Faculty Bibliography

The current study examined the relationship between emotional recognition and depression using the Minnesota Multiphasic Personality Inventory, Second Edition (MMPI-2), in a population with epilepsy. Participants were a mixture of surgical candidates in addition to those receiving neuropsychological testing as part of a comprehensive evaluation. Results suggested that patients with epilepsy reporting increased levels of depression (Scale D) performed better than those patients reporting low levels of depression on an index of simple facial recognition, and depression was associated with poor prosody discrimination. Further, it is notable that more than half of the present sample had significantly elevated Scale D scores. The potential effects of a mood-congruent bias and implications for social functioning in depressed patients with epilepsy are discussed

OBJECTIVE: This study is the first to investigate the influence of a symptom-free waiting period (SFWP) on clinical outcome and risk of repeat injury after sport-related concussion. METHODS: This was a prospective, nonrandomized study of 16 624 player seasons from 1999 to 2004, including a cohort of 635 concussed high school and college athletes grouped on the basis of an SFWP or no SFWP observed after their concussion. Clinical outcome in symptoms, cognitive functioning, and postural stability 45 and 90 days postinjury was compared with preinjury baseline. Data on SFWP and same-season repeat concussion were recorded. RESULTS: An SFWP was observed in 60.3% of cases. There were no significant differences between the SFWP and no SFWP groups in acute injury characteristics or clinical outcome with respect to symptom recovery or postinjury performance on formal neuropsychological and balance testing. Most repeat concussions (79.2%) occurred within 10 days of the initial injury. The rate of repeat concussion was actually higher in the SFWP group (6.49%) than the no SFWP group (0.90%) (P < 0.005), but the repeat concussion subgroup's SFWP was 2.82 days shorter (95% confidence interval, 0.61-5.03; P < 0.01) and these athletes resumed participation 3.55 days sooner (95% confidence interval, 0.06-7.04; P < 0.05) than those in the SFWP group in which there was no repeat concussion. CONCLUSION: Our findings suggest that an SFWP did not intrinsically influence clinical recovery or reduce risk of a repeat concussion. The overall risk of same-season repeat concussion seems to be relatively low, but there may be a period of vulnerability that increases risk of repeat concussion during the first 7 to 10 days postinjury. Further study is required to investigate this preliminary finding and help determine whether this risk can be reduced further with specific injury-management strategies

Epidemiological studies suggest that the Hispanic population is at increased risk for neurological disorders. Yet, few assessment measures have been developed for, adapted to, or normalized with Spanish-speakers. The Neuropsychological Screening Battery for Hispanics (NeSBHIS) was developed to address the lack of resources available to this underserved community. Although the NeSBHIS possesses robust construct validity and clinical utility in a community-based sample, these properties remain largely untested in neurological populations. One hundred and twenty-seven Spanish-speaking Hispanic patients with confirmed epilepsy (mean age = 37.8, SD = 13.3) were evaluated using the NeSBHIS. All participants self-identified as 'Hispanic' and immigrated from Spanish-speaking countries. Data were analyzed using confirmatory factor analysis with the a priori assumption that variables would load according to theoretical expectations reported by Ponton and colleagues (2000). The overall model fit indices were in the desired range: Comparative Fit Index = 0.936, Tucker Lewis Index = 0.915, RMSEA = 0.090, and SRMR = 0.069. All NeSBHIS subtests loaded significantly (p < .001) on their respective factors; the standardized loadings were high, ranging from 0.562 to 0.995, with the exception of Block Design (-0.308). Overall, findings suggest that the NeSBHIS has robust construct validity in a neurological sample

Purpose: To examine distributed patterns of language processing in healthy controls and patients with epilepsy using magnetoencephalography (MEG), and to evaluate the concordance between laterality of distributed MEG sources and language laterality as determined by the intracarotid amobarbital procedure (IAP). Methods: MEG was performed in 10 healthy controls using an anatomically constrained, noise-normalized distributed source solution (dynamic statistical parametric map, dSPM). Distributed source modeling of language was then applied to eight patients with intractable epilepsy. Average source strengths within temporoparietal and frontal lobe regions of interest (ROIs) were calculated, and the laterality of activity within ROIs during discrete time windows was compared to results from the IAP. Results: In healthy controls, dSPM revealed activity in visual cortex bilaterally from approximately 80 to 120 ms in response to novel words and sensory control stimuli (i.e., false fonts). Activity then spread to fusiform cortex approximately 160-200 ms, and was dominated by left hemisphere activity in response to novel words. From approximately 240 to 450 ms, novel words produced activity that was left-lateralized in frontal and temporal lobe regions, including anterior and inferior temporal, temporal pole, and pars opercularis, as well as bilaterally in posterior superior temporal cortex. Analysis of patient data with dSPM demonstrated that from 350 to 450 ms, laterality of temporoparietal sources agreed with the IAP 75% of the time, whereas laterality of frontal MEG sources agreed with the IAP in all eight patients. Discussion: Our results reveal that dSPM can unveil the timing and spatial extent of language processes in patients with epilepsy and may enhance knowledge of language lateralization and localization for use in preoperative planning

The Neuropsychological Screening Battery for Hispanics (NeSBHIS) was developed to address the growing need for linguistically appropriate Spanish-language assessment measures. Despite the potential benefits to clinical practice, no prior study has assessed its diagnostic validity in populations with epilepsy. One hundred and fifteen patients with confirmed epilepsy were evaluated via the NeSBHIS; these data were standardized according to age- and education-based norms. Performance decrements were observed in more than 40% of participants on measures of processing speed and naming. Deficits in verbal and visual recall were also exhibited by 29 and 26% of the sample, respectively. No significant differences in test performance emerged between patients with VEEG evidence of left (N=48) versus right (N=24) temporal lobe epilepsy. Although the NeSBHIS is sensitive to the cognitive impairments commonly observed in populations with epilepsy, there are limitations to its ability to identify lateralized neuropsychological impairment in patients with temporal lobe epilepsy

The diagnosis and treatment of mild traumatic brain injury (MTBI)have historically been hampered by an incomplete base of scientific evidence to guide clinicians. One question has been most elusive to clinicians and researchers alike: What is the true natural history of MTBI? Fortunately, the science of MTBI has advanced more in the last decade than in the previous 50 years, and now reaches a maturity point at which the science can drive an evidence-based approach to clinical management. In particular, technological advances in functional neuroimaging have created a powerful bridge between the clinical and basic science of MTBI in humans. Collectively, findings from clinical, basic science, and functional neuroimaging studies now establish a foundation on which to build integrative theories and testable hypotheses around a comprehensive model of MTBI recovery. We review the current scientific literature on postconcussion symptom recovery, neuropsychological outcome, and neurophysiological healing after MTBI. Special emphasis is placed on how the new evidence base can help guide clinicians in the evaluation and management of military-related MTBI

Data from lesion studies suggest that the ability to perceive speech sounds, as measured by auditory comprehension tasks, is supported by temporal lobe systems in both the left and right hemisphere. For example, patients with left temporal lobe damage and auditory comprehension deficits (i.e., Wernicke's aphasics), nonetheless comprehend isolated words better than one would expect if their speech perception system had been largely destroyed (70-80% accuracy). Further, when comprehension fails in such patients their errors are more often semantically-based, than-phonemically based. The question addressed by the present study is whether this ability of the right hemisphere to process speech sounds is a result of plastic reorganization following chronic left hemisphere damage, or whether the ability exists in undamaged language systems. We sought to test these possibilities by studying auditory comprehension in acute left versus right hemisphere deactivation during Wada procedures. A series of 20 patients undergoing clinically indicated Wada procedures were asked to listen to an auditorily presented stimulus word, and then point to its matching picture on a card that contained the target picture, a semantic foil, a phonemic foil, and an unrelated foil. This task was performed under three conditions, baseline, during left carotid injection of sodium amytal, and during right carotid injection of sodium amytal. Overall, left hemisphere injection led to a significantly higher error rate than right hemisphere injection. However, consistent with lesion work, the majority (75%) of these errors were semantic in nature. These findings suggest that auditory comprehension deficits are predominantly semantic in nature, even following acute left hemisphere disruption. This, in turn, supports the hypothesis that the right hemisphere is capable of speech sound processing in the intact brain.