J R Hodges

..Part II of this review (Hodges and Miller, 2001) sets the special issue papers within the context of advances in the neuropsychology of frontal variant FTD and semantic dementia...

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..Other topics discussed include the impact of semantic breakdown on phonological processes and episodic memory. We also review recent structural and functional neuroimaging findings in semantic dementia...

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..Unlike other frontotemporal dementia syndromes, the neuropathological findings in SD are fairly predictable: most patients have ubiquitin-positive, tau-negative neuronal inclusions...

..The results suggest that object use is heavily dependent upon object-specific conceptual knowledge, supplemented to some degree by a combination of visual affordances and mechanical problem solving...

..To establish whether the frontal and temporal variants of FTD are characterised by different behavioural changes...

..The second part attempts to review the current status of our knowledge concerning behavioural, neuropsychological and neuropsychiatric aspects of the disease, emphasizing areas of continuing controversy...

..The frontal and temporal presentations of FTD are clearly separable from each other and from early AD...

..To establish survival in patients with pathologically confirmed frontotemporal dementia (FTD) and to determine whether clinical or pathologic subtype affects prognosis...

..Therefore, the pathological substrate can be predicted in a significant proportion of FTD patients, which has important implications for studies targeting mechanistic treatments...

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..These results support the view that new episodic learning typically draws on information from both perceptual and semantic systems...

..Person knowledge deficits are, therefore, not specific to AD and the employment of face stimuli may influence the performance of SD patients on tasks of episodic memory...

..The focal syndrome may remain pure for many years. Patients with atypical AD tend to be older than those with non-AD pathology...

..Our aim was to test the hypothesis that clinical, but not pathologic, classification (FTD with ubiquitin inclusions [FTD-U] and FTD with tau inclusions [FTD-T]) is associated with predictable patterns of regional atrophy...

..To account for these findings, we propose a revision to current models of long-term memory, in which sensory/perceptual information and semantic memory work in concert to support new learning...

..The results are discussed with respect to current views of long-term memory, particularly new word learning and forgetting, and to current techniques for facilitating word finding in aphasia...

..The results of our investigations suggest a particular role for the striatum in context-dependent action selection, in line with current computational theories of basal ganglia function...

..Nonetheless, we discuss how damage to semantic knowledge could result in an autobiographical memory deficit and suggest that data from semantic dementia may be consistent with both views of hippocampal involvement in long-term memory...

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..Standard verbal episodic memory tests, therefore, failed to discriminate patients with SD from those with probable AD and even visual memory tests may result in misclassification of SDR cases...

..QD patients' performance correlated with the degree of subsequent global cognitive decline. Elements of contextual and cued recall may account for the task's sensitivity and specificity for AD...

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..This result provides support for the view that new learning is primarily dependent upon the hippocampus and related structures...

..Our study investigated whether this variability is due to the admixture of patients with true bvFTD and phenocopy patients. We also sought to compare performance of patients with bvFTD and patients with Alzheimer disease (AD)...

..N., a pathologically confirmed case of MND/dementia. Finally, we attempt to characterise the nature of the linguistic impairment in MND in the light of current debates about the mechanisms underlying noun/verb dissociation...

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..To evaluate activities of daily living (ADLs) in three clinical variants of frontotemporal dementia and the relationship to cognitive dysfunction...

..Age-of-acquisition and word frequency (at a phonological-lexical level) predicts naming success, because frequent, early-acquired words are relatively easy to activate even with reduced semantic "input"...

..The pattern of cognitive impairment is likely to reflect a different distribution of pathology, in particular a higher degree of cortical involvement in PSP and CBD...

..Recent findings indicate that the syndrome of semantic dementia can inform us about the organisation of long-term memory and the relationship between semantic memory and other cognitive systems...

..The current study investigates whether the two groups can be discriminated by their clinical features at first presentation...

..Some features are open to clinical interpretation and their prevalence unknown. This study investigated the sensitivity of current diagnostic criteria in a large group of patients with bvFTD...

..Further studies are required to establish whether MND/dementia and MND/aphasia form separate disease entities or can be viewed as extreme forms of a cognitive deficit characteristic of MND in general...

..The implications of this finding for diagnostic procedures and possible behavioural management are discussed...

..Scores for irritability and cognitive failures were high in the sample. There was no correlation between any psychiatric variable and CAG repeats. Possible explanations for this lack of correlations are discussed...

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..This case demonstrates that the pattern of FTD may include severe anterograde amnesia as a prominent and early consequence of the disease...

..The results lead us to favor a model of the semantic system that is divided by attribute type but not by modality...

..Patients with MCI show deficits of episodic and semantic memory. The extent of impairment suggests dysfunction beyond the medial temporal lobe. The FPT might form the basis of a sensitive early indicator of AD...

..These findings have implications for diagnosis and understanding of the cognitive deficits in AD and semantic dementia...

..Many of the neuropsychological deficits thought to characterise Alzheimer's disease are also found in subcortical vascular dementia...

..In addition, these results point towards the importance of investigating the constituent elements of emotion processing and strategic retrieval processes as potential variables mediating recent episodic ABM retrieval...

..CONCLUSION: The profile of cognitive performance shows selective and progressive dysfunction of attention and executive function in patients with mild to moderate HD, consistent with frontostriatal pathology at this stage of disease...

..Both verbs and nouns are affected by the degradation of semantic memory; the fact that the impairment to noun production is manifested earlier and more catastrophically may be attributed to the relatively lower frequency of these terms...

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..Behavioral variant frontotemporal dementia (bvFTD) patients show prefrontal cortex dysfunction and atrophy...

..In conclusion, atrophy of the human perirhinal cortex, and of directly connected areas, was associated with semantic memory impairment but not episodic memory impairment, as predicted from the primate work...

..A semantic deficit together with the hallmark episodic deficit may be common in MCI, and that the use of graded tasks tapping semantic memory may be useful for the early identification of patients with MCI...

..These findings extend existing theoretical accounts of MTL function, and challenge current concepts of cognitive impairment in dementia...

..Although such cases may mimic more focal lobar degenerative conditions, patients with atypical Alzheimer's disease have pronounced episodic memory impairments, suggesting amnesia as a critical diagnostic feature...

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..This study examined functional changes in progressive non-fluent aphasia (PNFA) and logopenic progressive aphasia (LPA) and Alzheimer's disease (AD) and the association between function, cognition and behaviour...

..This study aimed to improve sensitivity of clinicopathologic relations in cases with neuropathologically confirmed Pick disease and to identify clinical symptoms and signs predictive of disease progression...

..At present there is a paucity of prospective work addressing the specificity of current diagnostic criteria for bvFTD with respect to long-term outcome (i.e., false positives versus true positives)...

..CONCLUSIONS: In comparison with other neurodegenerative conditions such as Alzheimer's disease and Parkinson's disease, neither tau gene mutations nor strong familial associations confer earlier disease susceptibility...

..To estimate the incidence of early-onset dementias in a defined area of Cambridgeshire served by Addenbrooke's Hospital...

..The acknowledgement of deficits in emotion recognition is important for management of both patients and their carers...

..This pattern of deficits closely resembles that seen after tryptophan depletion. Results are discussed with respect to current theories on serotonergic modulation of orbitofrontal/ventromedial prefrontal cortex...

..CONCLUSION: Complex stereotypic behaviours are a core feature of the dementing syndrome in FTD and may reflect early and specific deficits in orbitofrontal circuitry and basal ganglia involvement...

..These results have implications for our understanding of the neural correlates of perceptual and semantic contributions to recognition memory...

..Frontal eye field hypometabolism secondary to loss of input from the occipito-parietal region may be the mechanism for the ocular apraxia seen in Balint's syndrome...

..Full-blown dementia may take many years to develop in patients with MCI but was a universal feature in this study...

..P.'s deficit for person knowledge and predominantly left temporal atrophy in M.A. who was impaired in general conceptual knowledge...

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..The results are discussed in light of neuroimaging findings in studies of social cognition and the locus of pathology in fvFTD...

..Hence, phonemic switching alone drove verbal fluency performance and this selective impairment can be explained by the progressive involvement of frontostriatal circuitry in the natural progression of HD...

..These results, plus other features of the data such as the nature of the errors to irregular verbs, are discussed in relation to currently developing theories of the language system...

..Little is known about its rate of progression but a recently identified subgroup seems to have an excellent prognosis. Other determinants of survival are unclear...

..The results are discussed with respect to current views of the neural organisation of person-specific and general semantic memory...

..The implication of these findings for models of face identification and naming are discussed...

..There is a need for instruments which can measure progression of disease in frontotemporal dementia (FTD), particularly with respect to the assessment of potential therapeutic agents...

..We investigated executive and behavioral profiles of progressive and nonprogressive bv-FTD patients to establish diagnostic markers discriminating the two groups...

..The results are discussed in terms of the 'somatic marker' hypothesis of impaired decision-making following orbitofrontal dysfunction...

..This dissociation suggests that these two aspects of visual attention are subserved by different neural systems. The possible neural correlates of these two attentional functions are discussed...

..The frontal paracingulate correlation suggests that damage to this region may significantly contribute to the genesis of the behavioural syndrome seen in FTD...

..These results provide further compelling evidence in favour of the multiple input model of long-term memory and highlight the role of frontal lobe systems in recollection-based memory...

..These findings are discussed with regard to the neural substrate of episodic memory and psychological models of long-term memory...

..The amnesia of very early AD reflects severe but localized limbic dysfunction...

..More systematic investigation of the clinical and neuropathological overlap between progressive nonfluent aphasia (generally considered to be a form of frontotemporal dementia) and CBD is needed...

..An assessment including measures of episodic memory and visuospatial abilities as well as the semantic battery is recommended for good characterisation of the cognitive profiles associated with SD and AD...

..This study supports the hypothesis that patients with fvFTD, but not those with Alzheimer's disease, are impaired on tests of ToM, and may explain some of the abnormalities in interpersonal behaviour that characterize fvFTD...

..CBS is frequently associated with Alzheimer's disease pathology. Early episodic memory impairment versus early behavioral symptomatology appears to best predict AD or CBD pathology in life...

..While the latter is an aggressive disorder, the former is more benign and unstable even in a clinic setting. Patients with scores >88 on the ACE and/or <14 errors on the PAL can be confidently reassured of a good prognosis...

..We investigated whether an initial neuropsychological assessment could predict rapid progression over 12 months, from amnestic mild cognitive impairment (aMCI) to Alzheimer's disease (AD)...

..By demonstrating a link between pathology, genetics, imaging and abstract cognitive impairments this study advances our understanding of degenerative brain disease with implications for both neuroscience and clinical practice...

..Psychiatric profiles of two at-risk groups [Huntington's disease (HD) gene carriers and non-carriers] were compared by means of a computerized battery and a structured interview...

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..Taken together, the present findings indicate that the K257T mutation in Tau can cause a dementing condition similar to Pick's disease...

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..In summary, whole-brain regional evaluation in SD, in comparison with normal controls and FTD-MND, found anterior temporal atrophy encompassing the perirhinal cortex with relative sparing of adjacent posterior temporal regions...

..The results indicate that posterior cingulate cortex atrophy is present from the earliest clinical stage of sporadic AD and that this region is as vulnerable to neurodegeneration as the hippocampus...

..This study aimed to characterize a large group of progressive aphasic patients from a single center (n = 38), first clinically by case note review, and then pathologically...

..JM's pattern of impairment is discussed in the context of other recent cases of FRA and developments in models of normal memory function...

..These novel observations imply that the human MTL subserves both perceptual and mnemonic functions, with the hippocampus and perirhinal cortex playing distinct roles in spatial and object discrimination, respectively...