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Lisa Cipolotti

Publications and source records attributed to Lisa Cipolotti.

26 records · Page 2Linked to original sources
PubMed2004

The natural history of Alzheimer disease: a longitudinal presymptomatic and symptomatic study of a familial cohort.

BACKGROUND: Knowledge of the evolution of cognitive deficits in Alzheimer disease is important for our understanding of disease progression. Previous reports, however, have either lacked detail or have not covered the presymptomatic stages. OBJECTIVE: To delineate the onset and progression of clinical and neuropsychological abnormalities in familial Alzheimer disease. METHODS: Nineteen subjects with familial Alzheimer disease underwent serial clinical and neuropsychological assessments. Eight of these had undergone presymptomatic assessments. The follow-up period was 1 to 10 years (mean, 5 years). The relative timing of the occurrence of 3 markers of disease onset and progression (onset of symptoms, Mini-Mental State Examination score < or = 24, and impaired scores on a range of neuropsychological tests) were compared using the binomial exact test. RESULTS: Neurological abnormalities were not prominent, although myoclonus appeared early in some. Mini-Mental State Examination score was not sensitive to early disease. Memory and general intelligence deficits appeared at an earlier stage, in some patients when presymptomatic. Perceptual, naming, and especially spelling skills were preserved to a late stage. CONCLUSION: Familial Alzheimer disease may have a long prodromal phase of several years with subtle deficits initially of general intelligence and memory, while spelling, naming, and perception are relatively preserved until a late stage.

Adult↗
PubMed2004

Preserved knowledge of maps of countries: implications for the organization of semantic memory.

We describe two patients with selectively preserved knowledge of the category of countries. Following a series of cerebral infarcts, patient DB presented with severe perceptual impairment, including dense apperceptive agnosia,prosopagnosia, and topographical agnosia. Despite these deficits, he could effortlessly name countries from their outline maps. Patient WH, who suffered from semantic dementia, had severe naming and comprehension difficulties, with extremely sparse residual semantic knowledge. Remarkably, the category of countries was preserved. First, we argue that, for both patients, this category preservation occurs at a semantic level. Second, we discuss our findings in the context of three current models of category-specific effects (perceptual, ontogenetic, and evolutionary models). We argue that the perceptual model (Humphreys and colleagues) cannot easily accommodate our findings. By contrast, the ontogenetic (Warrington and colleagues) and evolutionary models (Caramazza and colleagues) can explain our findings. However, some modifications to both models are required. The ontogenetic model needs to envisage a spatial channel for the development of map knowledge, which is anatomically separate from channels of other categories of knowledge. The evolutionary model needs to envisage the possibility that some categories of knowledge, such as countries, may not be prewired, but learned during ontogenetic development.

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PubMed2004

Monitoring cognitive changes: psychometric properties of six cognitive tests.

OBJECTIVES: Repeated neuropsychological assessments are often used to monitor change in cognitive functioning over time. Thus, knowledge about the reliability and stability of neuropsychological tests and the effects of age and IQ is of paramount importance. In this study we document, for six cognitive tests: test-retest reliabilities, practice effects, reliable change (RC) indices corrected for practice, and the impact of premorbid IQ and age. DESIGN: A sample of 188 normal adults (aged 40-70 years) were administered, on two occasions, one or more of the following tests: the Graded Naming Test (GNT), the Silhouettes Test, two tests of verbal fluency, the Modified Wisconsin Card Sorting Test, and a new test of speed and attention (the Symbol Digit Test). There was a 1-month interval between assessments. At first assessment, all participants were administered the revised National Adult Reading Test (NART). RESULTS: The test-retest reliability of the tests ranged from very good (the GNT and Silhouettes Test) to moderate (verbal fluency tests and Symbol Digit Test) and to poor (Modified Card Sorting Test). Significant, although modest, practice effects were found on all tests. RC indices were generally large except for the Graded Naming Test and the Silhouettes Test. Premorbid IQ scores significantly correlated with performance on all the tests, the exception being semantic fluency. Age only correlated with the Silhouettes Test and the new Symbol Digit Test. Neither NART IQ nor age correlated with practice effects. CONCLUSION: The psychometric properties of the GNT and Silhouettes Test indicated that they are useful tools for monitoring even small cognitive changes. In contrast, the verbal fluency tests and the new Symbol Digit Test are only suitable for monitoring large changes in performance. The Modified Card Sorting Test is an unreliable tool for monitoring 'executive' functions.

Adult↗
PubMed2003

Human cingulate cortex and autonomic control: converging neuroimaging and clinical evidence.

Human anterior cingulate function has been explained primarily within a cognitive framework. We used functional MRI experiments with simultaneous electrocardiography to examine regional brain activity associated with autonomic cardiovascular control during performance of cognitive and motor tasks. Using indices of heart rate variability, and high- and low-frequency power in the cardiac rhythm, we observed activity in the dorsal anterior cingulate cortex (ACC) related to sympathetic modulation of heart rate that was dissociable from cognitive and motor-related activity. The findings predict that during effortful cognitive and motor behaviour the dorsal ACC supports the generation of associated autonomic states of cardiovascular arousal. We subsequently tested this prediction by studying three patients with focal damage involving the ACC while they performed effortful cognitive and motor tests. Each showed abnormalities in autonomic cardiovascular responses with blunted autonomic arousal to mental stress when compared with 147 normal subjects tested in identical fashion. Thus, converging neuroimaging and clinical findings suggest that ACC function mediates context-driven modulation of bodily arousal states.

Adult↗
PubMed2003

Test-retest reliability, practice effects and reliable change indices for the recognition memory test.

OBJECTIVES: The Recognition Memory Test (RMT) is widely used; however, important characteristics such as reliability and stability over time were largely unknown. In this study, we document for the first time test-retest reliabilities, practice effects, and Reliable Change (RC) indices for this test. DESIGN: A sample of 206 normal adults (aged 40-70) were administered twice either the same version or two different versions of the RMT, with a 1-month interval between assessments. The normal sample was split into two groups; a young (aged 40-54) and an old (55-70) group. RESULTS: Test-retest reliabilities were modest when using either the same versions or different versions. Practice effects were abolished when different versions of the RMT were used. In contrast, practice effects were clearly present on the same version of the non-verbal subtest for both control groups. However, practice effects were present on the same versions of the verbal subtest only in the old group. RC indices were rather large when using the same or different versions. CONCLUSION: Although modest, the test-retest reliability of the RMT is no worse than those reliabilities reported for other commonly used recall memory tests. Thus, the inherent clinical advantages of using a recognition paradigm make its use desirable. Usage of different versions of the RMT enables us to avoid practice effects. However, the RC indices indicate that large changes in scores are needed to detect a significant improvement or decline in an individual's performance.

Adult↗
PubMed2002

Are multiplication facts implemented by the left supramarginal and angular gyri?

A patient with presumed cerebral vasculitis showed preserved single digit multiplication facts and impaired single digit subtraction facts. Her ability to comprehend and manipulate numerical quantities was intact. Detailed analysis of her MRI-scan revealed a lesion involving the left parietal lobe including the supramarginal gyrus up to the intraparietal sulcus and extending posteriorly to involve part of the angular gyrus. This finding contradicts a previous report by Lee [Ann. Neurol. 48 (2000) 657] suggesting that these areas are critical for multiplication. In addition, this case contradicts the predicted association between subtraction and quantity manipulation, proposed by Dehaene's triple-code model [Cortex 33 (1997) 219].

Adult↗
PubMed2002

Mechanisms underlying perseveration in aphasia: evidence from a single case study.

Aphasic individuals often inappropriately and unintentionally repeat recent responses, errors termed recurrent perseverations. In a series of picture naming experiments, we investigated the impact of manipulating stimulus factors on the number of perseverations produced by an aphasic patient (E.B.) with markedly impaired naming skills. E.B. produced significantly more perseverations to pictures with low frequency names and following stimulus repetition. In contrast, semantic relatedness and presentation rate failed to influence perseveration. Our results are considered in the context of theories that relate recurrent perseverations to intact priming mechanisms [Brain 121 (1998) 1641; Aphasiology 12 (1998) 319; J. Exp. Psychol. Learn. Mem. Cogn. 19 (1993) 243]. We conclude that these theories can correctly predict some but not all aspects of E.B.'s perseverations. In particular, they failed to predict that: (1) perseverations often appeared to reflect the earlier sequential proximity of stimuli and responses; and (2) perseverations became less likely as more experimental trials intervened, a trend that did not interact with presentation rate. We review evidence relating recurrent perseverations to neuromodulatory deficits and we conclude that a theory of the functional role of neuromodulation in the cerebral cortex proposed by Hasselmo [Neural Netw. 7 (1994) 13] is capable of accounting for all aspects of E.B.'s perseverative behavior.

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