Christine Tong

Visuomotor Rotations of Varying Size and Direction Compete for a Single Internal Model in Motor Working Memory

When participants adapt to equal and opposite visuomotor rotations in close temporal proximity, memory of the 1st is not consolidated. The authors investigated whether this retrograde interference depends on the use of equal and opposite rotations. On Day 1, different groups of participants adapted to a -30 degrees rotation followed 5 min later by rotations of +30 degrees, +60 degrees, or -60 degrees. On Day 2, all groups were retested on the -30 degrees rotation. Either retrograde interference (in groups who adapted to rotations of opposite sign on Day 1) or retrograde facilitation (in the remaining group) was observed. In all groups, learning of the 2nd rotation resulted in unlearning of the first, indicating that all visuomotor rotations compete for common working memory resources.

Learning and recall of incremental kinematic and dynamic sensorimotor transformations

Numerous studies have shown that when people encounter a sudden and novel sensorimotor transformation that alters perceived or actual movement, they gradually adapt and can later recall what they have learned if they encounter the transformation again. In this study, we tested whether retention and recall of learning is also observed when kinematic and dynamic transformations are introduced incrementally such that participants never experience large movement errors. Participants adapted their reaching movements to either a visuomotor rotation of hand position (kinematic transformation) or a rotary viscous force-field applied to the hand (dynamic transformation). These perturbations were introduced either incrementally or instantaneously. Thus, four groups of participants were tested with an incremental and an instantaneous group for both the kinematic and dynamic perturbations. To evaluate retention of learning, participants from all four groups were tested a day later on the same kinematic or dynamic perturbation presented instantaneously (at full strength). As expected, we found that subjects in the instantaneous group retained learning across days. We also found that, for both kinematic and dynamic perturbations, retention was equally good or better when the transformation was introduced incrementally. Because large and clearly detectable movement errors were not observed during adaptation to incremental perturbations, we conclude that such errors are not required for the learning and retention of internal models of kinematic and dynamic sensorimotor transformations.

The Impact of Explicit Values Clarification Exercises in a Patient Decision Aid Emerges After the Decision Is Actually Made Evidence From a Randomized Controlled Trial

Purpose To determine if particular values clarification exercises included in a patient decision aid had discernible impact on postdecisional regret in patients with early-stage prostate cancer. Methods A multicenter randomized controlled trial compared 2 versions of a computerized patient decision aid: only structured information compared to the structured information plus values clarification exercises. Assessments were conducted during the decision aid visit; telephone follow-up interviews were conducted when patients made their decisions with their physician, 3 months after completing treatment, and >1 year later (per a mailing). Outcome measures included the Decisional Conflict Scale, the Preparation for Decision Making Scale, and the Decision Regret Scale. Results A total of 156 patients participated, 75 provided information only and 81 provided information plus values clarification exercises. The groups did not differ significantly on any outcome evaluated at the decision aid visit; in both groups, decisional conflict decreased immediately after using the decision aid. Between-group differences emerged after the decision was actually made. The values clarification exercises group reported higher Preparation for Decision Making Scale scores at the decision follow-up and at the >1-year follow-up. Regret did not differ significantly between groups at the 3-month follow-up but was lower for the values clarification exercises group than for the information group at the >1-year follow-up. Conclusion The results suggest that the values clarification exercises led to better preparation for decision making and to less regret. The impact, however, only emerged after the decision was made.

Information needs of early-stage prostate cancer patients: A comparison of nine countries

BACKGROUND AND PURPOSE Providing information to patients can improve their medical and psychological outcomes. We sought to identify core information needs common to most early-stage prostate cancer patients in participating countries. MATERIAL AND METHODS Convenience samples of patients treated 3-24 months earlier were surveyed in Canada, England, Italy, Germany, Poland, Portugal, Netherlands, Spain, and Turkey. Each participant rated the importance of addressing each of 92 questions in the diagnosis-to-treatment decision interval (essential/desired/no opinion/avoid). Multivariate modelling determined the extent of variance accounted by covariates, and produced an unbiased prediction of the proportion of essential responses for each question. RESULTS Six hundred and fifty-nine patients responded (response rates 45-77%). On average, 35-53 questions were essential within each country; similar questions were essential to most patients in most countries. Beyond cross-country similarities, each country showed wide variability in the number and which questions were essential. Multivariate modelling showed an adjusted R-squared with predictors country, age, education, and treatment group of only 6% of the variance. A core of 20 questions were predicted to be essential to >2/3 of patients. CONCLUSIONS Core information can be identified across countries. However, providing the core should only be a first step; each country should then provide information tailored to the needs of the individual patient.

Relative performance using haptic and/or touch-produced auditory cues in a remote absolute texture identification task

The current study assessed the relative effectiveness with which unimodal tactile, unimodal touch-produced auditory, and bimodal tactile + auditory cues contribute to the performance of an absolute texture identification task via remote touch. The study contributes to our fundamental understanding of the unimodal perception and intersensory integration of multimodal surface texture cues generated during surface exploration with rigid probes. The results also have significant implications for the design of unimodal and multisensory displays for use with teleoperation and virtual environment systems, as it addresses which modality(ies) may be used to most effectively present sensory information about remotely explored surface textures.

The perceived roughness of resistive virtual textures: II. effects of varying viscosity with a force-feedback device

Klatzky and Lederman [2006] have shown that tangential resistive forces may be used to convey roughness in virtual textures using the WingMan force-feedback mouse. Modeling our experiment after this study, we directly examined the effect of viscous resistance on the perceived roughness magnitude of virtual gratings using a PHANTOM. For each virtual grating, the resistance level encountered at the ridges was varied by altering the viscosity coefficient. Perceived roughness systematically increased as the value of the viscosity coefficient was increased. The ridge-to-groove ratio contributed a small additional effect of microgeometry. These results suggest that simple models of viscous resistance may be used to simulate varying levels of surface roughness.

Information for Decision Making by Patients With Early-Stage Prostate Cancer: A Comparison Across 9 Countries

Purpose: To describe decisional roles of patients with early-stage prostate cancer in 9 countries and to compare the information they rated important for decision making (DM). Method: A survey of recently treated patients was conducted in Canada, Italy, England, Germany, Poland, Portugal, Netherlands, Spain, and Turkey. Participants indicated their decisional role in their actual decision and the role they would prefer now. Each participant also rated (essential/desired/no opinion/avoid) the importance of obtaining answers, between diagnosis and treatment decision, to each of 92 questions. For each essential/desired question, participants specified all purposes for that information (to help them: understand/decide/plan/not sure/other). Results: A total of 659 patients participated with country-specific response rates between 58%-77%. Between 83%-96% of each country’s participants recalled actually taking an active decisional role and, in most countries, that increased slightly if they were to make the decision today; there were no significant differences among countries. There was a small reliable difference in the mean number of questions rated essential for DM across countries. More striking, however, was the wide variability within each country: no question was rated essential for DM by even 50% of its participants but almost every question was rated essential by some. Conclusions: Almost all participants from each country want to participate in their treatment decisions. Although there are country-specific differences in the amount of information required, wide variation within each country suggests that information that patients feel is essential or desired for DM should be addressed on an individual basis in all countries.

Information for decision making by post-menopausal women with hormone receptor positive early-stage breast cancer considering adjuvant endocrine therapy

PURPOSE To identify the information that post-menopausal women with hormone-receptor positive, early-stage breast cancer want, to help them decide among six treatment options for adjuvant-endocrine therapy. METHODS We surveyed women with early-stage breast cancer who were eligible for adjuvant endocrine-therapy 3-18 months earlier. Participants rated the importance of getting each of 95 questions answered before this decision is made (options: essential/desired/not important/avoid). For questions rated essential or desired, participants identified the purpose(s) for having the question answered: to help them understand, make the decision, plan, or other. Participants indicated the role they played in their actual decision and the role they would prefer if the decision was made today. They also indicated whether they felt they had had a choice of endocrine therapy treatments. RESULTS 188 of 343 questionnaires were returned (response rate 55%). Mean age was 67 yr (range 38-88 yr); 76% were married, and 39% had secondary school education or less. On average, respondents rated 18 questions (range 0-94) essential for decision making. Each question was rated essential for decision making by ≥ 7% of participants but only 1 question by >50%. Regarding roles, 89% of respondents had participated in their actual decision and would want to again; an additional 9% had not participated in their actual decision but would want to at the time of the survey. The percentage of respondents who felt they had no choice of endocrine therapy treatments varied between centres, 25% vs 41% and 49%. CONCLUSIONS Most patients want to participate in the decision but they vary widely in the amount and which specific details they want to help them make the decision. IMPLICATION The wide variation in questions considered important means the support should be tailored to the needs of the individual patient.