The Symbol Digit Modalities Test: a screening instrument for brain-damaged children

Abnormal eye movements increase as motor disabilities and cognitive impairments become more evident in Multiple Sclerosis: A novel eye-tracking study

Background

Eye movements can reflect brain alterations and inform on the presence of motor disabilities and cognitive impairments in people with multiple sclerosis (pwMS).

Objective

The aim of the study was to determine the correlation between motor and cognitive measurements and eye movement parameters when performing the n-back task (NBKT).

Methods

This was a cross-sectional study carried out at Ramos Mejía Hospital, a center specialized in demyelinating diseases in Buenos Aires, Argentina. The study population consisted of 66 patients with relapsing-remitting multiple sclerosis (RRMS) and 5 patients with secondary progressive multiple sclerosis (SPMS). pwMS performed the n-back test while using a device head mounted display (HMD) with eyetracking capabilities in order to capture eye movement. Clinical motor and cognitive measures were assessed with Expanded Disability Status Scale (EDSS), Nine Hole Peg Test (NHPT), Timed 25-Foot Walk (T25FW), and Symbol Digit Modalities Test (SDMT).

Results

pwMS showed strong and statistically significant correlations between gaze duration; number of fixations, saccade amplitude and motor disabilities and cognitive impairments as measured by EDSS, NHPT, T25FW, and SDMT.

Conclusion

This study found significant correlations between eye movement behavior and motor and cognitive disability in pwMS. These findings suggest that eye movements have the potential to be used as a surrogate biomarker in MS progression.

Thalamocortical Functional Connectivity in Patients With White Matter Hyperintensities

Background: White matter hyperintensities (WMH)s is a very common neuroradiological manifestation in the elderly and is an increased risk of dementia and cognitive decline. As we all know, the thalamocortical circuit plays an important part in cognition regulation. However, the role of this circuit in WMHs and its related cognitive deficits is still unclear. Method: Eighty WMH patients and 37 healthy controls (HCs) were enrolled in the current study. WMH patients were divided into a mild WMH group (n = 33) and moderate-severe WMH group (n = 47) according to Fazekas scores. Resting-state functional magnetic resonance imaging (rs-fMRI) data of all participants were collected for thalamocortical functional connectivity (FC) analysis. The analysis was performed in two steps. First, the whole cerebral cortex was divided into six regions of interest (ROIs), which were used as seeds to investigate the changes of FC with the thalamus. Then, the subregion of the thalamus generated in the previous step was used as the seed for FC analysis with the whole brain. Results: In the first step of FC analysis, it was found that precentral gyrus (PrCG)-interthalamic adhesion (ITA) FC values in moderate-severe WMH group were higher than those in HC and mild WMH groups. However, when compared with the HC group, the increase of PrCG-ITA FC values in mild WMH group was not statistically significant. In the second step of FC analysis, the ITA was set as the seed, and compared with the HC group, the results showed that the FC values of the ITA-medial frontal gyrus (MFG) in mild group and moderate-severe WMH groups were significantly increased. In addition, the FC values in moderate-severe group were significantly higher than those in mild group. Finally, it was also found that FC values (PrCG-ITA and ITA-MFG) were significantly correlated with neuropsychological test results for multiple cognitive functions such as memory, execution and attention in WMH patients. Conclusion: Abnormal thalamocortical FC was closely related with cognitive impairments in WMH patients.

Emotional Awareness and Cognitive Performance in Borderline Intellectual Functioning Young Adolescents

According to DSM-5 and ICD-10, borderline intellectual functioning (BIF) should not be classified properly as a disorder. However, BIF people may present relevant problems of adaptive functioning in several areas of daily activities, and they seem to be more vulnerable to mental diseases. Young adolescence may be considered a particular period for emotional information processing. The "own and others' emotions" awareness can play a crucial role in many daily life situations, such as decision making, interpersonal relationships, and decoding of facial expressions. On this background, a BIF young adolescents group underwent a neuropsychological assessment including emotional and cognitive domains, and was compared with a healthy young adolescents control group (HC). In the overall sample, a significant negative correlation between general intellectual abilities and emotional awareness was found. The BIF group showed a significantly greater level of alexithymia and a poorer performance in higher cognitive tasks than HC group. As hypothesized, a border cognitive functioning influences mentalization processes as ability to discriminate and monitor emotions, as well as higher domains of cognition.

Quantitative Assessment of Pathological Tau Burden in Essential Tremor: A Postmortem Study

Essential tremor (ET) patients develop more cognitive impairment and dementia than controls, although there are surprisingly few data on the neuropathological basis for cognitive changes in ET. In this postmortem study, we assessed tau and other pathologies in 26 ET cases and 73 controls (non-ET) (1:3 matching). The mean age = 88.6 years; 55% were cognitively normal, 24% had mild cognitive impairment (MCI), and 20% had dementia. We found similar burdens of pathology using Braak, β-amyloid and Lewy body assessments in ET and controls. In contrast, among cognitively normal subjects, ET cases had a higher number of NFT-positive neurons in the neocortex than controls (p < 0.001); the number of NFT-positive neurons in the medial temporal lobe was similar in these 2 groups (p = 0.22). Among subjects with MCI, ET cases also had higher numbers of NFT-positive neurons in the neocortex than controls (p < 0.001) but again, not in the medial temporal lobe (p = 0.55). Among subjects with dementia, the number of NFT-positive neurons was similar in ET cases and controls. Cognitive function correlated with quantitative neurofibrillary tangle counts in ET cases and controls. In the context of ET, pre-dementia tau burden is higher than in the absence of ET, suggesting a predisposition to tau pathology.

Perception of Emotional Facial Expressions in Amyotrophic Lateral Sclerosis (ALS) at Behavioural and Brain Metabolic Level

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) primarily impairs motor abilities but also affects cognition and emotional processing. We hypothesise that subjective ratings of emotional stimuli depicting social interactions and facial expressions is changed in ALS. It was found that recognition of negative emotions and ability to mentalize other's intentions is reduced.

METHODS

Processing of emotions in faces was investigated. A behavioural test of Ekman faces expressing six basic emotions was presented to 30 ALS patients and 29 age-, gender and education matched healthy controls. Additionally, a subgroup of 15 ALS patients that were able to lie supine in the scanner and 14 matched healthy controls viewed the Ekman faces during functional magnetic resonance imaging (fMRI). Affective state and a number of daily social contacts were measured.

RESULTS

ALS patients recognized disgust and fear less accurately than healthy controls. In fMRI, reduced brain activity was seen in areas involved in processing of negative emotions replicating our previous results. During processing of sad faces, increased brain activity was seen in areas associated with social emotions in right inferior frontal gyrus and reduced activity in hippocampus bilaterally. No differences in brain activity were seen for any of the other emotional expressions. Inferior frontal gyrus activity for sad faces was associated with increased amount of social contacts of ALS patients.

CONCLUSION

ALS patients showed decreased brain and behavioural responses in processing of disgust and fear and an altered brain response pattern for sadness. The negative consequences of neurodegenerative processes in the course of ALS might be counteracted by positive emotional activity and positive social interactions.

Symbol Digit Modalities Test: Normative data for the Latin American Spanish speaking adult population

OBJECTIVE

To generate normative data on the Symbol Digit Modalities Test (SDMT) across 11 countries in Latin America, with country-specific adjustments for gender, age, and education, where appropriate.

METHOD

The sample consisted of 3,977 healthy adults who were recruited from Argentina, Bolivia, Chile, Cuba, El Salvador, Guatemala, Honduras, Mexico, Paraguay, Peru, and, Puerto Rico. Each subject was administered the SDMT as part of a larger neuropsychological battery. A standardized five-step statistical procedure was used to generate the norms.

RESULTS

The final multiple linear regression models explained 29-56% of the variance in SDMT scores. Although there were gender differences on the SDMT in Mexico, Honduras, Paraguay, and Guatemala, none of the four countries had an effect size greater than 0.3. As a result, gender-adjusted norms were not generated.

CONCLUSIONS

This is the first normative multicenter study conducted in Latin America to create norms for the SDMT; this study will have an impact on the future practice of neuropsychology throughout the global region.

Ocular motor signatures of cognitive dysfunction in multiple sclerosis

The anatomical and functional overlap between ocular motor command circuitry and the higher-order networks that form the scaffolding for cognition makes for a compelling hypothesis that measures of ocular motility could provide a means to sensitively interrogate cognitive dysfunction in people with multiple sclerosis (MS). Such an approach may ultimately provide objective and reproducible measures of cognitive dysfunction that offer an innovative capability to refine diagnosis, improve prognostication, and more accurately codify disease burden. A further dividend may be the validation and application of biomarkers that can be used in studies aimed at identifying and monitoring preventative, protective and even restorative properties of novel neurotherapeutics in MS. This Review discusses the utility of ocular motor measures in patients with MS to characterize disruption to wide-ranging networks that support cognitive function.

Validation of the Neuro-QoL measurement system in children with epilepsy

OBJECTIVE

Children with epilepsy often face complex psychosocial consequences that are not fully captured by existing patient-reported outcome (PRO) measures. The Neurology Quality of Life Measurement System "Neuro-QoL" was developed to provide a set of common PRO measures that address issues important to people with neurologic disorders. This paper reports Neuro-QoL (anxiety, depression, interaction with peers, fatigue, pain, cognitive function, stigma, and upper and lower extremity functions) validation in children with epilepsy.

METHOD

Patients (aged 10-18years) diagnosed with epilepsy completed Neuro-QoL and legacy measures at time 1 (initial study visit) and 6-month follow-up. Internal consistency reliability was also evaluated. Concurrent validity was assessed by comparing Neuro-QoL measures with more established "legacy" measures of the same concepts. Clinical validity was evaluated by comparing mean Neuro-QoL scores of patients grouped by clinical anchors such as disease severity. Responsiveness of the Neuro-QoL from time 1 (initial study visit) to 6months was evaluated using self-reported change as the primary anchor.

RESULTS

Sixty-one patients (mean age=13.4years; 62.3% male, 75.9% white) participated. Most patients (64.2%) had been seizure-free in the 3months prior to participation, and seizure frequency was otherwise described as follows: 17.8% daily, 13.3% weekly, 35.6% monthly, and 33.3% yearly. All patients were taking antiepileptic drugs. Patients reported better function/less symptoms compared to the reference groups. Internal consistency (alpha) coefficients ranged from 0.76 to 0.87. Patients with different seizure frequencies differed on anxiety (p<.01) and cognitive function (p<.05). Compared to patients on polytherapy, those on monotherapy had better upper extremity scores (p<.05). Compared to those with localized seizures, those experiencing generalized seizures reported worse stigma (p<.05). Depression, anxiety, lower extremity, fatigue, pain, interaction with peers, and stigma also significantly discriminated patients with different levels of quality of life (p≤.05). All Neuro-QoL measures were significantly correlated with other measures assessing similar domains. Stigma was related to self-reported change in several areas of functioning but in sometimes unexpected directions.

SIGNIFICANCE

The Neurology Quality of Life Measurement System is a valid and reliable assessment tool for children with epilepsy and can be used in research and clinical settings.

Movement strategies for maintaining standing balance during arm tracking in people with multiple sclerosis

The purpose of this study was to quantify hip and ankle movement strategies during a standing arm tracking task in people with multiple sclerosis (MS). Full-body kinematics and kinetics were assessed with motion analysis cameras and force plates in nine MS and nine age-matched control subjects. While standing, participants used their dominant hand to track a target moving around a large horizontal or vertical figure eight on a screen in front of them. The target moved at constant speed, or linearly increasing speeds, with a frequency between 0.05 Hz and 0.35 Hz. Hip and ankle moments and angles during tracking were calculated from kinematic and kinetic measurements. Ratios of peak-to-peak (PP) hip/ankle moments (kinetics) and angles (kinematics) were calculated to determine the strategies of the hips and ankles used to maintain balance during arm movements. Center of mass (CoM) root mean square (RMS) acceleration was calculated as a measure of overall balance performance. The MS group produced larger PP hip/ankle moments at all speeds compared with the control group (P < 0.05). The CoM RMS acceleration increased with tracking speed for both groups but was not significantly different between groups. Additionally, the ratios of hip to ankle moments were highly correlated with the Berg Balance Scale during horizontal steady-speed tracking in MS. These results suggest that people with MS increase the use of the hip during standing arm tracking compared with age-matched control subjects. This adapted strategy might allow people with MS to achieve balance performance similar to control subjects, possibly increasing the importance of the hip in maintaining balance during voluntary movements.

Additional resources and the default mode network: Evidence of increased connectivity and decreased white matter integrity in amyotrophic lateral sclerosis

In amyotrophic lateral sclerosis (ALS), cognition is affected. Cortical atrophy in frontal and temporal areas has been associated with the cognitive profile of patients. Additionally, reduced metabolic turnover and regional cerebral blood flow in frontal areas indicative of reduced neural activity have been reported for ALS. We hypothesize that functional connectivity in non-task associated functional default mode network (DMN) is associated with cognitive profile and white matter integrity. This study focused on specific cognitive tasks known to be impaired in ALS such as verbal fluency and attention, and the relationship with functional connectivity in the DMN and white matter integrity. Nine patients and 11 controls were measured with an extensive neuropsychological battery. Resting-state functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) data were acquired. Results showed that ALS patients performed significantly worse in attention and verbal fluency task. Patients showed increased functional connectivity in parahippocampal and parietal areas of the non-task associated DMN compared to controls. The more pronounced the cognitive deficits, the stronger the increase in functional connectivity in those areas. White matter integrity was reduced in frontal areas in the patients. In conclusion, increased connectivity in the DMN in parahippocampal and parietal areas might represent recruitment of accessory brain regions to compensate for dysfunctional frontal networks.

Association analysis of the catechol-O-methyltransferase /methylenetetrahydrofolate reductase genes and cognition in late-onset depression

AIMS

Increasing evidence suggests that the catechol-O-methyltransferase (COMT) gene might be associated with cognition in patients with mental disorders and healthy people. The metabolic pathways of COMT and methylenetetrahydrofolate reductase (MTHFR) are closely interconnected. In this study, we aimed to examine whether the COMT-MTHFR genotype interacted with cognitive function in late-onset depression (LOD) patients and COMT Val/Val homozygous individuals who also carried the MTHFR T allele and had poor neuropsychological test performance.

METHODS

Ninety-seven unrelated LOD patients who met DSM-IV criteria for major depressive disorder were recruited for the study and 103 normal controls were recruited from the local community. All of these patients and 44 normal controls completed a series of neuropsychological tests. Patients and normal controls were genotyped for COMT (rs4680) and MTHFR (rs1801133) variants using polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

There were no significant differences in the frequencies of the single alleles and genotypes of two polymorphisms between LOD patients and normal controls. No main effects of COMT or MTHFR genotype on any neuropsychological test performance were observed. There was a significant interactive effect of COMT Val158Met and MTHFR C677T polymorphisms on the Symbol Digit Modalities Test independent of diagnosis (P < 0.05). After controlling for covariates, the subjects with COMT Met/ Met and MTHFR C/C genotype had better Symbol Digit Modalities Test performance.

CONCLUSIONS

The results suggest no major effect of COMT or MTHFR on cognitive function alone. However, an interaction of COMT Val158Met and MTHFR C677T polymorphisms may be associated with cognitive function. Further studies in a large sample are needed to replicate the genetic role in the LOD patients.

Validity of the Neurology Quality-of-Life (Neuro-QoL) measurement system in adult epilepsy

Epilepsy is a chronic neurological disorder that results in recurring seizures and can have a significant adverse effect on health-related quality of life (HRQL). The Neuro-QoL measurement initiative is an NINDS-funded system of patient-reported outcome measures for neurology clinical research, which was designed to provide a precise and standardized way to measure HRQL in epilepsy and other neurological disorders. Using mixed-method and item response theory-based approaches, we developed generic item banks and targeted scales for adults and children with major neurological disorders. This paper provides empirical results from a clinical validation study with a sample of adults diagnosed with epilepsy. One hundred twenty-one people diagnosed with epilepsy participated, the majority of which were male (62%) and Caucasian (95%), with a mean age of 47.3 (SD=16.9). Baseline assessments included Neuro-QoL short forms and general and external validity measures. The Neuro-QoL short forms that are not typically found in other epilepsy-specific HRQL instruments include Stigma, Sleep Disturbance, Emotional and Behavioral Dyscontrol, and Positive Affect and Well-Being. Neurology Quality-of-Life short forms demonstrated adequate reliability (internal consistency range=.86-.96; test-retest range=.57-.89). Pearson correlations (p<.01) between Neuro-QoL forms of emotional distress (anxiety, depression, stigma) and the QOLIE-31 Emotional Well-Being subscale were in the moderate-to-strong range (r's=.66, .71 and .53, respectively), as were relations with the PROMIS Global Mental Health subscale (r's=.59, .74 and .52, respectively). Moderate correlations were observed between Neuro-QoL Social Role Performance and Satisfaction and the QOLIE-31 Social Function (r's=.58 and .52, respectively). In measuring aspects of physical function, the Neuro-QoL Mobility and Upper Extremity forms demonstrated moderate associations with the PROMIS Global Physical Function subscale (r's=.60 and .61, respectively). Neuro-QoL measures of perceived cognitive function (executive function and general concerns) produced moderate-to-strong correlations with the QOLIE-31 Cognition subscale (r's=.65 and .75, respectively) and moderate relations with the Liverpool Adverse Events Profile (r's=.51 and .69, respectively). Finally, the Neuro-QoL Fatigue measure demonstrated moderate associations with the QOLIE-31 Energy/Fatigue subscale (r=-.65), Liverpool Adverse Events Profile (r=.69), and the Liverpool Seizure Severity Scale (r=.50). Five Neuro-QoL short forms demonstrated statistically significant responsiveness to change at 5-7months, including Fatigue, Sleep Disturbance, Depression, Positive Affect and Well-Being, and Emotional and Behavioral Dyscontrol. Overall, Neuro-QoL instruments showed good evidence for internal consistency, test-retest reliability, convergent validity, and responsiveness to change over several months. These results support the validity of Neuro-QoL to measure HRQL in adults with epilepsy.

Hippocampal volume is related to cognitive decline and fornicial diffusion measures in multiple sclerosis

PURPOSE

To assess for associations between hippocampal atrophy and measures of cognitive function, hippocampal magnetization transfer ratio (MTR), and diffusion measures of the fornix, the largest efferent white matter tract from the hippocampus, in patients with multiple sclerosis (MS) and controls.

MATERIALS AND METHODS

A total of 53 patients with MS and 20 age- and sex-matched healthy controls participated in cognitive testing and scanning including high spatial-resolution diffusion imaging and a T1-MPRAGE scan. Hippocampal volume and fornicial thickness measures were calculated and compared to mean values of fornicial transverse diffusivity, mean diffusivity, longitudinal diffusivity, fractional anisotropy, mean hippocampal MTR, and scores on measures of episodic memory, processing speed, and working memory tasks.

RESULTS

In patients with MS, hippocampal volume was significantly related to fornicial diffusion measures (P<7×10(-4)) and to measures of verbal (P=0.030) and visual spatial (P=0.004) episodic memory and a measure of information processing speed (P<0.037).

DISCUSSION

These results highlight the role of the hippocampus in cognitive dysfunction in patients with MS and suggest that measures of hippocampal atrophy could be used to capture aspects of disease progression.

Relative changes in ankle and hip control during bilateral joint movements in persons with multiple sclerosis

OBJECTIVE

The purpose of this study was to quantify hip and ankle impairments contributing to movement dysfunction in multiple sclerosis (MS).

METHODS

Volitional phasing of bilateral hip and ankle torques was assessed using a load-cell-instrumented servomotor drive system in ten participants with MS and 10 age-matched healthy participants. The hips and ankles were separately bilaterally oscillated 180° out of phase (40° range of motion) at a frequency of 0.75 Hz while the other joints were held stationary. Participants were instructed to assist in the same direction as the robot-imposed movement. The hip and ankle torques were measured and work was calculated for each movement.

RESULTS

Total negative work at the ankle was significantly different between groups (p=0.040). The participants with MS produced larger negative work during hip flexion (p=0.042) and ankle flexion (p=0.037). Negative work at the hip was significantly correlated with the Berg Balance Scores and Timed 25 Feet Walk Test, and trends demonstrated increasing negative work with increasing clinical impairment in MS.

CONCLUSIONS

These results suggest an increased importance of the hip in functional balance and gait in MS.

SIGNIFICANCE

Rehabilitation strategies targeting ankle recovery or compensation using the hip might improve movement function in MS.

Development and validation of the positive affect and well-being scale for the neurology quality of life (Neuro-QOL) measurement system

PURPOSE

To develop and validate an item-response theory-based patient-reported outcomes assessment tool of positive affect and well-being (PAW). This is part of a larger NINDS-funded study to develop a health-related quality of life measurement system across major neurological disorders, called Neuro-QOL.

METHODS

Informed by a literature review and qualitative input from clinicians and patients, item pools were created to assess PAW concepts. Items were administered to a general population sample (N = 513) and a group of individuals with a variety of neurologic conditions (N = 581) for calibration and validation purposes, respectively.

RESULTS

A 23-item calibrated bank and a 9-item short form of PAW was developed, reflecting components of positive affect, life satisfaction, or an overall sense of purpose and meaning. The Neuro-QOL PAW measure demonstrated sufficient unidimensionality and displayed good internal consistency, test-retest reliability, model fit, convergent and discriminant validity, and responsiveness.

CONCLUSION

The Neuro-QOL PAW measure was designed to aid clinicians and researchers to better evaluate and understand the potential role of positive health processes for individuals with chronic neurological conditions. Further psychometric testing within and between neurological conditions, as well as testing in non-neurologic chronic diseases, will help evaluate the generalizability of this new tool.

High spatial and angular resolution diffusion-weighted imaging reveals forniceal damage related to memory impairment

INTRODUCTION

Diffusion tensor imaging (DTI) measures in patients with multiple sclerosis (MS), particularly those measures associated with a specific white matter pathway, have consistently shown correlations with function. This study sought to investigate correlations between DTI measures in the fornix and common cognitive deficits in MS patients, including episodic memory, working memory and attention.

MATERIALS AND METHODS

Patients with MS and group age- and sex-matched controls underwent high-resolution diffusion scanning (1-mm isotropic voxels) and cognitive testing. Manually drawn forniceal regions of interest were applied to individual maps of tensor-derived measures, and mean values of transverse diffusivity (TD), mean diffusivity (MD), longitudinal diffusivity (LD) and fractional anisotropy (FA) were calculated.

RESULTS

In 40 patients with MS [mean age ± S.D.=42.55 ± 9.1 years; Expanded Disability Status Scale (EDSS)=2.0 ± 1.2; Multiple Sclerosis Functional Composite (MSFC) score=0.38 ± 0.46] and 20 healthy controls (mean age ± S.D.=41.35 ± 9.7 years; EDSS=0.0 ± 0; MSFC score=0.74 ± 0.24), we found that FA, MD and TD values in the fornix were significantly different between groups (P<.03), and patient performance on the Brief Visuospatial Memory Test-Revised (BVMT-R) was correlated with DTI measures (P<.03).

DISCUSSION

These results are consistent with findings of axonal degeneration in MS and support the use of DTI as an indicator of disease progression.

Normative data for the digit-letter substitution task in school children

BACKGROUND/AIMS

To establish the norms for the substitution task, a measure of psychomotor performance.

MATERIALS AND METHODS

Eight hundred and forty three school students were selected in the present study aged between 9-16 years (mean age = 12.14; SD = 1.77). Subjects were assessed one at a time for Digit-Letter Substitution Task (DLST).

RESULTS

Both age and sex influenced performance on the DLST; therefore, correction scores were obtained on the basis of these factors.

CONCLUSIONS

The availability of the Indian normative data for the DLST will allow wider application of this test in clinical practice.

Brain responses to emotional stimuli in patients with amyotrophic lateral sclerosis (ALS)

Amyotrophic lateral sclerosis (ALS), a progressive motor neuron disease, affects movement and communication abilities and emotional processing. Subjective ratings of emotional stimuli depicting social interactions and facial expressions differed significantly between ALS patients and healthy controls in a previous study with a reduction of negative emotional valence (pleasantness) and lower subjective arousal (excitement) in ALS patients. In the present study, sixty similar emotional slides were presented to 13 ALS patients, 15 matched healthy controls and six tetraplegic patients. Subjective reports of valence and arousal as well as brain responses to the affective pictures using functional magnetic resonance imaging (fMRI) were measured. The picture series was presented twice with a 6-months interval to investigate effects of disease progression. ALS patients presented an increased brain response in the right supramarginal area and a reduced brain response in extrastriate visual areas at both measurements compared with healthy controls. Within the ALS patients' group a reduction of brain responses in the anterior insula at the follow-up was correlated with the subjective arousal. The reduced response in the anterior insula is tentatively interpreted as indicating reduced arousal during the course of the disease at the neural and behavioural level. The reduction of activity in extrastriate visual areas might be similarly interpreted. The increased brain response in the right supramarginal area of ALS patients might represent an altered sensitivity to social-emotional cues.

Executive Function Deficits in Acute Stroke

OBJECTIVES

To establish the frequency of executive dysfunction during acute hospitalization for stroke and to examine the relationship of that dysfunction to stroke severity and premorbid characteristics.

DESIGN

Inception cohort study.

SETTING

Inpatient wards at a Veterans Affairs hospital.

PARTICIPANTS

Consecutive sample of inpatients with radiologically or neurologically confirmed stroke. Final sample included 47 patients screened for aphasia and capable of neuropsychologic testing. Two nonstroke inpatient control samples (n=10 each) with either transient ischemic attack (TIA) or multiple stroke risk factors were administered the same research procedure and tests.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Composite cognitive impairment ratio (CIR), calculated from 8 scores indicative of executive function on 6 neuropsychologic tests by dividing number of tests completed into the number of scores falling below cutoff point, defined as 1.5 standard deviations below normative population mean.

RESULTS

Stroke patients had a mean CIR of .61, compared with .48 for TIAs and .44 for stroke-risk-only. Analysis of variance revealed that CIRs of stroke-risk-only patients but not TIAs were lower than those of the stroke patients (P=.02). Impairment frequencies were at least 50% for stroke patients on most test scores. The Symbol Digit Modalities Test (75% impairment) and a design fluency measure distinguished stroke from nonstroke patients. CIR was not related to stroke severity in the stroke patient sample, but was related to estimated premorbid intelligence.

CONCLUSIONS

Executive function deficits are common in stroke patients. The data suggest that limitations in information processing due to these deficits may require environmental and procedural accommodations to increase rehabilitation benefit.

Olfactory and auditory event-related potentials in Huntington's disease

The influence of Huntington's disease (HD) on the olfactory event-related potential (OERP), an electrophysiological measure of olfactory information processing, has not been reported to date. In the present study, olfactory and auditory event-related potentials (ERPs) were recorded monopolarly from Fz, Cz, and Pz electrode sites in 8 patients with HD and 8 age- and gender-matched control participants. Results demonstrated that individuals with HD were delayed compared with controls on the P3 component of the OERP (p<.001), with a trend toward a significant delay on the auditory ERP P3 (p<.06). The effect size for OERP P3 latency (pi(2)=.72) was larger than that for the auditory P3 (pi(2)=.24), which has previously been shown to be delayed in HD. Patients performed significantly worse than controls did on all neuropsychological measures. These measures significantly correlated with several components of the OERP. These findings extend the understanding of olfactory deficits in HD.

Emotional responding in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal disease, leaving the patient in a partially or completely deafferented state. In an explorative study, we investigated responses to visual socio-emotional stimuli in ALS patients. Pictures from the International Affective Picture System (IAPS) were verbally judged by 12 moderately affected ALS patients with a spinal onset and a slow progression and 18 age-matched controls, and data were compared with psychophysiological responses. Verbal emotional judgments of patients were more positive than ratings of controls. Regarding arousal, patients neutralized extreme pictures, in that they rated calm pictures as more exciting than controls and exciting pictures as more calm. These changes of emotional processing were unrelated to depression or frontal lobe dysfunction. There were no major differences between patients and controls concerning physiological responses to emotional stimuli. We conclude that emotional responses of ALS patients tend to be altered towards positive valence and towards a more balanced arousal state in early stages of the disease. These findings contradict assumptions of a generally negative impact of the disease on the emotional disposition and may indicate compensatory cognitive or neuroplastic changes.

The effects of chronic nicotine and alcohol use on neurocognitive function

Despite the extensive literatures on the independent effects of chronic nicotine and alcohol use on neurocognition, little is known about their combined impact. The purpose of this paper was to examine the effects of chronic nicotine and alcohol use on neurocognition in participants who took part in Project MATCH, a study of the efficacies of three behavioral treatments for adults diagnosed with alcohol abuse or dependence. Multiple regression and ANCOVA analyses were conducted to determine the relationship between lifetime weeks of tobacco use and years of alcohol use problems and neuropsychological test performance. Results showed that although years of chronic alcohol use was significantly inversely related to neuropsychological test scores, and chronic nicotine use showed an additive effect, substance use accounted for little variance in neuropsychological functioning. These findings suggest that some protective factors may have helped to attenuate the impact of chronic substance use on neurocognition. The importance of considering individual differences in such research is highlighted. Additional studies on the combined effects of chronic nicotine and alcohol use on neuropsychological function are warranted.

Cognitive and academic functioning in survivors of pediatric bone marrow transplantation

PURPOSE

To evaluate cognitive and academic functioning in survivors of pediatric bone marrow transplants (BMTs) at 1 and 3 years after a BMT.

PATIENTS AND METHODS

In a prospective, longitudinal design, patients underwent a comprehensive battery of neurocognitive measures before admission for transplantation and at 1, 3, and 5 years after a BMT. This article describes a cohort of 102 survivors with follow-up data available for 1 year after a BMT, including 54 survivors with follow-up available for 3 years. This represents the largest cohort of pediatric BMT survivors yet reported in a prospective study.

RESULTS

In the cohort as a whole, there were no significant changes on global measures of intelligence (intelligence quotient [IQ]) and academic achievement at either 1 or 3 years after a BMT, despite adequate power to detect an IQ change of three points or greater. Likewise, performance on specific tests of neuropsychologic function remained stable. No significant differences were observed between patients whose conditioning regimen included total-body irradiation (TBI) and those whose did not. The primary predictor of neurocognitive outcome was patient age, with younger patients more likely to show declines over time. The subset of patients who were less than 3 years of age at the time of transplantation seemed to be particularly vulnerable to cognitive sequelae.

CONCLUSION

The use of BMTs with or without TBI entails minimal risk of late neurocognitive sequelae in patients who are 6 years of age or older at the time of transplantation. However, patients who are less than 6 years of age at the time of transplantation, and particularly those less than 3 years of age, seem to be at some risk of cognitive declines.