The English Sublexical Toolkit: Methods for indexing sound-spelling consistency.

This work introduces the English Sublexical Toolkit, a suite of tools that utilizes an experience-dependent learning framework of sublexical knowledge to extract regularities from the English lexicon. The Toolkit quantifies the empirical regularity of sublexical units in both the reading and spelling directions (i.e., grapheme-to-phoneme and phoneme-to-grapheme) and at multiple grain sizes (i.e., phoneme/grapheme and onset/rime unit size). It can extract multiple experience-dependent regularity indices for words or pseudowords, including both frequency indices (e.g., grapheme frequency) and conditional probability indices (e.g., grapheme-to-phoneme probability). These tools provide (1) superior estimates of the regularities that better reflect the complexity of the sublexical system relative to previously published indices and (2) completely novel indices of sublexical units such as phonographeme frequency (i.e., combined units of individual phonemes and graphemes that are independent of processing direction). We demonstrate that measures from the toolkit explain significant amounts of variance in empirical data (naming of real words and lexical decision), and either outperform or are comparable to the best available consistency measures. The flexibility of the toolkit is further demonstrated by its ability to readily index the probability of different pseudowords pronunciations, and we report that the measures account for the majority of variance in these empirically observed probabilities. Overall, this work provides a framework and resources that can be flexibly used to identify optimal corpus-based consistency measures that help explain reading/spelling behaviors for real and pseudowords.

Pseudoword spelling: insights into sublexical representations and lexical interactions.

ABSTRACTIn this work we introduce a new tool for measuring English spelling-sound consistency, the PG Toolkit, which we use to conduct detailed analyses of pseudoword spellings that provide new insights into the nature of sublexical and lexical representations. There are several key findings: first, sound-spelling consistency measured at two different "grain sizes", phonographeme and onset/rime, each explained unique variance in pseudoword spelling. Second, lexical skill was more related to pseudoword accuracy at the onset/rime level than at the phonographeme level, and individuals who chose more consistent mappings to spell pseudowords tended to have better lexical skill. Finally, no unique contribution of consistency in the reading direction ("feedback") was found after controlling for consistency in the spelling direction. Taken together, the results validate the various measures provided by the PG Toolkit and establish new evidence that supports an interpretation of sublexical processes as operations over hierarchically-structured representations.

The impact of intensive patient education on clinical outcome in a clinic-based migraine population.

OBJECTIVE: To determine whether the addition of patient education to routine medical management improves the clinical status of migraine patients and reduces their utilization of healthcare resources. BACKGROUND: Optimal migraine management typically requires effective patient education. Such education often is difficult to accomplish in the busy clinic setting. METHODS: One hundred consecutive patients with migraine presenting to an university-based headache clinic were randomized to receive or not receive a standardized course of didactic instruction regarding migraine biogenesis and management. The course consisted of 3 classes taught by lay migraineurs who themselves previously had undergone intensive training. All patients were evaluated initially and at 1, 3, and 6 months by a neurologist blinded as to the results of randomization. Clinical variables examined included headache frequency/severity, migraine disability assessment (MIDAS) scores, patient compliance, presence versus absence of analgesic use/overuse, and headache-related unscheduled visits or phone calls. Comparisons were made between baseline findings and findings at the 6-month follow-up visit, with the change in mean MIDAS score serving as the primary outcome variable. RESULTS: At 6 months the group randomized to receive intensive education exhibited a significantly greater reduction in mean MIDAS score than the group randomized to routine medical management only (24 vs. 14 points; P < .05). Those patients also experienced a reduction in mean headache days per month and a greater reduction in functionally incapacitating headache days per month, exhibited less analgesic overuse and need for abortive therapy, were more compliant with prophylactic therapy prescribed, and made fewer headache-related calls to the clinic or unscheduled visits. CONCLUSION: Intensive education of migraine patients by trained lay instructors may convey significant benefit to those patients and reduce their utilization of healthcare resources.

Predictors of a negative response to topiramate therapy in patients with chronic migraine.

OBJECTIVE: To identify variables predictive of a negative response to prophylactic therapy with topiramate in patients with chronic migraine. BACKGROUND: While certain of the newer antiepileptic drugs (AEDs) have emerged as promising or definitely effective therapies for migraine prevention, we continue to lack biologic or clinical variables predictive of treatment response to these or other widely used prophylactic therapies. METHODS: A consecutive series of 170 patients with IHS-defined migraine who were experiencing 15 or more days of headache per month were treated with topiramate according to a uniform dosing protocol. Variables examined for their potential value in predicting treatment response included age, gender, prior experience with prophylactic therapy, prior experience with divalproex sodium specifically, headache frequency and, if present, duration of chronic daily headache (CDH). A positive treatment response was defined as a 50% or greater reduction in headache days during the second treatment month relative to the patient's pretopiramate baseline. Only patients who completed the treatment phase and achieved the 50 mg BID target dose were analyzed (efficacy analysis). Each variable prospectively selected was evaluated in regards to treatment outcome via a paired t-test, and a multiple regression analysis of all variables subsequently was performed. RESULTS: A total of 116 patients completed at least 60 days of treatment and consequently were available for analysis. In the efficacy analysis, 45 (38.8%) of the 116 responded positively to topiramate. Neither age nor gender influenced treatment response. Those patients with CDH of more than 6 months duration, patients who previously had tried and failed more than three prophylactic agents and patients who previously had failed to respond to divalproex sodium were more likely to be nonresponders, but after multiple regression analysis the only statistically significant predictor of a negative treatment response was CDH of more than 6 months duration (P<.001). CONCLUSIONS: Patients with chronic migraine who are treated with topiramate may respond positively at a rate approaching that reported from placebo-controlled trials involving topiramate or other AEDs administered to less severely afflicted migraineurs. Our analysis suggests that patients with chronic migraine least likely to respond to topiramate would be those with extensive and negative previous experience with prophylactic therapy, previous failure to respond to divalproex sodium, CDH, and, most notably, CDH of more than 6 months duration.