Determining the Impact of Autobiographical Experience on "Meaning": New Insights from Investigating Sports-related Vocabulary and Knowledge in Two Cases with Semantic Dementia

Snowden, Griffiths, and Neary (1994, 1995) have proposed thatautobiographical experience helps to maintain the integrity of semantic memory in patients with semantic dementia. We investigated this hypothesis by testing knowledge related to golf and bowls in two case studies. If Snowden and colleagues' hypothesis is correct, our two patients should have better semantic knowledge for the sport that they regularly experience, compared with knowledge of other sports. In keeping with Snowden et al's hypothesis, we found that autobiographical experience influenced the ability of the patients to match up a surname with a first name: The names of personally and currently relevant golf bowls partners were more likely to be matched correctly than such personally relevant names from the past, or the names of famous sports celebrities. Unlike Snowden et al., however, we found that knowledge of people, in all categories, was severely impoverished and that any semantic information was produced as part of an autobiographical memory. Likewise, detailed study of each patient's understanding of their favourite sportrevealed no significanteffectof autobiographical experience on true semantic knowledge. We propose that the ability of semantic dementia patients to encode, albeit temporarily, recent autobiographical memories via a spared hippocampal complex supports the production of highly autobiographically constrained semantic-like facts and, to a lesser extent, frequently encountered names. There is, however, no direct effect of autobiographical experience on previously established semantic memory, i.e. knowledge of golf, bowls, and people, presumably stored within the temporal neocortex. These results are discussed with respect to current anatomically based computational models of long-term memory

Conservation of ciliary proteins in plants with no cilia

<p>Abstract</p> <p>Background</p> <p>Eukaryotic cilia are complex, highly conserved microtubule-based organelles with a broad phylogenetic distribution. Cilia were present in the last eukaryotic common ancestor and many proteins involved in cilia function have been conserved through eukaryotic diversification. However, cilia have also been lost multiple times in different lineages, with at least two losses occurring within the land plants. Whereas all non-seed plants produce cilia for motility of male gametes, some gymnosperms and all angiosperms lack cilia. During these evolutionary losses, proteins with ancestral ciliary functions may be lost or co-opted into different functions.</p> <p>Results</p> <p>Here we identify a core set of proteins with an inferred ciliary function that are conserved in ciliated eukaryotic species. We interrogate this genomic dataset to identify proteins with a predicted ancestral ciliary role that have been maintained in non-ciliated land plants. In support of our prediction, we demonstrate that several of these proteins have a flagellar localisation in protozoan trypanosomes. The phylogenetic distribution of these genes within the land plants indicates evolutionary scenarios of either sub- or neo-functionalisation and expression data analysis shows that these genes are highly expressed in <it>Arabidopsis thaliana </it>pollen cells.</p> <p>Conclusions</p> <p>A large number of proteins possess a phylogenetic ciliary profile indicative of ciliary function. Remarkably, many genes with an ancestral ciliary role are maintained in non-ciliated land plants. These proteins have been co-opted to perform novel functions, most likely before the loss of cilia, some of which appear related to the formation of the male gametes.</p

A questionable semantics: The interaction between semantic knowledge and autobiographical experience in semantic dementia

In our earlier article, we proposed that recent episodic experiences in patients with semantic dementia support the production of nongeneralisable, autobiographically constrained, “semantic-like” facts (Graham, Lambon Ralph, & Hodges, 1997). We argued that this type of “semantic-like” knowledge was distinguishable from true semantic information because our two patients with semantic dementia showed no facilitatory effect of recent autobiographical experiences on their knowledge of golf and bowls; information which was presumably learnt prior to the onset of their disease. In this paper, we discuss the implications of these results for current views relating to the nature and organisation of long-term memory

Naming in semantic dementia - What matters?

One of the major symptoms of semantic dementia (or progressive fluent aphasia) is profound word-finding difficulties. We present here a cross-sectional study of the factors affecting picture naming in semantic dementia based on data obtained from eight patients, together with a longitudinal analysis of naming in another patient. Various properties and attributes of the objects were entered into a series of regression analyses in order to predict which items the patients could or could not name. The analyses showed that object familiarity, word frequency and age-of-acquisition predicted naming success for the group and, in most cases, for each individual patient, irrespective of lesion site or overall naming success. We propose that the pattern of naming in semantic dementia is best described in terms of reduced semantic activation within a cascading\interactive speech production system. We suggest that object familiarity, and possibly word frequency, reflect the inherent robustness of individual semantic representations to the decay process in terms of both quantity and quality of experience. 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"

Emergency Care Handover (ECHO study) across care boundaries : the need for joint decision making and consideration of psychosocial history

Background: Inadequate handover in emergency care is a threat to patient safety. Handover across care boundaries poses particular problems due to different professional, organisational and cultural backgrounds. While there have been many suggestions for standardisation of handover content, relatively little is known about the verbal behaviours that shape handover conversations. This paper explores both what is communicated (content) and how this is communicated (verbal behaviours) during different types of handover conversations across care boundaries in emergency care. Methods: Three types of interorganisational (ambulance service to emergency department (ED) in ‘resuscitation’ and ‘majors’ areas) and interdepartmental handover conversations (referrals to acute medicine) were audio recorded in three National Health Service EDs. Handover conversations were segmented into utterances. Frequency counts for content and language forms were derived for each type of handover using Discourse Analysis. Verbal behaviours were identified using Conversation Analysis. Results: 203 handover conversations were analysed. Handover conversations involving ambulance services were predominantly descriptive (60%–65% of utterances), unidirectional and focused on patient presentation (75%–80%). Referrals entailed more collaborative talk focused on the decision to admit and immediate care needs. Across all types of handover, only 1.5%–5% of handover conversation content related to the patient's social and psychological needs. Conclusions: Handover may entail both descriptive talk aimed at information transfer and collaborative talk aimed at joint decision-making. Standardisation of handover needs to accommodate collaborative aspects and should incorporate communication of information relevant to the patient's social and psychological needs to establish appropriate care arrangements at the earliest opportunity