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1.
Neuropsychologia ; 159: 107926, 2021 08 20.
Article in English | MEDLINE | ID: mdl-34216595

ABSTRACT

Data gathered in the field of the experimental social psychology have shown that it is more difficult to recognize a person through his/her voice than through his/her face and that false alarms (FA) are produced more in voice than in face recognition. Furthermore, some neuropsychological investigations have suggested that in patients with damage to the right anterior temporal lobe (ATL) the number of FA could be higher for voice than for face recognition. In the present study we assessed FA during recognition of famous people from faces and voices in patients with unilateral ATL tumours and in normal participants tested after anodal transcranial direct current stimulation (tCDS), over the left or right ATL. The number of FA was significantly higher in patients with right than in those with left temporal tumours on both face and voice familiarity. Furthermore, lesion side did not differentially affect patient's sensitivity or response criterion when recognizing famous faces, but influenced both these measures on a voice recognition task. In fact, in this condition patients with right temporal tumours showed a lower sensitivity index and a lower response criterion than those with left-sided lesions. In normal subjects, the greater right sided involvement in voice than in face processing was confirmed by the observation that right ATL anodal stimulation significantly increased voice but only marginally influenced face sensitivity. This asymmetry between face and voice processing in the right hemisphere could be due to the greater complexity of voice processing and to the difficulty of forming stable and well-structured representations, allowing to evaluate if a presented voice matches or not with an already known voice.


Subject(s)
Facial Recognition , Transcranial Direct Current Stimulation , Voice , Female , Humans , Male , Recognition, Psychology , Temporal Lobe
2.
Neuropsychologia ; 116(Pt B): 194-204, 2018 07 31.
Article in English | MEDLINE | ID: mdl-28733246

ABSTRACT

Twenty-nine patients who underwent surgery for a temporal glioma, either in the left (16 patients) or right (13 patients) hemisphere, were administered standardized tests of unknown voice discrimination (UVD) and of famous voice recognition (VO-REC), which included tasks of familiarity evaluation, semantic identification and naming of famous voices. The UVD consisted of twenty stimuli, in which two audio files were consecutively presented; the subject was requested to judge whether the voices belonged to the same or different persons. In the VO-REC, patients were requested to recognize the voices of 40 very well known people; these voices were intermingled with the voices of 20 unknown people for a familiarity check, followed by identification and naming of persons recognized as familiar. We aimed at verifying the effect of laterality and intra-temporal site of lesion on familiarity assessment, false alarms, identification and naming of familiar people. As for the effect of lesion side, our results showed that patients with right temporal gliomas were significantly more impaired in voices discrimination and produced more false alarms than patients with a left glioma, who, in turn, were significantly more impaired in name retrieval than patients with a right temporal glioma. The high number of false alarms in patients with a right temporal glioma suggests that familiarity judgment was impaired. Regarding the neuroanatomical correlates of these different patterns of impairment, MRI data suggested that: (a) UVD disorders are due to lesions involving the whole right anterior temporal lobe and extending to lateral portions of the temporal and frontal lobes; (b) familiarity judgments (testified by an increased number of false alarms) are impaired in lesions restricted to the right anterior temporal lobe; (c) name retrieval deficits are found only in patients with left temporal lesions. UVD disorders were interpreted, at least in part, as due to an impairment of executive functions, resulting from a disconnection of the right temporal lobe from the frontal lobe control. A partly unexpected finding was that some patients with a right temporal tumour had a normal performance in famous voice recognition and identification, in spite of having severe voice discrimination disturbances. These unexpected results, in agreement with previous observation made in the visual (face) modality, are inconsistent with strictly hierarchical models of voice processing.


Subject(s)
Brain Neoplasms/complications , Functional Laterality/physiology , Glioma/complications , Memory Disorders/etiology , Recognition, Psychology/physiology , Temporal Lobe/pathology , Adult , Aged , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/pathology , Discrimination, Psychological , Famous Persons , Female , Glioma/diagnostic imaging , Glioma/pathology , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Names , Neuropsychological Tests , Retrospective Studies , Temporal Lobe/diagnostic imaging , Voice , Young Adult
3.
Eur J Neurol ; 23(3): 630-40, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26756166

ABSTRACT

BACKGROUND AND PURPOSE: Depression is common amongst subjects with multiple sclerosis (MS), and several investigations have explored different determinants of this condition, including physical disability, psychological and psychosocial factors. The brain derived neurotrophic factor (BDNF) Val66Met polymorphism has been associated with depression. The aim of this study was to analyze the influence of disease-related factors, BDNF Val66Met polymorphism and perception of disease on the severity of depression in MS. METHOD: In total, 136 MS patients (88 women) were recruited and genotyped for BDNF rs6265 polymorphism at nucleotide 196 (G/A) using 'high resolution melting'. Depressive symptoms were assessed by the Multiple Sclerosis Depression Rating Scale. Perception of health status was assessed using the SF-36 questionnaire. RESULTS: A multivariable linear regression model showed that the best predictors of depression were the SF-36 General health (ß = -0.209; P = 0.013), Mental health (ß = -0.410; P < 0.001) and Social activity (ß = -0.195; P = 0.035) scores; physical disability (assessed by the Extended Disability Status Scale score) was directly correlated to depression severity on univariate analysis, but it was not a relevant predictor of depression on multivariate analysis; other variables directly related to the disease (treatment, annual relapsing rate) and the BDNF Val66Met polymorphism were not significantly associated with depression. CONCLUSION: Perception of the health status is the principal predictor of depressive symptoms in our sample. This result supports the hypothesis that the subjective interpretation of the disease's consequences is one of the main factors in determining depression in MS.


Subject(s)
Brain-Derived Neurotrophic Factor/genetics , Depression/psychology , Multiple Sclerosis/psychology , Adult , Depression/etiology , Depression/genetics , Female , Humans , Male , Middle Aged , Multiple Sclerosis/complications , Multiple Sclerosis/genetics , Polymorphism, Genetic
4.
Neurobiol Learn Mem ; 125: 15-23, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26211873

ABSTRACT

The aims of the present experiment was to investigate: (a) if transient disruption of neural activity in the right (RTP) or left temporal pole (LTP) can interfere with the development of a familiarity feeling to the presentation of faces/written names of famous/unknown people; and (b) if this interference specifically affects the familiarity for faces after inhibition of the RTP and for names after inhibition of the LTP. Twenty healthy volunteers took part in the study. Repetitive transcranial magnetic stimulation (rTMS) was administered online; it disrupted the neural activity of the right or left TP in concomitance with the presentation of each face and name whose familiarity had to be assessed. Furthermore, in a control group, each participant was submitted to a single experimental session in which rTMS was delivered to the vertex in association with the presentation of faces and written names. Since previous rTMS studies have shown that the temporary inactivation of the right and left TP influences the response latencies, but not the number of correct responses, in this study we took into account both the number of correct responses obtained in different experimental conditions and the corresponding response latencies. A three-way factorial ANOVA carried out on the Response Scores showed only a general effect of the Type of Stimuli, due to better performances on names than on faces. This greater familiarity of names is consistent with previous data reported in the literature. In the three-way factorial ANOVA carried out on the Latency Scores, post-hoc analyses showed an increased latency of responses to faces after right stimulation in Latency Total, Latency on Correct responses and Latency on Unfamiliar faces. None of these results were obtained in the control group. These data suggest that rTMS at the level of the RTP preferentially affects the development of familiarity feelings to the presentation of faces of famous people.


Subject(s)
Face , Functional Laterality/physiology , Names , Pattern Recognition, Visual/physiology , Recognition, Psychology/physiology , Temporal Lobe/physiology , Adult , Female , Humans , Male , Neuropsychological Tests , Reaction Time/physiology , Transcranial Magnetic Stimulation , Young Adult
5.
Neurol Sci ; 34(2): 173-80, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22350217

ABSTRACT

Several studies, showing that attention disorders during encoding reduce later memory performance, have stressed the critical role of attention for the formation of durable memory traces. Accordingly, some studies suggest that attentive disturbances, together with declarative memory defects, can constitute the earliest cognitive disorders in Alzheimer's disease. Therefore, the analysis of these disorders can contribute to identify different forms of dementia and to detect demented patients characterized by a faster cognitive decline. In this study, we report the normative data (gathered in a large Italian population) of a short test that assess the ability to detect stimuli characterized by a conjunction of features: the 'Multiple Features Targets Cancellation' task (MFTC). Our sample of 465 subjects was composed by urban and rural people. Multiple linear regression analyses revealed significant relation of false alarms with age and educational level, and of time of execution with age, educational level and gender. Regression analyses on accuracy scores did not show any significant correlation with demographics variables. Based on non-parametric techniques, cutoff scores were obtained on the corrected scores of the patients, and equivalent scores were derived for each measure. The MFTC task represents a useful tool that explores attentional disorders (and in particular conjunction search disturbances) and that could be helpful both in discriminating different forms of dementia and to detect mild cognitive impairment patients at risk of conversion to dementia.


Subject(s)
Attention/physiology , Cognition Disorders/diagnosis , Dementia/diagnosis , Visual Perception/physiology , Adult , Age Factors , Aged , Aged, 80 and over , Cognition Disorders/psychology , Dementia/psychology , Female , Humans , Italy , Male , Middle Aged , Neuropsychological Tests , Reference Values
6.
Eur J Neurol ; 19(9): 1159-79, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22891773

ABSTRACT

BACKGROUND AND OBJECTIVES: The last version of the EFNS dementia guidelines is from 2007. In 2010, the revised guidelines for Alzheimer's disease (AD) were published. The current guidelines involve the revision of the dementia syndromes outside of AD, notably vascular cognitive impairment, frontotemporal lobar degeneration, dementia with Lewy bodies, corticobasal syndrome, progressive supranuclear palsy, Parkinson's disease dementia, Huntington's disease, prion diseases, normal-pressure hydrocephalus, limbic encephalitis and other toxic and metabolic disorders. The aim is to present a peer-reviewed evidence-based statement for the guidance of practice for clinical neurologists, geriatricians, psychiatrists and other specialist physicians responsible for the care of patients with dementing disorders. It represents a statement of minimum desirable standards for practice guidance. METHODS: The task force working group reviewed evidence from original research articles, meta-analyses and systematic reviews, published by June 2011. The evidence was classified (I, II, III, IV) and consensus recommendations graded (A, B, or C) according to the EFNS guidance. Where there was a lack of evidence, but clear consensus, good practice points were provided. RESULTS AND CONCLUSIONS: New recommendations and good practice points are made for clinical diagnosis, blood tests, neuropsychology, neuroimaging, electroencephalography, cerebrospinal fluid (CSF) analysis, genetic testing, disclosure of diagnosis, treatment of behavioural and psychological symptoms in dementia, legal issues, counselling and support for caregivers. All recommendations were revised as compared with the previous EFNS guidelines. The specialist neurologist together with primary care physicians play an important role in the assessment, interpretation and treatment of symptoms, disability and needs of dementia patients.


Subject(s)
Dementia , Alzheimer Disease/diagnosis , Alzheimer Disease/therapy , Dementia/diagnosis , Dementia/therapy , Dementia, Vascular/diagnosis , Dementia, Vascular/therapy , Frontotemporal Lobar Degeneration/diagnosis , Frontotemporal Lobar Degeneration/therapy , Humans , Huntington Disease/diagnosis , Huntington Disease/therapy , Hydrocephalus, Normal Pressure/diagnosis , Hydrocephalus, Normal Pressure/therapy , Lewy Body Disease/diagnosis , Lewy Body Disease/therapy , Limbic Encephalitis/diagnosis , Limbic Encephalitis/therapy , Parkinson Disease/diagnosis , Parkinson Disease/therapy , Primary Progressive Nonfluent Aphasia/diagnosis , Primary Progressive Nonfluent Aphasia/therapy , Prion Diseases/diagnosis , Prion Diseases/therapy , Supranuclear Palsy, Progressive/diagnosis , Supranuclear Palsy, Progressive/therapy
7.
Eur J Neurol ; 17(10): 1236-48, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20831773

ABSTRACT

BACKGROUND AND OBJECTIVES: In 2008 a task force was set up to develop a revision of the European Federation of the Neurological Societies (EFNS) guideline for the diagnosis and management of Alzheimer's disease (AD) and other disorders associated with dementia, published in early 2007. The aim of this revised international guideline was to present a peer-reviewed evidence-based statement for the guidance of practice for clinical neurologists, geriatricians, psychiatrists, and other specialist physicians responsible for the care of patients with AD. Mild cognitive impairment and non-Alzheimer dementias are not included in this guideline. METHODS: The task force working group reviewed evidence from original research articles, meta-analysis, and systematic reviews, published before May 2009. The evidence was classified and consensus recommendations graded (A, B, or C) according to the EFNS guidance. Where there was a lack of evidence, but clear consensus, good practice points were provided. RESULTS: The recommendations for clinical diagnosis, blood tests, neuropsychology, neuroimaging, electroencephalography, cerebrospinal fluid (CSF) analysis, genetic testing, disclosure of diagnosis, treatment of AD, behavioural and psychological symptoms in dementia, legal issues, counselling and support for caregivers were all revised as compared with the previous EFNS guideline. CONCLUSION: A number of new recommendations and good practice points are made, namely in CSF, neuropsychology, neuroimaging and reviewing non-evidence based therapies. The assessment, interpretation, and treatment of symptoms, disability, needs, and caregiver stress during the course of AD require the contribution of many different professionals. These professionals should adhere to these guideline to improve the diagnosis and management of AD.


Subject(s)
Advisory Committees/standards , Alzheimer Disease/diagnosis , Alzheimer Disease/therapy , Nursing, Team/standards , Alzheimer Disease/psychology , Caregivers/standards , Czech Republic , Diagnosis, Differential , Diagnostic Imaging/methods , Diagnostic Imaging/standards , Diagnostic Tests, Routine/methods , Diagnostic Tests, Routine/standards , Early Diagnosis , Humans , Neuropharmacology/methods , Neuropharmacology/standards , Neuropsychological Tests/standards , Nootropic Agents/therapeutic use , Physical Therapy Modalities/standards
8.
J Neurosci Res ; 88(5): 1106-12, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19885866

ABSTRACT

The aim of this study was to investigate the role of Brain Derived Neurotrophic Factor (BDNF) and inflammatory factors in the development of cognitive dysfunctions in Multiple Sclerosis (MS). We correlated peripheral blood mononuclear cell (PBMC) production of BDNF, Tumor Necrosis Factor-alpha (TNF-alpha), Interleukin (IL)-6 and IL-10 with performances on specific neuropsychological tasks in a selected series of MS patients. We studied a sample of 30 patients with relapsing-remitting (RR)MS, segregated by gender and matched for age, education, disease duration, type of immunomodulating therapy, degree of disability and overall cognitive status. We found that low BDNF levels were correlated with increased time of execution on a divided attention and visual scanning task whereas high levels of IL-6 were correlated with low Mini Mental State Examination scores. We did not observe any significant correlations between IL-10, TNF-alpha levels and cognitive performances in our patients. In conclusion our study shows a correlation between low BDNF and high IL-6 production by PBMCs and poorer performances in cognitive tasks in RRMS patients suggesting a possible role of these factors in cognitive impairment in MS.


Subject(s)
Cognition Disorders/metabolism , Cytokines/metabolism , Leukocytes, Mononuclear/metabolism , Multiple Sclerosis, Relapsing-Remitting/metabolism , Nerve Growth Factors/metabolism , Adult , Biomarkers/analysis , Biomarkers/metabolism , Brain/immunology , Brain/metabolism , Brain/pathology , Brain-Derived Neurotrophic Factor/metabolism , Cognition Disorders/immunology , Cognition Disorders/physiopathology , Cohort Studies , Encephalitis/immunology , Encephalitis/metabolism , Encephalitis/physiopathology , Female , Humans , Interleukin-10/metabolism , Interleukin-6/metabolism , Magnetic Resonance Imaging , Male , Middle Aged , Multiple Sclerosis, Relapsing-Remitting/complications , Multiple Sclerosis, Relapsing-Remitting/immunology , Neuropsychological Tests , Statistics as Topic , Tumor Necrosis Factor-alpha/metabolism
9.
Curr Alzheimer Res ; 7(3): 271-9, 2010 May.
Article in English | MEDLINE | ID: mdl-19860723

ABSTRACT

The MCI construct aims to investigate the grey area existing between normal aging and dementia, in order to identify it in the preclinical stage patients at risk of developing dementia. The construct of the MCI has been proposed by taking the neuropathological staging of the Alzheimer's disease (AD) as reference and providing an explicit set of identifying criteria, but it has raised two main problems: (a) the variability of estimates concerning the actual rate of conversion from MCI to dementia, and (b) the number of subjects who return to normality. These problems stem in part from the operational difficulties met by the MCI identifying criteria concerned with: the memory tests used, the cut-off adopted to identify patients with an 'objective' memory disorder, the assessment of subjective memory disorders, and the integrity of daily living activities. After a short discussion of these operational difficulties, I will pass to shortly survey the laboratory data providing additional predictive value for the conversion of MCI to dementia (ApoE4, CSF biomarkers, Neuroimaging data, and Vascular risk factors) and some recent attempts to identify pre-MCI patients, with a purely subjective cognitive impairment. I will conclude my review by asking if we have a single MCI or a family of MCI constructs, each of whom could play a preferential role in specific clinical contexts.


Subject(s)
Alzheimer Disease/diagnosis , Cognition Disorders/diagnosis , Memory Disorders/diagnosis , Aged , Alzheimer Disease/physiopathology , Biomarkers/analysis , Biomarkers/metabolism , Brain/metabolism , Brain/pathology , Brain/physiopathology , Cognition Disorders/physiopathology , Diagnostic Imaging/methods , Diagnostic Imaging/standards , Disease Progression , Early Diagnosis , Humans , Memory Disorders/physiopathology , Predictive Value of Tests , Prognosis
10.
Clin Neurophysiol ; 119(11): 2494-500, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18829384

ABSTRACT

OBJECTIVE: Central cholinergic circuits of human brain can be tested non-invasively by coupling peripheral nerve stimulation with transcranial magnetic stimulation of motor cortex. This test, named short latency afferent inhibition (SAI) has been shown in healthy subjects to be sensitive to the blockage of muscarinic acetylcholine receptors and it is impaired in Alzheimer disease (AD) patients, a cholinergic form of dementia, while it is normal in non-cholinergic forms of dementia such as fronto-temporal dementia. The objective of present study was to evaluate central cholinergic circuits in patients with Vascular Dementia (VaD). METHODS: We evaluated SAI in a group of patients with VaD and compared the data with those from a group of AD patients and a control group of age-matched healthy individuals. RESULTS: Mean SAI was normal in VaD patients while it was significantly reduced in AD patients. The analysis of individual data showed abnormal SAI in 75% of AD and in only 25% of VaD. CONCLUSIONS: SAI is normal in most of VaD patients in contrast with AD patients. This test might be used for the functional evaluation of central cholinergic circuits in VaD patients. SIGNIFICANCE: SAI testing may represent a useful additional tool for the evaluation of patients with VaD however, further studies are required in order to evaluate whether this method can be used for the differential diagnosis between pure VaD and different forms of dementia.


Subject(s)
Acetylcholine/physiology , Brain/metabolism , Dementia, Vascular/pathology , Dementia, Vascular/physiopathology , Aged , Aged, 80 and over , Analysis of Variance , Brain/pathology , Case-Control Studies , Evaluation Studies as Topic , Evoked Potentials, Motor/drug effects , Evoked Potentials, Motor/physiology , Evoked Potentials, Motor/radiation effects , Female , Follow-Up Studies , Humans , Male , Nerve Net/pathology , Neural Inhibition/drug effects , Neural Inhibition/physiology , Neural Inhibition/radiation effects , Neuropsychological Tests , Reaction Time/drug effects , Reaction Time/physiology , Reaction Time/radiation effects , Transcranial Magnetic Stimulation/methods
11.
Dement Geriatr Cogn Disord ; 24(5): 317-26, 2007.
Article in English | MEDLINE | ID: mdl-17851236

ABSTRACT

BACKGROUND/AIMS: Frontal lobe dementia (FLD) and primary nonfluent progressive aphasia (PnPA) are two forms of frontotemporal lobe degeneration. The relationship between these conditions remains unclear. Our study aimed to better define the behavioral and cognitive clusters characterizing PnPA patients. METHODS: We cognitively and behaviorally evaluated three groups of newly diagnosed patients affected by Alzheimer's disease (AD, n=20), FLD (n=22) and PnPA (n=10), in order to assess the cognitive-behavioral pattern of PnPA, compared to both FLD and AD. RESULTS: We found, as expected, worse performances in episodic memory in AD, of both the verbal fluency and naming tasks in PnPA, while FLD mainly showed behavioral disorders associated with an unremarkable deficit in the executive tasks. PnPA was not characterized by any significant behavioral disorders. Factor analysis-extracted three main factors ('mnesic', 'behavioral' and 'linguistic') clearly correlated to each group. A discriminant analysis based on the extracted factors correctly classified 84.6% of all patients. CONCLUSION: The evidence of a characteristics cognitive profile, without any significant behavioral changes, highlights that PnPA is different from other forms of frontotemporal lobe degeneration regarding both the cognitive and behavioral patterns; thus, it should be considered independently in further studies.


Subject(s)
Alzheimer Disease/diagnosis , Aphasia, Primary Progressive/diagnosis , Cognition Disorders/diagnosis , Dementia/diagnosis , Memory Disorders/diagnosis , Mental Disorders/diagnosis , Aged , Alzheimer Disease/complications , Alzheimer Disease/pathology , Analysis of Variance , Aphasia, Primary Progressive/complications , Aphasia, Primary Progressive/pathology , Atrophy , Cognition Disorders/etiology , Cognition Disorders/pathology , Dementia/complications , Dementia/pathology , Diagnosis, Differential , Factor Analysis, Statistical , Frontal Lobe/pathology , Humans , Memory Disorders/classification , Mental Disorders/etiology , Mental Disorders/pathology , Middle Aged , Neuropsychological Tests , Problem Solving , Semantics , Single-Blind Method , Temporal Lobe/pathology , Verbal Behavior
12.
J Neurol Neurosurg Psychiatry ; 78(3): 248-52, 2007 Mar.
Article in English | MEDLINE | ID: mdl-16690696

ABSTRACT

AIM: To assess the long-term cognitive and behavioural outcome after bilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) in patients affected by Parkinson's disease, with a 5-year follow-up after surgery. METHODS: 11 patients with Parkinson's disease treated by bilateral DBS of STN underwent cognitive and behavioural assessments before implantation, and 1 and 5 years after surgery. Postoperative cognitive assessments were carried out with stimulators turned on. RESULTS: A year after surgery, there was a marginally significant decline on a letter verbal fluency task (p = 0.045) and a significant improvement on Mini-Mental State Examination (p = 0.009). 5 years after surgery, a significant decline was observed on a letter verbal fluency task (p = 0.007) and an abstract reasoning task (p = 0.009), namely Raven's Progressive Matrices 1947. No significant postoperative change was observed on other cognitive variables. No patient developed dementia 5 years after surgery. A few days after the implantation, two patients developed transient manic symptoms with hypersexuality and one patient developed persistent apathy. CONCLUSION: The decline of verbal fluency observed 5 years after implantation for DBS in STN did not have a clinically meaningful effect on daily living activities in our patients with Parkinson's disease. As no patient developed global cognitive deterioration in our sample, these findings suggest that DBS of STN is associated with a low cognitive and behavioural morbidity over a 5-year follow-up, when selection criteria for neurosurgery are strict.


Subject(s)
Cognition Disorders , Deep Brain Stimulation , Parkinson Disease/therapy , Subthalamic Nucleus/physiology , Aged , Bipolar Disorder/etiology , Deep Brain Stimulation/adverse effects , Female , Follow-Up Studies , Humans , Male , Mental Status Schedule , Middle Aged , Mood Disorders/etiology , Patient Selection
13.
Neurology ; 66(7): 1111-3, 2006 Apr 11.
Article in English | MEDLINE | ID: mdl-16606932

ABSTRACT

The test of short latency afferent inhibition (SAI) of the motor cortex is helpful in demonstrating dysfunction of central cholinergic circuits in Alzheimer disease (AD). The authors evaluated SAI in 20 patients with frontotemporal dementia (FTD) and compared data with those from 20 patients with AD and 20 controls. SAI was normal in FTD, whereas it was reduced in AD. SAI may represent an additional tool to discriminate FTD from AD.


Subject(s)
Afferent Pathways/physiopathology , Alzheimer Disease/physiopathology , Frontal Lobe/physiopathology , Neural Pathways/physiopathology , Temporal Lobe/physiopathology , Aged , Cholinesterase Inhibitors/therapeutic use , Electrophysiology/methods , Female , Humans , Male , Memory, Short-Term/physiology , Middle Aged , Reaction Time/physiology , Reference Values
14.
J Neurol Neurosurg Psychiatry ; 76(8): 1064-9, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16024879

ABSTRACT

BACKGROUND: In vivo evaluation of cholinergic circuits of the human brain has recently been introduced using a transcranial magnetic stimulation (TMS) protocol based on coupling peripheral nerve stimulation with motor cortex TMS (short latency afferent inhibition, SAI). SAI is reduced in Alzheimer's disease (AD) and drugs enhancing cholinergic transmission increase SAI. METHODS: We evaluated whether SAI testing, together with SAI test-retest, after a single dose of the acetylcholinesterase (AChE) inhibitor rivastigmine, might be useful in predicting the response after 1 year treatment with rivastigmine in 16 AD patients. RESULTS: Fourteen AD patients had pathologically reduced SAI. SAI was increased after administration of a single oral dose of rivastigmine in AD patients with abnormal baseline SAI, but individual responses to rivastigmine varied widely, with SAI change ranging from an increase in inhibition of approximately 50% of test size to no change. Baseline SAI and the increase in SAI after a single dose of rivastigmine were correlated with response to long term treatment. A normal SAI in baseline conditions, or an abnormal SAI in baseline conditions that was not greatly increased by a single oral dose of rivastigmine, were invariably associated with poor response to long term treatment, while an abnormal SAI in baseline conditions in conjunction with a large increase in SAI after a single dose of rivastigmine was associated with good response to long term treatment in most of the patients. CONCLUSIONS: Evaluation of SAI may be useful for identifying AD patients likely to respond to treatment with AChE inhibitors.


Subject(s)
Alzheimer Disease/complications , Alzheimer Disease/drug therapy , Cholinesterase Inhibitors/pharmacology , Cholinesterase Inhibitors/therapeutic use , Cognition/drug effects , Phenylcarbamates/pharmacology , Phenylcarbamates/therapeutic use , Aged , Cholinesterase Inhibitors/administration & dosage , Drug Administration Schedule , Electromagnetic Phenomena/instrumentation , Follow-Up Studies , Humans , Motor Cortex/drug effects , Motor Cortex/pathology , Neural Inhibition/drug effects , Neurons, Afferent/drug effects , Neuropsychological Tests , Phenylcarbamates/administration & dosage , Prospective Studies , Rivastigmine , Severity of Illness Index , Time
15.
Neurol Sci ; 25(4): 192-7, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15549504

ABSTRACT

We investigated if, in patients with vascular lesions, the variable that best discriminated demented from non-demented patients was the severity of the vascular pathology or the degree of hippocampal atrophy. A total of 39 patients multiple subcortical infarcts, who could be considered as possible vascular dementia with small vessel pathology, with underwent a neuropsychological study and brain magnetic resonance imaging (MRI) DSM IV criteria supported by neuropsychological data were used to distinguish demented from non-demented patients. The MRI study took into account the degree of hippocampal atrophy (hippocampal height and interuncal distance) and the severity of vascular pathology (number of brain infarcts). The distribution of lesions and a factor analysis showed that hippocampal atrophy is a better predictor of dementia than the number of brain infarcts. Multiple subcortical infarcts alone are probably not able to cause clinical dementia but the presence of vascular lesions increases the expression of concomitant Alzheimer's disease.


Subject(s)
Atrophy/pathology , Brain Ischemia/pathology , Cerebral Infarction/pathology , Dementia, Vascular/pathology , Dementia, Vascular/psychology , Hippocampus/pathology , Aged , Alzheimer Disease/etiology , Alzheimer Disease/pathology , Alzheimer Disease/psychology , Atrophy/physiopathology , Atrophy/psychology , Brain Ischemia/physiopathology , Brain Ischemia/psychology , Cerebral Arteries/pathology , Cerebral Arteries/physiopathology , Cerebral Infarction/physiopathology , Cerebral Infarction/psychology , Dementia, Vascular/etiology , Diagnosis, Differential , Disease Progression , Female , Hippocampus/physiopathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neuropsychological Tests , Predictive Value of Tests
16.
J Neurol Neurosurg Psychiatry ; 75(4): 555-9, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15026495

ABSTRACT

OBJECTIVES: Recent transcranial magnetic stimulation (TMS) studies demonstrate that motor cortex excitability is increased in Alzheimer's disease (AD) and that intracortical inhibitory phenomena are impaired. The aim of the present study was to determine whether hyperexcitability is due to the impairment of intracortical inhibitory circuits or to an independent abnormality of excitatory circuits. METHODS: We assessed the excitability of the motor cortex with TMS in 28 patients with AD using several TMS paradigms and compared the data of cortical excitability (evaluated by measuring resting motor threshold) with the amount of motor cortex disinhibition as evaluated using the test for motor cortex cholinergic inhibition (short latency afferent inhibition) and GABAergic inhibition (short latency intracortical inhibition). The data in AD patients were also compared with that from 12 age matched healthy individuals. RESULTS: The mean resting motor threshold was significantly lower in AD patients than in controls. The amount of short latency afferent inhibition was significantly smaller in AD patients than in normal controls. There was also a tendency for AD patients to have less pronounced short latency intracortical inhibition than controls, but this difference was not significant. There was no correlation between resting motor threshold and measures of either short latency afferent or intracortical inhibition (r = -0.19 and 0.18 respectively, NS). In 14 AD patients the electrophysiological study was repeated after a single oral dose of the cholinesterase inhibitor rivastigmine. Resting motor threshold was not significantly modified by the administration of rivastigmine. In contrast, short latency afferent inhibition from the median nerve was significantly increased by the administration of rivastigmine. CONCLUSIONS: The change in threshold did not seem to correlate with dysfunction of inhibitory intracortical cholinergic and GABAergic circuits, nor with the central cholinergic activity. We propose that the hyperexcitability of the motor cortex is caused by an abnormality of intracortical excitatory circuits.


Subject(s)
Alzheimer Disease/physiopathology , Cerebral Cortex/physiopathology , Motor Cortex/physiopathology , Nerve Net/physiopathology , Neural Inhibition/physiology , Phenylcarbamates , Afferent Pathways/physiopathology , Aged , Alzheimer Disease/diagnosis , Carbamates , Cholinergic Fibers/physiology , Cholinesterase Inhibitors , Evoked Potentials, Motor/physiology , Female , Humans , Male , Middle Aged , Muscle, Skeletal/innervation , N-Methylaspartate/physiology , Reaction Time/physiology , Rivastigmine , Sensory Thresholds/physiology , Signal Processing, Computer-Assisted , Transcranial Magnetic Stimulation , gamma-Aminobutyric Acid/physiology
17.
J Neurol Neurosurg Psychiatry ; 75(1): 49-55, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14707307

ABSTRACT

BACKGROUND: Previous research on patients with left tactile extinction has shown that crossing of hands, so that each hand is on the opposite side of the body midline relative to the other, improves detection of stimuli given to the left hand. OBJECTIVES: To study the influence of the spatial position of limbs on left tactile extinction, and its relations with left visual neglect. METHODS: Normal participants and patients with right cerebral hemisphere damage and left tactile extinction were asked to detect single or double light touch stimuli applied to their cheeks, hands, or knees with their arm and legs either in anatomical or in crossed position, increasing the attentional load of the task. RESULTS: In patients with left extinction, limb crossing caused a deterioration in performance for stimuli applied to right body parts, with only a tendency to an improvement in detection for left body parts (only two of 24 patients showed substantial (>20%) improvement in left extinction after limb crossing). After crossing, left limb detections of double stimuli decreased with increasing degrees of visual neglect. CONCLUSIONS: In conditions of high attentional load, limb crossing may impair tactile detection in most patients with left extinction, and particularly in those showing signs of left visual neglect. These results underline the importance of general attentional capacity in determining tactile extinction. Attentional and somatotopic mechanisms of extinction may assume different weights in different patients.


Subject(s)
Agnosia/physiopathology , Brain/pathology , Perceptual Disorders/physiopathology , Touch , Aged , Aged, 80 and over , Attention , Female , Functional Laterality , Humans , Male , Middle Aged , Task Performance and Analysis
18.
J Neurol ; 248(9): 743-9, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11596777

ABSTRACT

After having stressed the distinction between general adaptive systems and specific functional systems, the author argues that emotions constitute a general adaptive system distinct from, but interacting with, the cognitive system, considered as the other (more evolved) adaptive system. The main characteristics of the emotional system are its componential nature and its hierarchical organization. These basic features of the emotional system, as well as the brain structures subserving the different components of emotions must, therefore, be taken into account in the neuropsychological study of emotional disorders. The main components of emotions considered in this educational review are: the evaluation of emotional situations; the emotional response with its expressive-motor and autonomic components and the inhibition of socially unacceptable spontaneous emotional responses. The main levels identified in the hierarchical structure of emotions are: a level of automatic, spontaneous functioning and a level of conceptual processing of emotional information and of controlled selection of the most appropriate response. The brain structures identified as critically involved in these different components and levels of emotions are: the amygdala, considered as the structure where the external stimuli are appraised in terms of their emotional significance; the insular cortex and the hypothalamus, crucially involved in the generation of the autonomic components of emotions; the ventral striatum, which subserves the execution of stereotyped emotional action patterns and the ventro-medial frontal cortex, playing a critical role in functions of control and inhibition of socially unacceptable emotional responses. The different emotional involvement of the right and left hemispheres in different aspects and levels of emotional processing is also shortly discussed and the quality of emotional disturbances resulting from injury to these brain structures is briefly considered.


Subject(s)
Affective Symptoms/psychology , Affective Symptoms/diagnosis , Affective Symptoms/physiopathology , Brain/physiology , Brain/physiopathology , Emotions/physiology , Humans , Inhibition, Psychological
19.
Neuropsychologia ; 39(10): 1013-21, 2001.
Article in English | MEDLINE | ID: mdl-11440754

ABSTRACT

Signs of unilateral neglect for events occurring in one hemispace most often result from right hemisphere lesions. Right unilateral neglect after left hemisphere damage is much rarer, and has received less attention. The present study explores the relationships between right unilateral neglect and asymmetries in producing laterally directed arm movements in the horizontal plane in left brain-damaged (LBD) patients. Participants produced right- or left-directed arm movements with their left arm in response to centrally located visual stimuli. Results showed that LBD patients with signs of right unilateral neglect were consistently slowed when producing arm movements toward the right (neglected) side, as compared to left-directed movements. Taking into account patients with and without signs of neglect, this directional asymmetry positively correlated with a reaction-time measure of perceptual spatial bias. These findings stand in contrast with previous results obtained with the same experimental paradigm in right brain-damaged patients, in whom a consistent slowing of leftward-directed movements was rare and apparently unrelated to the presence and severity of left neglect. These conflicting results are discussed with respect to the hypothesis that different mechanisms may underlie left and right unilateral neglect.


Subject(s)
Cerebral Hemorrhage/physiopathology , Cerebral Infarction/physiopathology , Dominance, Cerebral/physiology , Orientation/physiology , Perceptual Disorders/physiopathology , Psychomotor Performance/physiology , Adult , Aged , Aged, 80 and over , Brain Mapping , Cerebral Cortex/physiopathology , Cerebral Hemorrhage/diagnosis , Cerebral Infarction/diagnosis , Female , Hemianopsia/diagnosis , Hemianopsia/physiopathology , Humans , Male , Middle Aged , Neuropsychological Tests , Perceptual Disorders/diagnosis
20.
J Neurol Neurosurg Psychiatry ; 71(2): 258-61, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11459907

ABSTRACT

The aim was to evaluate the effects of poststroke depression and antidepressant therapy on the improvement of motor scores and disability, to verify if the negative effects of poststroke depression on functional recovery could be counterbalanced by taking antidepressant drugs. RESULTS OBTAINED BEFORE, DURING, AND AFTER REHABILITATION: On the Barthel index, Canadian neurological scale, and Rivermead mobility index-by 49 depressed patients with stroke, who had been treated (n=25) or not treated (n=24) according to the different therapeutic approaches of their physicians, were compared with results similarly obtained by 15 non-depressed patients with stroke. Analysis was by multivariate analysis of variance for repeated measures There was a non-significant difference between the groups in their motor and functional scores, and a significant improvement on time. A significant interaction between group and time was seen. This interaction was particularly significant on the Rivermead mobility index, and was due to the fact that the recovery of non-treated depressed patients with stroke was less than the non-depressed and the depressed but treated patients with stroke. Furthermore, recovery from depression was significantly greater in treated than in non-treated depressed patients with stroke. In conclusion, poststroke depression has negative effects on functional recovery, and a pharmacological treatment of depression can counterbalance this effect.


Subject(s)
Antidepressive Agents/therapeutic use , Depressive Disorder/drug therapy , Depressive Disorder/psychology , Stroke/physiopathology , Stroke/psychology , Aged , Analysis of Variance , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Time Factors
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