Neuropsychological functioning in hemiparkinsonism

A standardized neuropsychological battery including measures of intellectual cognitive, memory, attention-concentration, language, abstraction and mental flexibility, and sensory and motor functions was administered to 21 hemiparkinsonian patients (14 with right side and 7 with left side symptoms) and 17 controls matched for age and education. Patients were impaired in all functions except sensory. For motor functions, impairment was ipsilateral to the side of symptoms. For cognitive functions, right side symptoms were associated with verbal deficits whereas left side symptoms were associated with spatial deficits. Thus, a pattern of neuropsychological deficits consistent with the lateralization of motor symptoms may appear in the early stages of the disease.     

Acute conduction aphasia: an analysis of 20 cases

In this study, the linguistic performance of 20 patients with acute conduction aphasia (CA) is described. CA presented as a relatively homogeneous aphasic syndrome characterized by a severe impairment of repetition and fluent expressive language functions with frequent phonemic paraphasias, repetitive self-corrections, word-finding difficulties, and paraphrasing. Language comprehension as assessed by tests of auditory and reading comprehension was only mildly impaired, whereas most patients performed poorly on the Token Test. Verbal-auditory short-term memory was reduced in all patients except one and seems to play a role in associated cognitive deficits, such as impaired syntactic comprehension or reduced mental arithmetics. A follow-up examination of 12 patients showed that CA often resulted in a chronic language deficit. Lesion locations were the posterior temporal and inferior parietal lobe.     

Profile of cognitive deficits and associations with depressive symptoms and intelligence in chronic early‐onset schizophrenia patients

Cognitive deficits in several domains have been demonstrated in early‐onset schizophrenia patients but their profile and relation to depressive symptoms and intelligence need further characterization. The purpose was to characterize the profile of cognitive deficits in chronic, early‐onset schizophrenia patients, assess the potential associations with depressive symptom severity, and examine whether cognitive deficits within several domains reflect intelligence impairments. This study compared attention, visual‐construction, aspects of visual and verbal memory, and executive functions in chronic, early‐onset schizophrenia patients (mean age = 20.7 years) (N = 18) and healthy controls (N = 38). Schizophrenia diagnoses were established at the time of the patients' first clinical presentation during childhood or adolescence and were confirmed five years later. In the chronic phase of early‐onset schizophrenia, significant deficits were observed in all specific cognitive functions. The profile of cognitive deficits was jagged, and visual‐construction, attention, and one aspect of verbal memory (verbal stories recall) were differentially impaired. Deficits of visual recall, visual recognition, and executive functions were accounted for by deficits in intelligence, while this was not the case for deficits of verbal recall of stories or attention. No significant associations were observed between the severity of cognitive deficits and that of depressive symptoms. Chronic, early‐onset schizophrenia is characterized by a broad and jagged profile of cognitive deficits. Deficits of attention and verbal recall of stories appear not to be accounted for by deficits in intelligence, and the severity of cognitive deficits seems independent from that of depressive symptoms     

Cognitive functioning after medial frontal lobe damage including the anterior cingulate cortex: a preliminary investigation

Two patients with medial frontal lobe damage involving the anterior cingulate cortex (ACC) performed a range of cognitive tasks, including tests of executive function and anterior attention. Both patients lesions extended beyond the ACC, therefore caution needs to be exerted in ascribing observed deficits to the ACC alone. Patient performance was compared with age and education matched healthy controls. Both patients showed intact intellectual, memory, and language abilities. No clear-cut abnormalities were noted in visuoperceptual functions. Speed of information processing was mildly reduced only in Patient 2 (bilateral ACC lesion). The patients demonstrated weak or impaired performance only on selective executive function tests. Performance on anterior attention tasks was satisfactory. We tentatively suggest that our findings are inconsistent with anterior attention theories of ACC function based on neuroimaging findings. We propose that the data may imply that the ACC does not have a central role in cognition. We speculate that our findings may be compatible with the view that the ACC integrates cognitive processing with autonomic functioning to guide behaviour.     

Neuropsychological Profile of Duchenne Muscular Dystrophy

In this study, subjects with Duchenne Muscular Dystrophy (DMD) were matched for age, verbal intelligence, and depression with a group of healthy control subjects. Neuropsychological testing was conducted to assess complex attention, language fluency, receptive language, and visuospatial cognition using tests that would not be affected by impaired motor skill. The subjects with DMD demonstrated poorer functioning on tests of complex attention, verbal fluency, and nonverbal memory functions, suggesting that the cognitive deficits in the DMD population may be specific rather than global in nature. Methodological issues salient to the assessment of intellectual functioning among subjects with DMD and the implications of these data for the further study of cognitive deficits in DMD are discussed.     

Memory deficits for non-amnestic mild cognitive impairment

Non-amnestic mild cognitive impairment (naMCI) is one of the clinical subtypes of mild cognitive impairment (MCI). However, the characteristics of memory deficits in naMCI as assessed by clinical neuropsychological evaluations are not clear. In this study, a battery of neuropsychological tests was administered to 122 cognitively normal controls (NC), 133 amnestic mild cognitive impairment (aMCI) patients, and 72 naMCI patients. The results showed that in individuals with naMCI, episodic memory, and other cognitive domains were impaired. The Prospective Memory Test (PMT) event-based prospective memory (EBPM), the Symbol Digit Modalities Test (SDMT) Accidental Memory, Stick test (ST) visuoconstructional memory, and ST Working Memory were impaired, yet did not reach the level of aMCI. Semantic memory was affected to a degree comparable with aMCI. Some functions like Auditory Verbal Learning Test (AVLT) recognition, and Judgment of Confidence (JOC) were maintained, as well as PMT Time-Based Prospective Memory (TBPM). This study verified that memory impairment among individuals with naMCI was mainly in memory functions mediated by the frontotemporal cortex.     

Cognitive estimations as a measure of executive dysfunction in childhood epilepsy

Children and adolescents with epilepsy are known to demonstrate executive function deficits. Despite prior work that has shown that cognitive estimation tasks are sensitive to executive dysfunction in children, such tasks have not been studied in children with epilepsy. This is particularly important given the fact that executive tasks have heretofore shown poor ecological validity, and it has been speculated that estimation tasks may show stronger ecological validity than other executive tests. One hundred and thirteen clinically referred children and adolescents with epilepsy were included. The Biber Cognitive Estimations Test was sensitive to cognitive dysfunction, with about half showing impairments on this task in comparison to age-matched normative data; the most frequently impaired subscales were quantity estimation and time estimation. Moreover, the Biber Cognitive Estimation Test showed moderate correlations with not only overall intellectual functions and academic achievement but also other commonly administered tests of executive functions, including digit span, Trailmaking, and the Tower of London but not with the contingency naming test. Cognitive estimations were also modestly correlated with age of epilepsy onset but not other epilepsy-severity variables such as number of antiepilepsy drugs (AEDs) or seizure frequency. Unfortunately, the hypothesis that the Biber Cognitive Estimation Test would show strong ecological validity was not supported, as it showed weak relations with parent-reported executive function deficits. The significance and limitations of this investigation are discussed.     

Neuropsychological findings and depressive symptoms in patients with Huntington''s disease

Twenty patients with Huntington's disease (HD) and a comparison group were studied by a depression scale (MADRS) and a neuropsychological test-battery assessing central areas of cognitive function. The main purpose was to analyze the consistency of findings across patients and focus on the role of specific factors in the impairments. The HD-patients are impaired relative to norms and the comparison-group in all areas but verbal conceptual function. We further divided the HD-patients into subgroups according to severity of neuropsychological impairment. The groups generally show a pattern of increasing deficits. Early changes are found in tests of cognitive efficiency, memory and sensomotor function, but the pattern of impairment is variable. The more severely affected subgroups show an increased decline in performance and progressive involvement of a broader range of functions. The pattern of depressive symptoms in HD-patients indicates that cognitive symptoms of concentration difficulties and lassitude are prominent in all subgroups.     

Subtle cognitive deficits in severe alcohol addicts – Do they show a specific profile?

Although alcohol dependency is a burden to society, data on cognitive performance in therapy‐resistant patients after multiple withdrawals are poor. In this study, 22 patients without reported cognitive deficits and 20 control subjects performed extensive cognitive testing and a motor task assessing short‐term memory. Patients displayed subtle deficits (mainly in executive function), while memory functions were relatively unimpaired. Our results suggest that subtle frontal‐executive deficits may contribute to a poor prognosis, but could be missed by routine clinical tests.     

Performance in normal subjects on a novel battery of driving-related sensory-motor and cognitive tests

Currently, there is no international standard for the assessment of fitness to drive for cognitively or physically impaired persons. A computerized battery of driving-related sensory-motor and cognitive tests (SMCTests) has been developed, comprising tests of visuoperception, visuomotor ability, complex attention, visual search, decision making, impulse control, planning, and divided attention. Construct validity analysis was conducted in 60 normal, healthy subjects and showed that, overall, the novel cognitive tests assessed cognitive functions similar to a set of standard neuropsychological tests. The novel tests were found to have greater perceived face validity for predicting on-road driving ability than was found in the equivalent standard tests. Test—retest stability and reliability of SMCTests measures, as well as correlations between SMCTests and on-road driving, were determined in a subset of 12 subjects. The majority of test measures were stable and reliable across two sessions, and significant correlations were found between on-road driving scores and measures from ballistic movement, footbrake reaction, hand-control reaction, and complex attention. The substantial face validity, construct validity, stability, and reliability of SMCTests, together with the battery’s level of correlation with on-road driving in normal subjects, strengthen our confidence in the ability of SMCTests to detect and identify sensory-motor and cognitive deficits related to unsafe driving and increased risk of accidents.     

Cognitive impairment in the early phase of multiple sclerosis and its relationship with mood, demographic and clinical variables

Our aim was to study cognitive performance in the early phase of MS. In addition, we studied whether depression, demographic and clinical variables differentiate cognitively impaired patients from non-impaired patients. A group of 52 MS-RR patients with mild level of neurological disability and 51 healthy controls were administered a comprehensive neuropsychological battery. The MS group performed significantly worse on several measures of attention and processing speed and visuoperceptive/visuoconstructive tasks. Verbal memory is characterized by working memory deficits, whereas the visual memory impairment is attributable to deficits in acquisition and consolidation/recuperation. Results shows that cognitive impairment is evident even in MS patients in the early course of their disease. Depression scores were higher in cognitively impaired patients as compared with unimpaired patients. The effect of educational level suggests that higher education delays the onset of cognitive decline.     

Cognitive deficits presenting as psychiatric symptoms in a patient with Moyamoya disease

The case of a middle-aged man who had intraventricular hemorrhages secondary to Moyamoya disease (MMD), and initially, presented with psychiatric symptoms which did not respond to treatment is described. Neuropsychological assessment showed underlying significant cognitive deficits, mostly of complex attention and speed of information processing, visuospatial and constructional abilities, verbal and nonverbal memory, and executive functions. These deficits remained stable or slightly improved in follow-up assessments. Cognitive dysfunction should be suspected in case of psychiatric or psychiatric-related symptoms in MMD patients. This case study in Greece highlights the range of preserved and impaired cognitive functions in adult MMD by means of repeated neuropsychological evaluations in which a broad range of cognitive abilities were assessed.     

The roles of sequencing and verbal working memory in sentence comprehension deficits in Parkinson's disease

Studies of sentence comprehension deficits in Parkinson's disease (PD) patients suggest that language processing involves circuits connecting subcortical and cortical regions. Anatomically segregated neural circuits appear to support different cognitive and motor functions. To investigate which functions are implicated in PD comprehension deficits, we tested comprehension, verbal working memory span, and cognitive set-switching in a non-linguistic task in 41 PD patients; we also obtained speech measurements reflecting motor sequencing processes that may be involved in articulatory rehearsal within working memory. Comprehension of sentences with center-embedded or final relative clauses was impaired when they could not be understood from lexical semantic content alone. Overall comprehension error rates correlated strongly with impaired set-switching and significantly with reduced working memory span and speech motor sequencing deficits. Correlations with comprehension of different sentence structures indicate that these impairments do not represent a single deficit; rather, PD comprehension deficits appear to arise from several independent mechanisms. Deficits in cognitive set-switching or underlying inhibitory processes may compromise the ability to process relative clauses. Deficits in verbal working memory appear to impair comprehension of long-distance dependencies. Speech sequencing correlated with neither set-switching nor verbal working memory span, consistent with their being supported by independent, segregated cortico-subcortical circuits.     

An investigation of organic factors in the neuropsychological functioning of patients with borderline personality disorder

The hypothesis to be tested in this study was that the cognitive deficits that have been documented in patients with Borderline Personality Disorder (BPD) are largely the consequence of organic insult, either developmental or acquired. Using a cross-sectional design, 80 subjects (males and females) who met the criteria for BPD participated in the study. They completed a battery of neuropsychological tests and a comprehensive interview assessing organic status as well as measures of the potentially confounding factors of current levels of depression and anxiety. It was expected that BPD-patients with a probable history of organic insult would perform significantly worse than would BPD patients without such a history. Analyses of the results provided partial support for the hypothesis. Subjects with both BPD and a history of organic insult were significantly more impaired on several measures including measures of attention than were BPD only subjects. The results suggested that the impaired cognitive performance of persons diagnosed with BPD may, in part, be attributed to organic factors.     

Decision-making impairments in patients with Parkinson's disease

A high percentage of Parkinson's disease (PD) patients show cognitive impairments in addition to the cardinal motor symptoms. These deficits primarily concern executive functions most probably linked to dysfunctions in prefrontal regions due to decreased dopaminergic transmission in fronto-striatal loops. To investigate possible associations between decision-making and executive functions in PD, we examined 20 non-demented PD patients and 20 healthy control subjects with a neuropsychological test battery and the Game of Dice Task. In this computerised decision-making task, the rules for gains and losses and the winning probabilities are obvious and stable. Thus, strategic components besides feedback processing might influence decision-making in this task. We found that PD patients were impaired in the Game of Dice task performance and that the frequency of disadvantageous choices correlated with both executive functions and feedback processing. We suggest that decision-making deficits of PD patients in explicit gambling situations might be associated with dysfunctions in two different fronto-striatal loops: the limbic-orbitofrontal-striatal loop, involved in feedback processing, and the dorsolateral prefrontal-striatal loop, involved in executive functions.     

One size does not fit all: face emotion processing impairments in semantic dementia, behavioural-variant frontotemporal dementia and Alzheimer's disease are mediated by distinct cognitive deficits

Patients with frontotemporal dementia (both behavioural variant [bvFTD] and semantic dementia [SD]) as well as those with Alzheimer's disease (AD) show deficits on tests of face emotion processing, yet the mechanisms underlying these deficits have rarely been explored. We compared groups of patients with bvFTD (n = 17), SD (n = 12) or AD (n = 20) to an age- and education-matched group of healthy control subjects (n = 36) on three face emotion processing tasks (Ekman 60, Emotion Matching and Emotion Selection) and found that all three patient groups were similarly impaired. Analyses of covariance employed to partial out the influences of language and perceptual impairments, which frequently co-occur in these patients, provided evidence of different underlying cognitive mechanisms. These analyses revealed that language impairments explained the original poor scores obtained by the SD patients on the Ekman 60 and Emotion Selection tasks, which involve verbal labels. Perceptual deficits contributed to Emotion Matching performance in the bvFTD and AD patients. Importantly, all groups remained impaired on one task or more following these analyses, denoting a primary emotion processing disturbance in these dementia syndromes. These findings highlight the multifactorial nature of emotion processing deficits in patients with dementia.     

Cognitive impairment and whole brain diffusion in patients with neuromyelitis optica after acute relapse

The objective of this study investigated cognitive impairments and their correlations with fractional anisotropy (FA) and mean diffusivity (MD) in patients with neuromyelitis optica (NMO) without visible lesions on conventional brain MRI during acute relapse. Twenty one patients with NMO and 21 normal control subjects received several cognitive tests to assess cognitive function. Head diffusion tensor imaging (DTI) of all patients with NMO were collected with a 3-T MR system. Correlations of cognitive test scores and whole brain FA and MD were examined by voxel-based analysis. Region-of-interest analysis was applied to the significantly correlated regions which the most frequently appeared. We found that NMO patients without visible brain lesions had significantly impaired learning and memory, decreased information processing speed, and damaged attention compared with normal control subjects. These impaired cognitive domains were significantly correlated with FA and MD in local regions of corpus callosum, anterior cingulate and medial frontal cortex. In corpus callosum of NMO patients, mean FA was significantly lower and mean MD higher than normal control subjects. Our findings suggest that cognitive impairments in learning and memory, information processing speed and attention occur in NMO patients without visible brain lesions during acute relapse. The impairments in immediate and short-term memory in NMO patients may be due to information encoding deficits in the process of information acquisition. The corpus callosum of such patients may have local microscopic damages that play a role in cognitive impairments during acute relapse.     

Perceptual functions in prosopagnosia

Some patients with prosopagnosia may have an apperceptive basis to their recognition defect. Perceptual abnormalities have been reported in single cases or small series, but the causal link of such deficits to prosopagnosia is unclear. Our goal was to identify candidate perceptual processes that might contribute to prosopagnosia, by subjecting several prosopagnosic patients to a battery of functions that may be necessary for accurate facial perception. We tested seven prosopagnosic patients. Three had unilateral right occipitotemporal lesions, two had bilateral posterior occipitotemporal lesions, and one had right anterior-to-occipital temporal damage along with a small left temporal lesion. These lesions all included the fusiform face area, in contrast to one patient with bilateral anterior temporal lesions. Most patients had impaired performance on face-matching tests and difficulty with subcategory judgments for non-face objects. The most consistent deficits in patients with lesions involving the fusiform face area were impaired perception of spatial relations in dot patterns and reduced contrast sensitivity in the 4 to 8 cycles deg(-1) range. Patients with bilateral lesions were impaired in saturation discrimination. Luminance discrimination was normal in all but two patients, and spatial resolution was uniformly spared. Curvature and line-orientation discrimination were impaired in only one patient, who also had the most difficulty with more basic-level object recognition. We conclude that deficits in luminance, spatial resolution, curvature, line orientation, and contrast at low spatial frequencies are unlikely to contribute to apperceptive prosopagnosia. More relevant may be contrast sensitivity at higher spatial frequencies and the analysis of object spatial structure. Deficits in these functions may impair perception of subtle variations in object shape, and may be one mechanism by which the recognition defect in prosopagnosia can extend to other classes of object subcategorization.     

Comprehensive driving assessment: neuropsychological testing and on-road evaluation of brain injured patients

The study investigates the correspondence between neuropsychological test results and on-road driving performance among 55 patients with a CT-verified brain damage or documented neurological disorder (cerebrovascular accident: 43, traumatic brain injury: 5, multiple sclerosis: 4, other: 3). 5 patients showed unimpaired test profiles and passed the on-road evaluation. 18 patients showed severe neuropsychological deficits contrary to driving and were not recommended for on-road evaluation. Of the remaining 32 patients with some neuropsychological deficits, all 100% in the minor impaired group (n = 8) passed the driving evaluation, compared to 69% in the mildly impaired (n = 16) and 38% in the moderately impaired group (n = 8). Measures of reduced visuoconstructive ability, reaction time, visual attention, and awareness of cognitive impairments, were found to discriminate between groups. It is concluded that neuropsychological assessment of targeted functions provide an ecological valid prediction of driving skill after brain damage, but that on-road evaluation is needed as supplement in cases with ambiguous test findings.