Cognitive effects of unilateral posteroventral pallidotomy: a 4-year follow-up study.

We assessed the long-term neuropsychological effects of unilateral posteroventral pallidotomy in Parkinson's disease. Eleven Parkinson's disease patients, from an original cohort of 15 consecutive patients who underwent pallidotomy, were evaluated. A neuropsychological battery was administered to each patient before (3 days) and after (3 months and 4 years) surgery during the effects of levodopa. The following tests were administered: Rey's Auditory-Verbal Learning Test, Visual Associative Learning test from the Wechsler Memory Scale-Revised, Luria's motor alternation, Benton's Judgment of Line Orientation, Trail Making, phonetic verbal fluency, Stroop test, Petrides' working memory tasks, Beck's depression questionnaire and the Maudsley obsessional-compulsive inventory. In the 3-month postoperative assessment, there was a significant worsening in phonetic verbal fluency and an improvement in Benton's Judgment of Line Orientation test. In the 4-year follow-up assessment, phonetic verbal fluency and Benton's Judgment of Line Orientation test returned to baseline scores. Although there was no significant difference between pre- and postsurgical scores for long-term visual associative memory, there was a significant deterioration between 3-month and 4-year follow-up performances. Our results suggest that unilateral posteroventral pallidotomy may produce transient changes in prefrontal and visuospatial functions, but there is no evidence of permanent neuropsychological effects.     

Neuropsychological outcome after unilateral pallidotomy for the treatment of Parkinson's disease

OBJECTIVE: To assess the long term cognitive outcome of unilateral posteroventral pallidotomy (PVP) and the overall efficacy of the surgery. METHODS: Forty two (29 left and 13 right PVP) patients with Parkinson's disease underwent neurological and neuropsychological testing before PVP and at 3 and 12 months after PVP. The neuropsychological testing battery emphasised measures of verbal learning and memory, visuospatial abilities, speed of information processing, executive functioning, and affective functioning. RESULTS: All patients demonstrated motor improvements after surgery during their off state, and 86% of patients also showed improvements in motor functioning in their on state. Repeated measures ANOVA showed significant improvements in confrontational naming, visuospatial organisation, and affective functioning 3 months and 12 months after surgery, with inconsistent improvements in executive functioning 12 months post-PVP. Patients demonstrated a transient impairment in verbal memory, with verbal learning performance returning to baseline 12 months post-PVP after a significant decline 3 months after PVP. When three patients with lesions extending outside of the PVP were excluded from the analysis, a decline in verbal fluency performance after PVP was not found to be significant. Differences due to side of lesion placement were not found on any of the cognitive measures. CONCLUSIONS: In the largest long term follow up study reported to date, the cognitive changes found up to a year after PVP are minimal compared with the robust improvements in motor function. The findings highlight the need to investigate the relation between the specific fibre tracts affected by the lesions and cognitive outcome.     

Depressed mood and memory impairment before and after unilateral posteroventral pallidotomy in Parkinson's disease

This study evaluated poor mood state as a moderator of changes in verbal recall ability from before to after unilateral posteroventral pallidotomy in 54 individuals with advanced Parkinson's disease. Repeated-measures analysis of covariance (controlling for motor disease severity) indicated that left-posteroventral pallidotomy subjects with depressed mood performed more poorly on measures of verbal list learning and story recall compared to nondepressed subjects or right-posteroventral pallidotomy subjects with depressed mood both before and after surgery. The results suggest that depressed mood should be taken into account when interpreting memory test performance in Parkinson's disease surgical candidates both before and after surgery.     

Unilateral pallidotomy in PD: a controlled study of cognitive and behavioral effects. The Netherlands Pallidotomy Study (NEPAS) group

OBJECTIVE: To investigate whether unilateral pallidotomy affects cognitive and behavioral functioning. METHODS: At baseline and after 6 months we assessed neuropsychological functioning in 35 patients with advanced PD. After baseline examination, patients were randomized to pallidotomy within 1 month (6 left-sided, 13 right-sided) or to pallidotomy after follow-up assessment 6 months later (n = 16; control group). We performed neuropsychological tests of language, visuospatial function, memory, attention, and executive functions. Self ratings and proxy ratings of memory problems and dysexecutive symptoms were also collected. RESULTS: No significant differences over time were found between pallidotomy and control groups, with the exception of a decrease of verbal fluency in the left-sided pallidotomy group. CONCLUSIONS: Unilateral pallidotomy is relatively safe with respect to cognition and behavior. Left-sided pallidotomy may lead to minor deterioration in verbal fluency. The sample size of this study is too small, however, to rule out the possibility of infrequent but clinically important side effects.     

Effects of pallidotomy and bilateral subthalamic stimulation on cognitive function in Parkinson disease

Unilateral pallidotomy and bilateral subthalamic deep brain stimulation (STN-DBS) for Parkinsons disease (PD) have demonstrated a positive effect on motor functions. However, further studies are needed of the unintended cognitive effects accompanying these new surgical procedures. We studied the consequences of unilateral pallidotomy and STN-DBS on cognitive function in a controlled comparative design. Sixteen consecutive PD patients were assessed before and 6 months after unilateral pallidotomy (n = 8) and bilateral STN-DBS (n = 8). The same assessments were performed in a control group of eight non-operated matched PD patients recruited from surgery candidates who refused operation. The neuropsychological battery consisted of test measuring memory, attention, arithmetic, problem solving and language, as well as visuospatial, executive and premotor functions. An analysis of variance (factors time and treatment) was applied. No statistically significant differences were found in the presurgical evaluation of clinical and demographic data for the three treatment groups. The controlled comparison between presurgical and postsurgical performance revealed no significant changes in the cognitive domains tested in the pallidotomy group. The STN-DBS group showed a selective significant worsening of semantic verbal fluency (p = 0.005). This controlled comparative study suggests that neither unilateral pallidotomy nor bilateral STN-DBS have global adverse cognitive consequences, but bilateral STN-DBS may cause a selective decrease in verbal fluency.     

微电极引导的苍白球鼠损术对帕金森病患者认知功能的近期影响

目的：了解微电极引导的腹侧苍白球毁损术（PVP）对帕金森病（PD）患者认知功能的影响,方法：对接受PVP治疗的20例PD患者手术前后进行认知功能检查,临床记忆量表、线方向判断测验、言主流畅性及简明精神状态量表检查。结果：左侧PVP患者术后临床记忆量表联想学习分测验成绩较术前显著减退（P＜0．05）,其余记忆分测验、记忆商以及其他认知检查手术前后无显著改变（P＞0．05）;右侧PVP患者术后较术前各项检查成绩无明显改变（P＞0．05）,手术后运动功能较术前显著改善（P＜0．05）。结论左侧苍白球参与了语言记忆,PVP对所检查的认知功能影响轻微。     

Impaired motor speed, visuospatial episodic memory and verbal fluency characterize cognition in long-term stroke survivors: the Tromsø Study

The cognitive function after stroke is examined in acute and subacute phase, but poorly characterized in long-term stroke survivors. This paper discusses cognitive function among long-term stroke survivors, with matched stroke-free subjects, based on a population survey. General cognition, verbal, executive and visuospatial function, memory, attention, and motor speed were tested as well as motor function in upper extremities. Stroke survivors and controls were most effectively discriminated by means of motor speed, followed by visuospatial episodic memory and verbal fluency. This pattern of cognitive disturbances may be a consequence of cerebral lesions in frontal subcortical areas, and is different from Alzheimer's disease.     

Neuropsychological and psychiatric sequelae of pallidotomy for PD: clinical trial findings

OBJECTIVE: To evaluate the neuropsychological and psychiatric sequelae of unilateral posterior pallidotomy for treatment of PD. METHODS: Patients with idiopathic PD completed baseline and 3- and 6-month assessments after random assignment to an immediate surgery (n = 17) or medical management (n = 16) group. RESULTS: Compared with the medical management group, the immediate surgery group with single lesions centered on the posterior internal pallidum showed superior naming and response inhibition, better verbal recall at 6 months, but greater distractibility, a tendency toward lower phonemic fluency, and a transient (3 months' only) semantic fluency deficit. The group with left lesions had more neuropsychological deficits than the group with right lesions or the medical management group, although these occurred mainly at 3 (but not 6) months. At 6 months, the patients with left lesions showed better verbal memory retention than the patients with right lesions. On most measures, the pattern of individual clinical change did not differ as a function of surgery or lesion laterality, with the exception of a higher frequency of decline in phonemic fluency in the patients with left lesions at 6 months. Although psychiatric status did not change overall, a history of depression tended to increase the risk of a depressive episode following surgery. CONCLUSIONS: Well-targeted, uncomplicated, unilateral pallidotomy does not produce overall neuropsychological or psychiatric change, although there are subtle changes on specific measures sensitive to frontal lobe function.     

Motor and cognitive sequelae of unilateral pallidotomy in intractable Parkinson's Disease: electronic measurement of motor steadiness is a useful outcome measure

This study examined the short-term motor and cognitive sequelae of unilateral posterolateral pallidotomy for patients with intractable Parkinson's Disease (PD). Unique to this study was the inclusion of electronic motor steadiness instrumentation among pre- and postsurgical assessment procedures. Fifteen PD patients underwent right-sided surgery and 10 underwent left-sided surgery; patients were evaluated 1 month presurgery and approximately 3 months postsurgery. Motorically, there were no significant changes in grooved pegboard or maze-drawing performances, but patients evidenced significantly improved steadiness, particularly in the hand contralateral to the side of surgery. Cognitively, there were no significant decrements on postsurgery composite variables comprised of well-known tests of attention, executive functioning, delayed memory or recognition memory; these findings were similar for patients with either left- or right-sided surgery. There was, however, a significant change in language abilities among a subset of patients. This change was evident in the decline in verbal fluency in PD patients who underwent left-sided pallidotomy, a finding that has consistently emerged in pallidotomy outcome studies. This decline is discussed in terms of evidence that suggests that the basal ganglia consist of several separate, but parallel circuits, some of which are important for cognition.     

Neuropsychological sequelae of bilateral posteroventral pallidotomy

OBJECTIVES: To document the impact of bilateral posteroventral pallidotomy on cognitive status. METHODS: 17 patients with Parkinson's disease were evaluated with a neuropsychological battery before and six months after bilateral pallidotomy. A comparison group (n = 8) was also assessed at six month intervals. Outcome variables were tests of memory, language, visuospatial function, attention, executive skills, and depression. RESULTS: Despite a large number of variables studied, a significant postsurgical change was found only in performance of the tower of London task, a measure of planning abilities. The effect size of this change was larger than that of the comparison group, and a reliable change index score established that 5 of 13 surgical patients had statistically reliable reductions in planning performance. CONCLUSIONS: Patients with a young age of onset and long duration of Parkinson's disease who underwent bilateral pallidotomy had a relatively circumscribed reduction in neuropsychological functioning, being limited to motor planning efficiency. These data suggest that the cognitive role of the posteroventral globus pallidus is limited, at least in people with Parkinson's disease.     

One-year double-blind study of the neurocognitive efficacy of olanzapine, risperidone, and haloperidol in schizophrenia

Neurocognitive deficits in schizophrenia can reach 1 to 2 standard deviations below healthy controls. The comparative effect of typical and atypical antipsychotic medications on neurocognition is controversial, and based primarily on studies with small samples and large doses of typical comparator medications. The present study assessed neurocognitive efficacy. It was hypothesized that olanzapine treatment would improve neurocognitive deficits to a greater degree than either risperidone or haloperidol treatment. This was a double-blind, randomized, controlled, parallel study with neurocognition assessed at baseline, and 8, 24, and 52 weeks. Per protocol, the haloperidol arm was discontinued. Four hundred and fourteen inpatients or outpatients with schizophrenia and schizoaffective disorder were treated with oral olanzapine (n = 159), risperidone (n = 158), or haloperidol (n = 97). Individual domains (executive function, learning and memory, processing speed, attention/vigilance, verbal working memory, verbal fluency, motor function, and visuospatial ability) were transformed into composite scores and compared between treatment groups. At the 52-week endpoint, neurocognition significantly improved in each group (p < 0.01 for olanzapine and risperidone, p = 0.04 for haloperidol), with no significant differences between groups. Olanzapine- and risperidone-treated patients significantly (p < 0.05) improved on domains of executive function, learning/memory, processing speed, attention/vigilance, verbal working memory, and motor functions. Additionally, risperidone-treated patients improved on domains of visuospatial memory. Haloperidol-treated patients improved only on domains of learning/memory. However, patients able to remain in treatment for the entire 52 weeks benefited more from olanzapine or risperidone treatment than haloperidol treatment.     

Neuropsychological test performance in social anxiety disorder

Abstract

Background: The effect of state factors on neuropsychological performance in social anxiety disorder (SAD) has not been thoroughly investigated and the overall neuropsychological profile remains poorly understood. Aims: The primary objective of the study was to investigate the effect of state anxiety and state emotion suppression on neuropsychological performance in SAD. Methods: A neuropsychological test battery was administered before and after an anxiety manipulation (instruction to give a video-recorded speech) to 42 patients with SAD and to a gender and education matched group of 42 healthy controls (HCs). Results: Overall, participants with SAD performed worse than HCs on processing speed, visuospatial construction, visuospatial memory, verbal learning and word fluency, of which only the decreased visuospatial construction performance was considered clinically significant. State anxiety was not associated with neuropsychological performance at baseline, whereas state emotion suppression predicted decreased visuospatial memory in HCs and decreased verbal learning in the SAD group. Both groups performed better on working memory, processing speed and spatial anticipation, and worse on verbal learning and memory following the anxiety manipulation. The increase in state anxiety was associated with the decrease in verbal learning in both groups. Conclusions: Participants with SAD showed clinically significant difficulties with visuospatial construction and may experience verbal learning difficulties when suppressing emotions and experiencing an increase in anxiety.     

Motor and Cognitive Sequelae of Unilateral Pallidotomy in Intractable Parkinson's Disease: Electronic Measurement of Motor Steadiness is a Useful Outcome Measure

This study examined the short-term motor and cognitive sequelae of unilateral posterolateral pallidotomy for patients with intractable Parkinson's Disease (PD). Unique to this study was the inclusion of electronic motor steadiness instrumentation among pre- and postsurgical assessment procedures. Fifteen PD patients underwent right-sided surgery and 10 underwent left-sided surgery; patients were evaluated 1 month presurgery and approximately 3 months postsurgery. Motorically, there were no significant changes in grooved pegboard or maze-drawing performances, but patients evidenced significantly improved steadiness, particularly in the hand contralateral to the side of surgery. Cognitively, there were no significant decrements on postsurgery composite variables comprised of well-known tests of attention, executive functioning, delayed memory or recognition memory; these findings were similar for patients with either left- or right-sided surgery. There was, however, a significant change in language abilities among a subset of patients. This change was evident in the decline in verbal fluency in PD patients who underwent left-sided pallidotomy, a finding that has consistently emerged in pallidotomy outcome studies. This decline is discussed in terms of evidence that suggests that the basal ganglia consist of several separate, but parallel circuits, some of which are important for cognition.     

Cognitive functions in carotid artery disease before endarterectomy

Restorative effects of carotid endarterectomy (CEA) on cognitive functioning in patients with severe atherosclerotic disease presuppose the existence of cognitive deficits prior to the intervention. Thorough examination of this premise received only minor attention. The present study assessed symptomatic and asymptomatic patients with severe unilateral or bilateral stenosis of the carotid arteries one day before CEA. Healthy volunteers with similar demographic characteristics served as control subjects. Patients overall showed decreased functioning on tests of attention, verbal and visual memory, verbal fluency, and psychomotor speed and executive functioning, even after correction for the effects of mood. Simple motor skills and visuospatial functioning were not affected. Patients grouped according to presence and type of previous clinical symptoms and severity of contralateral stenosis only slightly differed from each other. The findings leave open the potential of improving cognitive function after CEA.     

Qualitative analysis of verbal fluency before and after unilateral pallidotomy

This study examined qualitative aspects of phonemic and semantic fluency before and after unilateral pallidotomy in patients with intractable Parkinson's Disease (PD). Specifically, clustering (number of similar words generated sequentially) and switching (number of changes or switches from one cluster to another) were evaluated for both fluency tasks. Twenty-five PD patients participated and were grouped according to whether they improved or declined on each of the fluency measures after surgery. Decliners evidenced decreased switching, but not clustering, suggesting difficulties with set-shifting and cognitive flexibility rather than a diminished semantic store of information or retrieval difficulties. Though consistent with hypotheses about difficulties with executive processing after pallidotomy, a series of correlational analyses with composite measures of neuropsychological functioning (attention, language, executive processing, and memory) suggest caution in interpreting these findings. In these analyses, clustering was not meaningfully related to any of the composites whereas switching was significantly and positively related to the composites; this pattern emerged, for the most part, on both fluency measures before and after surgery. Switching, but not clustering, was also significantly and positively correlated with total words generated on both semantic and phonemic fluency. Switching changes across time were also related to DRS changes post-pallidotomy. These correlational analyses challenge the specificity of the switching variable and, more broadly, the validity of these qualitative measures of verbal fluency.     

Deep versus Periventricular White Matter Lesions and Cognitive Function in a Community Sample of Middle-Aged Participants

The association of cerebral white matter lesions (WMLs) with cognitive status is not well understood in middle-aged individuals. Our aim was to determine the specific contribution of periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs) to cognitive function in a community sample of asymptomatic participants aged 50 to 65 years. One hundred stroke- and dementia-free adults completed a comprehensive neuropsychological battery and brain MRI protocol. Participants were classified according to PVH and DWMH scores (Fazekas scale). We dichotomized our sample into low grade WMLs (participants without or with mild lesions) and high grade WMLs (participants with moderate or severe lesions). Analyses were performed separately in PVH and DWMH groups. High grade DWMHs were associated with significantly lower scores in executive functioning (-0.45 standard deviations [SD]), attention (-0.42 SD), verbal fluency (-0.68 SD), visual memory (-0.52 SD), visuospatial skills (-0.79 SD), and psychomotor speed (-0.46 SD). Further analyses revealed that high grade DWMHs were also associated with a three- to fourfold increased risk of impaired scores (i.e.,<1.5 SD) in executive functioning, verbal fluency, visuospatial skills, and psychomotor speed. Our findings suggest that only DWMHs, not PVHs, are related to diminished cognitive function in middle-aged individuals. (JINS, 2012, 18, 1-12).     

Effects of bilateral posteroventral pallidotomy on gait of subjects with Parkinson disease

BACKGROUND: Most studies documenting the effect of pallidotomy on parkinsonian gait have reported unilateral surgery and used qualitative scales or timed tests that only provide measures of walking speed. OBJECTIVE: To document the effect of bilateral posteroventral pallidotomy on the walking patterns of patients with Parkinson disease (PD). DESIGN: Case series of gait evaluations performed 1 month before and 1 month after surgery, with antiparkinson medication withheld for 8 hours overnight. SETTING: Movement analysis laboratory of a clinical research center. PATIENTS: Consecutive sample of 8 men and 3 women with a diagnosis of PD scheduled for bilateral pallidotomy. INTERVENTION: Bilateral posteroventral pallidotomy. MAIN OUTCOME MEASURES: A 3-dimensional motion-capture system allowed calculation of temporal and spatial measurements and joint angular displacements of the lower extremities and trunk during gait. RESULTS: Pallidotomy significantly increased average walking speed from 0.214 statures/s preoperatively to 0.440 statures/s postoperatively (where stature indicates body height) (P = .03). A faster postoperative walking speed was achieved almost exclusively by increasing average stride length from 0.24 to 0.47 statures (P = .03) rather than changing average gait cycle time (1.32 to 1.37 seconds; P = .08). A forward stepwise multiple regression analysis (P<.001) revealed that 96% of the change in stride length postoperatively could be explained by the combination of changes in foot-floor angle, knee, and hip excursion during gait. CONCLUSIONS: Bilateral posteroventral pallidotomy was associated with a 2-fold increase in walking speed. Previous studies have demonstrated that walking speed is an important indicator of locomotor performance and level of disability in patients with PD, so the increase in postoperative walking speed likely provided a functional benefit.     

Motor circuitry re-organization after pallidotomy in Parkinson disease: a neurophysiological study of the bereitschaftspotential, contingent negative variation, and N30.

The aim of the study was to evaluate the reorganization changes in the motor circuitry of the basal ganglia following unilateral posteroventral pallidotomy in Parkinson disease (PD) patients using neurophysiological paradigms. Eight advanced PD patients received a neurophysiological battery 2 months prior and 6 months after unilateral pallidotomy. Examinations were all performed in the practically defined "off" situation. Bereitschaftspotential (BP) and N30 were recorded for each hand alternately. Contingent negative variation (CNV) was obtained using a visual Go/no-Go paradigm. ANOVAs (electrode position; surgery) were applied for BP and CNV results. N30 data were analyzed using Wilcoxon matched-pair tests. A significant increase in amplitude of the late component (NS') of the BP was evidenced with patient performing with the hand contralateral to pallidotomy. No significant amplitude differences were found in CNV after surgery in any lead, or in any of the time windows tested. A trend toward significance was observed corresponding to a postsurgical numerical increase in amplitude of the N30 peak in the hand contralateral to pallidotomy. These results suggest that neurophysiological changes after pallidotomy are mainly in the last stages of movement preparation and execution.     

The neuropsychological profile of symptomatic AIDS and ADC patients in the pre-HAART era: a meta-analysis.

It remains essential to document the neuropsychological profile of acquired immunodeficiency syndrome (AIDS) dementia complex (ADC) and minor forms human immunodeficiency virus (HIV)-associated neurocognitive impairment by quantifying the magnitude of impairment across eras of treatment. Indeed, with the introduction of the highly active antiretroviral therapy (HAART), there is evidence of changes in aspects of ADC. To allow quantitative and qualitative comparisons with the HAART era studies, we developed a summary of neuropsychological performance acquired in pre-HAART era studies in advanced HIV infection and ADC. Using a meta-analytical procedure and a test nomenclature that accounts for task complexity, we found that individuals with symptomatic infection (but no AIDS) demonstrated a global mild level of cognitive impairment, except for the domains complex attention/psychomotor speed, motor coordination, and learning, which showed moderate impairment. Individuals with AIDS demonstrated a global moderate level of cognitive impairment with a predominance of deficits in attention, complex attention/psychomotor speed, learning, motor coordination, with additional deficits in verbal memory and reasoning. Individuals with ADC demonstrated the most severe cognitive disturbances in domains of learning, motor coordination, with additional deficits in veibal fluency and verbal memory. Moderate impairment was evidenced in domains of complex attention/psychomotor speed, whereas naming and visuospatial functions were relatively preserved. The profile of deficits in ADC suggests that it may not be only interpreted as a worsening form of the impairment that is seen in the AIDS and symptomatic stages of HIV disease but that there are also additional deficits suggestive of an alternate pathogenetic process(es).     

Unilateral pallidotomy versus bilateral subthalamic nucleus stimulation in PD

Abstract Objective To compare the cognitive and behavioural effects of unilateral pallidotomy and bilateral subthalamic nucleus (STN) stimulation. Methods After baseline examination 34 patients were randomly assigned to unilateral pallidotomy (4 left-sided, 10 right-sided) or bilateral STN stimulation (n=20). At baseline and six and twelve months after surgery we administered neuropsychological tests of language, memory, visuospatial function, mental speed and executive functions. Also a depression rating scale, and self and proxy ratings of memory and dysexecutive symptoms were administered. Results Six months after surgery, the STN group and the pallidotomy group differed significantly in change from baseline in number of errors on two tests of executive functioning. After 12 months the STN group reported less positive affect compared with baseline than the pallidotomy group. One patient in the STN group showed an overall cognitive deterioration due to complications. Conclusions Although we need larger groups to draw firm conclusions, our results suggest that bilateral STN stimulation has slightly more negative effects on executive functioning than unilateral pallidotomy.