Faculty Bibliography

BACKGROUND:Transcranial direct current stimulation (tDCS) has been explored as a potential intervention in Parkinson's disease (PD) and recent studies have shown promising results in cognitive, gait and motor function. However, evidence of efficacy is limited due to small size studies, short treatment periods, lack of standardization of methodologies and other study design limitations. Remotely supervised-tDCS (RS-tDCS) allows "at-home" study participation, potentially easing recruitment, compliance and overall feasibility for clinical studies. OBJECTIVE:Here, we aim to explore preliminary effects of RS-tDCS paired with cognitive training in PD by delivering RS-tDCS neuromodulation at participant's home while still maintaining clinical trial standards. METHODS:This was a prospective, open-label study using RS-tDCS paired with cognitive training. Each PD participant completed 10 tDCS sessions (20-min, 1.5-2.0-mA, bi-hemispheric DLPFC montage, left anodal), over a span of two weeks. All tDCS sessions were supervised in real-time through videoconferencing. Outcomes included the Unified Parkinson's Disease Rating Scale (UPDRS) and Grooved Pegboard Test. RESULTS:All RS-tDCS sessions were well tolerated and completed successfully. Total UPDRS and motor UPDRS-III scores decreased significantly. Pegboard completion time improved significantly for the non-dominant hand. There was a strong positive correlation between the time of the sessions, and motor improvements in UPDRS part-III. CONCLUSION/CONCLUSIONS:RS-tDCS paradigm through a 'telemedicine protocol' holds therapeutic potential for motor symptoms in PD while maximizing compliance and ease of recruitment. Conducting afternoon sessions might be more effective than during the morning. Our paradigm may be influential in designing future studies and facilitating larger and longer duration clinical trials.

Several methods for identifying suboptimal effort on Spanish neuropsychological assessment have been established. The purpose of this retrospective study was to determine whether recognition data from the WHO-AVLT could be employed for determination of malingering in a Spanish-speaking sample. Sixteen subjects in litigation, 25 neurological patients, and 14 healthy controls completed neuropsychological testing. All subjects completed the Test of Memory Malingering (TOMM). Inclusion criteria for neurological patients and controls included performance above the standard TOMM cutoff. Subjects in litigation were classified as probable malingering, through lower than cutoff performance on the TOMM and at least one other performance validity measure. Cut-off scores for classification of malingering were determined based on the number of recognition hits on the WHO-AVLT. The probable malingering group performed significantly worse than both groups on recognition hits. A score <10 was determined to be the optimal group cutoff, with 56.25% sensitivity and specificity greater than 92%. A combination score of 14 increased sensitivity to 68.75%. These findings provide initial validation of a new malingering index, based on the number of hits on the WHO-AVLT recognition trial. This index will provide valuable information to neuropsychologists conducting forensic or clinical evaluations on Spanish-speaking individuals.

In this study, we employed a kernel support vector machine to predict epilepsy localization and lateralization for patients with a diagnosis of epilepsy (n = 228). We assessed the accuracy to which indices of verbal memory, visual memory, verbal fluency, and naming would localize and lateralize seizure focus in comparison to standard electroencephalogram (EEG). Classification accuracy was defined as models that produced the least cross-validated error (CVϵ). In addition, we assessed whether the inclusion of norm-based standard scores, demographics, and emotional functioning data would reduce CVϵ. Finally, we obtained class probabilities (i.e., the probability of a particular classification for each case) and produced receiver operating characteristic (ROC) curves for the primary analyses. We obtained the least error assessing localization data with the Gaussian radial basis kernel function (RBF; support vectors = 157, CVϵ = 0.22). There was no overlap between the localization and lateralization models, such that the poorest localization model (the hyperbolic tangent kernel function; support vectors = 91, CVϵ = 0.36) outperformed the strongest lateralization model (RBF; support vectors = 201, CVϵ = 0.39). Contrary to our hypothesis, the addition of norm, demographics, and emotional functioning data did not improve the accuracy of the models. Receiver operating characteristic curves suggested clinical utility in classifying epilepsy lateralization and localization using neuropsychological indicators, albeit with better discrimination for localizing determinations. This study adds to the existing literature by employing an analytic technique with inherent advantages in generalizability when compared to traditional single-sample, not cross-validated models. In the future, class probabilities extracted from these and similar analyses could supplement neuropsychological practice by offering a quantitative guide to clinical judgements.

OBJECTIVE:Cognitive impairment is a common symptom of multiple sclerosis (MS) that can lead to declines in daily functioning. Timed instrumental activities of daily living (TIADLs) have been useful to bridge between cognitive testing and real-world functioning in disorders such as Alzheimer's disease and other dementias. However, these have not been standardized for general use, and the tasks that are typically employed have not been sensitive to the detection of milder forms of cognitive deficits. We developed a test of ten TIADLs tasks to measure a broader range of functioning, entitled the "Test of Everyday Cognitive Ability" or TECA, and tested its utility in a diverse sample of participants with MS. METHOD/METHODS:TECA performance was characterized in n = 177 participants with MS and compared to healthy controls (n = 49). A subset from each group received repeated administration. In addition, all participants completed a standard battery of neuropsychological measures. RESULTS:TECA performances were significantly different between MS and control participants. Further, MS participants with cognitive impairment performed significantly slower relative to those MS participants without impairment. CONCLUSIONS:The TECA is a TIADLs assessment appropriate for use in those with MS as it includes a broad range of task difficulties, requires minimum motor involvement, and is sensitive to MS-related cognitive impairment. The TECA is a brief and repeatable test of TIADLs and its ease of administration makes it suitable for both clinical practice and research settings.

Epilepsy is a prevalent condition characterized by variations in its clinical presentation, etiology, and amenability to treatment. Through history, neuropsychologists have played a significant role in performing research studies on changes in language, memory, and executive functioning in patients with epilepsy, including those undergoing surgical treatment for medically refractory seizures. These studies provided a foundation for establishing neuropsychologists as critical members of interdisciplinary clinical teams specializing in evaluation and treatment of epilepsy. This article describes a number of elements of specialized neuropsychological practice that have evolved over the years within a tertiary care epilepsy center. Through diagnostic interview and objective testing, the neuropsychologist is able to provide a more complete and objective understanding of a patient's cognitive and behavioral functioning than what is obtained by other clinicians through brief office visits. While assessment of cognition, mood, and behavior is the most commonly provided service to patients with epilepsy from all age groups, there are many instances when neuropsychologists in surgical settings are called to perform more specialized procedures, including the intracarotid amytal (Wada) procedure, electrocortical stimulation mapping of language eloquent brain regions, and functional brain imaging procedures. While working as a neuropsychologist on an interdisciplinary epilepsy care team requires specialized knowledge and clinical training, it is extremely satisfying due to the diversity of the patient population and the particular challenges resulting from the often unique manner that cognition and behavior can be affected in patients with epilepsy across the lifespan.

[This corrects the article DOI: 10.1371/journal.pone.0177177.].