Spinal cord stimulation may improve gait and cognition in hereditary spastic paraplegia with mental retardation: a case report.

BACKGROUND: Hereditary spastic paraplegia (HSP) include various sporadic and hereditary neurodegenerative disorders, characterized by progressive spasticity and weakness of lower limbs, possibly associated to additional features. CASE PRESENTATION: We report a male HPS patient in his 40 s, showing mental retardation associated with language impairment, dysarthria, and increased urinary frequency. Three months after treatment with electric chronic high-frequency cervical spinal cord stimulation (HF-SCS), he showed an amelioration of motor symptoms (lower limbs spasticity and gait), dysarthria, cognitive functioning (language and constructive praxic abilities), and urinary symptoms (decreased urinary frequency). Single-photon emission computed tomography (SPECT) showed a postoperative increase of cerebral perfusion in right frontal cortex and temporal cortex bilaterally. CONCLUSION: In our patient, HF-SCS might have induced an activation of ascending neural pathways, resulting in changes in activity in various cortical areas (including sensory-motor cortical areas), which may give rise to a modulation of activity in spared descending motor pathways and in neural networks involved in cognitive functions, including language. Although further studies in patients with HPS are needed to clarify whether HF-SCS can be a suitable treatment option in HSP, our observation suggests that HF-SCS, a minimally invasive neurosurgical procedure, might induce beneficial effects of on various symptoms of such orphan disease.

Naming famous people through face and voice: a normative study.

OBJECTIVES: Within the large topic of naming disorders, an important and separated chapter belongs to proper names. Defects of proper naming could be a selective linguistic problem. Sometimes, it includes names belonging to various kinds of semantically unique entities, but other times, it has been observed for famous people proper names only. According to Bruce and Young's model, different stages allow to recognize, identify, and name famous people from their faces and voices, subsuming different anatomical pathways, both in right temporal lobe, and their different efficiency in this task. The present study aimed to report the normative data concerning the naming of the same famous people from voice and face. SUBJECTS AND METHODS: One hundred fifty-three normal subjects underwent a test in which they were requested to name famous people from their face and from their voice. The stimuli belonged to the previously published Famous People Recognition Battery. RESULTS: The mean percentage score on naming from face was 84.42 ± 12.03% (range 55.26-100%) and the mean percentage score on naming from voice was 66.04 ± 16.81% (range 28.13-100%). The difference observed in performance by face and by voice resulted significant (t|153 = 15.973; p < 0.001). Regression analyses showed that the percentage score obtained on naming from faces was predicted by education, whereas naming from voice was predicted by education and gender. DISCUSSION: Naming from voice is more difficult than from face, confirming a different difficulty of the two tasks. Education showed high predicting value for faces and less for voices, whereas gender contributed to predict results only for voices.

Famous people recognition through personal name: a normative study.

In this normative study, we investigated famous people recognition through personal name, using as stimuli the names of the same 40 Italian famous persons whose faces and voices had been utilized for the normative study of the Famous People Recognition Battery. For each famous people, we assessed name familiarity, person identification (when the name had been considered as familiar), and false alarms. The investigation was carried out on 143 normal subjects who varied in age and education. Name familiarity and semantic scores were affected by educational level, whereas age influenced false alarms. A comparison between results obtained with names in this research and with faces and voices of the same famous people in our previous study showed that familiarity scores were higher for personal names than those for faces and voices, which obtained the worst scores. Person identification scores were not significantly different from names and from faces, but both these scores were significantly higher than the semantic scores obtained by voices. Taken together, these results are inconsistent with the influential interactive activation and competition model of person recognition.

Recognition disorders for famous faces and voices: a review of the literature and normative data of a new test battery.

Several anatomo-clinical investigations have shown that familiar face recognition disorders not due to high level perceptual defects are often observed in patients with lesions of the right anterior temporal lobe (ATL). The meaning of these findings is, however, controversial, because some authors claim that these patients show pure instances of modality-specific 'associative prosopagnosia', whereas other authors maintain that in these patients voice recognition is also impaired and that these patients have a 'multimodal person recognition disorder'. To solve the problem of the nature of famous faces recognition disorders in patients affected by right ATL lesions, it is therefore very important to verify with formal tests if these patients are or are not able to recognize others by voice, but a direct comparison between the two modalities is hindered by the fact that voice recognition is more difficult than face recognition. To circumvent this difficulty, we constructed a test battery in which subjects were requested to recognize the same persons (well-known at the national level) through their faces and voices, evaluating familiarity and identification processes. The present paper describes the 'Famous People Recognition Battery' and reports the normative data necessary to clarify the nature of person recognition disorders observed in patients affected by right ATL lesions.

Cognitive and behavioral determinants of psychotic symptoms in Alzheimer's disease.

AIMS: To investigate the relationship between psychotic symptoms and cognitive impairment in Alzheimer's disease (AD). METHODS: A total of 108 subjects affected by AD were subdivided into subjects without delusions (ND), subjects with paranoid delusions (PD), subjects with delusional misidentifications (DM), subjects with both DM and PD (DM+PD), subjects with visual hallucinations (v-HALL), and subjects without visual hallucinations (N-HALL). RESULTS: PD and ND subjects performed similarly on neuropsychological tests, while DM patients performed significantly worse than PD and ND patients. v-HALL patients performed worse than N-HALL patients on memory, visuospatial, and executive functions. As for behavioral features, DM and v-HALL subjects reported higher scores on the abnormal motor behavior subscale of the neuropsychiatric inventory (NPI); PD subjects reported higher scores on the disinhibition subscale of the NPI. The severity of PD was predicted by the severity of disinhibition (B = 0.514; p = 0.016) but not by neuropsychological performances. The severity of DM was predicted by age (B = 0.099; p = 0.048) and MMSE (B = -0.233; p = 0.001). The severity of v-HALL was predicted by age (B = 0.052; p = 0.037) and scores on an immediate visual memory task (B = -0.135; p = 0.007). CONCLUSIONS: The occurrence of PD may require the relative sparing of cognitive functions and be favored by frontal lobe dysfunction, while DM is associated with the overall level of cognitive impairment. Finally, v-HALL are associated with the impairment of visuospatial abilities.

Which components of famous people recognition are lateralized? A study of face, voice and name recognition disorders in patients with neoplastic or degenerative damage of the right or left anterior temporal lobes.

We administered to large groups of patients with neoplastic or degenerative damage affecting the right or left ATL, the 'Famous People Recognition Battery' (FPRB), in which subjects are required to recognize the same 40 famous people through their faces, voices and names, to clarify which components of famous people recognition are lateralized. At the familiarity level, we found, as expected, a dissociation between a greater impairment of patients with right ATL lesions on the non-verbal (face and voice) recognition modalities and of those with left ATL lesions on name familiarity. Equally expected were results obtained at the naming level, because the worse naming scores for faces and voices were observed in left-sided patients. Less foregone were, for two reasons, results obtained at the semantic level. First, no difference was found between the two hemispheric groups when scores obtained on the verbal (name) and non-verbal (face and voice) recognition modalities were account for. Second, the face and voice recognition modalities showed a different degree of right lateralization. All groups of patients showed, indeed, both at the familiarity and at the semantic level, a greater difficulty in the recognition of voices regarding faces, but this difference reached significance only in patients with right ATL lesions, suggesting a greater right lateralization of the more complex task of voice recognition. A model aiming to explain the greater right lateralization of the more perceptually demanding voice modality of person recognition is proposed.

Selective impairment of living things and musical instruments on a verbal 'Semantic Knowledge Questionnaire' in a case of apperceptive visual agnosia.

Semantic memory was investigated in a patient (MR) affected by a severe apperceptive visual agnosia, due to an ischemic cerebral lesion, bilaterally affecting the infero-mesial parts of the temporo-occipital cortices. The study was made by means of a Semantic Knowledge Questionnaire (Laiacona, Barbarotto, Trivelli, & Capitani, 1993), which takes separately into account four categories of living beings (animals, fruits, vegetables and body parts) and of artefacts (furniture, tools, vehicles and musical instruments), does not require a visual analysis and allows to distinguish errors concerning super-ordinate categorization, perceptual features and functional/encyclopedic knowledge. When the total number of errors obtained on all the categories of living and non-living beings was considered, a non-significant trend toward a higher number of errors in living stimuli was observed. This difference, however, became significant when body parts and musical instruments were excluded from the analysis. Furthermore, the number of errors obtained on the musical instruments was similar to that obtained on the living categories of animals, fruits and vegetables and significantly higher of that obtained in the other artefact categories. This difference was still significant when familiarity, frequency of use and prototypicality of each stimulus entered into a logistic regression analysis. On the other hand, a separate analysis of errors obtained on questions exploring super-ordinate categorization, perceptual features and functional/encyclopedic attributes showed that the differences between living and non-living stimuli and between musical instruments and other artefact categories were mainly due to errors obtained on questions exploring perceptual features. All these data are at variance with the 'domains of knowledge' hypothesis', which assumes that the breakdown of different categories of living and non-living things respects the distinction between biological entities and artefacts and support the models assuming that 'category-specific semantic disorders' are the by-product of the differential weighting that visual-perceptual and functional (or action-related) attributes have in the construction of different biological and artefacts categories.

The Destiny of Multiple Domain Amnesic Mild Cognitive Impairment: Effect of Alternative Neuropsychological Definitions and Their Adjunctive Role in Respect of Memory Impairment.

OBJECTIVE: Mild cognitive impairment is the main risk factor of dementia. Previous evidence has claimed that subjects with memory disturbances associated with impairment of other cognitive domains (multiple domain amnesic MCI) are at the highest risk of developing dementia. To date, a shared definition of amnesic MCI multiple domain (aMCI-MD) is still lacking. METHOD: 163 subjects with aMCI were enrolled and followed-up for 2 years. They underwent a baseline comprehensive neuropsychological battery. The cut-off point for each test was set at 1, 1.5, and 2 SD below the mean obtained in normative studies; aMCI-MD was defined as the occurrence of abnormal scores on at least one, two, or three tests not assessing memory. The Episodic Memory Score (EMS), that measures the severity of memory impairment, was determined. Logistic regressionand Cox's proportional hazard risk models were carried out. The adjunctive effect of the definitions of aMCI-MD on the severity of memory impairment was assessed. RESULTS: Fifty-four subjects progressed to dementia. Only restrictive definitions of aMCI-MD (at least three tests below 1.5 SD; at least two tests below 2 SD) predicted conversion to dementia in both logistic regression and survival analysis. None of the conditions showed a significant adjunctive effect on the EMS. CONCLUSIONS: The predictive effect of impairment in tests assessing cognitive domains other than memory depends on its psychometric definition. The use of a restrictive definition would be of some usefulness, but the adjunctive effect of such a definition on an integrated analysis of memory impairment may be questionable.

Semantic Memory as an Early Cognitive Marker of Alzheimer's Disease: Role of Category and Phonological Verbal Fluency Tasks.

BACKGROUND: The assessment of semantic memory may be a useful marker to identify individuals with mild cognitive impairment (MCI) who will progress to Alzheimer's disease (AD) in the early stages of the disease. OBJECTIVE: The aim of this five-year follow-up longitudinal study is to assess whether semantic assessment could predict progression in MCI. METHODS: A population of MCI (N = 251); mild (N = 178) and moderate AD (N = 114); and a sample of healthy participants (HP; N = 262) was investigated. The five-year follow-up of the MCI group was completed by 178 patients. Semantic and episodic memory measures were used, including a measure of the discrepancy between categorical and phonological verbal fluency, the semantic-phonological delta (SPD). The main outcome was the progression of MCI due to AD to dementia. RESULTS: A general linear model showed a significant effect of diagnosis on SPD (Wilks' Lambda = 0.591; p < 0.001). The estimated marginal means were -0.91 (SE = 0.185) in HP, -1.83 (SE = 0.187) in MCI, -1.16 (SE = 0.218) in mild AD, and -1.02 (SE = 0.275) in moderate AD. Post-hoc comparisons showed a significant difference between MCI and HP (p < 0.001). The follow-up was completed by 178 MCI individuals. SPD in MCI patients who progress to dementia was significantly lower than in MCI that will not progress (p = 0.003). Together with the Mini-Mental State Examination, the SPD was the only measure with a significant predicting effect at the five-years follow-up (p = 0.016). CONCLUSION: The SPD indicates the impairment of semantic memory in individuals with underlying AD at the MCI early stage, reflecting the early involvement of perirhinal and entorhinal cortices in the earliest stages of AD neuropathological process.

Semantic Relations in a Categorical Verbal Fluency Test: An Exploratory Investigation in Mild Cognitive Impairment.

Categorical verbal fluency tests (CFT) are commonly used to assess the integrity of semantic memory in individuals with brain damage. Persons with Dementia of the Alzheimer's Type display a reduced output on CFT, and a similar pattern has been reported in persons with amnesic Mild Cognitive Impairment (aMCI). The aims of the present study were to assess whether the semantic relations between lexical entries produced on a categorical fluency test were different between healthy persons and those with aMCI, and whether this difference was more pronounced in individuals who converted to dementia during a 3-year follow-up period. METHODS: We recruited 34 individuals with aMCI and 29 matched healthy persons. During the follow-up period, 10 individuals converted to Dementia (aMCI-conv). Two measures assessing semantic relations between consecutively produced word pairs (Path length and Extended Gloss Overlap) were obtained from the Wordnet database. RESULTS: The number of word pairs analyzed among the healthy participants (HP) and persons with aMCI were 498 (birds: 262; pieces of furniture: 236) and 395 (birds: 174; pieces of furniture: 221), respectively. Path length was lower in aMCI-conv than in HP (p = 0.035), but no differences were found between stable aMCI and HP, and between aMCI-stable and aMCI-conv. The ANOVA for lexical entries belonging to the "birds" category showed a significant effect of group (F = 5.630; p = 0.004); the post hoc analysis showed a significant difference between HP and aMCI-conv (p = 0.003). The "pieces of furniture" category was significantly affected by group (F = 4.107; p = 0.017); the post hoc test showed significant differences between aMCI-conv and healthy individuals (p = 0.049), and between aMCI-conv and stable aMCI (p = 0.001). DISCUSSION: Individuals with aMCI who convert to dementia show a deterioration in the semantic relations between lexical entries, produced on a CFT. This phenomenon may be interpreted as a marker of a very early disruption of semantic memory.

Role of CLU, PICALM, and TNK1 Genotypes in Aging With and Without Alzheimer's Disease.

Healthy and impaired cognitive aging may be associated to different prevalences of single-nucleotide polymorphisms (SNPs). In a multicenter case-control association study, we studied the SNPs rs11136000 (clusterin, CLU), rs541458 (phosphatidylinositol binding clatrin assembly protein, PICALM), and rs1554948 (transcription factor A, and tyrosine kinase, non-receptor, 1, TNK1) according to the three age groups 50-65 years (group 1), 66-80 years (group 2), and 80+ years (group 3) in 569 older subjects without cognitive impairment (NoCI) and 520 Alzheimer's disease (AD) patients. In NoCI subjects, a regression analysis suggested a relationship between age and TNK1 genotypes, with the TNK1-A/A genotype frequency that increased with higher age, and resulting in a different distribution of the TNK1-A allele. In AD patients, a regression analysis suggested a relationship between age and PICALM genotypes and TNK1 genotypes, with the PICALM-T/C and TNK1-A/A genotype frequencies that decreased with increasing age. A resulting difference in the distribution of PICALM-C allele and TNK1-A allele was also observed. The TNK1-A allele was overrepresented in NoCI subjects than in AD patients in age groups 2 and 3. These results confirmed after adjustment for apolipoprotein E polymorphism, which suggested a different role of PICALM and TNK1 in healthy and impaired cognitive aging. More studies, however, are needed to confirm the observed associations.

Standardization, Clinical Validation, and Typicality Norms of a New Test Assessing Semantic Verbal Fluency.

OBJECTIVE: Semantic verbal fluency (SVF) tests are widely used in clinical neuropsychology. We propose the standardization and clinical validation of a new SVF test based on the production of names of birds and articles of furniture (Birds and Articles of Furniture test-BAF). METHODS: A sample of 268 subjects aged 40 years or more underwent the test. The clinical validation was conducted on subjects affected by amnesic Mild Cognitive Impairment (aMCI; N = 106), mild (N = 178), and moderate (N = 114) Alzheimer's disease (AD). RESULTS: The BAF total score was influenced by both age and education, whereas the single scores obtained on BAF were also influenced by gender. The percentage of subjects with pathological score on BAF increased from aMCI (19%) to mild (45.5%) and moderate (71.1%) AD, and receiver operating characteristic curves analysis showed that the BAF may be highly reliable in distinguishing aMCI and AD patients from healthy subjects. We also provide typicality norms for birds and articles of furniture that could be useful in the assessment of qualitative features of words produced in semantic fluency tests. CONCLUSIONS: The BAF test could be a valid and reliable tool in both clinical practice and research on subjects affected by cognitive impairment.

Are Raw Scores on Memory Tests Better than Age- and Education- Adjusted Scores for Predicting Progression from Amnesic Mild Cognitive Impairment to Alzheimer Disease ?

In this prospective longitudinal study, conducted in a large sample of amnestic MCI patients over a three-year period, we investigated the recently advanced proposal that unadjusted test scores obtained at baseline on long-term memory tests are more reliable than age- and education-corrected scores in predicting progression from aMCI to AD. Our experimental sample consisted of 270 aMCI patients who underwent extensive neurological and neuropsychological examinations both at baseline and at the follow-up, conducted at least 3 years later. At the follow-up 80 patients had converted to overt dementia. The predictive capacity of raw, age-corrected, education-corrected and fully corrected scores on RAVLT immediate and delayed recall was compared by examining the area under the ROC curves (AUCs) of all of these scores to assess which (raw or corrected) scores achieves the better reliability in predicting conversion to dementia. The condition (aMCI stable vs converted) was analyzed to assess the odds ratios resulting from a logistic regression on the corrected and uncorrected scores of RAVLT immediate and delayed recall. Even if both in immediate and in delayed recall the ROCs of 'raw scores' were generally higher than the other ROCs on corrected scores, these differences did not reach the level of statistical significance, failing to support the claim that unadjusted test scores are superior to age- and education-corrected scores in predicting progression from aMCI to AD.

Usefulness of an Integrated Analysis of Different Memory Tasks to Predict the Progression from Mild Cognitive Impairment to Alzheimer's Disease: The Episodic Memory Score (EMS).

Taking into the account both the severity and the consistency of performances obtained on memory tests by patients with amnestic mild cognitive impairment (aMCI) could improve the power to predict their progression to Alzheimer's disease. For this purpose, we constructed the Episodic Memory Score (EMS), which is obtained by subdividing in tertiles performances obtained at baseline in verbal (RAVLT) and visual episodic memory (Rey-Osterrieth Figure-delayed recall) and giving a score ranging from 1 (worst result) to 3 (best result) to results falling within each tertile. The EMS was computed for each patient by summing the tertile score obtained on each memory task, so that the total score ranged from 4 (worst performance) to 12 (best performance). The aMCI sample consisted of 198 subjects who completed the two-year follow-up, at the end of which 55 subjects had converted to dementia. The mean EMS score obtained by aMCI converters was significantly lower than that of aMCI-stable patients. In detecting conversion to dementia, the comparison between EMS and individual memory scores obtained at baseline was made by computing ROC curves, and estimating the respective area under the curve (AUC). The EMS had a larger AUC than the individual memory scores. At baseline aMCI converters performed worse than non-converters not only on memory tasks, but also on executive functions tasks. However, in a multiple variables logistic regression analysis in which all scores showing statistically significant differences between aMCI-converters and aMCI-stable were entered, the EMS was the only reliable predictor of progression from aMCI to dementia.

Does semantic memory impairment in amnestic MCI with hippocampal atrophy conform to a distinctive pattern of progression?

Subjects with Mild Cognitive Impairment (MCI) are normally classified according to the presence of episodic memory deficits associated or not to disturbances of other cognitive domains. The present study had two aims: to identify discrete subtypes of amnestic MCI (a-MCI) with hippocampal atrophy; and to assess if the identified subtypes show different rates of progression to dementia. Sixty-seven a-MCI subjects were enrolled, all showing significant hippocampal atrophy on MRI. The subjects underwent at baseline and at follow-up a comprehensive neuropsychological examination, and were followed-up for five years to detect the conversion to dementia. An exploratory factor analysis on neuropsychological performances at baseline identified three main factors that were subsequently used to perform a k-means cluster analysis. Three cluster of a-MCI subjects were identified: "pure amnestic" (N=29), "multiple domain"(N=16), and "amnestic/semantic"(N=22). The successive discriminant functions were able to correctly classify 88% of the subjects. During the follow-up, 33 subjects converted to dementia (49.2%), 14 "pure amnestic" (48.3%), 11 "multiple domain" (68.5%) and 8 "amnestic/semantic" (36.4%; log-rank: p=0.016); median survival was respectively 36, 22, and 39 months. On Cox proportional hazard model, baseline MMSE (HR=0,709; p=0.006), education (HR=1,115; p=0.011) and belonging to the "multiple domain" subgroup (HR=2,706; p=0.013) were significantly associated to higher rate of conversion to dementia. Our findings confirm the tendency to worst outcome of subjects with multiple domain MCI, and show that the association of episodic and semantic memory deficits, without other cognitive disturbances, could identify a specific cognitive pattern associated to slower cognitive decline, as previously reported in Alzheimer's Disease.

Frontotemporal dementia, Parkinsonism and lower motor neuron involvement in a patient with C9ORF72 expansion.

It has been recently reported that a large proportion of patients with familial and sporadic amyotrophic lateral sclerosis (ALS) and/or frontotemporal dementia (FTD) carries the hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72. We describe a patient with a complex phenotype characterized by behavioural variant of FTD, Parkinsonism and ALS with predominant lower motor neuron involvement in which the C9ORF72 expansion was detected.

Selective impairment of action-verb naming and comprehension in progressive supranuclear palsy.

Some previous studies in brain-damaged patients suggested that neural systems in the left temporal lobe might be crucial in the production and comprehension of nouns, while analogous systems in posterior frontal cortical areas might be involved in the production and comprehension of verbs. We assessed performance on neuropsychological tasks of production and comprehension of nouns and action-verbs in 10 patients with progressive supranuclear palsy (PSP) and in 10 age-matched healthy controls. PSP patients also underwent measurements of regional cerebral blood flow by means of single photon emission computed tomography (SPECT), using 99mTc-Ethyl Cysteinate Dimer. In all PSP patients, SPECT showed a significant hypoperfusion in the inferior frontal gyrus (IFG). PSP patients performed significantly worse than controls on all lexical-semantic tasks, except for the auditory lexical decision task on nouns. Within PSP patients, however, a significantly lower performance was observed on action-verbs as compared to nouns on various lexical-semantic tasks (oral and written confrontation naming, auditory and visual single-word comprehension). Analysis of individual performance revealed heterogeneous patterns of neuropsychological impairment in different PSP patients. Despite some difficulty in drawing clear-cut conclusions about the locus of functional damage, we hypothesise that in most of our PSP patients such selective impairment in the production and in the comprehension of action-verbs could be due to semantic deficits affecting the conceptual category of actions. These findings are consistent with the hypothesis that in PSP a dysfunction of neural systems in posterior frontal cortical areas (mainly involving the IFG) critical for processing the conceptual category of actions might result in a selective impairment of production and comprehension of action-verbs.

Presentation and validation of the multiple sclerosis depression rating scale: a test specifically devised to investigate affective disorders in multiple sclerosis patients.

Accurate diagnosis of depression in patients affected by MS is important, as it may be a cause of reduced quality of life and increased suicide risk. We present a new scale, the Multiple Sclerosis Depression Rating Scale (MSDRS), and assess its diagnostic accuracy in comparison to the Beck Depression Inventory (BDI). A total of 94 MS participants were classified as non-depressed (N = 44) or affected by mood disorder associated to MS with depressive manifestations (MSD-MDDM; N = 37) or with a major depression-like episode (MSD-MDL; N = 13). Each participant underwent a psychiatric interview, MSDRS, and BDI; diagnostic accuracy was evaluated using area under the ROC curve (AROC). The diagnostic accuracy of MSDRS and BDI was comparable when diagnosing both MSD-MDDM and MSD-MDL (AROC respectively 0.8998 and 0.8659); the MSDRS showed higher accuracy for the diagnosis of MSD-MDL (AROC respectively 0.9278 and 0.8314; p = .038). The MSDRS may be a reliable tool for the diagnosis of depression in MS.

Unilateral extradural motor cortex stimulation is safe and improves Parkinson disease at 1 year.

BACKGROUND: The primary motor cortex, which is part of the corticobasal ganglia loops, may be an alternative option for the surgical treatment of Parkinson disease. OBJECTIVE: To report on the 1-year safety and efficacy of unilateral extradural motor cortex stimulation in Parkinson disease. METHODS: A quadripolar electrode strip was extradurally implanted over the motor cortex. Stimulation was continuously delivered through the electrode paddle contralateral to the most affected clinical side. Subjects were prospectively evaluated by the Unified Parkinson's Disease Rating Scale (UPDRS) and the Parkinson's Disease Quality of Life Questionnaire. In addition, an extensive cognitive and behavioral assessment and electroencephalogram recording were performed. RESULTS: Nine patients were included in this study. No surgical complications or adverse events occurred. Moreover, no cognitive or behavioral changes were observed. Under the off-medication condition, the UPDRS III at baseline was decreased by 14.1%, 23.3%, 19.9%, and 13.2%, at 1, 3, 6, and 12 months, respectively. The motor effects were bilateral, appeared after 3 to 4 weeks of stimulation, and outlasted the stimulation itself for 3 to 4 weeks in 1 case of stimulator accidental switching off. The UPDRS IV was decreased by 40.8%, 42.1%, and 35.5% at 1, 3, and 12 months, respectively. The scores on the Parkinson's Disease Quality of Life Questionnaire were increased at months 3, 6, and 12. CONCLUSION: Extradural motor cortex stimulation is a safe procedure. After 12 months, the patients demonstrated a moderate improvement of motor symptoms (particularly axial symptoms) and quality of life.