Executive Dysfunction, Social Cognition Impairment, and Gray Matter Pathology in Myotonic Dystrophy Type 2: A Pilot Study.

BACKGROUND: In contrast to myotonic dystrophy type 1, the cognitive and radiologic profile of myotonic dystrophy type 2 (DM2) is relatively poorly characterized. OBJECTIVE: To conduct a pilot study to systematically evaluate cognitive and radiologic features in a cohort of Greek individuals with DM2. METHOD: Eleven genetically confirmed individuals with DM2 and 26 age- and education-matched healthy controls were administered the Edinburgh Cognitive and Behavioural Amyotrophic Lateral Sclerosis Screen (ECAS) to screen for impairment in multiple cognitive domains. MRI data were evaluated by morphometric analyses to identify disease-specific gray and white matter alterations. The following statistical thresholds were used for cognitive comparisons: PFDR < 0.05 and Bayes factor (BF 10 ) >10. RESULTS: The DM2 group exhibited cognitive impairment (ECAS Total score; PFDR = 0.001; BF 10 = 108.887), which was dominated by executive impairment ( PFDR = 0.003; BF 10 = 25.330). A trend toward verbal fluency impairment was also identified. No significant impairments in memory, language, or visuospatial function were captured. The analysis of subscores revealed severe impairments in social cognition and alternation. Voxel-based morphometry identified widespread frontal, occipital, and subcortical gray matter atrophy, including the left superior medial frontal gyrus, right medial orbitofrontal gyrus, right operculum, right precuneus, bilateral fusiform gyri, and bilateral thalami. CONCLUSION: DM2 may be associated with multifocal cortical and thalamic atrophy, which is likely to underpin the range of cognitive manifestations mostly characterized by executive impairment and specifically by impaired social cognition.

Neuropsychological Assessment Should Always be Considered in Myotonic Dystrophy Type 2.

Myotonic dystrophies (DMs) are hereditary, multisystem, slowly progressive myopathies. One of the systems they affect is the CNS. In contrast to the well-established cognitive profile of myotonic dystrophy type 1 (DM1), only a few studies have investigated cognitive dysfunction in individuals with myotonic dystrophy type 2 (DM2), and their findings have been inconsistent. To identify the most commonly affected cognitive domains in individuals with DM2, we performed a formal comprehensive review of published DM2 studies. Using the terms "myotonic dystrophy type 2" AND "cognitive deficits," "cognitive," "cognition," "neuropsychological," "neurocognitive," and "neurobehavioral" in all fields, we conducted an advanced search on PubMed. We read and evaluated all of the available original research articles (13) and one case study, 14 in total, and included them in our review. Most of the research studies of DM2 reported primary cognitive deficits in executive functions (dysexecutive syndrome), memory (short-term nonverbal, verbal episodic memory), visuospatial/constructive-motor functions, and attention and processing speed; language was rarely reported to be affected. Based on the few neuroimaging and/or multimodal DM2 studies we could find, the cognitive profile of DM2 is associated with brain abnormalities in several secondary and high-order cortical and subcortical regions and associative white matter tracts. The limited sample size of individuals with DM2 was the most prominent limitation of these studies. The multifaceted profile of cognitive deficits found in individuals with DM2 highlights the need for routine neuropsychological assessment at both baseline and follow-up, which could unveil these individuals' cognitive strengths and deficits.

Pesticide exposure and cognitive function: Results from the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD).

BACKGROUND: Results from studies to date, regarding the role of chronic pesticide exposure on cognitive function remain contradictory. OBJECTIVE: To investigate the relationship between self-reported pesticide exposure and cognitive function. METHODS: Data from a population-based cohort study of older adults (HEllenic Longitudinal Investigation of Aging and Diet) in Greece was used. Pesticide exposure classification was based on 1) living in areas that were being sprayed; 2) application of spray insecticides/pesticides in their gardens; and 3) occupational application of sprays. Associations between z-scores of cognitive performance and self-reported pesticide exposure were examined with linear regression analyses. Adjusted models were applied, for all analyses. RESULTS: Non-demented individuals who reported that they had been living in areas near sprayed fields, had poorer neuropsychological performance, compared to those who had never lived in such areas. Sub-analyses revealed poorer performance in language, executive and visual-spatial functioning, and attention. These associations remained after a sensitivity analysis excluding subjects with mild cognitive impairment. CONCLUSION: Self-reported exposure to pesticides was negatively associated with cognitive performance.

The performance of patients with Parkinson's disease on the Face-Name Associative Memory Examination.

In this study, we examined the performance of patients with Parkinson's disease (PD) with different cognitive profiles on the Face-Name Associative Memory Examination (FNAME). We evaluated 71 patients with a comprehensive neuropsychological battery. The results revealed that the group with executive and additional visuospatial deficits demonstrated significantly lower scores on FNAME. This finding indicates the possible clinical utility of FNAME for screening patients with PD with distinct cognitive profiles. Further longitudinal studies are needed to consider the prognostic adequacy of FNAME in detecting high-risk Parkinson's disease dementia (PDD).

Endogenous sex hormones and memory performance in middle-aged Greek women with subjective memory complaints.

The changing hormonal milieu during the menopausal transition may contribute to the development of memory disorders. We aimed to assess the association of sex hormones with memory function in a sample of Greek middle-aged women. This pilot study included 44 women with subjective memory complaints. Memory performance was evaluated using the Hopkins Verbal Learning Test (HVLT), the Brief Visuospatial Memory test (BVMT), and the verbal digits backwards test (VSPAN), to assess verbal, visuospatial, and working memory performance, respectively. Menopausal symptoms were assessed using the Green Climacteric Scale. VSPAN backwards scores were positively associated with log-transformed free androgen index (logFAI), in models adjusted for age, education, log-transformed free estrogen index (logFEI), hypertension, and the intensity of menopausal symptoms. BVMT total scores were predicted by logFAI (b-coefficient = 0.424, p value = 0.002), education, and combined climacteric symptomatology, in a model adjusted for age, logFEI, and hypertension. Women with circulating estradiol above the median value of 10 pg/mL had better total HTLV total scores compared to women with estradiol values below the median (HTLV total scores, estradiol ≤ 10 pg/mL vs. > 10 pg/mL: 24.2 ± 3.6 vs. 30.0 ± 7.9, p value = 0.007 unadjusted). This association was affected by education and remained independent of menopausal symptoms and testosterone levels, education, and hypertension (model R 2 = 22.3%; b-coefficient = 0.318, p value = 0.024). Endogenous total estradiol is associated with verbal episodic memory, while logFAI is associated with working memory performance and visuospatial episodic memory in this sample of postmenopausal women. These associations were not influenced by age, education, or menopausal symptoms. Larger studies are necessary to evaluate the significance of our findings.

Verbal and Figural Fluency in Temporal Lobe Epilepsy: Does Hippocampal Sclerosis Affect Performance?

BACKGROUND AND OBJECTIVES: Clinicians commonly use verbal and nonverbal measures to test fluency in patients with epilepsy, either during routine cognitive assessment or as part of pre- and postsurgical evaluation. We hypothesized that patients with mesial temporal lobe epilepsy (TLE) with hippocampal sclerosis would perform worse than patients with lateral TLE in both verbal and design fluency. METHODS: We assessed semantic, phonemic, and nonverbal fluency in 49 patients with TLE: 31 with lateral TLE and 18 with mesial TLE plus hippocampal sclerosis. We also gave non-fluency cognitive measures: psychomotor speed, attentional set shifting, selective attention, abstract reasoning, verbal and visual episodic memory, and incidental memory. RESULTS: Patients with mesial TLE performed significantly worse on figural fluency than patients with lateral TLE. Even though group differences on verbal fluency measures were not significant, the patients with mesial TLE had a pattern of poorer performance. The patients with mesial TLE scored significantly worse on measures of selective attention, verbal episodic memory, and incidental memory. CONCLUSIONS: Our study underlines differences in cognitive function between patients with mesial and lateral TLE, particularly in figural fluency. Although we cannot directly assess the role of the hippocampus in cognitive aspects of creative and divergent thinking related to figural fluency, the cognitive discrepancies between these two TLE groups could be ascribed to the mesial TLE hippocampal pathology shown in our study and addressed in the literature on hippocampal involvement in divergent thinking. Our findings could benefit cognitive rehabilitation programs tailored to the needs of patients with TLE.

Determinants of stigma in a cohort of hellenic patients suffering from multiple sclerosis: a cross-sectional study.

BACKGROUND: Patients suffering from several neurologic disorders may bear the "stigma" of their disease, being disqualified from full social acceptance. Although stigma is considered to be present in Multiple Sclerosis (MS), the factors that influence its levels are ambiguous. Aim of our study was to examine, for the first time in the literature, the basic determinants of stigma in a Hellenic MS-patients cohort, as well as how stigma affects their Quality-of-Life (QoL) profiles. METHODS: Three hundred forty two patients were recruited in this study. Data collected concerned sociodemographic and disease-related variables, mental illness assessment, Multiple-Sclerosis-QoL-54 (MSQoL-54) and Stigma-Scale-for-Chronic-Illness-24 (SSCI-24) questionnaires. Potential determinants were evaluated with univariate statistical analyses for their contribution to total, internalized (inner-self derived) and externalized (society derived) stigma. Important findings were further evaluated on hierarchical regression models. RESULTS: Disability levels were found to be the most powerful predictor in all stigma categories, followed by the presence of mental illness. Working and caregiving status were also ascertained as determinants of internalized stigma. Stigma levels displayed strong negative correlation with all composites of MSQoL-54. CONCLUSIONS: Stigma is present in the social environment of MS patients and was confirmed as a barrier (according to the International Classification of Functioning, Disability and Health), with detrimental effects on their QoL levels and functioning performances. Disability and mental illness were shown as the principal determinants of stigma, while financial characteristics were not as equally involved. Further validation of these results in other MS populations may provide safer conclusions, towards more efficacious patient-centered care outcomes.

Preoperative neuropsychological presentation of patients with refractory frontal lobe epilepsy.

BACKGROUND: This study investigated whether certain cognitive deficits are associated with frontal lobe epilepsy (FLE) aiming to contribute with localization data to the preoperative assessment of epilepsy surgery candidates. METHODS: We evaluated 34 patients with refractory FLE, 37 patients with refractory medial temporal lobe epilepsy (MTLE), and 22 healthy individuals in attention, psychomotor speed, motor function, verbal memory span, verbal fluency, response inhibition/interference, concept formation and set shifting, anticipation and planning, global memory. RESULTS: Neuropsychological performances of FLE and MTLE were similar, with the only exception the WCST-number of categories index, measuring mental flexibility, in which MTLE patients performed significantly worse than FLE patients. Left-FLE patients presented more perseverative responding compared to both other patient groups and healthy controls (HCs), while left-MTLE patients showed worse sorting abilities than the other epilepsy groups. CONCLUSIONS: Our findings suggest a weak cognitive differentiation between FLE and MTLE, probably attributed to the intricate nature of fronto-temporal connectivity frequently resulting in overlapping deficits as well as the confounding effects of seizure-related variables. In clinical practice, a highly individualized (idiographic) neuropsychological approach along with the inclusion of concurrent EEG recordings (e.g., interictal coupling) may be of help for neuropsychologists in identifying FLE patients from those with medial temporal pathology presenting frontal dysfunction as a secondary cognitive symptom.

Frontotemporal Dysfunction in Amyotrophic Lateral Sclerosis: A Discriminant Function Analysis.

BACKGROUND: There is growing evidence for extramotor dysfunction (EMd) in amyotrophic lateral sclerosis (ALS), with a reported prevalence of up to 52%. OBJECTIVE: In the present study, we explore the clinical utility of a brief neuropsychological battery for the investigation of cognitive, behavioral, and language deficits in patients with ALS. METHODS: Thirty-four consecutive ALS patients aged 44-89 years were tested with a brief neuropsychological battery, including executive, behavioral, and language measures. Patients were initially classified as EMd or non-EMd based on their scores on the frontal assessment battery (FAB). RESULTS: Between-group comparisons revealed significant differences in all measures (p < 0.01). Discriminant analysis resulted in a single canonical function, with all tests serving as significant predictors. This function agreed with the FAB in 13 of 17 patients screened as EMd and identified extramotor deficits in 2 additional patients. Overall sensitivity and specificity estimates against FAB were 88.2%. CONCLUSIONS: We stress the importance of discriminant function analysis in clinical neuropsychological assessment and argue that the proposed neuropsychological battery may be of clinical value, especially when the option of extensive and comprehensive neuropsychological testing is limited. The psychometric validity of an ALS-frontotemporal dementia diagnosis using neuropsychological tests is also discussed.

Clinical and cognitive implications of cerebrospinal fluid oligoclonal bands in multiple sclerosis patients.

The presence of cerebrospinal fluid oligoclonal bands (CSF-OCB) in Caucasian patients with multiple sclerosis (MS) is supportive of diagnosis, though the relation with patients' clinical and specifically cognitive features has never been established or thoroughly examined. Thus, we investigated the clinical and for the first time the cognitive profile of MS patients in relation to CSF-OCB. We studied 108 patients with and without OCB and recorded demographic characteristics and detailed clinical data. A comprehensive neuropsychological battery covering different cognitive domains (attention/processing speed, memory, perception/constructions, reasoning, executive functions) was administered to MS patients and 142 demographically related healthy controls (HC). We did not find any significant differences between patients with and without OCB on demographic and clinical parameters (p > 0.05), including subtype and brain neuroimaging findings. Results revealed significantly higher cognitive scores in HC compared to both OCB subgroups, with more widespread cognitive changes in patients with OCB. Analysis between OCB subgroups showed significantly worse performance in patients with OCB on visual memory (Rey's complex figure test-recall; p = 0.006). Concluding, the presence of CSF-OCB in our MS patients tends to be related to more widespread cognitive changes, specifically worse visual memory. Future longitudinal studies in different populations are warranted to better clarify the clinical and cognitive characteristics related to CSF-OCB which could serve as early biomarker in disease monitoring.

Neurocognitive impairment in Whipple disease with central nervous system involvement.

Young-onset dementias pose a major challenge to both clinicians and researchers. Cognitive decline may be accompanied by systemic features, leading to a diagnosis of "dementia plus" syndromes. Whipple disease is a rare systemic illness characterized by arthralgias, chronic diarrhea, weight loss, fever, and abdominal pain. Central nervous system involvement, including severe cognitive deterioration, may precede systemic manifestations, appear during the course of the disease, or even be the only symptom. We report a previously highly functional 48-year-old man whom we first suspected of having early-onset neurodegenerative dementia but then diagnosed with Whipple disease based on a detailed clinical and laboratory evaluation. Initial neuropsychological evaluation revealed marked impairment in the patient's fluid intelligence and severe cognitive deficits in his information processing speed, complex attention, memory, visuomotor and construction dexterities, problem solving, and executive functions. At neuropsychological follow-up 21 months later, his information processing speed had improved only slightly and deficits persisted in his other cognitive functions. Repeat brain magnetic resonance imaging at that time showed that he had responded to antibiotic treatment. Because Whipple disease can cause young-onset "dementia plus" syndromes that may leave patients with neurocognitive deficits even after apparently successful treatment, we recommend comprehensive neuropsychological assessment for early detection of residual and reversible cognitive processes and evaluation of treatment response.

Auditory event-related potentials (P300) and mesial temporal sclerosis in temporal lobe epilepsy patients.

AIMS: To investigate the role of centrally recorded P300 in patients suffering from mesial temporal sclerosis-temporal lobe epilepsy (MTS-TLE). METHODS: Sixteen patients (3 men and 13 women; median age: 32.5 years old) suffering from TLE with MTS and 43 healthy controls (12 men and 31 women; median age: 35 years old) participated in the study. P300 was elicited using an auditory two-stimulus oddball paradigm. In order to address the aim of the study, we adopted two statistical approaches; hierarchical linear regression analyses and ROC curves. RESULTS: After adjusting for age, MTS patients had a mean reduction of P300 amplitude by 6.93 µV and a mean increase of P300 latency by 38.78 ms, compared to controls. Age and MTS-TLE status accounted for 32 and 16% of the variance of latency and amplitude, respectively. Diagnostic analyses to detect MTS-TLE status revealed a sensitivity and specificity of 88 and 65% for amplitude and 81 and 70% for latency, respectively. No association between duration of disease and P300 characteristics were found. CONCLUSIONS: This study, along with other studies, contributes to our understanding and clinical significance of centrally recorded P300s in MTS-TLE patients. Future studies should focus on the association of these P300s with cognition in such patients.

Trail Making Test error analysis in classic motor neuron disease.

The use of non-traditional scores in neuropsychological assessment allows for pattern analysis of test performance, commonly referred to as Quantified Process Approach (QPA). In the present study, the QPA was taken to study error rates on the Trail Making Test (TMT) in 26 non-demented patients with classic motor neuron disease (cMND), who commonly present with impaired cognitive flexibility, and 26 matched healthy controls. Between-group comparisons revealed that cMND patients exhibited higher total error rates on the TMT Part B (TMT-B) relative to controls (p < 0.001), though no significant associations were noted between TMT errors and measures of attention and executive function obtained using the Stroop Neuropsychological Screening Test, the Wechsler Adult Intelligence Scale Digit Symbol and Digit Span subtests and the Wisconsin Card Sorting Test. Moreover, the percentage of cMND patients with normal TMT-B time-to-completion who committed at least one error (either sequential or perseverative errors) in TMT-B was significantly higher compared to controls (p = 0.005). These findings suggest that error analysis using the QPA may increase the clinical utility of TMT and should be considered in addition to time-to-completion scores, in the neuropsychological assessment of patients with cMND.

Simulating memory outcome before right selective amygdalohippocampectomy.

In this paper we present the case of a left-sided speech dominant patient with right medial temporal sclerosis (RMTS) and pharmacoresistant epilepsy who showed improved verbal memory during intracarotid amobarbital test (IAT) at his right hemisphere as compared with his own performance before the drug injection (baseline), as well as after right selective amygdalohippocampectomy. We suggest that the defective verbal memory shown by this patient is due to abnormal activity of his right hippocampus that interfered with the function of his left hippocampus. This hypothesis was demonstrated by the fact that disconnection of the two hippocampi, either by anesthetisation or by resection of the right hippocampus, disengaged the left hippocampus and, consequently improved its function. This paper main objective is twofold: first to contribute to the field of neuropsychology of epilepsy surgery by emphasising on postoperative memory outcomes in right medial temporal lobe epilepsy (RMTLE) patients, particularly those undergoing amygdalohippocampectomy, as the pattern of memory changes after resection of the right temporal lobe is less clear; second, by focusing on memory performance asymmetries during IAT, and comparatively considering them with neuropsychological memory performance, because of their possible prognostic-simulating value.

[The effects of carotid revascularization on mood symptoms and quality of life in patients with high - grade carotid stenosis].

Carotid occlusive disease has been related to ischaemic strokes and cerebral hypoperfusion, thus affecting patients' quality of life, mainly because of cognitive decline and depressive symptoms. Carotid revascularization techniques [carotid endarterectomy (CEA) and carotid artery stenting (CAS)] may, postoperatively, have a positive impact on patients' quality of life and mental condition, though there have been also presented elusive findings and controversial results. The aim of the present study is to evaluate the effect of carotid revascularization (CEA, CAS) on patients' psychological condition and quality of life through a baseline and follow-up examination. We present data of a group of 35 patients (age range:60-80 years, ΜA=70,26-SD=9,05) with severe, left or right, carotid artery stenosis (>75%), presented with or without symptoms, who underwent surgical treatment with CEA or CAS. Baseline and follow-up (6 months post-surgery) evaluation was conducted in order to assess patients' depressive symptoms and quality of life, through completion of the Beck Depression Inventory and WHOQOL-BREF Inventory, respectively. No statistically significant (p < 0,05) effect of the revascularization process on mood or quality of life assessment could be documented for our patients, regardless of the applied technique (CAS or CEA). Our study supports existing evidence that all of the traditional vascular risk factors represent active participants in the inflammatory process, which has also been implicated in the pathophysiology of depression as well as in pathogenesis of atherosclerotic processes. Thus we have to illuminate new links between the two nosological entities, in the crossroads of psychiatry, neurology and angiology, through the pathways of inflammatory reactions and endothelium dysfunctions. Even though the effects of carotid revascularization on patient's mood and quality of life, are often characterized by opposing results, pathophysiological processes of "vascular depression" and "post stroke depression" remain a promising interdisciplinary medical domain, sharing both scientific and clinical interests between the fields of neurosciences and vascular medicine. Our results, regarding the bilateral connection of depression and carotid artery disease, advocate a most probable causality link between atherosclerotic process and depressive symptoms, rather than justifying a direct association between depressive disorders and carotid stenosis and inferred cerebral blood flow reduction per se.

Arousal deregulation in the co-shaping of neuropsychological dysfunction in frontal and mesial temporal lobe epilepsy.

OBJECTIVE: Our work aims to investigate the role of physiological arousal in the expression of neuropsychological deficits in frontal lobe epilepsy (FLE) and mesial temporal lobe epilepsy (mTLE), by drawing on the Lurian theory of brain function. METHODS: For this study a total of 43 patients with focal onset epilepsy has been taken; twenty-four patients with FLE, 19 patients with mTLE and 26 healthy controls, all matched for age and education. Participants underwent a comprehensive neuropsychological assessment including various cognitive domains, such as attention, episodic memory, speed of information processing, response inhibition and mental flexibility, working memory, verbal fluency (phonological & semantic). RESULTS: There were no significant differences between FLE and mTLE patients in terms of neuropsychological performance. However, both FLE and mTLE patients showed significantly worse performance in several cognitive domains than HCs. The results seem to support our hypothesis that aberrant physiological arousal, as reflected in patients' worse performance in vigilance and attention, response inhibition, and processing speed, along with other disease-specific variables, may co-determine neuropsychological dysfunction and/or impairment in both FLE and mTLE. CONCLUSION: Identifying a differential arousal-related neuropsychological affection in FLE and mTLE, among the known deleterious effects of the functional deficit zone and other disease-related variables, may further our understanding of the underlying cognitive-pathophysiological mechanisms in focal epilepsy syndromes.

Selective attention and the three-process memory model for the interpretation of verbal free recall in amyotrophic lateral sclerosis.

The present study investigates selective attention and verbal free recall in amyotrophic lateral sclerosis (ALS) and examines the contribution of selective attention, encoding, consolidation, and retrieval memory processes to patients' verbal free recall. We examined 22 non-demented patients with sporadic ALS and 22 demographically related controls using Stroop Neuropsychological Screening Test (SNST; selective attention) and Rey Auditory Verbal Learning Test (RAVLT; immediate & delayed verbal free recall). The item-specific deficit approach (ISDA) was applied to RAVLT to evaluate encoding, consolidation, and retrieval difficulties. ALS patients performed worse than controls on SNST (p < .001) and RAVLT immediate and delayed recall (p < .001) and showed deficient encoding (p = .001) and consolidation (p = .002) but not retrieval (p = .405). Hierarchical regression analysis revealed that SNST and ISDA indices accounted for: (a) 91.1% of the variance in RAVLT immediate recall, with encoding (p = .016), consolidation (p < .001), and retrieval (p = .032) significantly contributing to the overall model and the SNST alone accounting for 41.6%; and (b) 85.2% of the variance in RAVLT delayed recall, with consolidation (p < .001) and retrieval (p = .008) significantly contributing to the overall model and the SNST alone accounting for 39.8%. Thus, selective attention, encoding, and consolidation, and to a lesser extent of retrieval, influenced both immediate and delayed verbal free recall. Concluding, selective attention and the memory processes of encoding, consolidation, and retrieval should be considered while interpreting patients' impaired free recall. (JINS, 2012, 18, 1-10).

The role of working memory and information processing speed on wisconsin card sorting test performance in Parkinson disease without dementia.

INTRODUCTION: Wisconsin Card Sorting Test (WCST) performance is often compromised in Parkinson disease (PD). OBJECTIVE: We aimed to investigate (a) the role of working memory (WM) and information processing speed (IPS) in the WCST performance of PD without dementia and (b) the profile of PD without dementia optimal WCST performance. METHODS: 73 nondemented patients with PD were examined in WCST, WM (Digit Span Backwards [DSPANB] and Arithmetic subscale, Wechsler Adult Intelligence Scale [WAIS]), and IPS (Digit Symbol subscale-WAIS and Trail Making Test, part A [TMT-A]) and compared to a group of 48 healthy participants. The group with PD was further divided into 2 subgroups on the basis of their WCST performance, number of categories achieved (CAT):0-2 and CAT:3-6, and comparisons were performed. RESULTS: The DSPANB correlated significantly and was the only neuropsychological variable that significantly contributed to the WCST perseverative errors (WPERRORS) performed by the PD group. Differences in the cognitive performance between CAT:3-6 and CAT:0-2 PD subgroups were no longer significant after controlling for age and general level of intelligence (full IQ [FIQ]). Age and FIQ significantly contributed to the WPERRORS performed by CAT:3-6 PD subgroup, while DSPANB was the only variable that significantly contributed to their WCST overall performance. CONCLUSIONS: Our findings address the relationship between WM and inflexible behavior exhibited by PD without dementia, argue for the importance of lower age, higher education, and level of intelligence for the successful performance on WCST; yet, the differences in cognitive performance regardless of the duration of illness within our patients with PD provide support to cognitive reserve concept.

The severity of executive dysfunction among different PD-MCI subtypes.

Aim to examine the severity of executive dysfunction among different Parkinson's disease (PD)-mild cognitive impairment (MCI) subtypes in the early stages of the disease. The final sample consisted of 65 patients with mild PD progression. Based on neuropsychological measures, our sample was categorized into three PD-MCI subtypes: (1) PD-MCI executive group (n = 24), (2) PD-MCI executive plus memory group (n = 22), and (3) PD-MCI executive plus visuospatial group (n = 19). Patients' executive functions were evaluated with the Trail Making Test-Part B (TMT-B) and Stroop Neuropsychological Screening Test (SNST) for mental flexibility and inhibitory control, respectively. One-way ANOVA results indicated significant differences among the three subgroups on TMT-B and SNST performance. Post hoc Tukey honestly significant different (HSD) tests revealed that the PD-MCI executive plus visuospatial group had lower performances on both executive measures than the other two groups. Contrastingly, no significant differences were observed between the PD-MCI executive group and PD-MCI executive plus memory group. Our results indicated that the severity of executive dysfunction varies across different PD-MCI subtypes. These findings are discussed within the framework of the dual syndrome hypothesis and highlight the utility of determination of executive impairment severity for effective clinical management of patients with PD.

Specific disruption of the ventral anterior temporo-frontal network reveals key implications for language comprehension and cognition.

Recent investigations have raised the question of the role of the anterior lateral temporal cortex in language processing (ventral language network). Here we present the language and overall cognitive performance of a rare male patient with chronic middle cerebral artery cerebrovascular accident with a well-documented lesion restricted to the anterior temporal cortex and its connections via the extreme capsule with the pars triangularis of the inferior frontal gyrus (i.e. Broca's region). The performance of this unique patient is compared with that of two chronic middle cerebral artery cerebrovascular accident male patients with damage to the classic dorsal posterior temporo-parietal language system. Diffusion tensor imaging is used to reconstruct the relevant white matter tracts of the three patients, which are also compared with those of 10 healthy individuals. The patient with the anterior temporo-frontal lesion presents with flawless and fluent speech, but selective impairment in accessing lexico-semantic information, in sharp contrast to the impairments in speech, sentence comprehension and repetition observed after lesions to the classic dorsal language system. The present results underline the contribution of the ventral language stream in lexico-semantic processing and higher cognitive functions, such as active selective controlled retrieval.