Biomedical subjects

Michael Westerveld

Publications and source records attributed to Michael Westerveld.

At least 19 recordsLinked to original sources

PubMed2006

The Verbal IQ/Performance IQ discrepancy as a sign of seizure focus laterality in pediatric patients with epilepsy.

A large Verbal IQ (VIQ)/Performance IQ (PIQ) discrepancy has been viewed as a sign of lateralized brain dysfunction. The current study was conducted to determine if the presence of a large VIQ/PIQ discrepancy (15 points) would accurately predict laterality of seizure foci in pediatric patients with epilepsy. A discrepancy score (VIQ-PIQ) was calculated for 130 children (mean age=12.25) undergoing presurgical epilepsy evaluations. Patients were grouped on the basis of language mediation confirmed through the intracarotid amobarbital procedure. Large discrepancies were noted in 34% of the group with typical language and 24% of the children with atypical language organization. When present, this discrepancy accurately lateralized seizure focus for 79% of those with typical and 57% of those with atypical language organization. The presence of the discrepancy was unrelated to seizure control following surgery for the atypical language group. In the typical language group, 85% of children with discrepancies, but only 63% of children without discrepancies, achieved seizure control. Results suggest that the presence of a large discrepancy is not effective, by itself, in lateralizing seizure foci, but may contribute to refining predictions of surgical outcome.

Adolescent↗

PubMed2006

Functional correlates of verbal memory deficits emerging during nicotine withdrawal in abstinent adolescent cannabis users.

BACKGROUND: Cannabis remains the most widely used illicit substance by adolescents and is typically consumed by this population in the context of ongoing tobacco use. Human studies have shown that both cannabis and tobacco exert effects on cognitive function; however, little is known about possible interacting effects of these drugs on brain function and cognition during adolescent development. METHODS: Verbal learning and memory were assessed in 20 adolescent users of tobacco and cannabis and 25 adolescent tobacco users with minimal history of cannabis use. Functional magnetic resonance imaging was used to examine brain function and functional connectivity while a subset of these subjects performed a verbal working memory task. RESULTS: Delayed recall of verbal stimuli deteriorated during nicotine withdrawal among cannabis users but not among comparison subjects. During high verbal working memory load, nicotine withdrawal selectively increased task-related activation of posterior cortical regions and was associated with disruption of frontoparietal connectivity in adolescent cannabis users relative to comparison subjects. CONCLUSIONS: These observations suggest that cannabis use during adolescent development may disrupt neurocircuitry supporting verbal memory formation and that deficits associated with disruption of these neurocircuits are unmasked during nicotine withdrawal.

Adolescent↗

PubMed2005

Visuospatial memory deficits emerging during nicotine withdrawal in adolescents with prenatal exposure to active maternal smoking.

Active maternal smoking during pregnancy elevates the risk of cognitive deficits and tobacco smoking among offspring. Preclinical work has shown that combined prenatal and adolescent exposure to nicotine produces more pronounced hippocampal changes and greater deficits in cholinergic activity upon nicotine withdrawal than does prenatal or adolescent exposure to nicotine alone. Few prior studies have examined the potential modifying effects of gestational exposure to active maternal smoking on cognitive or brain functional response to tobacco smoking or nicotine withdrawal in adolescents. We examined visuospatial and verbal memory in 35 adolescent tobacco smokers with prenatal exposure to active maternal smoking and 26 adolescent tobacco smokers with no prenatal exposure to maternal smoking who were similar in age, educational attainment, general intelligence, and baseline plasma cotinine. Subjects were studied during ad libitum smoking and after 24 h of abstinence from smoking. A subset of subjects from each group also underwent functional magnetic resonance imaging while performing a visuospatial encoding and recognition task. Adolescent tobacco smokers with prenatal exposure experienced greater nicotine withdrawal-related deficits in immediate and delayed visuospatial memory relative to adolescent smokers with no prenatal exposure. Among adolescent smokers with prenatal exposure, nicotine withdrawal was associated with increased activation of left parahippocampal gyrus during early recognition testing of visuospatial stimuli and increased activation of bilateral hippocampus during delayed recognition testing of visuospatial stimuli. These findings extend prior preclinical work and suggest that, in human adolescent tobacco smokers, prenatal exposure to active maternal smoking is associated with alterations in medial temporal lobe function and concomitant deficits in visuospatial memory.

Adolescent↗

PubMed2005

Effects of smoking and smoking abstinence on cognition in adolescent tobacco smokers.

BACKGROUND: In adult animals and humans, nicotine can produce short-term cognitive enhancement and, in some cases, neuroprotection. Recent work in animals, however, suggests that exposure to nicotine during adolescence might be neurotoxic. We tested for evidence of acute and chronic effects of tobacco smoking on cognition in adolescents who smoked tobacco daily and were compared with adolescent nonsmokers. METHODS: Verbal working memory, verbal learning and memory, selective, divided, sustained attention, mood, symptoms of nicotine withdrawal, and tobacco craving were examined in 41 adolescent daily smokers and 32 nonsmokers who were similar in age, gender, and education. Analyses were controlled for general intelligence, reading achievement, parental educational attainment, baseline affective symptoms, and lifetime exposure to alcohol and cannabis. RESULTS: In adolescent smokers, cessation of tobacco use increased tobacco craving, symptoms of nicotine withdrawal, and depressed mood. Adolescent smokers were found to have impairments in accuracy of working memory performance irrespective of recency of smoking. Performance decrements were more severe with earlier age of onset of smoking. Adolescent smokers experienced further disruption of working memory and verbal memory during smoking cessation. As a group, male smokers initiated smoking at an earlier age than female smokers and were significantly more impaired during tests of selective and divided attention than female smokers and nonsmokers. CONCLUSIONS: Adolescent daily tobacco smokers experience acute impairments of verbal memory and working memory after smoking cessation, along with chronic decrements in cognitive performance that are consistent with preclinical evidence that neurotoxic effects of nicotine are more severe when exposure to nicotine occurs at earlier periods in development.

Adolescent↗

PubMed2005

Prediction of verbal memory decline after epilepsy surgery in children: effectiveness of Wada memory asymmetries.

PURPOSE: Differences in Wada memory performance after left and right amobarbital injection are powerful predictors of pre- to postoperative memory change among adult epilepsy patients after anterior temporal lobectomy. It is unknown, however, whether these Wada memory asymmetries apply to children who undergo focal cortical resection or to epilepsy surgery patients who undergo resection outside the temporal lobes. METHODS: To investigate these issues, Wada memory asymmetries and pre- to postoperative neuropsychological memory test performances were examined in 132 children who underwent some form of resective epilepsy surgery. Ninety-three (70%) children showed Wada memory asymmetries in the predicted direction (memory after injection ipsilateral to side of surgery better than memory after contralateral injection), and 39 (30%) did not. RESULTS: Children with Wada memory asymmetries showed significant improvement in verbal memory after surgery as compared with children without Wada memory asymmetries who showed significant verbal memory decline. This result was also obtained when individual cases were examined: 77% of children with Wada memory asymmetries in predicted direction showed no verbal memory decline after surgery, whereas 80% of children without asymmetries had lower postoperative verbal memory (passage recall) test scores. Wada memory asymmetries had no value in predicting postoperative changes in visual-spatial memory. CONCLUSIONS: Wada memory asymmetries may be used as one of the factors to assess risk for verbal memory decline after epilepsy surgery in children.

Adolescent↗

PubMed2005

Normal magnetic resonance imaging and medial temporal lobe epilepsy: the clinical syndrome of paradoxical temporal lobe epilepsy.

OBJECT: The syndrome of medial temporal lobe epilepsy (MTLE) may occur in patients in whom magnetic resonance (MR) images demonstrate normal findings. In these patients, there is no evidence of hippocampal sclerosis on neuroimaging, and histopathological examination of the resected hippocampus does not reveal significant neuron loss. In this paper the authors describe the distinct clinical features of this MTLE subtype, referred to as paradoxical temporal lobe epilepsy (PTLE). METHODS: The authors selected 12 consecutive patients with preoperative findings consistent with MTLE in whom MR imaging did not demonstrate any hippocampal abnormality. Onset of hippocampal seizure was confirmed by long-term intracranial monitoring. There were six female and six male patients with a mean age of 32 +/- 11 years, (mean +/- standard deviation [SD]) at presentation. These patients' seizure histories, available hippocampal volumetric measurements, and hippocampal cell densities in different subfields were reviewed. Sharp electrode recordings from dentate granule cells that had been maintained in hippocampal slices provided a measure of excitation and inhibition in the tissue. We compared these data with those of a cohort of 50 randomly selected patients who underwent anteromedial temporal resection for medial temporal sclerosis (MTS) during the same time period (1987-1999). The durations of follow up (means +/- SDs) for the PTLE and MTS groups were 51 +/- 59 months and 88 +/- 44 months, respectively. A history of febrile seizure was present less frequently in the PTLE group (8%) than in the MTS group (34%). Other risk factors for epilepsy such as trauma, meningoencephalitis, or perinatal injuries were present more frequently in the PTLE group (50%) than in the MTS cohort (36%). In patients in the PTLE group the first seizure occurred later in life (mean age at seizure onset 14 years in the PTLE group compared with 9 years in the MTS group, p = 0.09). Ten patients (83%) in the PTLE cohort and 23 patients (46%) in the MTLE cohort had secondary generalization of their seizures. Among patients with PTLE, volumetric measurements (five patients) and randomized blinded visual inspection (seven patients) of the bilateral hippocampi revealed no atrophy and no increased T2 signal change on preoperative MR images. All patients with PTLE underwent anteromedial temporal resection (amygdalohippocampectomy, in five patients on the left side and in seven on the right side). Electrophysiological studies of hippocampal slices demonstrated that dentate granule cells from patients with PTLE were significantly less excitable than those from patients with MTS. The mean pyramidal cell loss in the CAI subfield in patients in the PTLE group was 20% (range 0-59%) and that in patients in the MTS group was 75% (range 41-90%) (p < 0.001). Maximal neuron loss (mean loss 38%) occurred in the CA4 region in six patients with PTLE (end folium sclerosis). At the last follow-up examination, six patients (50%) in the PTLE group were seizure free compared with 38 patients (76%) in the MTS group. CONCLUSIONS: Clinical PTLE is a distinct syndrome with clinical features and surgical outcomes different from-those of MTS.

Adolescent↗

PubMed2004

Prevention of intraventricular hemorrhage by indomethacin in male preterm infants.

Our multicenter Indomethacin Intraventricular Hemorrhage (IVH) Prevention Trial demonstrated a reduction of IVH in preterm infants. Analysis of our cohort by sex showed indomethacin halved the incidence of IVH, eliminated parenchymal hemorrhage, and was associated with higher verbal scores at 3 to 8 years in boys.

Cardiovascular Agents↗

PubMed2004

Sentence complexity and input modality effects in sentence comprehension: an fMRI study.

Cortical regions engaged by sentence processing were mapped using functional MRI. The influence of input modality (spoken word vs. print input) and parsing difficulty (sentences containing subject-relative vs. object-relative clauses) was assessed. Auditory presentation was associated with pronounced activity at primary auditory cortex and across the superior temporal gyrus bilaterally. Printed sentences by contrast evoked major activity at several posterior sites in the left hemisphere, including the angular gyrus, supramarginal gyrus, and the fusiform gyrus in the occipitotemporal region. In addition, modality-independent regions were isolated, with greatest overlap seen in the inferior frontal gyrus (IFG). With respect to sentence complexity, object-relative sentences evoked heightened responses in comparison to subject-relative sentences at several left hemisphere sites, including IFG, the middle/superior temporal gyrus, and the angular gyrus. These sites showing modulation of activity as a function of sentence type, independent of input mode, arguably form the core of a cortical system essential to sentence parsing.

Acoustic Stimulation↗

PubMed2004

Board certification in clinical neuropsychology: a response to Rohling et al.

Board certification is intended to protect the public by identifying practitioners that have met minimum standards for education and training in their specialty or discipline. For varied reasons, clinical neuropsychology, like professional psychology as a whole, has struggled to achieve levels of board certification comparable to the medical profession. Rohling, Lees-Haley, Langhinrichsen-Rohling, & Williamson (2003) have recently published a critique of the board certification process in clinical neuropsychology as it is conducted by American Board of Clinical Neuropsychology (ABCN), arguing that one reason for this failure is the overly restrictive nature of the process. In their paper, Rohling et al. provide a signal detection analysis that makes several assumptions about the process and conclude with recommendations for improving the process to better identify "competent" neuropsychologists in practice. While we agree in principle with many of their recommendations, and ABCN had, in fact, implemented several prior to publication of their article, the article contains many faulty assumptions and logical inconsistencies that we believe are harmful to constructive review of the certification process. In this article, we provide a critical review of their analysis and present new and additional data that demonstrate the procedure is not overly restrictive. A primary consideration is the low incidence of seeking board certification among professionals who identify themselves as neuropsychologists (i.e., a low application rate), rather than an overly restrictive process. We describe steps taken to improve the process and conclude that there are numerous areas of agreement with Rohling et al., including the need for ongoing review and continued improvement in the board certification process in all psychological specialties.

Certification↗

PubMed2004

Impact of cannabis use on brain function in adolescents.

Cannabis is the most common illicit substance used by adolescents. This paper reports results of a pilot study using fMRI and a working memory task to compare brain function of adolescent cannabis users to that of two control groups, one matched for tobacco use and the other for nonsmokers.

Adolescent↗

PubMed2004

Intracarotid Amytal memory test and hippocampal magnetic resonance imaging volumetry: validity of the Wada test as an indicator of hippocampal integrity among candidates for epilepsy surgery.

OBJECT: Intracarotid Amytal testing (the Wada test) has been used to lateralize language and identify patients who may be at risk for memory impairment after temporal lobectomy. The goal of this study was to determine the validity of the Wada test in the assessment of pathological conditions of the hippocampus among candidates for epilepsy surgery. The authors examined the correlation between the functional integrity of the hippocampus, measured using the Wada test, and quantitative measures of hippocampal pathology, determined by obtaining volumetric measurements of the hippocampus with the aid of magnetic resonance (MR) imaging. METHODS: The authors reviewed the relationship between memory scores on the Wada test and hippocampal volumes measured on preoperative MR images in 76 patients who underwent anteromedial temporal lobectomy and amygdalohippocampectomy for the treatment of medically refractory temporal lobe epilepsy. The data were analyzed with respect to their usefulness in lateralizing the seizure focus and predicting the long-term postoperative memory outcome. Right and left hippocampal volume measurements did not correlate with one another (p > 0.1). Similarly, following a left carotid artery injection of Amytal the patients' right hemisphere memory was not significantly related to their left hemisphere memory on the Wada test (p'> 0.1). On the other hand, the patients' right hemisphere memory significantly correlated with their right hippocampal volume (r = 0.51; p < 0.001) and their left hemisphere memory significantly correlated with their left hippocampal volume (r = 0.51; p < 0.001). Both right and left hemisphere memory scores correlated with the hippocampal volumetry ratio (r = 0.47 and r = 0.45, respectively; both p < 0.001). Lateralization of a seizure focus based on hippocampal volumetry results was significantly related to lateralization based on the results of the Wada test (r = 0.49; p < 0.01). The disparity between the Wada memory scores on ipsilateral and contralateral sides was significantly and inversely related to the change in verbal memory following temporal lobectomy (r = -0.28; p < 0.02). The preoperative hippocampal volumetry ratio also significantly and inversely correlated with the change in verbal memory after surgery (r = -0.31; p < 0.01). CONCLUSIONS: The Wada memory test may be a valuable method of measuring the functional integrity of the hippocampus. The systematic study of MR imaging-acquired morphological data and Wada-acquired neuropsychological data may increase our understanding of the location of material-specific memory and the selection of eligible candidates for epilepsy surgery.

Adolescent↗

PubMed2003

Change in cognitive function over time in very low-birth-weight infants.

CONTEXT: Preterm very low-birth-weight (VLBW) infants have a high prevalence of neurodevelopmental disability when evaluated during the first several years of life. However, recent experimental data suggest that the developing brain may recover from or compensate for injury. OBJECTIVE: To determine if there is cognitive improvement throughout early and middle childhood following VLBW birth. DESIGN, SETTING, AND PARTICIPANTS: Follow-up data of 296 infants born weighing 600 to 1250 g who participated in a prospective, randomized, placebo-controlled intraventricular hemorrhage (IVH) prevention study performed at 3 northeastern US hospitals between September 1989 and August 1992 and who were serially evaluated at 36, 54, 72, and 96 months of corrected age (CA). MAIN OUTCOME MEASURES: The age-normed Peabody Picture Vocabulary Test-Revised (PPVT-R) score and measures of intelligence. RESULTS: Overall, the median PPVT-R score increased from 88 at 36 months of CA to 99 at 96 months of CA; when data from 36 and 96 months of CA were compared, 45% of children gained 10 points or more and 12.5% showed a 5- to 9-point increase in test scores. Similar findings were noted for full-scale and verbal IQ scores. Multivariate analyses demonstrated that increasing age, residence in a 2-parent household, and higher levels of maternal education were all significantly associated with higher PPVT-R scores (for each, P<.001). In addition, early intervention led to greater increases over time in PPVT-R scores among children whose mothers had less than a high school education compared with those with a high school education level or greater (P =.03 by test for interaction). Although most children showed improvement in PPVT-R scores with increasing CA, children with early-onset IVH and subsequent significant central nervous system injury had the lowest PPVT-R scores initially and the scores declined over time (P =.009 by test for interaction). CONCLUSIONS: The majority of VLBW children had improvement in verbal and IQ test scores over time. Only children with early-onset IVH followed by significant central nervous system injury had low PPVT-R scores that declined over time.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2003

Selective frontal, parietal, and temporal networks in generalized seizures.

Are "generalized" seizures truly generalized? Generalized tonic-clonic seizures are classified as either secondarily generalized with local onset or primarily generalized, without known focal onset. In both types of generalized seizures widespread regions of the nervous system engage in abnormally synchronous and high-frequency neuronal firing. However, emerging evidence suggests that all neurons are not homogeneously involved; specific nodes within the network may be crucial for the propagation and behavioral manifestations of generalized tonic-clonic seizures. Study of human tonic-clonic seizures has been limited by problems with patient movement and variable seizure types. To circumvent these problems, we imaged generalized tonic-clonic seizures during electroconvulsive therapy, in which seizure type and timing are well controlled. (99m)Tc-hexamethylpropylene amine oxime injections during seizures provide a "snapshot" of cerebral blood flow that can be imaged by single photon emission computed tomography (SPECT) after seizure termination. Here we show that focal regions of frontal and parietal association cortex show the greatest relative signal increases. Involvement of the higher-order association cortex may explain the profound impairment of consciousness seen in generalized seizures. In addition, focal involvement of the dominant temporal lobe was associated with impaired retrograde verbal memory. Similar focal increases were also seen in imaging of spontaneous secondarily generalized tonic-clonic seizures. Relative sparing of many brain regions during both spontaneous and induced seizures suggests that specific networks may be more important than others in so-called generalized seizures.

Adult↗

PubMed2003

Long-term outcome of vagus nerve stimulation for refractory partial epilepsy.

We assessed 1- and 2-year outcomes of specific seizure types, quality of life, depression, and anxiety among patients treated with vagus nerve stimulation (VNS) for refractory partial epilepsy. Patients completed a seizure questionnaire, the Quality of Life in Epilepsy-89 (QOLIE-89) questionnaire, the Beck Anxiety Inventory (BAI), and the Beck Depression Inventory (BDI) at baseline and 1 year, and 2 years after activation of VNS. VNS was associated with >or=50% reduction in total seizure frequency in 54% of patients at 1 year and 61% of patients 2 years post-VNS activation compared with baseline. No statistically significant changes from baseline to 12 or 24 months were found in mean quality of life, depression, or anxiety measures in the overall study population. Patients with at least 50% reduction in seizures had significant improvement in anxiety at 12 and 24 months compared with patients who did not have the same degree of seizure reduction.

Adolescent↗

PubMed2003

Wada memory performance predicts seizure outcome after epilepsy surgery in children.

PURPOSE: Wada memory asymmetries were examined in children from four comprehensive epilepsy surgery centers who subsequently underwent epilepsy surgery to determine whether Wada memory performance could predict degree of seizure relief in children. METHODS: One hundred fifty-six children (between ages 5 and 16 years) with intractable epilepsy underwent Wada testing before resective epilepsy surgery (93 within the left hemisphere, and 63 within the right hemisphere). Memory stimuli were presented soon after intracarotid amobarbital injection, and recognition memory for the items was assessed after return to neurologic baseline. Eighty-eight children underwent unilateral temporal lobe resection, and 68 had extratemporal lobe resections. One hundred four (67%) children were seizure free (Engel class I), and 52 (33%) were not seizure free (Engel classes II-IV) at follow-up (mean follow-up interval, 2.3 years). RESULTS: Seizure-free children recalled 19.3% more Wada memory items after ipsilateral injection than did non-seizure-free children (p = 0.008). If analysis was restricted to youngsters with temporal lobectomies (TLs), seizure-free children recalled 27.7% more items after ipsilateral injection than did non-seizure-free TL children (p = 0.004). With regard to individual patient prediction, 75% of children who had memory score asymmetries consistent with the seizure focus were seizure free. In contrast, only 56% of children whose memory score asymmetries were inconsistent with the seizure focus were seizure free (p = 0.01). CONCLUSIONS: Results suggest that Wada memory performance asymmetries are related to the degree of seizure relief after epilepsy surgery in children and adolescents.

Adolescent↗

PubMed2003

Levetiracetam efficacy in refractory partial-onset seizures, especially after failed epilepsy surgery.

PURPOSE: We conducted a retrospective study to evaluate the efficacy of levetiracetam as adjunctive therapy in patients with localization-related epilepsy, and specifically in the subset of patients for whom epilepsy surgery failed. METHODS: Eighty-two patients with uncontrolled partial-onset seizures treated with levetiracetam were identified; epilepsy surgery had failed for 21 (25.6%; group I), and 61 (74.4%) had no prior surgery (group II). Group I and group II patients were comparable in age (mean, 40.7 vs. 41.5 years) and age at seizure onset (mean, 14.4 vs. 18.2 years). Patients who had >/=50% reduction in seizure frequency were considered responders; the remaining patients were considered nonresponders. RESULTS: In patients (group I) for whom surgery had failed, responder rate was 76.1% (16 of 21), including 10 (47.6%) patients who became seizure free. In nonsurgical patients (group II), responder rate was 34.3% (21 of 61), including nine (14.7%) patients who became seizure free. In group I, 11 (91.6%) of 12 temporal resection patients were responders, of whom eight were seizure free; of the remaining nine operated (extratemporal) patients, five (55.5%) were responders, and two were seizure free. In three responders, all in group I, a severe, delayed psychotic syndrome developed 4 to 9 months after levetiracetam introduction, leading to its discontinuation. CONCLUSIONS: These findings suggest that adjunctive levetiracetam therapy should be considered early after failed epilepsy surgery, especially after temporal resection, and may have implications for its use before surgical intervention. Patients should be under close psychiatric observation in this clinical setting.

Adolescent↗

PubMed2003

School-age outcomes of very low birth weight infants in the indomethacin intraventricular hemorrhage prevention trial.

OBJECTIVE: The cohort consisted of 328 very low birth weight infants (600-1250 g birth weight) who were enrolled in the low-dose prophylactic indomethacin prevention trial and were intraventricular hemorrhage (IVH) negative at 6 postnatal hours. The objective was to determine the effects of both IVH and indomethacin on cognitive, language, and achievement performance at 8 years of age. METHODS: The cohort was divided into 4 subgroups for analysis: indomethacin plus IVH, indomethacin no IVH, saline plus IVH, and saline with no IVH. The children were evaluated prospectively at 8 years of age with a neurologic assessment, history of school performance, and a battery of cognitive, academic, behavioral, and functional assessments. RESULTS: Children in both IVH groups had more cerebral palsy; more hearing impairment; lower daily living skills scores; lower IQ, vocabulary, and reading and mathematics achievement test scores; and greater educational resource needs. With logistic regression analyses grade 3 to 4 IVH, periventricular leukomalacia and/or ventriculomegaly, male gender, maternal education, and language spoken in the home contributed to outcomes. No effects of indomethacin or gestational age were identified. CONCLUSIONS: Although biological factors including IVH, ventriculomegaly, and periventricular leukomalacia contribute significantly to school age outcomes among very low birth weight survivors at 8 years of age, social and environmental factors including maternal level of education and primary language spoken in the home are also important contributors to outcome.

Cerebral Hemorrhage↗

PubMed2002

Effect of Wada methodology in predicting lateralized memory impairment in pediatric epilepsy surgery candidates.

Because Wada evaluations are not standardized, it is impossible to know to what degree method variance accounts for reported differences in results. To examine this problem, three comprehensive epilepsy surgery centers compared the efficacy of two Wada memory methods to predict seizure onset laterality in 152 children being considered for epilepsy surgery. Wada memory asymmetries were evaluated using either real objects with no verbal response required or more mixed stimuli requiring a verbal response. When using real objects, Wada memory performance was significantly worse when relying on the side of seizure onset in both left and right seizure onset children. In contrast, Wada memory performance using mixed stimuli was worse on the side of seizure onset only among patients with seizures originating in the left-hemisphere. The superiority of real objects was most apparent in younger children with left side seizure onset. Results suggest the use of mixed stimuli is less sensitive to the effects of unilateral seizure onset, and thus, diminishes the capacity of the Wada test to predict lateralized seizure onset in children.

Journal Article↗