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M Abernethy

Publications and source records attributed to M Abernethy.

At least 19 recordsLinked to original sources
PubMed1996

Semantic category priming in the left cerebral hemisphere.

The representation of semantic codes in the cerebral hemispheres and the interhemispheric communication of these codes, was investigated in two priming experiments where prime and target words were independently projected to the left or right visual fields (LVF or RVF). Nonassociated category exemplars were employed as related pairs in a lexical decision task and separated by a stimulus onset asynchrony of 250 msec in Experiment 1 and 450 msec in Experiment 2. Both experiments obtained priming effects when primes and targets were both projected to the RVF, but not the LVF. Semantic category primes projected to the RVF also facilitated responses to LVF targets, but no LVF-RVF priming was obtained. This suggests that semantic category information is relayed from left to right hemisphere, but not vice versa. The results are consistent with the view that semantic categories are represented in the left hemisphere.

Adult↗
PubMed1994

Picture-name priming in the cerebral hemispheres.

In a lexical decision task, pictures and names of common objects were presented in succession to the left or right visual fields in an investigation of the relationship between visual and verbal representations within and between the hemispheres. On each trial, a picture was projected to the left or right side of the visual field, followed by a string of letters to the same or different side. The letter string could be the name of the object in the picture, an unrelated word, or a nonword. Although a strong priming effect was observed when the name of an object followed its picture, this did not depend on which visual fields had registered the stimuli. Activation of name codes was apparently independent of visual field of presentation of picture and word. This result was consistent with the view that representational systems for pictures and their names are not differentially specialized across the hemispheres. A further finding was that absolute response time to words was shorter when stimuli were divided between the visual fields, even at an SOA of 1000 msec. It is suggested that this result is due to the activation of picture-processing mechanisms within a hemisphere by the first (pictorial) stimulus, which causes a delay in processing the subsequent verbal stimulus in that hemisphere.

Adult↗
PubMed1994

Doppler echocardiography and the early diagnosis of carditis in acute rheumatic fever.

BACKGROUND: The incidence of acute rheumatic fever in New Zealand remains relatively high. Reliable early diagnosis of carditis is difficult and important in management. AIM: To determine if Doppler echocardiography contributed to the early diagnosis of carditis in acute rheumatic fever. METHODS: Forty-seven patients admitted to hospital with suspected acute rheumatic fever and 19 control patients, with a febrile illness due to a documented non-cardiac bacterial infection, were assessed two days and two weeks following admission. Presence or absence of clinical carditis was determined by a cardiologist unaware of the suspected diagnosis, from clinical examination, chest radiograph, electrocardiogram (ECG) and two dimensional echocardiogram. Doppler echocardiography was then performed and interpreted by a second cardiologist unaware of the diagnosis. After completion of the study the Jones criteria were applied, to categorise the patients with suspected acute rheumatic fever into four groups for the final diagnosis: no acute rheumatic fever, possible acute rheumatic fever, definite acute rheumatic fever without carditis, and definite acute rheumatic fever with carditis. RESULTS: In 19 patients with a final diagnosis of acute rheumatic fever and carditis at the baseline assessment carditis was detected by clinical assessment in 15 patients, compared with 19 patients with evidence of significant valve regurgitation by Doppler echocardiography. Following the two week assessment, all 19 patients had both clinical and Doppler evidence of carditis. Five patients with a final clinical diagnosis of possible acute rheumatic fever or definite acute rheumatic fever without carditis, had a Doppler abnormality detected. There was no clinical or Doppler abnormality in the febrile controls. CONCLUSIONS: Doppler echocardiography is more sensitive than clinical assessment in the detection of carditis in acute rheumatic fever, and can contribute to earlier diagnosis.

Acute Disease↗
PubMed1993

Associative priming in the hemispheres as a function of SOA.

The representation of associative codes in the cerebral hemisphere was investigated in two priming experiments where associated prime and target words were independently projected to the left or right visual fields. The first experiment, using a stimulus onset asynchrony of 250 msec, found priming in all visual field conditions, except that in which both prime and target were projected to the right hemisphere. A second experiment was conducted to determine whether this absence of right hemisphere priming was due to an inadequate interval of time between prime and target. In this experiment, a stimulus onset asynchrony of 450 msec revealed significant priming in all visual field conditions. The results suggest that lexical representations are activated more slowly in the right hemisphere than in the left.

Adult↗
PubMed1991

Echocardiographic prediction of left ventricular volume after myocardial infarction.

Left ventricular volume is a strong determinant of survival after acute myocardial infarction. The aim of this study was to determine which clinical and echocardiographic criteria assessed early after myocardial infarction would predict later left ventricular dilation. Forty-eight patients with uncomplicated transmural myocardial infarction had echocardiography 5 to 10 days after myocardial infarction and assessment of clinical variables including peak creatine kinase and sum of electrocardiographic ST segment elevation. Left ventricular dimensions were measured from the echocardiogram in the parasternal view and also in the apical four and two chamber views at the level of the mitral leaflets, papillary muscles and apex. A cardiac wall motion score was obtained by segmental analysis of the apical views. Echocardiographic left ventricular volume was measured after 1 year from the apical views with use of a Simpson's rule method. Initial clinical and echocardiographic variables were correlated with the left ventricular volume at 1 year. There was a significant relation between the initial four and two chamber end-diastolic dimensions and the left ventricular volume at 1 year, particularly for dimensions measured at the apical level (four chamber R2 = 0.66, p = 0.0001, two chamber R2 = 0.61, p = 0.0001). Other clinical variables, parasternal left ventricular dimensions and cardiac wall motion score were not significantly related to left ventricular volume. A powerful three variable model obtained by multiple regression and including the initial two chamber apical dimension, cardiac wall motion score and body surface area accounted for 82% of the variation in left ventricular volume at 1 year.

Cardiac Volume↗
PubMed1990

Semantic and phonemic priming in the cerebral hemispheres.

Representation of semantic and phonemic codes in the cerebral hemispheres was investigated in two priming experiments where prime and target words were independently projected to the left or right visual fields. The first experiment, using phonemic primes, confirmed the view that phonological information is not accessible to the right hemisphere. Priming effects were obtained only when the prime and target were both projected to the right visual field. The second experiment, employing category exemplars as primes, again found the left hemisphere to be the principal locus of the priming effects. The right hemisphere was unable, by itself, to activate words related to the exemplar prime. However, projection of the prime to the right visual field significantly facilitated responses to left visual field targets. The present findings support the view advanced by Drews (Neuropsychologia 25, 419-427, 1987) and Levy and Trevarthen (J. exp. Psychol., Hum. Percep. Perform. 2,299-312, 1976) that the left lexicon is structured in accordance with an hierarchy of logical semantic relationships, while the right lexicon is organized on the basis of simple associations between concepts. It is suggested, furthermore, that the patterns of semantic, but not phonological, activation invoked by a prime may be relayed between the two lexicons.

Adult↗
PubMed1988

Models for costing patient care services, Part 3. Costing operating theatre procedures.

This is the third of a series of papers describing the development of costing models for use in the Clinical Information System (CIS) at the Clayton Campus (formerly the Queen Victoria Medical Centre) of the Monash Medical Centre (MMC) in Melbourne. The first two papers in this series described the costing of diagnostic laboratory services and organ imaging services. This paper describes the development of a model for costing operating theatre procedures.

Accounting↗
PubMed1987

Models for costing patient care services. Part 1: Costing diagnostic laboratory services.

Clinical Information Systems that link resource use to clinical decision making are a necessary tool for effective hospital management. This article describes the cost finding research undertaken to develop a model for costing laboratory tests. The method separately calculates direct labour and direct consumable costs and apportions indirect labour, indirect consumable costs and hospital and department overhead costs to each test in each accounting period. The costing model has been computerised as part of the Queen Victoria Medical Centre's Clinical Information System.

Accounting↗
PubMed1976

Cigarette smoking in pregnancy: Associations with maternal weight gain and fetal growth.

1159 mother-infant "pairs" have been studied to examine the inter-relationship of cigarette smoking in the latter half of pregnancy, maternal weight gain, and fetal growth. Non-smokers gained significantly more weight than heavy smokers (greater than 15 cigarettes per day) while light-to-moderate smokers (1-14 cigarettes a day) were intermediate. Birth-weight, length, and head circumference of the infants showed a similar gradient with infants born to non-smokers being heavier, longer, and with larger head circumferences than those born to heavy smokers. Co-variance analysis showed that a large part of the effect of maternal smoking is mediated through maternal weight gain with only a very small additional direct effect on the fetus. This suggests that increasing weight gain in smoking mothers might prevent some of the harmful effects of smoking on fetal growth. A randomised controlled trial of diet supplementation of smoking mothers would seem justified.

Birth Weight↗
PubMed1976

Trace elements in water and congenital malformations of the central nervous system in South Wales.

The concentrations of 20 trace elements were determined by atomic absorption spectrophotometry on representative samples of tap-water collected from 48 local authority areas in South Wales. The associations between twelve trace elements and central nervous system (CNS) malformation rates for the 48 areas were examined. Significant correlations for four trace elements were observed. Of these, Al was positively correlated while for the remaining three-Ca, Ba, and Cu-negative associations were found. Regression analysis of the data suggested that the relationships between Ba and Cu with CNS malformation rates were improtant than those of Al and Ca.

Aluminum↗
PubMed1976

An international haematological survey.

Haematological surveys of adult population samples were conducted simultaneously in 12 countries, all but one of which are in Europe. Haematological estimations on samples from nine of the countries were made in one central laboratory. Differences between countries in the mean levels of haemoglobin (and haematocrit and red cell count) were found to be relatively small, and the prevalence of levels below the arbitrary WHO levels for anaemia were, on the whole, low. In males, the evidence suggests a fall in haemoglobin level throughout adult life, which increases slightly in advanced age. In females, there is no evidence of any important relationship between age and haemoglobin level.

Adolescent↗
PubMed1970

Clinical significance of dysuria in women.

During a community survey 22% of women were found to have had dysuria in the previous year and half had had dysuria at some time in their lives. Various measurements were made in a random sample of 282 of these women. The means and the variances of the systolic and diastolic blood pressures in women with a past history of dysuria tended to be higher than in women who gave no such history. There were no significant differences in the means of plasma urea, plasma creatinine, and renal concentrating power between women with and without a previous history of dysuria, but a significant impairment of renal concentrating power was found in an additional group of 30 women who dated the onset of their dysuria to childhood.These findings suggest that urinary tract infection in adult women does not usually lead to progressive impairment of kidney function, whereas infection in childhood is more often associated with kidney damage.

Adult↗