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Dissociation of classification and recognition in amnesia is widely taken to imply 2 functional systems: an implicit procedural-learning system that is spared in amnesia and an explicit episodic-learning system that is compromised. We argue that both tasks reflect the global similarity of probes to memory. In classification, subjects sort unstudied grammatical exemplars from lures, whereas in recognition, they sort studied grammatical exemplars from lures. Hence, global similarity is necessarily greater in recognition than in classification. Moreover, a grammatical exemplar's similarity to studied exemplars is a nonlinear function of the integrity of the data in memory. Assuming that data integrity is better for control subjects than for subjects with amnesia, the nonlinear relation combined with the advantage for recognition over classification predicts the dissociation of recognition and classification. To illustrate the dissociation of recognition and classification in healthy undergraduates, we manipulated study time to vary the integrity of the data in memory and brought the dissociation under experimental control. We argue that the dissociation reflects a general cost in memory rather than a selective impairment of separate procedural and episodic systems.

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Background: Beta blockers can inhibit tumor growth and metastases, while necroinflammation can enhance these tumor properties.Objective: To determine whether beta blockers and necroinflammatory disease predict tumor recurrence and/or overall survival following potentially curative therapeutic interventions for patients with hepatocellular carcinoma (HCC). Methods:The medical records of 36 adults with non-metastatic HCC who had undergone surgical resections and/or radiofrequency ablation (RFA) were retrospectively reviewed. In addition to post-intervention beta blocker usage and serum alanine aminotransferase levels greater than 2xULN, other variables commonly associated with recurrences such as number and size of tumors, state of differentiation and vascular invasion were included in univariate and multivariate analyses for recurrence and survival.Results: Vascular invasion (OR 29.3, 95% CI 2.6-33.6) and surgical resection (OR 0.19, 95% CI 0.04-0.90) emerged from univariate (p=0.003 and 0.03 respectively) and multivariate (p=0.005 and 0.048 respectively) regression as predictors of tumor recurrence whereas beta blocker usage (OR 0.03, 95% CI 0.04-0.9, p=0.03) and tumor recurrence (OR 6.7, 95% CI 1.6-28.1, p=0.026) correlated with overall survival. Conclusions:Neither beta blocker usage nor serum ALT levels predict HCC recurrences, but beta blocker usage is associated with improved overall survival following potentially curative therapeutic interventions for HCC in adults.

Purpose: The Canadian Association of Radiologists (CAR) Endometriosis Working Group developed a national survey to evaluate current practice patterns associated with imaging endometriosis using advanced pelvic ultrasound and MRI to inform forthcoming clinical practice guidelines for endometriosis imaging. Methods: The anonymous survey consisted of 36 questions and was distributed electronically to CAR members. The survey contained a mix of multiple choice, Likert scale and open-ended questions intended to collect information about training and certification, current practices and protocols associated with imaging endometriosis, opportunities for quality improvement and continuing professional development. Descriptive statistics were used to summarize the results. Results: Canadian radiologists were surveyed about their experience with imaging endometriosis. A total of 89 responses were obtained, mostly from Ontario and Quebec. Most respondents were community radiologists, and almost 33% were in their first five years of practice. Approximately 38% of respondents reported that they or their institution performed advanced pelvic ultrasound for endometriosis, with most having done so for less than 5 years, and most having received training during residency or fellowship. 70% of respondents stated they currently interpret pelvic endometriosis MRI, with most having 1-5 years of experience. Conclusion: Many radiologists in Canada do not perform dedicated imaging for endometriosis. This may be due to a lack of understanding of the benefits and limited access to training. However, dedicated imaging can improve patient outcomes and decrease repeated surgeries. The results highlight the importance of developing guidelines for these imaging techniques and promoting a multidisciplinary approach to endometriosis management.