Utility of automated memory measures in identifying cognitive impairment in adults with epilepsy.

OBJECTIVE: Cognitive impairment is prevalent in epilepsy and often presents at the time of initial diagnosis. This study sought to validate brief, self-administered, iPad-based recognition memory tasks in a sample of patients with epilepsy and to examine their screening utility in identifying patients with cognitive impairment. METHODS: The Words and Faces tests were administered to 145 adult patients with epilepsy along with a neuropsychological battery. Correlation analyses examined the convergent and divergent validity of the Words and Faces tests, and a series of logistic regression analyses examined discriminative ability in identifying patients with and without cognitive impairments on neuropsychological measures. Patient performance was compared to that of a healthy control group (n = 223), and the relationship between the Words and Faces test performance and disease-related variables (i.e., antiepileptic medication burden, seizure lateralization/localization) was examined. RESULTS: The Words and Faces tests were positively correlated with traditional paper-and-pencil neuropsychological measures of episodic memory, with generally moderate to large effect sizes (r > .40), while correlations between the Words and Faces tests and non-memory measures were generally small in magnitude (r < .30). Patients with epilepsy had significantly lower scores on Words and Faces tests compared to healthy controls, and performance was associated with antiepileptic medication burden and seizure localization. The Words and Faces tests demonstrated good predictive accuracy in identifying any cognitive impairment (concordance (c) statistic = .77) and excellent predictive accuracy (c = .85) in identifying patients with impairments on traditional memory measures. The Words and Faces tests also demonstrated reasonable discrimination for impairments in non-memory domains including executive function, language, attention, processing speed, and visuospatial ability (c = .62 -.70). Importantly, the Words and Faces Immediate Index performed just as well as the Total Score (which included delayed memory performance), suggesting a short version of this measure is sufficient for identifying patients with cognitive impairment. CONCLUSIONS: The Words and Faces tests are valid, computerized tools that can be used to screen for memory and other cognitive impairment in adults with epilepsy.

BDNF and COMT, but not APOE, alleles are associated with psychiatric symptoms in refractory epilepsy.

OBJECTIVE: The objective of this study was to determine whether three common genetic polymorphisms [apolipoprotein (APOE) ε4 (rs42938 and rs7412), brain derived neurotrophic factor (BDNF) Met (rs6265), and catechol-O-methyltransferase (COMT) Val (rs4680)] are associated with increased psychiatric symptomatology in individuals with pharmacoresistant epilepsy. METHODS: One hundred forty-eight adults (Mage = 38 years; 53% female) with refractory epilepsy completed self-report measures of mood, anxiety, and/or personality/psychopathology. Mann-Whitney U, t-tests, and Fisher's exact tests were used to determine if APOE4, BDNF Val66Met, or COMT Val158Met are associated with increased psychiatric symptomatology in people with epilepsy. RESULTS: As a group, BDNF Met carriers reported greater symptoms of depression on the Personality Assessment Inventory (PAI) than those without a Met allele (p = 0.004); COMT Val carriers reported greater symptoms on the PAI Schizophrenia (p = 0.007), Antisocial Features (p = 0.04), and Alcohol Problems (p = 0.03) scales than noncarriers. On the individual level, a significantly greater proportion of BDNF Met carriers demonstrated elevated PAI Depression scores compared to those without a Met allele (p = 0.046). There was also a larger proportion of COMT Val carriers with elevated PAI Anxiety scores as compared to those without a Val allele (p = 0.036). SIGNIFICANCE: This retrospective cross-sectional study provides preliminary evidence for a genetic basis of psychiatric comorbidities in epilepsy and suggests that BDNF and COMT may play an important role in the pathophysiology of mental health problems in this vulnerable population.

Deep brain stimulation of the ventral striatal area for poststroke pain syndrome: a magnetoencephalography study.

Poststroke pain syndrome (PSPS) is an often intractable disorder characterized by hemiparesis associated with unrelenting chronic pain. Although traditional analgesics have largely failed, integrative approaches targeting affective-cognitive spheres have started to show promise. Recently, we demonstrated that deep brain stimulation (DBS) of the ventral striatal area significantly improved the affective sphere of pain in patients with PSPS. In the present study, we examined whether electrophysiological correlates of pain anticipation were modulated by DBS that could serve as signatures of treatment effects. We recorded event-related fields (ERFs) of pain anticipation using magnetoencephalography (MEG) in 10 patients with PSPS preoperatively and postoperatively in DBS OFF and ON states. Simple visual cues evoked anticipation as patients awaited a painful (PS) or nonpainful stimulus (NPS) to the nonaffected or affected extremity. Preoperatively, ERFs showed no difference between PS and NPS anticipation to the affected extremity, possibly due to loss of salience in a network saturated by pain experience. DBS significantly modulated the early N1, consistent with improvements in affective networks involving restoration of salience and discrimination capacity. Additionally, DBS suppressed the posterior P2 (aberrant anticipatory anxiety) while enhancing the anterior N1 (cognitive and emotional regulation) in responders. DBS-induced changes in ERFs could potentially serve as signatures for clinical outcomes. NEW & NOTEWORTHY We examined the electrophysiological correlates of pain affect in poststroke pain patients who underwent deep brain stimulation (DBS) targeting the ventral striatal area under a randomized, controlled trial. DBS significantly modulated early event-related components, particularly N1 and P2, measured with magnetoencephalography during a pain anticipatory task, compared with baseline and the DBS-OFF condition, pointing to possible mechanisms of action. DBS-induced changes in event-related fields could potentially serve as biomarkers for clinical outcomes.

Effects of surgical side and site on psychological symptoms following epilepsy surgery in adults.

This retrospective study examined the potential role of side and site of surgery in psychological symptom change after epilepsy surgery and determined the base rate of psychological change at the individual level. Two-hundred twenty-eight adults completed the Personality Assessment Inventory (PAI) before and after temporal (TLR; n=190) or frontal lobe resection (FLR; n=38). Repeated measures ANOVAs with bootstrapping examined differences in psychological outcome as a function of surgical site separately in patients who underwent left- versus right-sided resections. Individual's PAI score changes were then used to determine the prevalence of clinically meaningful postoperative symptom change. Following left-sided resections, there were significant group-by-time interactions on Somatic Complaints, Anxiety, and Anxiety Related Disorders. There was also a trend in this direction on the Depression scale. TLR patients endorsed greater preoperative symptoms than FLR patients on all of these scales, except the Somatic Complaints scale. After surgery, TLR patients reported symptom improvement on all four scales, while scores of FLR patients remained relatively stable over time. Endorsement of Mania-related symptoms increased in both TLR and FLR groups from pre-to post-surgical testing. Following right-sided resections, both groups endorsed symptom improvements on Somatic Complaints, Anxiety, and Depression scales following surgery. In addition, the TLR group endorsed more Mania-related symptoms than the FLR group regardless of time. Patterns of meaningful change in individual patients were generally consistent with group findings, with the most frequent improvements observed following TLR. However, there were a small subset of patients who reported symptom exacerbation after surgery. Our results suggest that surgical lateralization and localization are important factors in postoperative psychological outcome and highlight the importance of considering psychological change at the individual patient level. Further research is needed to identify potential risk factors for symptom exacerbation to aid in preoperative counseling and identify those patients most in need of postoperative psychological surveillance.

Pain anticipatory phenomena in patients with central poststroke pain: a magnetoencephalography study.

Central poststroke pain (CPSP) is characterized by hemianesthesia associated with unrelenting chronic pain. The final pain experience stems from interactions between sensory, affective, and cognitive components of chronic pain. Hence, managing CPSP will require integrated approaches aimed not only at the sensory but also the affective-cognitive spheres. A better understanding of the brain's processing of pain anticipation is critical for the development of novel therapeutic approaches that target affective-cognitive networks and alleviate pain-related disability. We used magnetoencephalography (MEG) to characterize the neural substrates of pain anticipation in patients suffering from intractable CPSP. Simple visual cues evoked anticipation while patients awaited impending painful (PS), nonpainful (NPS), or no stimulus (NOS) to their nonaffected and affected extremities. MEG responses were studied at gradiometer level using event-related fields analysis and time-frequency oscillatory analysis upon source localization. On the nonaffected side, significantly greater responses were recorded during PS. PS (vs. NPS and NOS) exhibited significant parietal and frontal cortical activations in the beta and gamma bands, respectively, whereas NPS (vs. NOS) displayed greater activation in the orbitofrontal cortex. On the affected extremity, PS (vs. NPS) did not show significantly greater responses. These data suggest that anticipatory phenomena can modulate neural activity when painful stimuli are applied to the nonaffected extremity but not the affected extremity in CPSP patients. This dichotomy may stem from the chronic effects of pain on neural networks leading to habituation or saturation. Future clinically effective therapies will likely be associated with partial normalization of the neurophysiological correlates of pain anticipation.

Automated detection of cognitive impairment in clinical practice.

OBJECTIVE: Cognitive impairment is now recognized as an impending public health crisis. About one-third of adults are concerned about their cognition, and the prevalence of objective cognitive impairment is much higher among those with neurological disorders. Existing screening tools are narrowly focused on detecting dementia in older adults and must be clinician-administered and scored, making them impractical for many neurology practices. This study examined the utility of a brief, self-administered, computerized cognitive screening tool, the Brief Assessment of Cognitive Health (BACH), in identifying cognitive impairment in adults. METHODS: 912 adults (ages 18-84) completed BACH and a neuropsychological battery. Multivariable models were developed to provide a BACH index score reflecting the probability of cognitive impairment for individual patients. Predictive accuracy was compared to that of the Montreal Cognitive Assessment (MoCA) in a subset of 160 older adults from a Memory Disorders clinic. RESULTS: The final multivariable model showed good accuracy in identifying cognitively impaired individuals (c = 0·77). Compared to MoCA, BACH had superior predictive accuracy in identifying older patients with cognitive impairment (c = 0·79 vs. 0·67) as well as differentiating those with MCI or dementia from those without cognitive impairment (c = 0·86 vs. c = 0·67). CONCLUSIONS: Results suggest that cognitive impairment can be identified in adults using a brief, self-administered, automated cognitive screening tool, and BACH provides several advantages over existing screeners: self-administered; automatic scoring; immediate results in health record; easily interpretable score; utility in wide range of patients; and flags for treatable factors that may contribute to cognitive complaints (i.e., depression, sleep problems, and stress).

Utility of the Brief Assessment of Cognitive Health (BACH) computerized screening tool in identifying MS-related cognitive impairment.

BACKGROUND: Current guidelines recommend that individuals with MS are screened annually for processing speed deficits, often using the Symbol Digit Modalities Test (SDMT). However, given the heterogeneity of cognitive deficits in individuals with MS, other screening measures that assess a range of cognitive domains are necessary. The current cross-sectional study aimed to examine the ability of the computerized, self-administered Brief Assessment of Cognitive Health (BACH) screening measure to detect the presence of cognitive impairment in adults with MS as determined by performance on a standard neuropsychological test battery. METHODS: Seventy-two individuals with MS completed the BACH and a comprehensive neuropsychological test battery. Receiver operating characteristic (ROC) analyses were conducted to investigate the ability of the BACH to identify cognitively impaired and cognitively intact individuals. ROC analyses were also conducted to compare the ability of the SDMT to discriminate between cognitively intact and cognitively impaired groups as a comparison with the BACH. RESULTS: Cognitive impairment was observed in 56 % of the sample. The BACH showed acceptable ability to discriminate between cognitively intact and cognitively impaired groups (AUC = 0.78). Additionally, the BACH was able to adequately predict cognitive impairment in domains other than processing speed (AUC = 0.71). The SDMT also demonstrated adequate utility in identifying individuals with cognitive impairment (AUC = 0.73); however, the SDMT was not able to adequately predict cognitive impairment in domains other than processing speed (AUC = 0.56). CONCLUSION: The BACH showed adequate ability to detect cognitive impairment in individuals with MS. The BACH was able to identify impairments across various assessed cognitive domains, including individuals with and without processing speed deficits.

Validation of Self-Administered Visual and Verbal Episodic Memory Tasks in Healthy Controls and a Clinical Sample.

This study evaluated the performance characteristics, construct validity, and reliability of two computerized, self-administered verbal and visual recognition memory tests based on the Remember-Know paradigm. Around 250 healthy control participants and 440 patients referred for neuropsychological assessment used an iPad to complete the Words and Faces recognition memory tests before or after concurrent neuropsychological testing. Performance accuracy was high but without ceiling effects. Education, but not age, was related to overall performance for both samples while the influence of gender and race differed across samples. In the clinical sample, overall performance was worse in those patients demonstrating memory impairment on clinical assessment. Words and Faces subtests demonstrated the strongest correlations with neuropsychological measures of verbal and nonverbal memory, respectively. Both showed moderate correlations with processing speed while Faces was also correlated with visuospatial skills. The memory tests showed good test-retest reliability over two testing sessions. These findings demonstrate acceptable psychometric properties in clinical and community samples and suggest that this computerized format is feasible for memory assessment in clinical contexts.

Deep cerebellar stimulation enhances cognitive recovery after prefrontal traumatic brain injury in rodent.

Functional outcome following traumatic brain injury (TBI) varies greatly, with approximately half of those who survive suffering long-term motor and cognitive deficits despite contemporary rehabilitation efforts. We have previously shown that deep brain stimulation (DBS) of the lateral cerebellar nucleus (LCN) enhances rehabilitation of motor deficits that result from brain injury. The objective of the present study was to evaluate the efficacy of LCN DBS on recovery from rodent TBI that uniquely models the injury location, chronicity and resultant cognitive symptoms observed in most human TBI patients. We used controlled cortical impact (CCI) to produce an injury that targeted the medial prefrontal cortex (mPFC-CCI) bilaterally, resulting in cognitive deficits. Unilateral LCN DBS electrode implantation was performed 6 weeks post-injury. Electrical stimulation started at week eight post-injury and continued for an additional 4 weeks. Cognition was evaluated using baited Y-maze, novel object recognition task and Barnes maze. Post-mortem analyses, including Western Blot and immunohistochemistry, were conducted to elucidate the cellular and molecular mechanisms of recovery. We found that mPFC-CCI produced significant cognitive deficits compared to pre-injury and naïve animals. Moreover, LCN DBS treatment significantly enhanced the long-term memory process and executive functions of applying strategy. Analyses of post-mortem tissues showed significantly greater expression of CaMKIIα, BDNF and p75NTR across perilesional cortex and higher expression of postsynaptic formations in LCN DBS-treated animals compared to untreated. Overall, these data suggest that LCN DBS is an effective treatment of cognitive deficits that result from TBI, possibly by activation of ascending, glutamatergic projections to thalamus and subsequent upregulation of thalamocortical activity that engages neuroplastic mechanisms for facilitation of functional re-organization. These results support a role for cerebellar output neuromodulation as a novel therapeutic approach to enhance rehabilitation for patients with chronic, post-TBI cognitive deficits that are unresponsive to traditional rehabilitative efforts.

Neuropsychological outcomes after thalamic deep brain stimulation for essential tremor.

INTRODUCTION: Non-motor DBS outcomes have received little attention in ET relative to PD. This study examines neuropsychological outcomes in ET following thalamic VIM DBS. METHODS: Fifty patients completed neuropsychological evaluations preoperatively and approximately seven months postoperatively. Cognition and mood changes were analyzed at the group level and individual level. Additional associations with treatment, disease, and demographic characteristics were assessed. RESULTS: Significant cognitive decline was not observed at the group level. At the individual level, 46% of patients demonstrated at least subtle overall cognitive decline (≥1SD on at least one test within at least two domains). Mild decline (≥1SD) was seen in 10%-29.17% of patients on individual tests across all cognitive domains, with highest rates in verbal memory. Substantial cognitive decline (≥2SD) occurred in less than 9% of the sample across all tests. Factors related to cognitive decline included higher DBS parameter settings, older age of ET onset, intracranial complications, and inability to reduce ET medications postoperatively. Depression and anxiety did not change when accounting for questionnaire items that could be falsely elevated by tremor. CONCLUSION: Substantial cognitive decline after VIM DBS is rare in patients with ET. However, subtle decrements can occur across cognitive domains and particularly in verbal memory. DBS parameter settings may relate to cognitive decline. Further research is needed to better understand possible associations with electrode lateralization and other variables that could also relate to disease progression and test-retest effects. Symptoms of depression and anxiety remain stable.

Iowa Gambling Task Performance in Parkinson Disease Patients with Impulse Control Disorders.

OBJECTIVE: A subgroup of patients with Parkinson disease (PD) develops impulse control disorders (ICD) associated with their dopamine replacement therapy. Patients and their families may be reluctant to report ICD symptoms or unaware these symptoms are related to PD medication, which can make detecting an ICD difficult for clinicians. Ideally, a behavioral measure that is sensitive to ICD could be employed to ensure that patients with these behaviors are identified and treated. The Iowa Gambling Task (IGT), a standardized decision-making task, has proven sensitive in other populations with impulse control problems. We hypothesized that the IGT would differentiate between PD patients with and without ICD. METHODS: We compared IGT performance and disease variables in 24 PD patients with ICD and 24 PD patients without ICD. Patient groups were matched in terms of age, sex, and duration of PD. RESULTS: There were no significant differences in IGT scores between PD groups. IGT performance declined with increasing age, but the majority of patients performed within normal limits based on published age- and education-corrected normative data. CONCLUSIONS: The IGT did not distinguish between PD patients with and without ICD. Increasing age negatively impacted performance in both groups. Other studies have found that IGT performance may decline in normal aging. Our results suggest that the IGT lacks the sensitivity and specificity needed to differentiate between age-related deficits and disruption in frontal-subcortical circuits underlying ICD associated with PD medications. Therefore, the IGT is not an appropriate behavioral measure for ICD in PD patients.

Validation of computerized episodic memory measures in a diverse clinical sample referred for neuropsychological assessment.

OBJECTIVE: To examine the convergent and discriminant validity of two brief computerized episodic memory measures in a large, diverse clinical sample of adults undergoing neuropsychological assessment. METHOD: Computerized measures of word and face memory were administered to 233 adults (age 30 and over) who also completed comprehensive neuropsychological testing. RESULTS: Moderate correlations were observed between the computerized memory tests and a wide range of traditional neuropsychological measures of episodic memory (e.g. word-list learning, story recall, face recognition, design recall). Select measures of visuomotor processing speed and language were also related to performance on the computerized tasks. In contrast, the computerized memory tests showed weak correlations with tests in other cognitive domains (i.e. visuospatial skills, attention/working memory, executive function, motor dexterity, academic skills) and self-report screening measures of mood and anxiety. Similar to traditional measures of episodic memory, the computerized memory measures were sensitive to effects of age and gender. CONCLUSIONS: Computerized measures of word and face memory showed good convergent and discriminant validity in this diverse clinical sample supporting the construct validity of these measures. This indicates that it may be feasible to measure memory function in clinical settings using brief, well-designed computerized memory measures.

Quality of Life Improvement Following Deep Brain Stimulation for Parkinson Disease: Development of a Prognostic Model.

BACKGROUND: There is a growing attention to determine the factors that predict quality of life (QoL) improvement after deep brain stimulation (DBS) for Parkinson's disease. Prior literature has largely focused on examining predictors one at a time, sometimes controlling for covariates. OBJECTIVE: To develop a model that could be used as a nomogram to predict improvement in QoL following DBS surgery in patients with Parkinson's disease. METHODS: All patients with complete pre- and postoperative movement disorder and neuropsychological testing who underwent DBS at a single institution between 2007-2012 were analyzed. The Parkinson's Disease Questionnaire-39 (PDQ-39) was used to measure QoL. Potential predictive factors, including patient demographics, clinical presentation characteristics, radiographic imaging, and motor and psychological testing were analyzed for impact on QoL. RESULTS: Sixty-seven patients were identified, 36 (53.73%) of whom had meaningfully improved QoL following surgery. Five baseline variables showed significant relationships with the outcome: years since symptom onset, percent change in on/off motor evaluation, levodopa equivalent daily dose, bilateral vs unilateral DBS implantation, and PDQ-39 score. The final model includes PDQ-39, percent change in UPRS-III, and years since symptom onset and is able to predict improvement in QoL with 81% accuracy. CONCLUSION: Our model accurately predicted whether QoL would improve in patients undergoing subthalamic nucleus DBS 81% of the time. Our data may serve as the foundation to further refine a clinically relevant prognostic tool that would assist the decision-making process for clinicians and DBS multidisciplinary teams assessing patient candidacy for surgery.

Predicting early cognitive decline in newly-diagnosed Parkinson's patients: A practical model.

OBJECTIVE: To create a multivariable model to predict early cognitive decline among de novo patients with Parkinson's disease, using brief, inexpensive assessments that are easily incorporated into clinical flow. METHODS: Data for 351 drug-naïve patients diagnosed with idiopathic Parkinson's disease were obtained from the Parkinson's Progression Markers Initiative. Baseline demographic, disease history, motor, and non-motor features were considered as candidate predictors. Best subsets selection was used to determine the multivariable baseline symptom profile that most accurately predicted individual cognitive decline within three years. RESULTS: Eleven per cent of the sample experienced cognitive decline. The final logistic regression model predicting decline included five baseline variables: verbal memory retention, right-sided bradykinesia, years of education, subjective report of cognitive impairment, and REM behavior disorder. Model discrimination was good (optimism-adjusted concordance index = .749). The associated nomogram provides a tool to determine individual patient risk of meaningful cognitive change in the early stages of the disease. CONCLUSIONS: Through the consideration of easily-implemented or routinely-gathered assessments, we have identified a multidimensional baseline profile and created a convenient, inexpensive tool to predict cognitive decline in the earliest stages of Parkinson's disease. The use of this tool would generate prediction at the individual level, allowing clinicians to tailor medical management for each patient and identify at-risk patients for clinical trials aimed at disease modifying therapies.

Contact Location and Neuropsychological Outcomes in Subthalamic Deep Brain Stimulation.

BACKGROUND: A host of influences contribute to cognitive and behavioral changes following deep brain stimulation. The location of the active cathode is likely an important variable but it has received little attention. OBJECTIVE: To determine whether active contact location relative to the subthalamic nucleus and other neighboring structures is related to nonmotor outcomes. METHODS: We identified a retrospective, cross-sectional sample of 46 patients who underwent subthalamic nucleus deep brain stimulation for treatment of idiopathic Parkinson's disease. T-tests or nonparametric equivalents were used to detect baseline differences between unilateral left, unilateral right, and bilateral surgical groups. Correlation and partial correlational analyses identified relationships between contact location variables and alterations in cognitive, mood, quality of life, motor, and disease variables. RESULTS: Medial contact locations within the left subthalamic nucleus were correlated with improvements in self-reported mood (r12 = -0.78, P = .001; 95% confidence interval [CI] = -0.43 to -0.93) but worsening semantic fluency (r26 = -0.38, P = .048; 95% CI = -0.01 to -0.66). Phonemic fluency worsened with more posterior left placement (r34 = 0.35, P = .036; 95% CI = 0.03 to 0.61). Memory outcome was related to right hemisphere stimulation voltage (r29 = -0.40, P = .022; 95% CI = -0.05 to -0.66), which is likely a proxy for variable electrode location. CONCLUSION: Location of the active contact is related to nonmotor outcomes, even in electrodes that are adequately placed. This is relevant to clinical care as there appears to be a trade-off between mood and fluency abilities that should be considered during surgical planning according to preoperative patient characteristics.

Neuropsychological outcome following frontal lobectomy for pharmacoresistant epilepsy in adults.

OBJECTIVE: This retrospective cohort study characterized cognitive and motor outcomes in a large sample of adults who underwent frontal lobe resections for treatment of pharmacoresistant epilepsy. METHODS: Ninety patients who underwent unilateral frontal lobe resection for epilepsy (42 language-dominant hemisphere/48 nondominant hemisphere) between 1989 and 2014 completed comprehensive preoperative and postoperative neuropsychological evaluations that included measures of verbal and nonverbal intellectual functioning, attention/working memory, processing speed, language, executive functioning, verbal and visual memory, and motor functioning. Objective methods were used to assess meaningful change across a wide range of abilities and to identify factors associated with neuropsychological decline following frontal lobectomy. Detailed postoperative neuroimaging analysis was conducted to characterize region, extent, and volume of resection. RESULTS: Forty-eight percent of patients did not demonstrate meaningful postoperative declines in cognition and an additional 42% demonstrated decline in 1 or 2 cognitive domains. When cognitive decline was observed, it usually occurred on measures of intelligence, visuomotor processing speed, or executive functioning. Side and site of resection were unrelated to cognitive outcome, but played a role in decline of contralateral manual dexterity following supplementary motor area resection. Higher preoperative ability, older age at surgery, absence of a malformation of cortical development on MRI, and poor seizure outcome were related to cognitive decline on some measures, but had poor sensitivity in identifying at-risk patients. CONCLUSIONS: The vast majority of patients who undergo frontal lobectomy for treatment of pharmacoresistant epilepsy demonstrate good cognitive and motor outcomes.

Early event related fields during visually evoked pain anticipation.

OBJECTIVE: Pain experience is not only a function of somatosensory inputs. Rather, it is strongly influenced by cognitive and affective pathways. Pain anticipatory phenomena, an important limitation to rehabilitative efforts in the chronic state, are processed by associative and limbic networks, along with primary sensory cortices. Characterization of neurophysiological correlates of pain anticipation, particularly during very early stages of neural processing is critical for development of therapeutic interventions. METHODS: Here, we utilized magnetoencephalography to study early event-related fields (ERFs) in healthy subjects exposed to a 3 s visual countdown task that preceded a painful stimulus, a non-painful stimulus or no stimulus. RESULTS: We found that the first countdown cue, but not the last cue, evoked critical ERFs signaling anticipation, attention and alertness to the noxious stimuli. Further, we found that P2 and N2 components were significantly different in response to first-cues that signaled incoming painful stimuli when compared to non-painful or no stimuli. CONCLUSIONS: The findings indicate that early ERFs are relevant neural substrates of pain anticipatory phenomena and could be potentially serve as biomarkers. SIGNIFICANCE: These measures could assist in the development of neurostimulation approaches aimed at curbing the negative effects of pain anticipation during rehabilitation.

Estimating risk of word-finding problems in adults undergoing epilepsy surgery.

OBJECTIVE: This retrospective, observational study examined the frequency and magnitude of change in naming ability as a function of side/site of epilepsy surgery and identified predictive factors to assist clinicians in identifying patients at low, moderate, or high risk of postoperative naming decline. METHODS: A total of 875 adults with pharmacoresistant epilepsy (454 left/421 right; 763 temporal/87 frontal/25 posterior quadrant) met inclusion criteria and completed the Boston Naming Test before and after surgery. Clinically meaningful change in naming ability was assessed using reliable change indices for epilepsy. Demographic, cognitive, and seizure variables were examined to determine factors most predictive of naming decline and to develop a decision tree to assist with clinical decision-making. RESULTS: Naming decline was rare in right-sided resections and did not exceed the level expected by chance (5% overall; 90% confidence interval [CI] ± 2%). Naming decline occurred in 41% (CI ± 5%) of patients after left temporal resection (TLR) compared to 10%-12% (CI ± 10%-19%) in other left-sided surgical groups. A sizable proportion of left TLR patients (17%; CI ± 4%) showed substantial declines in naming (>11 points). Decline following left TLR was related to later age at seizure onset, older age at surgery, and higher preoperative naming ability. These factors correctly predicted naming decline in 68% of patients and were associated with degree of decline following left TLR. A decision tree is provided to assist clinicians in identifying patients at low, moderate, or high risk for postoperative naming declines. CONCLUSIONS: In addition to discussions regarding risk for memory decline following left TLR, patients should be counseled about potential decline in word-finding ability.