Faculty Bibliography

The degree to which psychological factors are believed to influence the experience of pain has evolved significantly through history. Over the past 100 years, the trend has shifted from a focus on the study of sensory aspects of pain perception to one where psychological factors play a prominent role. Pain is now viewed as a complex subjective experience consisting of sensory, affective, and cognitive components. Psychological presentations of pain are commonly reduced to a differential among Pain Disorder, Somatization Disorder, and Malingering. Limitations in the use of the current DSM-IV-TR diagnostic classifications for pain will lead to changes in the upcoming DSM-V. Psychological testing is becoming increasingly recognized as a valuable evidence-based method for making diagnoses of psychological factors influencing pain presentations. There is a shift from the use of brief measures of pain intensity to multidimensional scales including assessment of affect and perceived functional disability. There is also increased attention to the use of validity scales for assessing symptom exaggeration and other types of response bias. Neuropsychologists, with specialized knowledge and background in evidence based assessment methods, are particularly well equipped to provide valuable input regarding psychological presentations of pain in forensic contexts and in consultation to multidisciplinary treatment teams.

OBJECTIVE: To measure the volume of basal forebrain septal nuclei in patients with temporal lobe epilepsy (TLE) as compared to patients with extratemporal epilepsy and controls. In animal models of TLE, septal lesions facilitate epileptogenesis, while septal stimulation is antiepileptic. METHOD: Subjects were recruited from 2 sites and consisted of patients with pharmacoresistant focal epilepsy (20 with TLE and mesial temporal sclerosis [MTS], 24 with TLE without MTS, 23 with extratemporal epilepsy) and 114 controls. Septal volume was measured using high-resolution MRI in association with newly developed probabilistic septal nuclei maps. Septal volume was compared between subject groups while controlling for relevant factors. RESULTS: Patients with TLE without MTS had significantly larger septal nuclei than patients with extratemporal epilepsy and controls. This was not true for patients with MTS. These results are interpreted with reference to prior studies demonstrating expansion of the septo-hippocampal cholinergic system in animal models of TLE and human TLE surgical specimens. CONCLUSION: Septal nuclei are enlarged in patients with TLE without MTS. Further investigation of septal nuclei and antiepileptic septo-hippocampal neurocircuitry could be relevant to development of new therapeutic interventions such as septal stimulation for refractory TLE.

The overall goals of this study were to test single versus multiple cognitive deficit models of dyslexia (reading disability) at the level of individual cases and to determine the clinical utility of these models for prediction and diagnosis of dyslexia. To accomplish these goals, we tested five cognitive models of dyslexia--two single-deficit models, two multiple-deficit models, and one hybrid model--in two large population-based samples, one cross-sectional (Colorado Learning Disability Research Center) and one longitudinal (International longitudinal Twin Study). The cognitive deficits included in these cognitive models were in phonological awareness, language skill, and processing speed and/or naming speed. To determine whether an individual case fit one of these models, we used two methods: 1) the presence or absence of the predicted cognitive deficits, and 2) whether the individual's level of reading skill best fit the regression equation with the relevant cognitive predictors (i.e., whether their reading skill was proportional to those cognitive predictors.) We found that roughly equal proportions of cases met both tests of model fit for the multiple deficit models (30-36%) and single deficit models (24-28%); hence, the hybrid model provided the best overall fit to the data. The remaining roughly 40% of cases in each sample lacked the deficit or deficits that corresponded with their best-fitting regression model. We discuss the clinical implications of these results for both diagnosis of school-age children and preschool prediction of children at risk for dyslexia.

BACKGROUND:Reading disability (RD) and attention deficit/hyperactivity disorder (ADHD) are comorbid and genetically correlated, especially the inattentive dimension of ADHD (ADHD-I). However, previous research indicates that RD and ADHD enter into opposite gene by environment (G × E) interactions. METHODS:This study used behavioral genetic methods to replicate these opposite G × E interactions in a sample of same-sex monozygotic and dizygotic twin pairs from the Colorado Learning Disabilities Research Center (CLDRC; DeFries et al., 1997) and to test a genetic hypothesis for why these opposite interactions occur. RESULTS:We replicated opposite G × E interactions for RD (bioecological) and ADHD-I (diathesis-stress) with parental education in the same sample of participants. The genetic hypothesis for this opposite pattern of interactions is that only genes specific to each disorder enter into these opposite interactions, not the shared genes underlying their comorbidity. To test this hypothesis, we used single models with an exploratory three-way interaction, in which the G × E interactions for each disorder were moderated by comorbidity. Neither three-way interaction was significant. The heritability of RD did not vary as a function of parental education and ADHD-I. Similarly, the heritability of ADHD-I did not vary as a function of parental education and RD. CONCLUSIONS:We documented opposite G × E interactions in RD and ADHD-I in the same overall twin sample, but the explanation for this apparent paradox remains unclear. Examining specific genes and more specific environmental factors may help resolve the paradox.

The current study examined whether mood-congruent biases in emotion processing extend to epilepsy patients with depressive symptoms and the potentially moderating effects of age of seizure onset on these biases. In addition, we examined associations between depression (Beck Depression Inventory - 2nd Edition; BDI-II) and quality of life (Quality of Life in Epilepsy - 10-item questionnaire; QOLIE-10). Data from 101 epilepsy patients were analyzed, including 61 females and 40 males. Measures included the Comprehensive Affect Testing System - Abbreviated (CATS-A), from which indices of mood-congruent bias were derived. A significant interaction between BDI-II raw scores and age of seizure onset was found for mood-congruent bias scores in the facial affect modality (beta=-0.24, p<.03). Beck Depression Inventory - 2nd Edition raw scores were significantly and positively correlated with quality of life (QOLIE-10; r=.69, p<.01). Results of the current study show that epilepsy patients with an early age of seizure onset may be most at risk for mood-congruent biases when experiencing depressive symptoms and that such symptoms have real-world implications for quality of life for persons living with epilepsy.

Despite decades of cognitive, neuropsychological and neuroimaging studies, it is unclear if letters are identified before word-form encoding during reading, or if letters and their combinations are encoded simultaneously and interactively. Here using functional magnetic resonance imaging, we show that a 'letter-form' area (responding more to consonant strings than false fonts) can be distinguished from an immediately anterior 'visual word-form area' in ventral occipito-temporal cortex (responding more to words than consonant strings). Letter-selective magnetoencephalographic responses begin in the letter-form area approximately 60 ms earlier than word-selective responses in the word-form area. Local field potentials confirm the latency and location of letter-selective responses. This area shows increased high-gamma power for approximately 400 ms, and strong phase-locking with more anterior areas supporting lexico-semantic processing. These findings suggest that during reading, visual stimuli are first encoded as letters before their combinations are encoded as words. Activity then rapidly spreads anteriorly, and the entire network is engaged in sustained integrative processing.

BACKGROUND: Numerous anticonvulsant agents are now available for treating status epilepticus (SE). However, a paucity of data is available to guide clinicians in the initial treatment of seizures or SE. This study describes the current strategies being employed to treat SE in the USA. METHODS: Fifteen American academic medical centers completed a retrospective, multicenter, observational study by reviewing 10-20 of the most recent cases of SE at their institution prior to December 31, 2009. A multivariate analysis was performed to determine factors associated with cessation of seizures. RESULTS: A total of 150 patients were included. Most patients with SE had a seizure disorder (58 %). SE patients required a median of 3 AEDs for treatment. Three quarters of patients received a benzodiazepine as first-line therapy (74.7 %). Phenytoin (33.3 %) and levetiracetam (10 %) were commonly used as the second AED. Continuous infusions of propofol, barbiturate, or benzodiazepine were used in 36 % of patients. Median time to resolution of SE was 1 day and was positively associated with presence of a complex partial seizure, AED non-compliance prior to admission, and lorazepam plus another AED as initial therapy. Prolonged ICU length of stay and topiramate therapy prior to admission were negatively associated with SE resolution. Mortality was higher in patients without a history of seizure (22.2 vs 6.9 %, p = 0.006). CONCLUSIONS: The use of a benzodiazepine followed by an AED, such as phenytoin or levetiracetam, is common as first and second-line therapy for SE and appears to be associated with a shorter time to SE resolution. AED selection thereafter is highly variable. Patients without a history of seizure who develop SE had a higher mortality rate.

Purpose: Despite the reported diagnostic value of the intracarotid amobarbital procedure (IAP) or "Wada test" for determining hemispheric lateralization and memory functioning, it has never undergone formal reliability testing because a prospective test-retest study design is neither feasible nor ethical. However, some patients require repeat testing for clinical purposes, a circumstance that allows for exploration of issues related to reliability. The current investigation sought to: (1) evaluate the frequency of and reasons for repeated IAPs and (2) describe the test-retest reliability of repeated IAPs in a large tertiary epilepsy center. Methods: A 10-year review (2001-2011) of the New York University Langone Medical Center Comprehensive Epilepsy Center patient registry revealed 630 IAPs. Review of medical records identified 20 individuals who underwent two or more IAPs on separate days. Because IAPs repeated due to technical problems should be considered separate from IAPs repeated for other reasons because these IAPs likely included a change in the procedure (e.g., lower medication dose) in an attempt to ameliorate the complication, patients were grouped accordingly. Six patients underwent repeated IAPs due to technical complication and 14 patients underwent a repeated IAP due to other reasons (e.g., unexpected memory outcome, reconsideration of surgery years after a previous surgical work-up in which no surgery was performed, and/or consideration of a second surgery). Given that data obtained from injections ipsilateral to a seizure focus are sometimes considered in a manner clinically different from data obtained from injections contralateral to the seizure focus, memory outcome was classified relative to the side of identified seizure focus. The degree to which language and memory data were consistent across repeated IAPs was examined. Key Findings: Language functioning was consistently lateralized across IAPs in all but one case. Among the six patients who experienced technical problems in the first IAP, three were fully participatory in the second procedure such that valid data were obtained. For the other three, the technical problem recurred with no change in outcome across procedures. Among the 14 patients with repeated IAPs due to other reasons, 79% of the available ipsilateral and 73% of the contralateral pass/fail outcomes were consistent across procedures. No difference between ipsilateral or contralateral injections was observed for the likelihood of a change in results (p = 0.57). Significance: Our data identified overall high reliability for both the ipsilateral and contralateral sides with repeated IAP testing. Results indicated that although patients for whom a correctable technical problem was identified during the IAP may benefit from a repeat study, there is little benefit to repeating the IAP in patients with discordant or unexpected results (i.e., results are not likely to change). These data support the overall reliability of both the language and memory data obtained from the IAP.