV. Age and behavioral group conjoint analyses resulted in the same pattern of preferences as those reported for the entire group. However, women having sex and not using hormonal contraception had a stronger preference for postcoital application. Conclusion The findings suggest that young women's ratings of microbicides were sensitive to characteristics such as side effects, pregnancy prevention, and timing of application and should be considered in microbicide development. The conjoint analysis approach is useful in understanding microbicide preferences, and should be utilized with other populations to assess preferences for specific microbicide characteristics. microbicides | adolescent women | sexuality | conjoint analysis | adolescent health | Keywords: sexual health Article: The search for a woman-initiated prevention method has led to focus on topical microbicides for sexually transmitted infection (STI)/ human immunodeficiency virus (HIV) prevention. Microbicides are substances that may substantially reduce transmission of STI when applied in the vagina or rectum [1]. Some microbicides may also prevent pregnancy, although not all microbicides will be contraceptive [2]. Microbicides are not currently commercially available; products are in various phases of clinical trials [1]. Most microbicides under development are coitus dependent, requiring women to recognize and prepare for sexual situations and be willing to use a product that requires some comfort with touching their genitals [3]. The process of inserting a microbicide into the vagina may be challenging, as the dialogue around young women's sexuality and their bodies is often lacking [4]. Acceptability research, therefore, remains crucial to anticipate and prospectively address the kinds of obstacles previously associated with other female-initiated products, such as the female condom [5] and [6]. For instance, although women enjoyed having more control in using the female condom, they often did not like the size and discomfort associated with use or the inability to use it covertly [6]. Extant microbicide acceptability research with young women has suggested that contraceptive and disease prevention properties, timing of use, and associated side effects are important characteristics [7]. The findings suggest that young women generally prefer both pregnancy and disease prevention in a single product and insertion with an applicator up to 8 hours in advance [8]. In addition, there is a preference for lubricating products [9] and [10] with low amounts of messiness [9] and leakage [8]. Previous research also indicated that relevant potential side effects may impact microbicide use, including yeast infections, vaginal itching, and allergic reactions [7] and [11]. Furthermore, access was an important gauge of acceptability in a group of adolescent women. Women indicated that microbicides should be promoted through "adolescentspecific and girl-specific venues," including women's magazines [7]. There was also a reported desire for microbicides that would be small enough to carry in their pocket, bra, or within cell phone or palm pilot cases, and should be distributed through schools and sexuality education classes [7]. Most young women preferred over-the-counter availability of microbicides, yet stated they would be embarrassed if purchasing the product in the presence of others [7] and [8]. Thus far, microbicide acceptability research with adolescents has been conducted primarily with older adolescents, using individual interview and focus group methodologies [7] [16]. These qualitative methodologies allow for an in-depth assessment of individual as well as relational and age-related issues that may influence microbicide use [13] and [17]. However, social desirability is often a concern when studying stigmatized or socially sensitive issues associated with sexuality [18] and [19]. Past research has shown that using a video-audio computer-assisted self-interview (VACASI) format (participants privately responding to questions on a computer) for presenting survey questions alleviates the tendency for individuals to present themselves positively and answer questions in a socially desirable fashion [20]. In addition, women and adolescents report sensitive behaviors more frequently when questions are asked using computer interviewing techniques than when participating in a face-to-face interview [20], [21] and [22]. Existing microbicide acceptability research with adolescents also often lacks detailed attention to the multiple dimensions that must be considered simultaneously in a decision to try a product such as a microbicide. The addition of quantitative biopsychosocial studies addressing these issues thus complements the existing qualitative microbicide acceptability research [8], [23] and [24]. The purpose of this study was to quantitatively assess, using full-profile ratings based conjoint analysis, preferences for specific microbicide characteristics among a young, urban population of women. Building on the existing literature we chose to assess young women's preferences for pregnancy and STI (including HIV) prevention as well as timing of application and side effect potential. It was hypothesized that as women progress through the adolescent years, their relative preferences for specific microbicide characteristics may change as a function of their age and sexual experience. Methods Study participants Participants were 405 adolescent and young women between the ages of 14 and 20 (mean = 17, SD = 1.8) recruited from community-based urban health clinics in the Midwestern United States in an area with relatively low rates of HIV [25]. See Study procedure After informed consent was received, the young women were given a computer and headphones in a private exam room to begin the questionnaire. The VACASI began with participants being asked to choose one of four possible "guides" whose face and voice were used throughout the VACASI. Guides were young women (approximately 18-20 years old) who were professional actors of varied ethnic appearance and voice. The guides were used to increase young women's level of comfort with the interview [27]. Following the choice of a guide, more information was given about the microbicide and a product sample was shown. The participant was then asked multiple demographic and sexual behaviors questions and presented with microbicide vignettes that asked her to rate the likelihood of buying each microbicide. The self-interviews were completed in English and lasted 25-45 minutes. Participants received $20 compensation for the time and effort involved in completing the questionnaire. The protocols for the entire project were approved by the University's institutional review board

Large Rayleigh number thermal convection: heat flux predictions and strongly nonlinear solutions

We investigate the structure of strongly nonlinear Rayleigh–Bénard convection cells in the asymptotic limit of large Rayleigh number and fixed, moderate Prandtl number. Unlike the flows analyzed in prior theoretical studies of infinite Prandtl number convection, our cellular solutions exhibit dynamically inviscid constant-vorticity cores. By solving an integral equation for the cell-edge temperature distribution, we are able to predict, as a function of cell aspect ratio, the value of the core vorticity, details of the flow within the thin boundary layers and rising/falling plumes adjacent to the edges of the convection cell, and, in particular, the bulk heat flux through the layer. The results of our asymptotic analysis are corroborated using full pseudospectral numerical simulations and confirm that the heat flux is maximized for convection cells that are roughly square in cross section