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Annalena Venneri

Publications and source records attributed to Annalena Venneri.

17 recordsLinked to original sources
PubMed2004

The evolution of dysgraphia in Alzheimer's disease.

Evidence from recent studies suggests that writing may be an aspect of cognition capable of identifying impairments specific to patients with Alzheimer's Disease (AD). The precise nature and progression of the writing disorder, however, remains unclear. The current study assessed the central and peripheral aspects of writing among a sample of minimal, mild and moderate AD patients and a group of healthy elderly controls on a narrative description task. Comparisons of the two groups indicated that AD patients suffer from a primary impairment at the semantic level. Even those in the minimal stages of the disease could be differentiated from controls on measures of word finding and information conveyed. This semantic impairment was coupled with a secondary milder impairment in phonological processing. The prevalence of phonological errors increased, but no shift in error type (plausible/implausible) was identified as the disease progressed. In addition to the central impairments, patients evinced damage at the peripheral level. In the more severe stages, patients experienced more problems with letter formation and stroke placement and tended to rely upon the more simplistic writing form of print. The writing impairment in AD is multi-componential in nature and follows the pattern of cortical deterioration reported in the brains of AD patients.

Aged↗
PubMed2004

Belief and awareness: reflections on a case of persistent anosognosia.

Persisting anosognosia after acute lesions is relatively rare, and no case studies to date have reported functional scanning investigation of this disorder. This is a case report of an 85-year-old right-handed Scottish woman, EN, who showed persistent anosognosia for hemiplegia following a haemorrhagic stroke. Extensive damage in the right hemisphere caused left upper and lower limb flaccid hemiplegia and severe left-sided neglect. Lack of awareness for her deficits was still present 2 years after the stroke, when neurological, neuropsychological, and SPECT examinations were performed. Testing revealed severe left unilateral neglect and poor performance on verbal fluency tasks. EN had age normal memory performance, and her object recognition and praxic abilities were preserved. She showed no global reasoning or language problems apart from her abnormal beliefs. EN believed that she was able to walk and carry out several activities, in a context of other disorders of belief. SPECT scan showed marked hypoperfusion in the right parietotemporal cortex and this extended to the associative cortex in the right frontal regions. The persistence of anosognosia in this patient cannot be explained by memory impairments or global cognitive decline. A possible account might be that alteration in awareness was maintained by contingent right frontal and/or parietal dysfunction causing a suspension or change in the ability to monitor and check the 'real' and especially to assess the veracity of mental contents.

Aged↗
PubMed2004

Modified Card Sorting Test: normative data.

The Modified Card Sorting Test (MCST), a shortened version of the Wisconsin Card Sorting Test, proposed by Nelson in 1976 is a neuropsychological test that is widely used in clinical settings for the evaluation of executive functions in patients with focal, traumatic and degenerative brain diseases. Despite its frequent use, normative data for the MCST are scant. The aim of this study was to collect normative data for the MCST on a sample including 248 healthy individuals ranging from 20 to 90 years of age and equally distributed for education level and sex (124 males and 124 females). Performance on the MCST was scored by computing the number of categories achieved by a participant, and the number of perseverative errors. Multiple regression analyses revealed a significant effect of age and education on the number of categories and perseverative errors but no effect of sex. Cut-off scores were then determined and equivalent scores computed for both the number of categories and the perseverative errors. The availability of normative data for the MCST will be very valuable in clinical settings for testing patients with focal, traumatic and degenerative brain diseases. The use of reference norms will permit a better characterisation of a patient's impaired and spared abilities.

Adult↗
PubMed2003

A case for case: handling letter case selection in written spelling.

This study reports the unusual writing performance of a 72-year-old woman, Pp, who was unable to maintain her writing within a particular case, and made numerous case mixing errors (e.g. insTEAd). Her oral spelling was flawless, but when tested using a written spelling task (including words and non-words), a picture description task, a sentence writing task and a transcription task (from upper case to lower case, and vice versa), she showed a high proportion of case mixing errors, though spelling per se was correct. The problem, although less severe, was also present when spelling with letter cards. Despite a spared ability to select the correct letters in the stimulus, specify the correct number of letters and place them in the correct order, she had a specific problem in selecting the appropriate case. This impairment is indicative of peripheral dysgraphia. She appeared to have intact orthographic representations, but selection of the appropriate allographic codes for upper and lower case was impaired. Her longitudinal neuropsychological profile and MRI evidence suggest that Pp suffers from mild vascular dementia with more severe impairments in attentional functions. Her writing deficits may be accounted for by a model that incorporates an inhibitory mechanism, which is responsible for maintaining the appropriate case and inhibiting the inappropriate one, subsequent to case selection in writing. Failure of this mechanism would explain the pattern of case mixing shown by Pp.

Aged↗
PubMed2003

Brain activation and the phonological loop: the impact of rehearsal.

Brain activation studies offer valuable techniques for exploring human cognition to complement behavioral measures and several studies report a wide range of neuroanatomical networks activated during verbal immediate memory. Behavioral investigations have shown use of multiple cognitive strategies across and within individuals, although aggregate data appear to reflect a common cognitive function. Variation in cognitive strategies could result in aggregate activation patterns that are relatively widespread and difficult to interpret. Imaging data (fMRI) from six participants instructed to use subvocal rehearsal showed significant left hemisphere activation in the inferior parietal gyrus and inferior and middle frontal gyri, a pattern of activation more clearly focused than in previous brain activation studies of immediate verbal serial ordered recall. Our results should be relatively free of the influence of other mental operations, and emphasise the importance of considering which cognitive strategies might give rise to focused or to diverse patterns of brain activation.

Adult↗
PubMed2003

Intra-individual measures of association in neuropsychology: inferential methods for comparing a single case with a control or normative sample.

Performance on some neuropsychological tests is best expressed as an intra-individual measure of association (such as a parametric or non-parametric correlation coefficient or the slope of a regression line). Examples of the use of intra-individual measures of association (IIMAs) include the quantification of performance on tests designed to assess temporal order memory or the accuracy of time estimation. The present paper presents methods for comparing a patient's performance with a control or normative sample when performance is expressed as an IIMA. The methods test if there is a significant difference between a patient's IIMA and those obtained from controls, yield an estimate of the abnormality of the patient's IIMA, and provide confidence limits on the level of abnormality. The methods can be used with normative or control samples of any size and will therefore be of particular relevance to single-case researchers. A method for comparing the difference between a patient's scores on two measures with the differences observed in controls is also described (one or both measures can be IIMAs). All the methods require only summary statistics (rather than the raw data from the normative or control sample); it is hoped that this feature will encourage the development of norms for tasks that use IIMAs to quantify performance. Worked examples of the statistical methods are provided using data from a clinical case and controls. A computer program (for PCs) that implements the methods is described and made available.

Adult↗
PubMed2003

Arithmetic difficulties in children with visuospatial learning disability (VLD).

Eighteen children with visuospatial learning disability (VLD) were compared to normal control children on a series of numerical and calculation tasks. Oral and written (dictated) calculation was assessed and operations differed not only in terms of the type of number processing requirements but also in terms of their visuospatial demand. The aim was to disentangle errors due to visuospatial processing failure from those deriving from incorrect knowledge of calculation procedures. Results showed that all children had relatively good knowledge of numerical facts and there was no statistical difference between the groups. No group difference was found in the overall performance in oral calculation, but a significant difference was present when the children were required to complete the operations in writing, with the VLD group achieving poorer performance than the controls. Furthermore, VLD children had greater difficulties when operations required borrowing or carrying; this was particularly problematic in subtractions. The results indicate that VLD children do not have a generalised problem with calculation per se or number manipulation in general. Rather their problems concern dealing with some processes that govern calculation especially those loading on visuospatial abilities.

Analysis of Variance↗
PubMed2003

Upper and lower face and ideomotor apraxia in patients with Alzheimer's disease.

INTRODUCTION: Apraxia of face movement in Alzheimer's disease (AD) has been rarely investigated. This study aimed at investigating the frequency of lower (mouth, tongue and throat) and upper (eyes and eyebrows) face apraxia, in AD and its relationship with limb apraxia and severity of dementia. METHODS: Fifty seven patients with AD were tested with a new standardised test of face apraxia including upper and lower face movements, which uses an item-difficulty weighted scoring procedure, the IMA test, a test of ideomotor apraxia and the M.O.D.A., a means to assess dementia severity. RESULTS: Thirteen (23%) and 19 (33%) participants were below cut-off respectively on the upper and lower face apraxia test. Both sections of the Face Apraxia Test correlated significantly with the Ideomotor Apraxia Test. However, double dissociations between different types of apraxia were observed. Both the upper and lower face apraxia tests correlated significantly with the measure of dementia severity. CONCLUSIONS: The finding show that a proportion of AD patients fails face apraxia tests. Their face apraxia is interlinked with ideomotor limb apraxia, although dissociations are possible. Severity of dementia deterioration accounts for a good proportion of the variability of AD patients' performance on face apraxia tests.

Aged↗
PubMed2003

A preliminary study of the cognitive mechanisms supporting time estimation.

Evidence from neuropsychological studies has suggested that verbal and visuospatial abilities might be differentially involved in time perception and that, because there is specialised competence, the two brain hemispheres might play different roles in time-keeping mechanisms. Reported are results of three experiments in which the time estimates of normal adults were tested using a prospective paradigm while they were engaged in concurrent secondary tasks requiring visuospatial or verbal memory and attention. Analysis showed no convincing evidence in support of a differential role of either verbal or visuospatial abilities in time estimation. The greatest disruption in time accuracy was detected when participants performed the time estimation tasks concurrently with secondary working memory tasks. These findings emphasize the importance of the involvement of specific cognitive systems rather than cognitive domains in the processing of temporal information.

Adult↗
PubMed2002

Cerebral blood flow and cognitive responses to rivastigmine treatment in Alzheimer's disease.

Twenty seven patients with mild AD were enrolled in a prospective open label controlled study of rivastigmine. Assessments included a range of neuropsychiatric and behavioural measures and rCBF using HMPAO SPECTat baseline, three and six months. Significant enhancement of frontal, parietal and temporal brain blood flow with related psychometric improvement was observed in twelve of the treated patients. A pattern of reduced rCBF and cognitive performance was observed in four unresponsive and eleven untreated patients. The results suggest that alterations in the clinical and cognitive status of patients receiving a cholinesterase inhibitor are paralleled by changes in rCBF. Longitudinal assessment with repeated imaging offers a method of better understanding the effects of cholinesterase inhibition on the AD brain.

Aged↗
PubMed2002

Memory and dating of past events in schizophrenia.

Memory deficits are frequently observed in schizophrenia but their intrinsic characteristics have not been clarified. We studied remote memory in a group of 20 schizophrenics and 20 healthy age and education matched controls using a newly devised public event questionnaire (PEQ) that employs a free recall, progressive cueing and recognition protocol and requires dating of events. Results indicate that patients with chronic schizophrenia perform significantly more poorly on the PEQ than a group of age and education matched controls both in terms of content and dating of events. The number of events recalled does not improve with progressive cuing or recognition. No distinctive pattern was observed in their temporal gradient. There was no significant difference in content scores for pre- and post-onset events in the schizophrenics. These findings indicate that remote memory deficits in chronic schizophrenics arise from deficient encoding rather than from a retrieval deficit secondary to executive dysfunction.

Adult↗
PubMedDate not supplied

A rapid screening measure for the identification of visuospatial learning disability in schools.

Verbal and nonverbal forms of developmental learning disabilities have been reported. Whereas there are several instruments for evaluating children for the presence of verbal learning disabilities at school, no screening tool is available to identify children who have nonverbal learning disabilities. This study aimed at devising and validating a short screening questionnaire that can be used by teachers in primary schools to identify those children who need to be referred for clinical services because they have a visuospatial learning disability (VSLD). An 18-item Shortened Visuospatial Questionnaire (SVS) was derived from an earlier, longer version. Its validation procedure was twofold and was achieved by (a) verifying that children who had been identified with the SVS questionnaire as having a VSLD actually showed visuospatial deficits on psychometric evaluation and by (b) rating with the SVS a clinically identified population of children with VSLD. The results of the validation procedure showed that the SVS is a quick, reliable, and valid instrument that may be helpful in identifying children with VSLD in primary school.

Adolescent↗
PubMedDate not supplied

Distinct patterns of spontaneous speech deterioration: an early predictor of Alzheimer's disease.

Although distinctive patterns of language impairment have been identified in Alzheimer's Disease (AD) patients, few studies have been conducted to identify the errors that consistently differentiate minimal and mild AD patients from healthy elderly individuals. Twenty-two AD patients (11 minimal and 11 mild) and 22 age- and education-matched healthy controls, were assessed on a simple and complex picture description task. The task assessed several aspects of spontaneous speech, including melodic line, articulation, grammatical form, phrase length, paraphasias, word-finding difficulties, error monitoring, information conveyed, and information content. Although both pictures could differentiate between the AD patients and the healthy controls, results suggested that the complex task was most sensitive. Performance on the latter task indicated that minimal AD patients and healthy controls could be differentiated on several measures of semantic processing. Errors point to a breakdown in lexical semantic processing, which occurs earlier in the disease process than previously reported.

Adult↗