Faculty Bibliography

OBJECTIVE: For patients with medically intractable focal epilepsy, the benefit of epilepsy surgery must be weighed against the risk of cognitive decline. Clinical factors such as age and presurgical cognitive level partially predict cognitive outcome; yet, little is known about the role of cross-hemispheric white matter pathways in supporting postsurgical recovery of cognitive function. The purpose of this study is to determine whether the presurgical corpus callosum (CC) midsagittal area is associated with pre- to postsurgical change following epilepsy surgery. METHODS: In this observational study, we retrospectively identified 24 adult patients from an epilepsy resection series who completed preoperative high-resolution T1 -weighted magnetic resonance imaging (MRI) scans, as well as pre- and postsurgical neuropsychological testing. The total area and seven subregional areas of the CC were measured on the midsagittal MRI slice using an automated method. Standardized indices of auditory-verbal working memory and delayed memory were used to probe cognitive change from pre- to postsurgery. CC total and subregional areas were regressed on memory-change scores, after controlling for overall brain volume, age, presurgical memory scores, and duration of epilepsy. RESULTS: Patients had significantly reduced CC area relative to healthy controls. We found a positive relationship between CC area and change in working memory, but not delayed memory; specifically, the larger the CC, the greater the postsurgical improvement in working memory (beta = 0.523; p = 0.009). Effects were strongest in posterior CC subregions. There was no relationship between CC area and presurgical memory scores. SIGNIFICANCE: Findings indicate that larger CC area, measured presurgically, is related to improvement in working memory abilities following epilepsy surgery. This suggests that transcallosal pathways may play an important, yet little understood, role in postsurgical recovery of cognitive functions.

OBJECTIVE: The Standardized Assessment of Concussion (SAC) is a standardized mental status screening instrument initially developed for assessment and tracking of concussion symptoms in athletes. The purpose of the current study was to validate the utility of the SAC as an embedded screening measure for insufficient effort in independent medical examinations (IME) and personal injury cases. METHOD: A known-groups design was used to examine the SAC's utility for the detection of insufficient effort in 75 de-identified private IME and civil litigation evaluations. Initial classifications of insufficient effort were made independently of SAC scores, on the basis of having two or more scores falling below established cut-offs on previously validated neuropsychological measures. RESULTS: Results suggest that the total score on the SAC significantly distinguishes effortful respondents from those exhibiting insufficient effort. Empirically derived cut-off scores yielded adequate sensitivity (.62-.95) and negative predictive power (.93-.97). CONCLUSIONS: While optimal cut-off scores depend upon intended use, our data suggest that the SAC is useful as a potential screener for insufficient effort, after which one can employ additional measures to rule out false-positives. Further research is required before cut-off scores can be recommended for clinical use.

OBJECTIVE: This study investigated the classification accuracy of the Minnesota Multiphasic Personality Inventory-2-Restructured Form validity scales in a sample of disability claimants and civil forensic litigants. METHOD: A criterion-groups design was used, classifying examinees as "Failed Slick Criteria" through low performance on at least two performance validity indices (stand-alone or embedded) and "Passed Slick Criteria." The stand-alone measures included the Test of Memory Malingering and the Dot Counting Test. The embedded indices were extracted from the Wechsler Adult Intelligence Scales Digit Span and Vocabulary subtests, the California Verbal Learning Test-II, and the Wisconsin Card Sorting Test. RESULTS: Among groups classified by primary complaints at the time of evaluation, those alleging neurological conditions were more frequently classified as Failed Slick Criteria than those alleging psychiatric or medical conditions. Among those with neurological or psychiatric complaints, the F-r, FBS-r, and RBS scales differentiated between those who Passed Slick Criteria from those who Failed Slick Criteria. The Fs scale was also significantly higher in the Failed Slick Criteria compared to Passed Slick Criteria examinees within the psychiatric complaints group. CONCLUSIONS: Results indicated that interpretation of scale scores should take into account the examinees' presenting illness. While this study has limitations, it highlights the possibility of different cutoffs depending on the presenting complaints and the need for further studies to cross-validate the results.

Recent acceleration in development of computerized neuropsychological tests and test batteries has led to gains in sophistication, intuitiveness, and capability with concomitant opportunities for greater adoption among practitioners. Advantages attributed to computerized methods (e. g., standardization, large-scale screening, measurement of performance attributes inaccessible by traditional means) enhance prospects for growth. Despite technological improvement and potential benefit to neuropsychological assessment, the regularity with which neuropsychologists utilize computer-based methods remains unsettled. As part of a 10-year follow-up study of neuropsychological test usage practices, we surveyed neuropsychologists' utilization of computerized instruments and investigated practice-related factors that influence computerized test adoption. Respondents were 512 doctorate-level psychologists residing in the United States and Canada (26% usable response rate; 54% female) affiliated with the National Academy of Neuropsychology or the International Neuropsychological Society. Of the 693 distinct instruments reported by respondents, only 6% (n = 40) were computerized, and the average respondent reported rarely using computerized tests. We present the top-ranked computerized instruments and results of correlational analyses, which indicate that fewer years practicing and the youth of respondents associates with increased likelihood of computerized test utilization, along with increased utilization of neuropsychological tests with alternative or parallel forms. Implications for existing and emerging technologies in research and clinical settings are considered.

Despite the importance of diversity variables to the clinical practice of neuropsychology, little is known about neuropsychologists' multicultural assessment practices and perspectives. The current study was the first to survey issues related to neuropsychologists' assessment of minority populations, proficiency in languages other than English, approaches to interpreting the cognitive scores of minorities, and perceived challenges associated with assessing ethnic/racial minority patients. We also surveyed respondents with regard to their own demographic backgrounds, as neuropsychologists who identify as ethnic/racial minorities are reportedly underrepresented in the field. Respondents were 512 (26% usable response rate; 54% female) doctorate-level psychologists affiliated with the International Neuropsychology Society or the National Academy of Neuropsychology who resided in the United States or Canada. Overall, results suggest that lack of appropriate norms, tests, and referral sources are perceived as the greatest challenges associated with assessment of ethnic/racial minorities, that multicultural training is not occurring for some practitioners, and that some are conducting assessments in foreign languages despite limited proficiency. In addition, ethnic/racial minorities appear to be grossly underrepresented in the field of neuropsychology. Findings are discussed in relation to the need for appropriate education and training of neuropsychologists in multicultural issues and the provision of more valid assessments for ethnic/racial minority individuals.

This study examined the degree to which anxiety contributed to inconsistent material-specific memory difficulties among 243 patients with temporal lobe epilepsy from the Multisite Epilepsy Study. Visual memory performance on the Rey Complex Figure Test (RCFT) was poorer for those with high versus low levels of anxiety but was not found to be related to the TLE side. The verbal memory score on the California Verbal Learning Test (CVLT) was significantly lower for patients with left-sided TLE than for patients with right-sided TLE with low anxiety levels but equally impaired for those with high anxiety levels. These results suggest that we can place more confidence in the ability of verbal memory tests like the CVLT to lateralize to left-sided TLE for those with low anxiety levels, but that verbal memory will be less likely to produce lateralizing information for those with high anxiety levels. This suggests that more caution is needed when interpreting verbal memory tests for those with high anxiety levels. These results indicated that RCFT performance was significantly affected by anxiety and did not lateralize to either side, regardless of anxiety levels. This study adds to the existing literature which suggests that drawing-based visual memory tests do not lateralize among patients with TLE, regardless of anxiety levels.

Rationale: For patients with medically intractable focal epilepsy, the best option for achieving seizure control is often surgical resection. In surgical planning, the potential for seizure reduction must be weighed against the risk of cognitive loss. The role that clinical and demographic factors play in predicting cognitive outcome is well established; however, little is known about the role of crosshemispheric white matter in promoting functional reorganization after surgery. In this study we measured the midsagittal crosssectional area of the corpus callosum (CC) on pre-surgical MRI to investigate whether this property is related to changes in working memory following surgery. Methods: A pre- and post-surgical neuropsychological test battery was obtained in 15 patients (9 males/6 females) who underwent temporal (n = 9), frontal (n = 4), temporal and frontal (n = 1) or parietal lobe (n = 1) resective surgery at NYU Langone Medical Center. Pre-surgical whole-brain T1-weighted 3D MRIs were acquired on all participants from the same dedicated research scanner. The midsaggital CC cross-sectional area was delineated and measured automatically on the MRI using 'yuki' (www.nitrc.org/projects/art), an automatic CC segmentation algorithm, described by Ardekani et al. 2012 (Figure 1A). The Working Memory Index (WMI) from the Wechsler Adult Intelligence Scale was used to probe change in concentration/working memory abilities (postsurgical W