Lexical access across languages: a multinomial model of auditory distraction

Recall in many types of verbal memory task is reliably disrupted by the presence of auditory distracters, with verbal distracters frequently proving the most disruptive (Beaman, 2005). A multinomial processing tree model (Schweickert, 1993) is applied to the effects on free recall of background speech from a known or an unknown language. The model reproduces the free recall curve and the impact on memory of verbal distracters for which a lexical entry exists (i.e., verbal items from a known language). The effects of semantic relatedness of distracters within a language is found to depend upon a redintegrative factor thought to reflect the contribution of the speech-production system. The differential impacts of known and unknown languages cannot be accounted for in this way, but the same effects of distraction are observed amongst bilinguals, regardless of distracter-language.

Lexical access, story re-telling and sequencing skills in adults who clutter and those who do not

Cluttering is a rate-based disorder of fluency, the scope of whose diagnostic criteria currently remains unclear. This paper reports preliminary findings from a larger study which aims to determine whether cluttering can be associated with language disturbances as well as motor and rate based ones. Subtests from the Mt Wilga High Level Language Test (MWHLLT) were used to determine whether people who clutter (PWC) have word finding difficulties, and use significantly more maze behaviours compared to controls, during story re-telling and simple sequencing tasks. Independent t tests showed that PWC were significantly slower than control participants in lexical access and sentence completion tasks, but returned mixed findings when PWCs were required to name items within a semantic category. PWC produced significantly more maze behaviour than controls in a task where participants were required to explain how to undertake commonly performed actions, but no difference in use of maze behaviour was found between the two groups when retelling a story from memory. The implications of these findings are discussed

Assessing multilingual lexical incorporation hypotheses through a primed picture-naming task

The incorporation of new representations into the mental lexicon has raised numerous questions about the organisational principles that govern the process. A number of studies have argued that similarity between the new L3 items and existing representations in the L1 and L2 is the main incorporating force (Hall & Ecke, 2003; Herwig, 2001). Experimental evidence obtained through a primed picture-naming task with L1 Polish-L2 English learners of L3 Russian supports Hall and Ecke’s Parasitic Model of L3 vocabulary acquisition, displaying a significant main effect for both priming and proficiency. These results complement current models of vocabulary acquisition and lexical access in multilingual speakers.

Word frequency and bigram frequency effects on linguistic processing and speech motor performance in individuals with aphasia and normal speakers

Models of normal word production are well specified about the effects of frequency of linguistic stimuli on lexical access, but are less clear regarding the same effects on later stages of word production, particularly word articulation. In aphasia, this lack of specificity of down-stream frequency effects is even more noticeable because there is relatively limited amount of data on the time course of frequency effects for this population. This study begins to fill this gap by comparing the effects of variation of word frequency (lexical, whole word) and bigram frequency (sub-lexical, within word) on word production abilities in ten normal speakers and eight mild–moderate individuals with aphasia. In an immediate repetition paradigm, participants repeated single monosyllabic words in which word frequency (high or low) was crossed with bigram frequency (high or low). Indices for mapping the time course for these effects included reaction time (RT) for linguistic processing and motor preparation, and word duration (WD) for speech motor performance (word articulation time). The results indicated that individuals with aphasia had significantly longer RT and WD compared to normal speakers. RT showed a significant main effect only for word frequency (i.e., high-frequency words had shorter RT). WD showed significant main effects of word and bigram frequency; however, contrary to our expectations, high-frequency items had longer WD. Further investigation of WD revealed that independent of the influence of word and bigram frequency, vowel type (tense or lax) had the expected effect on WD. Moreover, individuals with aphasia differed from control speakers in their ability to implement tense vowel duration, even though they could produce an appropriate distinction between tense and lax vowels. The results highlight the importance of using temporal measures to identify subtle deficits in linguistic and speech motor processing in aphasia, the crucial role of phonetic characteristics of stimuli set in studying speech production and the need for the language production models to account more explicitly for word articulation.

Morphological decomposition in Broca's aphasia

Background: Few studies have investigated how individuals diagnosed with post-stroke Broca’s aphasia decompose words into their constituent morphemes in real-time processing. Previous research has focused on morphologically complex words in non-time-constrained settings or in syntactic frames, but not in the lexicon. Aims: We examined real-time processing of morphologically complex words in a group of five Greek-speaking individuals with Broca’s aphasia to determine: (1) whether their morphological decomposition mechanisms are sensitive to lexical (orthography and frequency) vs. morphological (stem-suffix combinatory features) factors during visual word recognition, (2) whether these mechanisms are different in inflected vs. derived forms during lexical access, and (3) whether there is a preferred unit of lexical access (syllables vs. morphemes) for inflected vs. derived forms. Methods & Procedures: The study included two real-time experiments. The first was a semantic judgment task necessitating participants’ categorical judgments for high- and low-frequency inflected real words and pseudohomophones of the real words created by either an orthographic error at the stem or a homophonous (but incorrect) inflectional suffix. The second experiment was a letter-priming task at the syllabic or morphemic boundary of morphologically transparent inflected and derived words whose stems and suffixes were matched for length, lemma and surface frequency. Outcomes & Results: The majority of the individuals with Broca’s aphasia were sensitive to lexical frequency and stem orthography, while ignoring the morphological combinatory information encoded in the inflectional suffix that control participants were sensitive to. The letter-priming task, on the other hand, showed that individuals with aphasia—in contrast to controls—showed preferences with regard to the unit of lexical access, i.e., they were overall faster on syllabically than morphemically parsed words and their morphological decomposition mechanisms for inflected and derived forms were modulated by the unit of lexical access. Conclusions: Our results show that in morphological processing, Greek-speaking persons with aphasia rely mainly on stem access and thus are only sensitive to orthographic violations of the stem morphemes, but not to illegal morphological combinations of stems and suffixes. This possibly indicates an intact orthographic lexicon but deficient morphological decomposition mechanisms, possibly stemming from an underspecification of inflectional suffixes in the participants’ grammar. Syllabic information, however, appears to facilitate lexical access and elicits repair mechanisms that compensate for deviant morphological parsing procedures.

Disabled access and heritage attractions

In a UK context, the importance of heritage tourism, the potential of the disabled market, and government policies concerning tourism, social inclusion, and the historic environment provide the setting within which access improvements at heritage attractions for disabled visitors are studied. At issue is how disabled access and conservation can be reconciled. The stakeholders range from the central actors, the disabled tourists and the heritage tourism service providers, through to the gatekeeper and lobby players in the conservation, disability, and tourism contexts. The critical power structures are identified. Changes to the historic environment are managed through the conservation planning system in which disability interests are not formally represented. Recent disability discrimination legislation has not altered this balance of power, and is a source of uncertainty over the access standards that should apply to heritage attractions. An evaluation of progress in implementing access improvements at heritage attractions reveals the limited extent of improvements undertaken to date. Consideration is given not only to physical access but also to alternative methods (intellectual access) of providing the heritage tourism service. In conclusion, the situation is examined from three perspectives. From the disabled tourists' perspective, choice of heritage attractions to visit remains restricted compared to that of nondisabled tourists. The lack of consultation with disabled stakeholders in the access improvements decision-making process is discussed, including the acceptability of alternative methods of service delivery to disabled tourists. The uncertainties facing heritage tourism service providers arising from the disability discrimination legislation are considered but, to ensure a more balanced recognition of disability interests, both conservation planning and disability discrimination legislation need to be amended, adjusting the roles of the legislative gatekeepers.

Access to historic environments for tourists with disabilities: a compromise?

Historic environments, the basis for heritage tourism, are difficult to access for people with disabilities. Many countries have introduced legislation to promote equal rights for people with disabilities. Historic environments, however, enjoy protection under national planning systems which limit the physical access improvements that can be made. The significance of historic environments for tourism in the UK is outlined. Barriers restricting tourists with disabilities accessing historic sites are reviewed from the heritage tourism service provider's viewpoint. Interests of the major stakeholders are considered in terms of the apparent conflict between conservation and access issues as heritage tourism service providers seek to comply with disability discrimination legislation. From a study of access improvements made by major heritage tourism service providers, good practice is identified. However, physical access improvements to enable tourists with disabilities to visit historic environments are a compromise because of the strength of conservation interests. Questions remain as to whether this compromise is acceptable to the tourist with disabilities and whether intellectual access is an acceptable substitute for physical presence.

Promoting inclusion: facilitating access to the Silchester 'town life' project

It is becoming increasingly difficult to resource field archaeology outside the developer-funded context. Consequently it is difficult to engage the wider public in understanding the nature of archaeology and in the writing of its history from the study of material and environmental evidence. This paper describes a project funded by the UK's Heritage Lottery Fund designed to increase access by several means to a well-established and long-running archaeological excavation at the Iron Age and Roman Town at Silchester, Hampshire (UK).

Enantioselective Intramolecular Michael Addition of Nitronates onto Conjugated Esters: Access to Cyclic γ-Amino Acids with up to Three Stereocenters

A highly stereoselective synthesis of conformationally constrained cyclic γ-amino acids has been devised. The key step involves an intramolecular cyclization of a nitronate onto a conjugated ester, promoted by a bifunctional thiourea catalyst. This methodology has been successfully applied to generate a variety of γ-amino acids, including some containing three contiguous stereocenters, with very high diastereoselectivity and excellent enantioselectivity. It is postulated that an interaction that is key to the success of the process is the simultaneous coordination of the thiourea functionality to both the conjugated ester and the nitronate. Finally, the synthetic utility of these compounds is demonstrated in the synthesis of two dipeptides derived from the C- and N-termini.

What's in a name? Lexical knowledge drives infants' visual preferences in the absence of referential input

Seventeen-month-old infants were presented with pairs of images, in silence or with the non-directive auditory stimulus 'look!'. The images had been chosen so that one image depicted an item whose name was known to the infant, and the other image depicted an image whose name was not known to the infant. Infants looked longer at images for which they had names than at images for which they did not have names, despite the absence of any referential input. The experiment controlled for the familiarity of the objects depicted: in each trial, image pairs presented to infants had previously been judged by caregivers to be of roughly equal familiarity. From a theoretical perspective, the results indicate that objects with names are of intrinsic interest to the infant. The possible causal direction for this linkage is discussed and it is concluded that the results are consistent with Whorfian linguistic determinism, although other construals are possible. From a methodological perspective, the results have implications for the use of preferential looking as an index of early word comprehension.

Access, equity and the role of rights in health care

Modern health care rhetoric promotes choice and individual patient rights as dominant values. Yet we also accept that in any regime constrained by finite resources, difficult choices between patients are inevitable. How can we balance rights to liberty, on the one hand, with equity in the allocation of scarce resources on the other? For example, the duty of health authorities to allocate resources is a duty owed to the community as a whole, rather than to specific individuals. Macro-duties of this nature are founded on the notion of equity and fairness amongst individuals rather than personal liberty. They presume that if hard choices have to be made, they will be resolved according to fair and consistent principles which treat equal cases equally, and unequal cases unequally. In this paper, we argue for greater clarity and candour in the health care rights debate. With this in mind, we discuss (1) private and public rights, (2) negative and positive rights, (3) procedural and substantive rights, (4) sustainable health care rights and (5) the New Zealand booking system for prioritising access to elective services. This system aims to consider: individual need and ability to benefit alongside the resources made available to elective health services in an attempt to give the principles of equity practical effect. We describe a continuum on which the merits of those, sometimes competing, values-liberty and equity-can be evaluated and assessed.